Coronary heart disease is a leading cause of death and disability-adjusted life years in India, according to studies conducted by the World Health Organisation and the Global Burden of Disease. Coronary heart disease (CHD) has been much more common in India during the last 60 years, with estimates ranging from 1% in urban areas to 9%-10% and 4%-6% in rural areas. A considerable number of persons have Non-ST Elevated Myocardial Infarction (NSTEMI) compared to ST Elevated Myocardial Infarction (STEMI), and myocardial infarction, the most common form of coronary heart disease, is responsible for approximately 15% of yearly death. Myocardial infarction is more common in men than in women of any age group.

Diabetes is known to greatly increase the chance of heart diseases, such as heart attacks[1,2]. Significantly, 25 years ago, Haffner et al. [3] suggested that the risk of myocardial infarction (MI) was equal for a patient with diabetes and a patient without diabetes who had a prior personal history of MI, a finding later corroborated by additional studies [4].

Acute myocardial infarction (AMI), commonly referred to as a heart attack, is a predominant cause of mortality and morbidity globally. The World Health Organisation (WHO) states that cardiovascular disease is an escalating health concern that is not transmissible between individuals. In India, the prevalence of ischaemic heart disease (IHD) among adults is approximately 97 per 1,000 individuals in urban areas and 27 per 1,000 in rural regions, as determined by medical assessments and ECG findings.

Diabetes impacts approximately 6% of the population in the United States and is present in over 30% of individuals treated for cardiac issues[5]. Individuals with diabetes are widely recognized to possess an elevated mortality risk during a myocardial infarction and experience increased health complications post-event[6-8]. The risk of coronary heart disease (CHD) in those with diabetes is increased by approximately two to four times. They face a twofold risk of mortality quickly following a myocardial infarction, even when accounting for other cardiovascular disease variables. [9, 10] constitutes a numerical pair.

Acute myocardial infarction (AMI) is the leading cause of death in both sexes. Age, gender, and diabetes are recognized risk factors affecting survival. Reports reveal that women have a higher 30-day mortality rate post-AMI compared to men. Furthermore, certain studies indicate that increased early post-myocardial infarction death rates may be limited to younger women, who represent a unique cohort with particular risk factors and pathophysiological traits. [11].

In recent years, the prevalence of cardiovascular disease in Asia has escalated, with forecasts suggesting it may attain critical levels due to increasing rates of smoking, alcohol consumption, obesity, and diabetes. [12,13].

Approximately 20% of persons with acute myocardial infarction and no previous diabetes diagnosis demonstrate elevated glucose levels post-hospitalization [14-16]. This intensifies the mortality rates among individuals with AMI. This association is thought to arise from an undiagnosed diabetes issue. The increased sugar levels may stem from the stress related to the acute myocardial infarction. [17].

The objective of this study is to examine the prevalence and outcomes of diabetic patients experiencing acute myocardial infarction.

This research was carried out at the Prathima Relief Institute of Medical Sciences in Arepally, Warangal from 2022 to 2023. A total of 224 individuals with myocardial infarction admitted to our hospital were included in the study. Informed consent was obtained from all patients before their inclusion in the trial. All patients met the diagnostic criteria for acute myocardial infarction.

Comprehensive demographic data, including age, gender, blood pressure, smoking and alcohol consumption, as well as previous clinical and medical history, were documented for all patients. Participants with epilepsy, subdural hematoma, subarachnoid hemorrhage, or any other neurological condition that could affect HbA1c levels were excluded from the study.

Blood samples were collected from the patients to evaluate random blood glucose and HbA1c concentrations. Cholesterol and triglyceride levels were assessed.

Patients with a prior diagnosis or random blood sugar >200 mg/dL, fasting glucose >126 mg/dL, and postprandial glucose >200 mg/dL were categorized as having diabetes. On the fifth day, if glucose levels were below 126 mg/dl, the individual was categorized as nondiabetic.

Newly diagnosed diabetics were categorized as such if they demonstrated elevated glucose levels during their whole hospital stay. Their confirmation was substantiated after 2-3 months of reassessing the glucose levels during the patient's follow-up appointment.

