Diabetes mellitus, particularly type 2, frequently coexists with hypothyroidism, and this intersection is clinically significant since both disorders affect energy balance, weight, lipid metabolism, and cardiovascular risk. Numerous observational studies indicate that thyroid dysfunction, especially subclinical hypothyroidism, is prevalent among patients with type 2 diabetes, implying that a significant subset of diabetic individuals may possess an undiagnosed thyroid disorder that can alter their metabolic profile and symptomatology.[1,2]

From a clinical perspective, undiagnosed hypothyroidism in an individual with diabetes can resemble or exacerbate metabolic complications (fatigue, weight gain, dyslipidaemia, constipation) and may complicate diabetes management by affecting insulin sensitivity, lipid profiles, and potentially blood pressure and cardiovascular risk. Evidence indicates a correlation between thyroid dysfunction and suboptimal glycaemic control (elevated HbA1c) in some cohorts, suggesting that thyroid state may be a possible "concealed factor" in cases of unexplained poor control despite adherence to medication.[3,4]

There exists a pragmatic rationale within healthcare systems: screening practices are inconsistent—certain guidance documents and reviews underscore the lack of uniform “one-size-fits-all” recommendations for routine thyroid testing in all patients with type2 diabetes, while concurrently asserting that a systematic approach may be advantageous for specific patients (e.g., women, the elderly, those with long- standing diabetes, poor control, or dyslipidaemia). The disparity between actual prevalence and inconsistent screening necessitates the use of local clinical data to determine the appropriateness of routine vs tailored screening in a specific context.[5]

Ultimately, Indian and other regional research reveal varying prevalence estimates, affected by age, sex distribution, iodine status, length of diabetes, obesity, and study methodology. This variability underscores the necessity for a targeted clinical study within our hospital/region to (1) assess the prevalence of clinical and subclinical hypothyroidism among diabetic patients, (2) identify correlates including age, sex, duration of diabetes, BMI, HbA1c, and lipid profile, and (3) ascertain whether thyroid dysfunction correlates with diabetic complications in our population—enabling screening and management to be customised to local conditions rather than relying on generalised averages.

AIMS & OBJECTIVES

1. To do the clinical study of hypothyroidism in patients of diabetes mellitus, during the study period in Guntur Medical College.
2. To study the patients having both endocrine disorders and their thyroid function status, in relation to the age and sex, the type of diabetes, age at detection of either condition, the clinical features, relation to the lipid profile, body mass index and other comorbid conditions.
3. To do the clinical study of hypothyroidism in patients of diabetes mellitus, during the study period in Guntur Medical College.
4. To study the patients having both endocrine disorders and their thyroid function status, in relation to the age and sex, the type of diabetes, age at detection of either condition, the clinical features, relation to the lipid profile, body mass index and other comorbid conditions.

Study Design • This study was conducted as an observational, cross-sectional study. Study Period • The study was carried out over a period of 18 months. Study Setting • The study was conducted in the Department of General Medicine, Government General Hospital, Guntur, a tertiary care teaching hospital affiliated with Guntur Medical College, Andhra Pradesh. Study Population • The research population comprised patients with diabetes mellitus, whether previously or newly diagnosed, who attended the outpatient and inpatient services of Government General Hospital, Guntur, during the study period. Sample Size • A total of 150 patients with diabetes mellitus were included in the study. Sampling Method • Patients were selected using simple random sampling from diabetic patients visiting the Government General Hospital, Guntur, during the study period. Inclusion Criteria • Patients with diabetes mellitus, either previously diagnosed or newly diagnosed • Age more than 19 years • Patients willing to participate in the study Exclusion Criteria • Patients aged ≤ 19 years • Patients with hypothyroidism secondary to thyroid surgery or radiotherapy Data Collection • Upon securing informed consent, a comprehensive clinical history was gathered, and an extensive clinical examination was conducted for all participants recruited. Demographic information, clinical characteristics, duration and type of diabetes, age at diagnosis of diabetes and thyroid disease, body mass index, lipid profile, and concomitant comorbidities were documented utilising a pre-structured case record proforma. Clinical Examination Every patient received a comprehensive clinical evaluation, encompassing: • Comprehensive physical assessment • Comprehensive evaluation of the cardiovascular, pulmonary, gastrointestinal, and central nervous systems Laboratory Investigations Routine Investigations • Haemoglobin percentage (Hb%) • Total leukocyte count (TLC), differential count (DC), erythrocyte sedimentation rate (ESR) • Urine analysis for albumin, sugar, and microscopy • Serum urea and creatinine • Electrocardiogram (ECG) • Chest X-ray • Lipid profile Diabetes-Related Investigations • Fasting venous plasma glucose • Two-hour postprandial venous plasma glucose Thyroid-Related Investigations • Serum Thyroid Stimulating Hormone (TSH) • Serum Triiodothyronine (T3) • Serum Thyroxine (T4) Statistical Analysis The gathered data were assembled, organised, and analysed employing suitable statistical techniques. The data were analysed to derive pertinent conclusions aligned with the diagnosis and research objectives

Table 1: Distribution of Subjects According to the Type of Diabetes

Among the 150 subjects included in the present study, the majority were diagnosed with Type 2 diabetes mellitus, comprising 112 cases, while 38 subjects were diagnosed with Type 1 diabetes mellitus. In both categories, male subjects outnumbered female subjects, with males accounting for 72 of the Type 2 diabetes cases and 23 of the Type 1 diabetes cases. Overall, males constituted a higher proportion of the study population compared to females, reflecting a male predominance among diabetic patients in the present study.

