Indices of obesity among type-2 diabetic Hausa-Fulani Nigerians

Background: Obesity has been identified as the most important modifiable risk factor in the aetiology of type-2 diabetes mellitus. In clinical practice, body mass index (BMI) is the commonest index used to define the presence and degree of obesity. Unfortunately, BMI does not define the presence or absence of central obesity which has been shown to be the most pathogenically important in the causation of metabolic disorders including type-2 diabetes. Waist-hip ratio (WHR) has been shown to be a sensitive and reliable index of intra-abdominal obesity as well as intra-abdominal to subcutaneous fat ratio. Study Objective: To define obesity rates using BMI and WHR among type-2 diabetic northern Nigerians. Subjects and Methods: Forty type-2 diabetic subjects and 36 healthy controls were studied. Results: Mean BMI among type-2 diabetic patients was 24.93+ 4.43 Kg M versus 22.93 ± 4.02 Kg M (p<0.02). Overweight occurred in 14(35%) of diabetic subjects versus 8 (22.0) of control subjects. Obesity on the other hand was observed in two (5.0%) of diabetic patients and none among control subjects. Type 2 diabetic patients had significantly much higher WHR compared to control subjects (1.03 ± 0.08 versus 0.92 ± 0.08 respectively, p<0.001). Central obesity was recorded in 38 (95%) type 2 diabetic patients compared to (%) of control subjects. Conclusion: Current cut-off points using BMI may suggest that obesity is not common among type-2 diabetic Northern Nigerians although central obesity is quite common. There may be a need to revisit the cut off points to define obesity in this population.