Patients without a prior diabetes diagnosis and presenting fasting blood glucose levels <126 mg/dl were categorized as non-diabetic. All patients displaying normal blood glucose levels during their hospitalization but who could not undergo further evaluation owing to early death or other issues were classified as non-diabetic.

Data Analysis:

We employed the Statistical Package for the Social Sciences (SPSS version 11.0, Chicago). Results are expressed as mean ± standard deviation (SD) unless stated differently. The student's t-test was applied to assess the significance of differences between the mean values of two continuous variables, whereas the Mann-Whitney test was employed for nonparametric distributions. A chi-square analysis was performed to assess the variations in proportions of categorical variables between two or more groups. The Fisher exact test (2-tailed) was utilized in 2x2 tables instead of the chi-square test, especially when the sample size was constrained. A one-way analysis of variance (ANOVA) was employed to compare multiple group means and determine the presence of significant differences among them. Multivariate stepwise regression analysis was performed to identify drivers of in-hospital outcomes for acute myocardial infarction (AMI). A p-value below 0.05 was considered significant.

A total of 224 patients who were hospitalized due to acute myocardial infarction between 2022 and 2023 were included in the analysis. Among these, 112 patients were diagnosed with diabetes mellitus, while 102 patients did not have this condition. The average age of patients was 60.3 ± 10.8 years; 112 (54%) had diabetes mellitus, 75 (37.5%) had hypertension, and 68 (27.5%) had hypercholesterolemia; 59.3% had a familial history of coronary artery disease, 66 (36.5%) were current smokers, and 52 (25.5%) were former smokers; 90 had a history of prior acute myocardial infarction, and 10 had undergone coronary artery bypass grafting.

Table 1 Represents the Baseline Clinical Characteristics of the patients.

A higher number of diabetic patients experienced AMI compared to those without diabetes, regardless of gender; the proportion of women with both DM and AMI was greater than that of men (67.5% vs 47.3%; P < .0001). Diabetic patients were more frequently postmenopausal women (32.6% vs. 17.3%; P < .01) and exhibited a higher prevalence of hypertension and hypercholesterolemia while being less likely to be current smokers compared to nondiabetic patients (Table 1). No significant differences were seen between the two groups concerning the age of presentation and the presence of a family history of coronary artery disease, prior myocardial infarction, and coronary artery bypass grafting. (Table 2).

Table 2 Represents the Laboratory profile of Patients Presented With AMI.

Table 3  Represents the various modes of therapy.

Table 3 illustrates the different therapeutic modalities, such as bleeding and stroke, comparing the two groups. No significant differences were seen between the groups for thrombolytic therapy, aspirin, and beta-blockers, except for a markedly greater incidence of ACE inhibitor usage in the diabetic patient cohort (P = .001).

A logistic regression study indicated that age (OR 1.03, 95% CI 1.01-1.04, P = .001) and smoking (OR 2.09, 95% CI 1.29-3.40, P = .003) were significant and independent predictors of death in diabetic individuals with acute myocardial infarction (AMI). Aspirin (OR 2.29, 95% CI 1.86-2.90, P = .002) and β-blocker use (OR 1.75, 95% CI 1.21-2.51, P = .0001) correlated with a decreased mortality risk. (Table 4).

Table 4 Represents the Univariate and Multivariate Predictors of In-hospital Mortality in Diabetic Patients who Presented with Acute Myocardial Infarction (AMI

The Framingham study indicates a higher incidence of cardiac disease in diabetic patients and a worse prognosis compared to non-diabetic individuals. The mortality rate was higher in males than in women among diabetic patients compared to non-diabetic patients.[17] Diabetic patients who experience myocardial infarction are at a higher risk for complications compared to non-diabetic patients, including recurrent infarction, cardiogenic shock, atrioventricular and intraventricular conduction abnormalities, chronic congestive heart failure, and myocardial rupture.[18,19].

The mean age of the patients in our study was 60.3 years, with a standard deviation of 10.8 years; 112 patients (54%) had diabetes, 37.5% had hypertension, and 68 patients (27.5%) had hypercholesterolemia; 59.3% of these patients had a family history of coronary artery disease (CAD); 66 patients (36.5%) were current smokers, and 52 patients (25.5%) were former smokers; 90 patients had a history of previous acute myocardial infarction (AMI), and ten patients had a history of coronary artery bypass surgery (CABG).