Table 2: Distribution of Subjects According to Age Group and Sex (n = 150)

Chi-square test: 0.058; p value = 0.912 (Not Significant)

The age and sex distribution of the study subjects revealed that the highest proportion of diabetic patients belonged to the 40–59 years age group, accounting for 44.0% of the total study population, followed by the 20–39 years age group (28.0%). Male subjects predominated across all age groups. Females were most commonly represented in the 40–59 years age group. Statistical analysis showed no significant association between age group and sex distribution among the study subjects (p > 0.05), indicating that the observed differences were not statistically significant.

Table 3: Known and Newly Detected Cases of Hypothyroidism in Diabetics (n = 150)

Fisher’s Exact test: F = 1.684; p value = 0.194 (Not Significant)

Among the 150 diabetic subjects studied, hypothyroidism was found to coexist in 24 patients, yielding an overall prevalence of 16.0%. Of these, 8 patients were previously known cases of hypothyroidism, while 15 patients were newly detected at the time of first evaluation, and 1 patient developed hypothyroidism during follow-up. The majority of hypothyroid cases occurred in patients who were diagnosed with diabetes mellitus prior to the detection of thyroid dysfunction. Statistical analysis revealed no significant association between the temporal occurrence of diabetes and hypothyroidism (p > 0.05).

Table 4: Newly Detected Cases of Clinical and Subclinical Hypothyroidism Among Diabetics Not Known to Have Hypothyroidism Prior to Inclusion

Out of 150 diabetic subjects, 8 were known hypothyroid at baseline. The remaining

142 subjects were screened for newly detected hypothyroidism.

Among the 142 diabetic patients who were not known to have hypothyroidism prior to inclusion in the study, newly detected hypothyroidism was identified in 17 subjects, giving a detection rate of 12.0%. Subclinical hypothyroidism constituted the majority of newly detected cases, accounting for 14 patients (9.9%), while 3 patients (2.1%) were diagnosed with clinical hypothyroidism. The cases of clinical hypothyroidism were detected during follow-up, highlighting the value of periodic thyroid function screening in diabetic patients.

Table 5: First Detected Condition in Patients Having Both Hypothyroidism (Clinical and Subclinical) and Diabetes Mellitus

Chi-square test = 9.84; p value = 0.007 (Statistically Significant)

Among the 24 subjects diagnosed with both diabetes mellitus and hypothyroidism, diabetes mellitus was the first detected condition in the majority of cases, accounting for 83.3% of patients. Hypothyroidism was detected prior to diabetes mellitus in 12.5% of cases, while both conditions were identified simultaneously in 4.2% of patients. The association between the first detected condition and the coexistence of diabetes mellitus and hypothyroidism was found to be statistically significant (p < 0.05), indicating that diabetes mellitus was more commonly diagnosed before the onset or detection of hypothyroidism in the present study.

Table 6: First Detected Condition and Gap Between the Two Conditions in Patients Having Both Clinical Hypothyroidism and Diabetes Mellitus

Clinical hypothyroidism was observed in 10 diabetic patients, accounting for a prevalence of 6.7% among the study population. Among these patients, diabetes mellitus was the first detected condition in 6 cases (60.0%), followed by clinical hypothyroidism in 3 cases (30.0%). In one patient (10.0%), both conditions were detected simultaneously. The mean interval between the detection of diabetes mellitus and subsequent development of clinical hypothyroidism was approximately

9.8 years, with a range of 1 to 21 years. When clinical hypothyroidism was detected first, the mean interval before the diagnosis of diabetes mellitus was 7.5 years. These findings suggest that diabetes mellitus commonly precedes the development of clinical hypothyroidism in patients with coexisting disease.

Table 7: Use of Oral Antidiabetic Drugs in Type 2 Diabetes Mellitus According to Thyroid Status (n = 112)

Contingency Coefficient (CC) = 0.082; p value = 0.671 (Not Significant)

Among the 112 patients with Type 2 diabetes mellitus, the majority were receiving oral antidiabetic drugs, with an overall usage rate of 94.6%. Oral antidiabetic drug use was observed in 94.6% of euthyroid patients, 91.7% of patients with subclinical hypothyroidism, and in all patients with clinical hypothyroidism. Statistical analysis showed no significant association between thyroid status and the use of oral antidiabetic drugs among Type 2 diabetic patients (p > 0.05).

Table 8: Duration of Use of Oral Antidiabetic Drugs in Different Thyroid Status Groups

ANOVA (F test): F = 1.61; p value = 0.205 (Not Significant)

The mean duration of oral antidiabetic drug use among Type 2 diabetic patients was highest in those with subclinical hypothyroidism, followed by euthyroid patients, and lowest among patients with clinical hypothyroidism. However, the observed differences in the duration of oral antidiabetic drug use across the different thyroid status groups were not statistically significant (p > 0.05), indicating no significant association between thyroid status and duration of oral antidiabetic therapy in the present study.

Table 9: Distribution of Diabetics with Coexisting Hypothyroidism According to Age Group

Contingency Coefficient (CC):Males = 0.342; p = 0.389 (Not Significant); Females

= 0.458; p = 0.162 (Not Significant)

Among the 24 diabetic patients with coexisting hypothyroidism, the majority belonged to the 40–59 years age group, followed by the 20–39 years and ≥60 years age groups. Type 2 diabetes mellitus accounted for most cases across all age groups. Subclinical hypothyroidism was more common than clinical hypothyroidism. Male patients predominated among those with coexisting thyroid dysfunction. Statistical analysis showed no significant association between age group and thyroid status when analysed separately for males and females (p > 0.05).

