Objective: Obesity is a risk factor for chronic kidney disease (CKD) and cardiovascular disease. The association between waist to height ratio (WheiR) and CKD is unclear. This study evaluated the association between WheiR and CKD.
Design and methods: In this longitudinal cohort study, 4841 Japanese workers (3686 males, 1155 females) 18 to 67 years of age in 2008 were followed up until 2011. CKD was defined as an estimated glomerular filtration rate of <60 mL/min/1.73 m² (by the Modification of Diet in Renal Disease equation for Japanese) or dipstick proteinuria (≥1+). Cox proportional hazards models were used to examine the relationship between WheiR and development of CKD.
Results: A total of 384 (7.9%) participants (300 men and 84 women) were found to have new CKD. The incidence of CKD was 13.7, 24.2, 37.9 and 43.7 per 1000 person-years of follow-up in the lowest, second, third and highest quartiles of WheiR, respectively. After adjustment for potential confounders, the adjusted hazard ratios (95% confidence interval) for CKD were 1.00 (reference), 1.23 (0.85, 1.78), 1.59 (1.11, 2.26) and 1.62 (1.13, 2.32) through the quartiles of WheiR, respectively. WheiR had a significant predictive value for the incidence of both proteinuria and low estimated glomerular filtration rate. After subdivision according to gender, the relationship between WheiR and the incidence of CKD was statistically significant in the unadjusted model. However, after adjusting for potential confounders, WheiR was significantly associated with the incidence of CKD in females, whereas it was not significant in males.
Conclusions: WheiR, which is commonly used as an index of central obesity, is associated with CKD. There was a significant gender difference in the relationship between CKD and WheiR.