The prevalence of diabetes mellitus was greater than that of other recognized cardiovascular risk factors, such as hypertension and hypercholesterolemia. The prevalence of diabetes mellitus (DM) in patients with acute coronary syndrome (ACS) varies between 18% and 21%, according to current multinational registries.[20,21]. The Euro Heart Survey on diabetes and cardiovascular disease, which recruited patients from 25 countries, found that 22% of patients abruptly hospitalized for coronary artery disease had unrecognized diabetes mellitus. Consequently, the overall prevalence of diabetes mellitus among individuals with acute coronary syndrome appears to be approximately 45%.[22]

In our study, the prevalence of diabetes mellitus in patients with acute myocardial infarction is 54%, which exceeds the figures reported by Tenerzetal (25%) in Sweden, Lowel et al. (21%) in Germany, and Gandhi et al. (17%) in Olmsted County, Minnesota.[25] The detrimental impact of diabetes mellitus on long-term survival following acute myocardial infarction was independent of other cardiovascular disease risk factors, myocardial infarction severity, and treatment modalities. Franklin et al. [20] discovered that, in contrast to instances devoid of a diabetes mellitus history, roughly 25% of cases exhibited such a history.

The prevalence rises with age, exceeding 14% among individuals aged 41 to 48 and surpassing 27% in those aged 50.[26]

Yusuf et al. ascribed the elevated prevalence of cardiovascular disease in developing nations to the rising incidence of atherosclerotic conditions, potentially resulting from urbanization.

Urbanization leads to a significant rise in the consumption of energy-dense foods and a decline in energy expenditure due to reduced physical activity, resulting in increased risk factors, as demonstrated in our study. From 1990 to 2020, CAD mortality is projected to be significantly higher in developing nations (121% in women and 127% in men) compared to developed countries (29% in women and 48% in men).

The present investigation revealed no significant difference between diabetic and non-diabetic patients regarding preceding AMI and in-hospital acute medical care, except for higher utilization of ACEI in diabetic patients (P = .001). The death rate was not significantly elevated in the diabetes cohort. Aspirin (OR 2.29, 95% CI 1.86-2.90, P = .002) and β blocker use (OR 1.75, 95% CI 1.21-2.51, P = .0001) were independently correlated with decreased mortality risk. We noted markedly increased creatine kinase (CK) activity in the non-diabetic cohort relative to the diabetic patients (P = 0.006); nonetheless, the death rates in both groups were high (18.1% vs 15.4%) and did not differ substantially. The prognosis for diabetic individuals with acute coronary syndrome (ACS) and normal cardiac markers is similar to that of non-diabetic patients with raised cardiac markers, indicating a need for urgent treatment. [27] Reports suggest that high-risk patients, including those with diabetes mellitus, have lesser increases in enzymes following acute myocardial infarction, although having a worse prognosis.[28]

By our results, diabetic women have a much worse prognosis, demonstrating an almost twofold increase in mortality relative to diabetic men (15% vs 23.6%; P < .001). Survival and recurrent cardiovascular events in diabetes patients post-AMI are closely associated with the following risk factors: degree of global pump malfunction after AMI, multivessel coronary artery disease, the diabetic haematologic environment, and diabetic autonomic neuropathy [29-31]

The incidence of diabetes mellitus in patients presenting with acute myocardial infarction within a geographically specified population in the developing world is significant. The prevention of diabetes mellitus requires increased focus on this demographic.