Table 10: Distribution of Hypothyroid Patients According to Type of Diabetes Mellitus, Sex, and Clinical / Subclinical Hypothyroidism

Contingency Coefficient (CC):

• Males = 0.418; p = 0.002 (Significant)
• Females = 0.602; p< 0.001 (Significant)

Among the 150 diabetic patients studied, both clinical and subclinical hypothyroidism were more commonly observed in females compared to males. Subclinical hypothyroidism was present in 12.7% of female diabetics as compared to 7.4% of male diabetics, while clinical hypothyroidism was seen in 10.9% of females and 4.2% of males. This female predominance was observed in both Type 1 and Type 2 diabetes mellitus. Statistical analysis showed a significant association between sex and thyroid dysfunction among diabetic patients (p < 0.05).

Table 11: Age at Onset of Diabetes Mellitus and Clinical Hypothyroidism and Gap Between the Two Conditions in Patients Having Both Conditions (n = 8)

Among the eight patients with coexisting diabetes mellitus and clinical hypothyroidism, the age at onset of diabetes mellitus ranged from early adulthood to late middle age. In most patients, diabetes mellitus preceded the onset of clinical hypothyroidism, with the interval between the two conditions varying from less than one year to approximately two decades. In one patient, clinical hypothyroidism was detected prior to diabetes mellitus (negative gap), while in one patient both conditions were detected simultaneously. This indicates variability in the temporal relationship between the onset of diabetes mellitus and clinical hypothyroidism in the study population

Table 12: Clinical Symptoms and Signs of Hypothyroidism Among Clinically Hypothyroid Patients (n = 8)

All clinically hypothyroid patients in the study presented with generalised weakness and lethargy. Dryness of skin and cold intolerance were among the most common associated symptoms. Weight gain and decreased sweating were also frequently observed. Gastrointestinal symptoms such as constipation and neurological complaints like paraesthesia were present in nearly half of the patients. Menstrual abnormalities and cardiovascular symptoms were less common. This symptom profile reflects the classical clinical presentation of hypothyroidism in diabetic patients.

Table 13:Clinical Signs of Hypothyroidism Among Clinically Hypothyroid Patients (n = 8)

Delayed relaxation of the ankle jerk was the most frequently observed clinical sign, present in the majority of clinically hypothyroid patients. Cutaneous manifestations such as coarse skin and periorbital puffiness were also commonly noted. Features suggestive of reduced metabolic activity, including slow speech, cold skin, and bradycardia, were observed in a substantial proportion of patients. Other signs such as facial puffiness, goitre, and neuromuscular slowing were less frequent. These findings represent the typical clinical signs of hypothyroidism observed among diabetic patients in the present study.

Table 14: Presence of Goitre in Different Thyroid Status Groups (n = 150)

Contingency Coefficient (CC) = 0.412; p value < 0.001 (Statistically Significant)

Goitre was observed in 8 out of 150 study subjects, giving an overall prevalence of 5.3%. The occurrence of goitre was markedly higher among patients with hypothyroidism, being present in 30.0% of clinically hypothyroid patients and 21.4% of those with subclinical hypothyroidism, compared to only 1.6% among normothyroid subjects. No goitre was observed in the patient with subclinical hyperthyroidism. The association between thyroid status and presence of goitre was found to be statistically significant (p < 0.001). All patients with goitre had diffusely enlarged thyroid glands

Table     15:         Frequency           of           Diabetic Complications    in              Relation              to Thyroid Complications (%)

Analysis of diabetic complications in relation to thyroid status revealed no statistically significant correlation between thyroid dysfunction and the occurrence of complications in both Type 1 and Type 2 diabetes mellitus. Although certain complications appeared numerically higher in specific thyroid subgroups, these differences did not attain statistical significance, indicating that thyroid status did not significantly influence the pattern of diabetic complications in the present study

Table 16: Body Mass Index (BMI), Mean Triglyceride and Cholesterol Levels in Various Groups of Diabetic Patients

Body mass index, mean triglyceride levels, and mean total cholesterol levels were higher among diabetic patients with coexisting hypothyroidism, particularly in those with clinical hypothyroidism, when compared to diabetic patients with normal thyroid status. However, these differences did not reach statistical significance (p > 0.05), indicating that thyroid dysfunction did not have a significant influence on BMI or lipid parameters in the present study.

