Nonlinear relationship between triglyceride/high-density lipoprotein cholesterol ratio and chronic kidney disease in US adults: a National Health and Nutrition Examination Survey investigation

Purpose Published data on the association between triglycerides/high-density lipoprotein cholesterol (TG/HDL-C) ratio and chronic kidney disease (CKD) in US populations are limited. We examined the association between TG/HDL-C ratio and the prevalence of CKD using US National Health and Nutrition Examination Survey (NHANES) database. Methods This cross-sectional study included 13,780 US adults from NHANES (1999-2006). CKD was defined as an estimated glomerular filtration rate (eGFR)<60 ml/min/1.73 m(2) or albuminuria. Multivariable logistic regression models were used to examine the relationship between TG/HDL-C ratio and CKD. A generalized additive model (GAM) and smooth curve fitting (penalized spline method) and a two-piecewise logistic regression models were also conducted to address for nonlinearity between TG/HDL-C ratio and CKD. Results The prevalence of CKD was 15.8%. Multiple logistic analyses showed that showed that TG/HDL-C ratio was associated with 5% increased prevalence of CKD. Analyses using restricted cubic spline showed a saturation and nonlinear association between TG/HDL-C ratio and CKD. The inflection point for the curve was found at a TG/HDL-C ratio level of 6.68. The ORs (95% CIs) for CKD were 1.08 (1.04, 1.13) and 0.97 (0.89, 1.05) to the left and right of the inflection point, respectively. None of all stratified variables showed significant effect modification on the association between TG/HDL-C ratio and CKD (P-interaction>0.05). Conclusions Our study suggested saturated effects of TG/HDL-C ratio on the prevalence of CKD among US adults. TG/HDL-C ratio less than 6.68 was positively and independently associated with CKD.