1. Narayan KV, Boyle JP, Thompson TJ, Sorensen SW, Williamson DF. Lifetime risk for diabetes mellitus in the United States. Jama. 2003 Oct 8;290(14):1884-90.
2. Franco OH, Steyerberg EW, Hu FB, Mackenbach J, Nusselder W. Associations of diabetes mellitus with total life expectancy and life expectancy with and without cardiovascular disease. Archives of internal medicine. 2007 Jun 11;167(11):1145-51.
3. Haffner SM, Lehto S, Rönnemaa T, Pyörälä K, Laakso M. Mortality from coronary heart disease in subjects with type 2 diabetes and in nondiabetic subjects with and without prior myocardial infarction. New England journal of medicine. 1998 Jul 23;339(4):229-34.
4. Malmberg K, Yusuf S, Gerstein HC, Brown J, Zhao F, Hunt D, Piegas L, Calvin J, Keltai M, Budaj A, Investigators FT. Impact of diabetes on long-term prognosis in patients with unstable angina and non–Q-wave myocardial infarction: results of the OASIS (Organization to Assess Strategies for Ischemic Syndromes) Registry. Circulation. 2000 Aug 29;102(9):1014-9.
5. Jacoby RM, Nesto RW. Acute myocardial infarction in the diabetic patient: pathophysiology, clinical course and prognosis. Journal of the American college of cardiology. 1992 Sep 1;20(3):736-44.
6. Aronson D, Rayfield EJ, Chesebro JH. Mechanisms determining course and outcome of diabetic patients who have had acute myocardial infarction. Annals of internal medicine. 1997 Feb 15;126(4):296-306.
7. Kannel WB, McGee DL. Diabetes and glucose tolerance as risk factors for cardiovascular disease: the Framingham study. Diabetes care. 1979 Mar 1;2(2):120-6.
8. Woodfield SL, Lundergan CF, Reiner JS, Greenhouse SW, Thompson MA, Rohrbeck SC, Deychak Y, Simoons ML, Califf RM, Topol EJ, Ross AM. Angiographic findings and outcome in diabetic patients treated with thrombolytic therapy for acute myocardial infarction: the GUSTO-I experience. Journal of the American College of Cardiology. 1996 Dec;28(7):1661-9.
9. Hochman JS, Tamis JE, Thompson TD, Weaver WD, White HD, Van de Werf F, Aylward P, Topol EJ, Califf RM. Sex, clinical presentation, and outcome in patients with acute coronary syndromes. New England Journal of Medicine. 1999 Jul 22;341(4):226-32.
10. Berger JS, Elliott L, Gallup D, Roe M, Granger CB, Armstrong PW, Simes RJ, White HD, Van de Werf F, Topol EJ, Hochman JS. Sex differences in mortality following acute coronary syndromes. Jama. 2009 Aug 26;302(8):874-82.
11. Vaccarino V, Parsons L, Every NR, Barron HV, Krumholz HM. Sex-based differences in early mortality after myocardial infarction. New England journal of medicine. 1999 Jul 22;341(4):217-25.
12. Kosiborod M, Inzucchi SE, Krumholz HM, Xiao L, Jones PG, Fiske S, Masoudi FA, Marso SP, Spertus JA. Glucometrics in patients hospitalized with acute myocardial infarction: defining the optimal outcomes-based measure of risk. Circulation. 2008 Feb 26;117(8):1018-27.
13. Kosiborod M, Rathore SS, Inzucchi SE, Masoudi FA, Wang Y, Havranek EP, Krumholz HM. Admission glucose and mortality in elderly patients hospitalized with acute myocardial infarction: implications for patients with and without recognized diabetes. Circulation. 2005 Jun 14;111(23):3078-86.
14. Capes SE, Hunt D, Malmberg K, Gerstein HC. Stress hyperglycaemia and increased risk of death after myocardial infarction in patients with and without diabetes: a systematic overview. The Lancet. 2000 Mar 4;355(9206):773-8.
15. Bartnik M, Ryden L, Ferrari R, Malmberg K, Pyörälä K, Simoons M, Standl E, Soler-Soler J, Öhrvik J. The prevalence of abnormal glucose regulation in patients with coronary artery disease across Europe: The Euro Heart Survey on diabetes and the heart. European heart journal. 2004 Nov 1;25(21):1880-90.
16. Norhammar A, Tenerz Å, Nilsson G, Hamsten A, Efendíc S, Rydén L, Malmberg K. Glucose metabolism in patients with acute myocardial infarction and no previous diagnosis of diabetes mellitus: a prospective study. The Lancet. 2002 Jun 22;359(9324):2140-4.