Thyroid dysfunction, especially hypothyroidism and subclinical hypothyroidism (SCH), is consistently observed to be more prevalent in individuals with diabetes compared to the general population, and it can exacerbate glycaemic control, lipid abnormalities, weight gain, and overall cardiovascular-microvascular risk profiles. Reviews and consensus discussions highlight the bidirectional metabolic connections between thyroid hormones and insulin sensitivity, hepatic glucose production, and lipid metabolism, as well as diabetes-related alterations in the thyroid axis. Consequently, they advocate for a "low threshold" for thyroid assessment in diabetes, particularly among higher-risk subgroups. This study assessed many epidemiological and clinical factors, including diabetes type, age and sex distribution, prevalence and onset of hypothyroidism, clinical versus subclinical spectrum, medication usage, comorbidities, BMI and cholesterol levels, and clinical manifestations such as goitre. 1. Distribution by type of diabetes (Table 1) Present study findings • T2DM: 112/150 (74.7%) • T1DM: 38/150 (25.3%) • Male predominance overall (M 63.3%, F 36.7%) Comparison with similar studies The bulk of hospital-based research on thyroid function in diabetes mostly involve cohorts with Type 2 Diabetes Mellitus (T2DM), as T2DM represents the primary form of adultdiabetes encountered in general medicine and endocrine clinics. This isseen in several cross-sectional research examining the incidence of thyroid dysfunction and hypothyroidism in T2DM. Large cohorts of T2DM and mixed metabolic clinics consistently identify hypothyroidism/SCH as prevalent in persons with T2DM.[6,7] T1DM-specific research indicates a significant autoimmune overlap, particularly with autoimmune thyroid disease, where the frequency of thyroid dysfunction is notably high even among younger age cohorts. The Fremantle Diabetes Study Phase II revealed an overall baseline prevalence of thyroid illness in the high teens across several diabetes types, with no significant variations detected among them. This validates our inclusion of both T1DM and T2DM as clinically significant; nevertheless, the greater prevalence of T2DM in our sample corresponds with actual clinical demographics.[8] Our distribution is characteristic of an adult tertiary-care medicine/endocrinology environment, rendering our estimations most directly comparable to cohorts mostly consisting of T2DM patients. Age group and sex distribution (Table 2) Present study findings • Peak age group: 40–59 years (44%) • Next: 20–39 years (28%), 60–79 (26.7%) • Male predominance in all age groups • No significant association between age group and sex (p=0.912) Comparison with similar studies Numerous research on thyroid screening in T2DM predominantly indicate peak representation in middle age, mirroring the normal demographics of T2DM clinics. Thyroid dysfunction increases with age and is more prevalent in older populations; yet, clinic attendance often peaks in middle-aged people, akin to our 40–59 demographic clustering.[9] Research assessing predictors of thyroid dysfunction in T2DM patients often identifies feminine gender and advanced age as risk factors for thyroid dysfunction/hypothyroidism. A Pakistani cohort with Type 2 Diabetes Mellitus indicated a substantial correlation between thyroid dysfunction and both age group and female gender. Interpretation: The observed "middle-age predominance" likely indicates the demographic composition of the clinic's diabetes population, but disparities between sexes become more pronounced upon examination of thyroid status (as seen later in Table 10). Overall prevalence of hypothyroidism in diabetics (Table 3) Present study findings • Hypothyroidism (clinical + subclinical) in diabetics: 24/150 = 16.0% • Known hypothyroid at baseline: 8 • Newly detected at first visit: 15 • Newly detected on follow-up: 1 • No significant association between temporal occurrence groupings (p=0.194) Comparison with similar studies (overall burden) Our incidence of 16% is within a frequently observed range across several contexts: • In a substantial cohort of individuals with T2DM and hypertension (Talwalkar et al., 2017), the prevalence of hypothyroidism in T2DM was found to be around one quarter, which is higher than our result.[21] • Numerous T2DM clinical investigations indicate that the incidence of thyroid dysfunction ranges from the mid-teens to the high twenties, with hypothyroidism being the predominant anomaly.[44] • A Nigerian case-control research (Ezeani and Ogbonna 2024) reported a prevalence of thyroid dysfunction at 12.4% in individuals with T2DM, with hypothyroidism being the predominant majority—aligning closely with our estimate based on criteria and the inclusion of known cases.[10] • Historical screening efforts in diabetic populations shown that thorough testing identifies a significant percentage of previously undiagnosed thyroid disorders; Perros et al. documented newly identified thyroid conditions by screening, emphasising subclinical hypothyroidism (SCH) as the predominant new diagnosis.[11] Why our prevalence may be “moderate” (not very high) Variations among research are frequently elucidated by: 1. Population mix (T1DM vs T2DM, clinic vs community) 2. Definitions (TSH thresholds; whether isolated SCH included; whether “known hypothyroid on treatment” counted) 3. Iodine nutrition and background thyroid disease prevalence 4. Age and sex composition These factors are repeatedly discussed in reviews addressing thyroid– diabetes overlap.Our overall 16% corresponds with several studies indicating the prevalence of thyroid dysfunction/hypothyroidism among adolescents; it is lower than some cohorts where factors such as older age, higher female ratios, comorbidity burdens, or differing biochemical thresholds elevated the observed prevalence. Newly detected clinical vs subclinical hypothyroidism (Table 4) Present study findings Among 142 diabetics not previously known hypothyroid: • Newly detected hypothyroidism: 17/142 = 12.0% • Clinical (overt) hypothyroidism: 3 (2.1%) • Subclinical hypothyroidism: 14 (9.9%) Comparison with similar studies A prevailing theme is that subclinical hypothyroidism (SCH) is more prevalent than overt hypothyroidism in diabetes screening: • Perros et al. (annual screening) identified SCH as the most prevalent new diagnosis revealed during screening.[11] • In cohorts with Type 2 Diabetes Mellitus, Subclinical Hypothyroidism is often the predominant form of thyroid disease. • Reviews addressing T2DM and SCH particularly indicate increased SCH prevalence in T2DM and underscore the importance of screening. The observed rate of subclinical hypothyroidism (SCH) (~10%) aligns with the prevalence reported in certain complication-focused cohorts, but variations may arise due to selection criteria (e.g., nephropathy clinics) and definitional differences.