Incidence, predictors, and population attributable fraction of hypertension among adults with diabetes mellitus in North Gondar Zone, Ethiopia: a retrospective cohort study

Hypertension is a common and serious complication of diabetes mellitus caused by metabolic and vascular changes that increase peripheral vascular resistance, raising the risk of cardiovascular disease, chronic kidney disease, and premature mortality. However, evidence on its incidence and population burden in Ethiopia is limited. Therefore, this study aimed to identify predictors and estimated the population attributable burden of incident hypertension in North Gondar Zone, Ethiopia. An institution-based retrospective follow-up study was conducted among 820 individuals with diabetes mellitus at public hospitals, in North Gondar Zone. Data from January 2020 to December 2024 were extracted using a structured checklist, and systematic random sampling was applied. Log-binomial regression estimated adjusted risk ratios (ARR) with 95% confidence intervals using STATA V-17. Post-estimation methods, including marginal effects (delta method) and the PUNAF approach, were used to compute AAR, APAF, and APAR. The cumulative incidence of hypertension was 34% (95% CI: 31–38%), with an incidence density of 149 per 1,000 person-years (95% CI: 120–184). Significant predictors included age ≥65 years (ARR = 2.60), rural residence (ARR = 1.31), overweight (ARR = 1.31), elevated LDL (ARR = 1.22), history of hospitalization (ARR = 1.93), and follow-up >1 month (ARR = 1.88), all increasing risk. Conversely, female sex (ARR = 0.71), glycemic control (ARR = 0.59), and medication compliance (ARR = 0.60) were protective factors. At the population level, older age, hospitalization history, and poor follow-up contributed the highest attributable burden, whereas glycemic control and medication adherence showed substantial protective population impact. The incidence of hypertension among individuals with diabetes mellitus high. Older age, rural residence, overweight, elevated low-density lipoprotein, hospitalization history, and infrequent follow-up increased risk, while female sex, glycemic control, and medication adherence were protective. Strengthening World Health Organization–guided diabetes care through screening, metabolic control, adherence, and regular follow-up, especially for high-risk groups, is essential to reduce hypertension burden.