Comparison of comorbidities, medication use, and clinical outcomes among type 2 diabetes patients in Iran from 2021 to 2023

This repeated cross-sectional study compares comorbidities, medication use, clinical outcomes, and medication costs among patients with type 2 diabetes (T2D) at Qaem Clinic in Qazvin, Iran, across three annual cohorts (2021–2023), with gender-stratified analysis. We conducted a retrospective, repeated cross-sectional analysis of electronic health records (EHR) for all adult patients with confirmed T2D who attended the clinic at least once during the study period (census sampling). Data included demographics, clinical diagnoses (using ICD-10 codes), medication prescriptions, HbA1c levels, and annual medication costs. Statistical analysis employed Chi-square tests for trend and linear regression with year as the independent variable. Missing data proportions were calculated for all variables. Medication costs were adjusted for inflation using the Central Bank of Iran rates. The T2D patient population grew from 2,391 in 2021 to 2,739 in 2023. Women consistently represented 61–62% of patients. Gender-stratified analysis revealed women had a higher prevalence of hypothyroidism (7.8% vs. 4.1%, p < 0.001) and mental health disorders (4.2% vs. 2.7%, p = 0.012), while men showed higher ischemic heart disease (15.3% vs. 11.8%, p = 0.008). Key findings included: modest increase in hypertension (55.0% to 56.1%, p = 0.038) and hypothyroidism (5.0% to 7.1%, p = 0.005); decrease in heart failure (20.1% to 16.9%, p = 0.008); decline in metformin use (53.7% to 50.0%, p = 0.012) with compensatory increase in sulfonylureas (6.2% to 14.2%, p < 0.001); and slight increase in mean HbA1c (6.7% to 7.0%, p = 0.025). After inflation adjustment, medication costs increased 1.8-fold (from 5.19 to 9.34 billion constant 2021 Rials, p < 0.001). Detailed comorbidity trends and cost data are presented in Tables 4 and 6, respectively. This repeated cross-sectional analysis identifies clinically meaningful differences in T2D care between 2021 and 2023. The shift from metformin to sulfonylureas and worsening glycemic control suggests potential gaps in guideline-based care. We recommend: (1) targeted provider education on ADA/EASD prescribing guidelines, (2) integration of mental health screening into routine diabetes care, (3) investigation of medication affordability barriers, (4) gender-specific management strategies, and (5) establishment of multi-center surveillance systems to monitor diabetes care quality nationally.