Prevalence and determinants of insulin resistance among middle-aged adults in rural northern Ghana: an Awi-Gen cross-sectional study

Introduction: Insulin resistance (IR) is linked to several metabolic diseases including type 2 diabetes mellitus (T2DM), metabolic syndrome, and metabolic dysfunction-associated fatty liver disease (MAFD). The factors that contribute to IR in rural African populations remain largely unknown. Understanding the determinants of IR will contribute to the management of several non-communicable diseases (NCDs). Methods: A cross-sectional study was conducted in two rural districts in northern Ghana involving male and female participants, aged 40 to 60 years, who were recruited into the study between the years 2015 and 2016. Sociodemographic, lifestyle, anthropometric, ultrasound, blood lipid profile, blood glucose and insulin, urine creatinine and urine protein data were collected. Insulin resistance was determined using the Homeostasis Model Assessment of Insulin Resistance (HOMA-IR) formula. Multivariable linear regression analyses were performed between log-transformed IR and several variables. All association analyses were considered significant at p < 0.05. Results: The median (log-transformed) IR among women (0.54) was significantly higher than that among men (0.43) (p < 0.001). The prevalence of IR was 7.6% in the study population with more women having IR (9.9%) than men (4.5%) (p = 0.007). Drivers of IR among women were unmarried status (β = 1.19, p = 0.037), smoking (β = 8.33, P = 0.001) and triglyceride (TG) (β = 2.09, p = 0.016) while that among men were body mass index (BMI) (β = 0.47, p = 0.013), right carotid intima median thickness (CIMT_right) (β = 5.08, p = 0.033), visceral adipose tissue (VAT) (β = 0.59, p = 0.031) and TG (β = 5.58, p < 0.001). Among the total population, vendor meal consumption (β = 0.41, p = 0.001), CIMT_right (β = 3.54, p = 0.028), low-density lipoprotein cholesterol (LDL-C) (β = 1.08, p = 0.012), and TG (β = 2.87, p < 0.001) were linked to IR. Conclusions: Lifestyle, adiposity, CIMT_right and lipid markers contribute to driving IR levels and that these factors are gender-specific in this northern rural Ghanaian population.