[12] The preponderance of SCH in our findings aligns closely with documented trends, which is clinically significant since SCH may be asymptomatic yet remain linked to cardiometabolic risk. Which condition is detected first when both coexist (Table 5) Present study findings (n=24 with hypothyroidism + diabetes) • Diabetes first: 83.3% • Hypothyroidism first: 12.5% • Simultaneous detection: 4.2% • Association statistically significant (p=0.007) Comparison with similar studies Numerous clinic cohorts indicate that diabetes is frequently identified prior to the detection of thyroid dysfunction—not necessarily because to diabetes inducing hypothyroidism, but because: • Patients with diabetes get regular follow-ups, resulting in increased possibilities for thyroid testing. • Hypothyroidism, particularly subclinical hypothyroidism, may remain asymptomatic until aggressively checked. • Certain guidelines and practice patterns evaluate thyroid function selectively rather than regularly at the time of diabetes diagnosis, particularly in Type 2 Diabetes Mellitus, resulting in delayed identification of thyroid dysfunction. Earlier screening studies, like Perros et al., revealed that screening identifies previously undetected thyroid illness in individuals with diabetes.[11] Consequently, our discovery that diabetes frequently precedes the identification of hypothyroidism aligns with a "screening revealing latent disease" paradigm. The statistically substantial bias towards prioritising "diabetes first" endorses the practical proposal that thyroid screening should be proactively included into diabetic treatment protocols, rather than deferred until typical hypothyroid symptoms manifestGap between diagnoses among clinical hypothyroid + diabetes (Table 6) Present study findings For clinical hypothyroidism accompanied with diabetes: • Diabetes occurs first in 60% of cases, with a mean interval of around 9.8 years (range 1–21 years). • Hypothyroidism occurs first in 30% of cases, with a mean interval of around7.5 years (range 2–15 years). • Concurrent detection 10% Comparison with similar studies Literature frequently suggests that thyroid problems may manifest: • At baseline, especially in T1DM because to autoimmune overlap, and/or • During follow-up, particularly in patients with Type 2 Diabetes Mellitus and the elderly, where hypothyroidism may manifest or be identified at a later stage. Longitudinal data (Peters et al., 2020) from mixed diabetes cohorts indicate the emergence of thyroid illness throughout follow-up, even in initially euthyroid individuals, corroborating our finding of delayed onset/detection in certain patients.[8] Furthermore, studies characterise the relationships between diabetes and thyroid function as dynamic throughout time, affected by autoimmunity (T1DM), insulin resistance/weight (T2DM), age, and concomitant conditions. The 1–21 year gap range is clinically valid and underscores the importance of regular thyroid evaluations in diabetes patients rather than a singular examination. Oral antidiabetic drug (OAD) use and duration vs thyroid status (Tables 7 and 8) Present study findings (T2DM n=112) • OAD use overall: 94.6% • No significant association between thyroid status and OAD use (p=0.671) • OAD duration: • Normal: 7.4 years • SCH: 12.9 years • Clinical: 6.6 years No significant difference (p=0.205) Comparison with similar studies Most published studies on the prevalence of thyroid dysfunction in T2DM (Bukhari et al., 2022) indicate that thyroid status is not significantly influenced by the use of oral antidiabetic drugs (OADs). Instead, thyroid dysfunction is more consistently associated with female sex, age, duration of diabetes, and occasionally with poor glycaemic control or autoimmune markers, contingent upon the study design.[9] Our discovery that SCH patients exhibited a numerically extended OAD duration aligns with observations indicating that thyroid dysfunction may occur more frequently with prolonged diabetes duration in certain cohorts, often due to extended exposure time, increased screening opportunities, and shared metabolic risks. The absence of significance may indicate small subgroup numbers (notably, clinical hypothyroid T2DM n=7) and that OAD exposure serves as an indirect proxydiabetes duration and risk profile are more physiologically pertinent predictors than the binary classification of “OAD yes/no.” Age distribution of diabetics with coexisting hypothyroidism (Table 9) Present study findings (n=24) • Most hypothyroid diabetics clustered in 40–59 years • Predominantly T2DM • SCH is more common than clinical • Male predominance in hypothyroid subgroup counts (but see sex-specific proportions in Table 10) • No significant association between age group and thyroid status when analysed separately by sex Comparison with similar studies Numerous T2DM cohorts (Bukhari et al., 2022) indicate a greater prevalence of thyroid dysfunction correlated with advancing age and prolonged diabetes duration; nevertheless, the "peak incidence" often occurs in middle age if the underlying diabetic clinical population is most prevalent at that stage.[9] Furthermore, research on subclinical hypothyroidism (SCH) and microvascular problems (Kim et al., 2011) frequently indicates that SCH patients are typically older and have a prolonged duration of diabetes compared to their euthyroid counterparts.[13] The age clustering observed likely indicates both (1) the demographic composition of the diabetic community and (2) the epidemiological trend ofincreasing prevalence of thyroid dysfunction with advancing age and duration of illness. Type of diabetes × sex × SCH/clinical hypothyroidism (Table 10) Present study findings • Females had higher proportions: • Female SCH: 12.7% vs male SCH 7.4% • Female clinical hypothyroid: 10.9% vs male clinical 4.2% • Significant association of sex with thyroid dysfunction (p<0.05 in both sexes analyses) Comparison with similar studies A consistent and robust observation is the prevalence of females in hypothyroidism/subclinical hypothyroidism among diabetics: • In a Nigerian case-control study of Type 2 Diabetes Mellitus (T2DM), 75% of T2DM patients with thyroid dysfunction were female, with hypothyroidism being the predominant condition.[10] • In a cohort of Pakistani individuals with Type 2 Diabetes Mellitus, thyroid dysfunction had a substantial correlation with the female gender.[9] In a study on SCH-retinopathy among Korean patients with type 2 diabetes mellitus, the SCH group exhibited a greater proportion of women compared to the euthyroid group.