17. Rytter L, Troelsen S, Beck-Nielsen H. Prevalence and mortality of acute myocardial infarction in patients with diabetes. Diabetes care. 1985 May 1;8(3):230-4.
18. Stone PH, Muller JE, Hartwell T, York BJ, Rutherford JD, Parker CB, Turi ZG, Strauss HW, Willerson JT, Robertson T, Braunwald E. The effect of diabetes mellitus on prognosis and serial left ventricular function after acute myocardial infarction: contribution of both coronary disease and diastolic left ventricular dysfunction to the adverse prognosis. Journal of the American College of Cardiology. 1989 Jul 1;14(1):49-57.
19. Czyżk A, Królewski AS, Szabłowska S, Alot A, Kopczyński J. Clinical course of myocardial infarction among diabetic patients.
20. Franklin K, Goldberg RJ, Spencer F, Klein W, Budaj A, Brieger D, Marre M, Steg PG, Gowda N, Gore JM, GRACE investigators. Implications of diabetes in patients with acute coronary syndromes: the Global Registry of Acute Coronary Events. Archives of Internal Medicine. 2004 Jul 12;164(13):1457-63.
21. Hasdai D, Behar S, Wallentin L, Danchin N, Gitt AK, Boersma E, Fioretti PM, Simoons ML, Battler A. A prospective survey of the characteristics, treatments and outcomes of patients with acute coronary syndromes in Europe and the Mediterranean basin. The Euro Heart Survey of Acute Coronary Syndromes (Euro Heart Survey ACS). European heart journal. 2002 Aug 1;23(15):1190-201.
22. Bartnik M. Glucose regulation and coronary artery disease. Studies on prevalence, recognition and prognostic implication. Karolinska Institutet, Stockholm. 2005.
23. Tenerz Å, Lönnberg I, Berne C, Nilsson G, Leppert J. Myocardial infarction and prevalence of diabetes mellitus. Is increased casual blood glucose at admission a reliable criterion for the diagnosis of diabetes?. European heart journal. 2001 Jul 1;22(13):1102-10.
24. Löwel H, Koenig W, Engel S, Hörmann A, Keil U. The impact of diabetes mellitus on survival after myocardial infarction: can it be modified by drug treatment? Results of a population-based myocardial infarction register follow-up study. Diabetologia. 2000 Feb;43:218-26.
25. Gandhi GY, Roger VL, Bailey KR, Palumbo PJ, Ransom JE, Leibson CL. Temporal trends in prevalence of diabetes mellitus in a population-based cohort of incident myocardial infarction and impact of diabetes on survival. InMayo Clinic Proceedings 2006 Aug 1 (Vol. 81, No. 8, pp. 1034-1040). Elsevier.
26. Okunoye G, Konje J, Lindow S, Perva S. Gestational diabetes in the Gulf region: streamlining care to optimise outcome. Journal of Local and Global Health Science. 2015 May 20;2015(1):2.
27. Fazel R, Fang J, Kline-Rogers E, Smith DE, Eagle KA, Mukherjee D. Prognostic value of elevated biomarkers in diabetic and non-diabetic patients admitted for acute coronary syndromes. Heart. 2005 Mar 1;91(3):388-90.
28. Taylor GJ, Moses HW, Katholi RE, Korsmeyer C, Kolm P, Dove JT, Mikell FL, Sutton JM, Wellons HA, Schneider JA. Six-year survival after coronary thrombolysis and early revascularization for acute myocardial infarction. The American journal of cardiology. 1992 Jul 1;70(1):26-30.
29. Jaffe AS, Spadaro JJ, Schechtman K, Roberts R, Geltman EM, Sobel BE. Increased congestive heart failure after myocardial infarction of modest extent in patients with diabetes mellitus. American heart journal. 1984 Jul 1;108(1):31-7.
30. Svensson AM, Abrahamsson P, McGuire DK, Dellborg M. Influence of diabetes on long‐term outcome among unselected patients with acute coronary events. Scandinavian Cardiovascular Journal. 2004 Jan 1;38(4):229-34.
31. El-Menyar AA. Dysrhythmia and electrocardiographic changes in diabetes mellitus: pathophysiology and impact on the incidence of sudden cardiac death. Journal of Cardiovascular Medicine. 2006 Aug 1;7(8):580-5.