Association between body mass index and chronic kidney disease in men and women: population-based study of Malay adults in Singapore.

BACKGROUND In contrast to previous studies from western populations, studies from Japan reported a positive association between body mass index (BMI) and chronic kidney disease (CKD) among men but not women. In this context, we examined the relationship between BMI and CKD, by gender, in a study of Malay adults from Singapore. METHODS This was a population-based cross-sectional sample of adults (n = 2783, 53% women, aged 49-80 years), free of clinical cardiovascular disease. The outcome of interest was presence of CKD [estimated glomerular filtration rate (eGFR) <60 mL/min per 1.73 m(2) (n = 517)]. The statistical methods used were logistic and nonparametric logistic regressions. RESULTS Higher BMI levels were found to be positively associated with CKD among Malay men. Among men, compared to BMI quartile 1 (<23 kg/m(2)), the multivariable odds ratio (OR) [95% confidence intervals (CI)] of CKD was 3.12 (1.97-4.94) in quartile 2 (23-24.9 kg/m(2)), 2.49 (1.63-3.79) in quartile 3 (25-29.9 kg/m(2)) and 3.70 (2.13-6.42) in quartile 4 (>or=30 kg/m(2)); P-trend < 0.0001. In contrast, among women BMI levels were not associated with CKD; P-trend = 0.32. In nonparametric models, among men, the observed positive association between BMI and CKD appeared to be present across the full range of BMI values, without any threshold. In contrast, among women, results from nonparametric models were consistent with the conclusion of a lack of association between BMI and CKD. CONCLUSIONS Higher BMI levels were positively associated with CKD among men but not women in a population-based study from Singapore. These results are consistent with the hypothesis of a male gender-specific association between BMI and CKD among Asians.