Not all obese subjects of multiethnic origin are at similar risk for developing hypertension and type 2 diabetes

Abstract 

Backgrounds

Whether insulin resistance and not obesity per se is the major contributor to clinical outcomes associated with obesity has not been fully established. This study evaluated in a group of obese Brazilians of multiethnic origin to what extent the prevalence of hypertension and other cardiometabolic risk factors varies as a function of the degree of insulin sensitivity.

Methods

The study involved 118 individuals (mean age of 44±12 years; BMI=38.6±7.9 kg/m²) without evidence of diabetes or cardiovascular disease. Insulin resistance was assessed by HOMA-IR index, which was used to stratify patients into tertiles.

Results

The mean HOMA-IR in tertile 1, the most insulin-sensitive group, was 2.7±0.8 and in tertile 3, the most insulin-resistant group, 9.1±2.4 (P<0.001). Mean arterial pressure showed a linear and significant variation across the HOMA-IR tertiles 1, 2, and 3 (94.3±11.7; 98.7±11.4; 105.0±12.4 mm Hg), as did fasting plasma glucose (93.6±12.1; 98.1±12.7; 100.0±11.0 mg/dL), uric acid (4.7±1.4; 5.9±1.9; 6.3±1.4 mg/dL), HDL-cholesterol (48.1±11.6; 46.5±10.5; 42.2±8.0 mg/dL), and plasma adiponectin (7.8±3.3; 7.0±2.8; 6.3±6.5 µg/mL), respectively. The results indicated that 27.5% of our patients had dysglicemia, 28.2% had hypertriglyceridemia, and 30.7% had arterial hypertension in the most insulin-sensitive tertile, when compared with 51%, 53.8% and 79.4%, respectively, in the most insulin-resistant tertile. A stepwise regression analysis showed that only HOMA-IR and age independently affected the risk for increased systolic blood pressure.

Conclusion

In conclusion, our findings have shown that the risk of developing essential hypertension, type 2 diabetes, and cardiovascular disease is accentuated in obese individuals who are also more insulin resistant.

Keywords: Insulin-resistance, Multiethnic obese, Hypertension, Type 2 diabetes