[13] increasing prevalence of thyroid dysfunction with advancing age and duration of illness. Type of diabetes × sex × SCH/clinical hypothyroidism (Table 10) Present study findings • Females had higher proportions: • Female SCH: 12.7% vs male SCH 7.4% • Female clinical hypothyroid: 10.9% vs male clinical 4.2% • Significant association of sex with thyroid dysfunction (p<0.05 in both sexes analyses) Comparison with similar studies A consistent and robust observation is the prevalence of females in hypothyroidism/subclinical hypothyroidism among diabetics: • In a Nigerian case-control study of Type 2 Diabetes Mellitus (T2DM), 75% of T2DM patients with thyroid dysfunction were female, with hypothyroidism being the predominant condition.[10] • In a cohort of Pakistani individuals with Type 2 Diabetes Mellitus, thyroid dysfunction had a substantial correlation with the female gender.[44] In a study on SCH-retinopathy among Korean patients with type 2 diabetes mellitus, the SCH group exhibited a greater proportion of women compared to the euthyroid group.[48 The biological preponderance of females is credible, since autoimmune thyroid illness occurs more frequently in women, and female sex is a significant risk factor for hypothyroidism, even outside diabetic cohorts.[14] Our notable sexual correlation is among the most consistent alignments with worldwide literature and advocates for focused screening, particularly in women with diabetes.Clinical symptom profile of hypothyroidism in diabetics (Table 12) Present study findings (clinically hypothyroid n=8) Most common symptoms: • Weakness/lethargy 100% • Dry skin 75% • Cold intolerance and weight gain 62.5% each • Decreased sweating/paraesthesia 50% • Constipation/hoarseness 37.5% Comparison with similar studies Numerous studies on diabetes-thyroid prevalence emphasise biochemical detection over comprehensive symptom frequency, as subclinical hypothyroidism predominates and frequently presents asymptomatically. Nonetheless, symptomatology in overt hypothyroidism typically aligns with traditional presentations of the condition, including tiredness, cold sensitivity, weight gain, constipation, and dermatological alterations. Comprehensive analyses of thyroid abnormalities in diabetes highlight that clinical hypothyroidism can aggravate dyslipidaemia andinsulin resistance, with symptoms that may be vague and overlap with those of diabetes (such as tiredness, weight fluctuations, and neuropathic feelings).[18,49] The distribution of our symptoms is clinically consistent. Significantly, overlapping symptoms such as weariness and paraesthesia may be erroneously ascribed to diabetes, reinforcing the necessity for biochemical testing instead of relying solely on symptom-based identification. Clinical signs in clinically hypothyroid diabetics (Table 13) Present study findings • Delayed ankle jerk relaxation 87.5% • Coarse skin and periorbital puffiness 62.5% each • Slow speech/cold skin 50% • Bradycardia 37.5% • Goitre 25% Comparison with similar studies Similar to symptoms, several prevalence studies fail to quantify signs; yet, the sign pattern is characteristic of overt hypothyroidism. In diabetic populations, the diagnostic problem lies in the potential oversight of mild indications, whereas subclinical hypothyroidism may present no symptoms. Reviews highlight that nrecognized thyroid dysfunction is prevalent and that standard clinical examinations may overlook several cases of subclinical hypothyroidism (SCH).[11]Our clinical sign profile reinforces the diagnostic validity of overt patients and offers a useful bedside “red flag” set for doctors assessing diabetes. Goitre prevalence by thyroid status (Table 14; Figure 8) Present study findings • Overall goitre: 5.3% • Goitre prevalence: • Normothyroid: 1.6% • SCH: 21.4% • Clinical hypothyroid: 30% • Statistically significant association (p<0.001) Comparison with similar studies The prevalence of goitre significantly fluctuates according to iodine levels, the incidence of autoimmune thyroiditis, and the diagnostic technique employed (palpation versus ultrasonography). Numerous research on diabetes and thyroid function indicate the frequency of thyroid dysfunction without specifying goitre, however the associations with autoimmune thyroid disease are well documented, particularly in Type 1 Diabetes Mellitus and in women.[50] The robust correlation between goitre and hypothyroid conditions is clinically anticipated, since persistent TSH stimulation, especially in autoimmune thyroiditis, may lead to widespread enlargement. The significance (p<0.001) indicates that goitre is a substantial clinical correlate of thyroid dysfunction in our cohort, despite the fact that some patients with subclinical hypothyroidism in other contexts may not present with goitre. Interpretation: In our context, palpation-detected diffuse goitre serves as a valuable diagnostic indicator, particularly when combined with biochemical screening. Diabetic complications vs thyroid status (Table 16) Present study findings • No statistically significant link exists between thyroid dysfunction and complications in both Type 1 and Type 2 Diabetes Mellitus overall. • A key anomaly in our p-values is that nephropathy with T2DM exhibited p=0.001, indicating a robust connection signal in our table, but the majority of other outcomes were non-significant. Comparison with similar studies (microvascular risk) The worldwide research is varied but increasingly indicates that subclinical hypothyroidism (SCH) may be linked to specific microvascular problems, including nephropathy and severe retinopathy, contingent upon confounder correction and cohort characteristics: Nephropathy • Furukawa et al. (Japan, T2DM) identified a prevalence of SCH at 8.7% and noted that the SCH cohort exhibited a greater frequency of nephropathy; multivariate analysis indicated that SCH was independently correlated with diabetic nephropathy (OR ~3.5).[12] • Additional research investigates thyroid function in diabetic nephropathy and indicates correlations between diminished thyroid hormone levels and the severity of nephropathy. Retinopathy • Kim et al. (Korea) showed a greater frequency of severe diabetic retinopathy in individuals with subclinical hypothyroidism (SCH) compared to those who are euthyroid, with SCH remaining an independent association after correction.