Body mass index, sedentary lifestyle, and HbA1c predict cardiac autonomic neuropathy in type 2 diabetes

Background Cardiac autonomic neuropathy (CAN) is a serious but often underdiagnosed complication among type 2 diabetes mellitus (T2DM) patients that increases the risk of morbidity and mortality. Evidence on the burden of CAN and its associated factors in Zanzibar is very limited. Therefore, this study aimed to determine the prevalence and predictors of CAN in patients with T2DM attending a tertiary diabetes clinic in Zanzibar. Methods This was a hospital-based cross-sectional study among patients with T2DM attending Mnazi Mmoja Hospital, Zanzibar. All participants were selected by systematic random sampling. CAN was measured using the CAN 504 analyzer with Ewing’s cardiovascular reflex tests. Sociodemographic, clinical, anthropometric, and biochemical data were collected using standardized procedures. A modified Poisson regression model with robust variance was used to identify factors associated with CAN. Results A total of 364 patients were analyzed, with a mean (SD) age of 56 (10.9) years, and the majority were female (n = 243, 66.8%). The prevalence of CAN was found in 291 (79.9%) patients. Of those with CAN, 220 (60.4%) had early CAN, 65 (17.9%) had definite CAN, and only 6 (1.6%) had severe CAN. Patients with normal body mass index (BMI) had lower risk of CAN (aPR 0.86, 95% CI 0.76–0.99, p = 0.036), while patients with sedentary lifestyle (aPR 1.00, 95% CI 1.00–1.00, p = 0.002) and elevated HbA1c levels (aPR 1.01, 95% CI 1.00–1.03, p = 0.013) had higher risk. Conclusion This study revealed a high prevalence of CAN among adults with T2DM attending a tertiary diabetes clinic in Zanzibar. Normal BMI was associated with lower CAN prevalence, whereas greater sedentary behavior and higher HbA1c were associated with higher prevalence. These findings support earlier screening and targeted risk factor modification in high-risk patients.