Modeling the impact of obesity on the lifetime risk of chronic kidney disease in the United States using updated estimates of GFR progression from the CRIC study

Abstract

Rationale & objective As the prevalence of obesity continues to rise in the United States, it is important to understand its impact on the lifetime risk of chronic kidney disease (CKD). Study design The CKD Health Policy Model was used to simulate the lifetime risk of CKD for those with and without obesity at baseline. Model structure was updated for glomerular filtration rate (GFR) decline to incorporate new longitudinal data from the Chronic Renal Insufficiency Cohort (CRIC) study. Setting and population The updated model was populated with a nationally representative cohort from National Health and Nutrition Examination Survey (NHANES). Outcomes Lifetime risk of CKD, highest stage and any stage. Model, perspective, & timeframe Simulation model following up individuals from current age through death or age 90 years. Results Lifetime risk of any CKD stage was 32.5% (95% CI 28.6%-36.3%) for persons with normal weight, 37.6% (95% CI 33.5%-41.7%) for persons who were overweight, and 41.0% (95% CI 36.7%-45.3%) for persons with obesity at baseline. The difference between persons with normal weight and persons with obesity at baseline was statistically significant (p<0.01). Lifetime risk of CKD stages 4 and 5 was higher for persons with obesity at baseline (Stage 4: 2.1%, 95% CI 0.9%-3.3%; stage 5: 0.6%, 95% CI 0.0%-1.1%), but the differences were not statistically significant (stage 4: p = 0.08; stage 5: p = 0.23). Limitations Due to limited data, our simulation model estimates are based on assumptions about the causal pathways from obesity to CKD, diabetes, and hypertension. Conclusions The results of this study indicate that obesity may have a large impact on the lifetime risk of CKD. This is important information for policymakers seeking to set priorities and targets for CKD prevention and treatment.