[13]Neuropathy • Reviews and some observational studies indicate that subclinical hypothyroidism (SCH) may be associated with the severity of diabetic peripheral neuropathy in specific groups, but heterogeneity is prevalent. Reconciling our “mostly non-significant” pattern Our ultimate result of "no significant correlation" may be affected by: • Limited sample sizes in thyroid dysfunction subgroups, particularly when differentiating between T1DM/T2DM and SCH/clinical conditions. • Numerous comparisons across various difficulties (insufficient power per cell) • Case-mix and the definition/ascertainment of complexities Significantly, our table demonstrates a robust relationship signal between nephropathy and T2DM (p=0.001), which aligns well with the nephropathy-SCH link described by Furukawa and colleagues. In a comprehensive analysis, it is pertinent to note that although the majority of problems did not exhibit statistical linkage (perhaps owing to insufficient power), T2DM nephropathy revealed a substantial correlation with thyroid dysfunction in our sample, consistent with existing literature. The most prudent conclusion is "generally mixed association with limited strength," although it is crucial to emphasise that the connections between nephropathy and SCH possess biological plausibility and are supported by existing literature, with our data indicating a similar trend. BMI, triglycerides, cholesterol across groups (Table 17) Present study findings • Elevated BMI, triglycerides, and cholesterol levels were seen in hypothyroid diabetics, particularly in those with Type 2 Diabetes Mellitus and clinical hypothyroidism; however, these findings were not statistically significant. Comparison with similar studies The correlation between thyroid dysfunction and dyslipidaemia in diabetes is physiologically anticipated (hypothyroidism leads to elevated LDL-C and triglycerides in numerous people); nonetheless, diabetes significantly influences lipid levels, and factors such as statin usage, length of diabetes, and obesity may obscure the findings. Numerous studies indicate that subclinical hypothyroidism in type 2 diabetes mellitus is linked to exacerbated cardiovascular risk factors and/or dyslipidaemia: • Furukawa et al. observed an elevated frequency of dyslipidaemia in the SCH cohort. • In the Korean SCH-retinopathy investigation, BMI exhibited no significant differences across groups, indicating that BMI connections are inconsistent among cohorts. • Reviews addressing SCH in T2DM examine its possible correlation with comorbidities and metabolic risk, indicating that variations in lipid levels and BMI may be present, albeit minor and potentially confounding. Why our lipid/BMI differences may not be significant • Limited subgroup sizes (notably T1DM with thyroid dysfunction and T2DM with clinical hypothyroidism) • Unstratified background lipid-lowering treatment • The effects of glycaemic management and duration may surpass the influence of thyroid function. • Variability in single time-point measurements Our tendency is clinically congruent, and the lack of significance likely indicates insufficient power and confounding factors. It continues to facilitate meticulous lipid risk control in diabetics with thyroid dysfunction. Implications for screening and follow-up in our cohort Our data show: • A significant overall burden of hypothyroidism (16%) • Prevalence of SCH in new diagnoses (Table 4). Diabetes is generally identified initially (Table 5) • Predominance of females in thyroid dysfunction (Table 10) • Goitre is significantly correlated with hypothyroid state (Table 14) • A troubling indicator of nephropathy in Type 2 Diabetes Mellitus (Table 16) This combination reinforces the practical premise that screening detects otherwise overlooked thyroid disease, reflecting traditional yearly screening recommendations for diabetics. Simultaneously, current discourse indicates that recommendations vary among systems and that routine thyroid screening for T2DM is not consistently included into all diabetes guidelines; this discrepancy has been explicitly addressed in the literature, underscoring the necessity for context-specific methods. Recent thorough evaluations persist in highlighting screening and treatment implications within diabetic populations.[15,16,17] Pragmatic approach suggested by our findings (discussion framing): • Conduct screening at baseline for female diabetics with prolonged diabetes duration, goitre, unexplained dyslipidaemia or weight increase, or microvascular complications, particularly nephropathy. • Consider periodic re-evaluation, since certain instances have manifested subsequently (follow-up detection within our cohort; longitudinal cohort data corroborates the emergence of incident thyroid illness). Clinical and public health implications: The trend of "diabetes diagnosed first" alongside a significant incidence of newly identified hypothyroidism suggests that passive, symptom-based detection will overlook a fraction of patients, especially subclinical hypothyroidism (SCH). Your statistics therefore substantiate the operational significance of thyroid testing within diabetes management protocols. Significantly, data from foundational screening studies in diabetes indicate that yearly or periodic assessments identify previouslyunrecognised thyroid illness, hence endorsing the principle of repeated testing over a singular review. Future directions to strengthen evidence from our setting To expand upon our current findings, more research might: • Assess anti-TPO antibodies and conduct thyroid ultrasonography in certain instances to differentiate autoimmune thyroiditis from alternative aetiologies of goitre/hypothyroidism. • Incorporate glycaemic control indicators (HbA1c), statin use, and diabetes duration as factors in multivariate models to more effectively delineate the impact of thyroid status on comorbidities and lipid profiles. • Employ a prospective follow-up design to assess whether the treatment of hypothyroidism/subclinicalhypothyroidism enhances lipid parameters, microvascular outcomes, or quality-of-life indicators in individuals with diabetes. These enhancements will refine causal inference and facilitate the formulation of context-specific screening and care methods pertinent to your patient demographic. Strengths and limitations Strengths • Incorporation of both Type 1 Diabetes Mellitus (T1DM) and Type 2 Diabetes Mellitus (T2DM) together with stratified analysis • Differentiation between established and newly identified thyroid disease • Clinical correlation (symptoms, signs, goitre) in conjunction with biochemical classification • Correlation of attempted complications Limitations Subgroup sizes diminish following classification (T1DM thyroid subgroups; clinical hypothyroid subsets), constraining the statistical power for comparisons of complications and cholesterol levels. • Undisclosed potential confounders include statin medication, thyroid antibody status (anti-TPO), iodine status, and HbA1c/duration distributions within thyroid groups. • The cross-sectional design of several connections restricts causal inference; some outcomes may need prospective follow-up. These constraints are extensively recognised in the literature about the thyroid-diabetes relationship.

