COMPARING CARDIOVASCULAR EVENTS IN SULFONYLUREA VS. METFORMIN USERS: A RETROSPECTIVE STUDY

Abstract

Background: Diabetes mellitus (T2DM) impacts health at the global level, and the risks associated with CVD stacks onto the burden posed by T2DM. CVD risks and impacts rank the highest as morbidity and mortality factors in populations with diabetes. Among the antidiabetic drugs, particularly between metformin and sulfonylureas, the cardiovascular safety is still under research. This study focuses on evaluating cardiovascular events in T2DM patients who are on metformin therapy and those who are on sulfonylureas therapy in a tertiary care facility in Pakistan.

Methods: This retrospective observational study focuses on 450 T2DM patients. Only those patients, on monotherapy metformin or sulfonylureas for 6 months or more, were included. From the patients’ medical records, and according to the study framework, data were extracted on sociodemographic variables, the duration of diabetes, comorbidities, and the records of cardiovascular (MI, stroke, HF, angina, and composite events) outcomes. Statistical analysis was conducted on SPSS 26.0, and the association of class of drug with the cardiovascular outcomes was assessed using the chi-square test, with a significance level of p < 0.05.

Results: Among the 450 participants, the majority were men (62.7%), with the largest age group (50%) being 40-50 years old. Among those surveyed, 50.2% and 62.2% had hypertension and dyslipidemia, respectively. There were no significant differences among users of metformin and users of sulfonylureas in the total rates of individual cardiovascular outcomes (myocardial infarction (38.4%), stroke (9.1%), heart failure (19.1%), angina (33.1%)). However, metformin users had a lower incidence of total cardiovascular events (5.3%) as compared to sulfonylurea users (4.6%) which was statistically significant (p=0.043). The type of antidiabetic therapy was also strongly associated with the presence of hypertension and dyslipidemia (p < 0.001).

Conclusion: Metformin therapy was correlated with a slightly lower incidence of total cardiovascular events compared to sulfonylurea therapy, validating metformin's first-line status for T2DM. While glycemic control is needed and sulfonylureas provide that, caution is recommended in the presence of significant cardiovascular risk factors. Addressing systemic issues related to hypertension and dyslipidemia along with total adherence to diabetes therapy will achieve the maximum cardiovascular outcomes for patients with diabetes.