Hypothyroidism, especially subclinical hypothyroidism, frequently coexists in individuals with diabetes mellitus. This study reveals that a considerable percentage of diabetic individuals possess previously undiscovered thyroid dysfunction, with diabetes mellitus frequently occurring before the identification of hypothyroidism. The female sex and the presence of goitre were substantially correlated with thyroid malfunction, whereas subclinical hypothyroidism was identified as the most prevalent newly diagnosed anomaly.

While the correlation between thyroid dysfunction and the majority of diabetic complications was not statistically significant, the identified relationship with diabetic nephropathy in Type 2 diabetes mellitus, along with the negative trends in metabolic parameters, implies a possible contributory role of hypothyroidism in exacerbating cardiometabolic risk. The convergence of clinical characteristics between diabetes and hypothyroidism underscores the necessity for biochemical screening instead of only depending on symptoms.

These data indicate that frequent monitoring of thyroid function in patients with diabetes mellitus, especially in women, individuals with prolonged illness duration, and those exhibiting suggestive clinical characteristics, is warranted. Timely recognition and effective therapy of thyroid dysfunction may enhance metabolic regulation, refine risk assessment, and promote holistic care for individuals with diabetes mellitus.

Conflict of Interest:None

Funding Support;Nil

1.Jali MV, Kambar S, Jali SM, Pawar N, Nalawade P. Prevalence of thyroid dysfunction among type 2 diabetes mellitus patients. Diabetes Metab Syndr 2017;11 Suppl 1:S105–8.

2.Nair A, Jayakumari C, Jabbar PK, Jayakumar RV, Raizada N, Gopi A, et al.Prevalence and Associations of Hypothyroidism in Indian Patients with Type 2 Diabetes Mellitus. J Thyroid Res 2018;2018:5386129.

3.Elgazar EH, Esheba NE, Shalaby SA, Mohamed WF. Thyroid dysfunction prevalence and relation to glycemic control in patients with type 2 diabetes mellitus. Diabetes Metab Syndr 2019;13(4):2513–7.

4.Ogbonna S, Ezeani I, Okafor C, Chinenye S. Association between glycemic status and thyroid dysfunction in patients with type 2 diabetes mellitus. Diabetes Metab Syndr Obes2019;12:1113–22.

5.Ward RJ, Heald AH, Ogunmekan S, Fryer AA, Duff CJ. Should we be screening for thyroid dysfunction in patients with type 2 diabetes mellitus? Br J Gen Pract 2018;68(667):94–5.

6.Talwalkar P, Deshmukh V, Bhole M. Prevalence of hypothyroidism in patients with type 2 diabetes mellitus and hypertension in India: a cross-sectional observational study. Diabetes Metab Syndr Obes2019;12:369–76.

7.Mehalingam V, Sahoo J, Bobby Z, Vinod KV. Thyroid dysfunction in patients with type 2 diabetes mellitus and its association with diabetic complications. J Family Med Prim Care 2020;9(8):4277–81.

8.Peters KE, Chubb SAP, Bruce DG, Davis WA, Davis TME. Prevalence and incidence of thyroid dysfunction in type 1 diabetes, type 2 diabetes and latent autoimmune diabetes of adults: The Fremantle Diabetes Study Phase II. Clin Endocrinol (Oxf) 2020;92(4):373–82.

9.Bukhari SI, Ali G, Memom MY, Sandeelo N, Alvi H, Talib A, et al. Prevalence and predictors of thyroid dysfunction amongst patients with Type 2 diabetes mellitus in Pakistan. J Family Med Prim Care 2022;11(6):2739–43.

10.Ezeani IU, Ogbonna SU. Burden of Thyroid Dysfunction Among Type 2 Diabetes Mellitus Patients in South East Nigeria with Emphasis on its Prevalence and Pattern of Presentation: A Case-Controlled Study. West Afr J Med 2024;41(2):118–25.

11.Perros P, McCrimmon RJ, Shaw G, Frier BM. Frequency of thyroid dysfunction in diabetic patients: value of annual screening. Diabet Med 1995;12(7):622–7.

12.Furukawa S, Yamamoto S, Todo Y, Maruyama K, Miyake T, Ueda T, et al.Association between subclinical hypothyroidism and diabetic nephropathy in patients with type 2 diabetes mellitus. Endocr J 2014;61(10):1011–8.

13.Kim BY, Kim CH, Jung CH, Mok JO, Suh KI, Kang SK. Association between subclinical hypothyroidism and severe diabetic retinopathy in Korean patients with type 2 diabetes. Endocr J 2011;58(12):1065–70.

14.Hage M, Zantout MS, Azar ST. Thyroid disorders and diabetes mellitus. J Thyroid Res 2011;2011:439463.

15.Biondi B, Kahaly GJ, Robertson RP. Thyroid Dysfunction and Diabetes Mellitus: Two Closely Associated Disorders. Endocr Rev 2019;40(3):789–824.

16.Kalra S, Aggarwal S, Khandelwal D. Thyroid Dysfunction and Type 2 Diabetes Mellitus: Screening Strategies and Implications for Management. Diabetes Ther 2019;10(6):2035–44.

17.Palit T, Heald AH, Fryer AA, Duff CJ. Screening for thyroid disease in patients with type 2 diabetes mellitus: An evaluation of current practice. Ann Clin Biochem 2020;57(3):242–5.