Overweight, obesity and intentional weight loss in chronic kidney disease: NHANES 1999-2006

OBJECTIVE: Obesity and chronic kidney disease (CKD) have emerged as major public health problems. We aimed to examine: a) lifestyle and behavioral factors, b) factors related to pursuing weight loss, and c) weight loss modalities pursued by CKD and non-CKD individuals who are overweight and obese. METHODS: Cross-sectional analysis of 10,971 overweight and obese adult participants in the National Health and Nutrition Examination Surveys conducted between 1999-2006. We examined the differences in lifestyle and behavioral factors between CKD and non-CKD participants and factors associated with pursuing weight loss using survey regression models. RESULTS: The total daily energy intake of the CKD population was lower than the non-CKD group (1987 kcal/day vs. 2063 kcal/day, p=0.02) even after adjusting for relevant covariates. However, the percentage of energy derived from protein was similar between the groups. Sixty-six percent of the CKD population did not meet the minimum recommended leisure time physical activity goals compared to 57% among non-CKD (p<0.001). Fifty percent of CKD participants pursued weight loss (vs. 55% of non-CKD individuals, p=0.01), but the presence of CKD was not independently associated with the pursuit of weight loss in the multivariate model. Among participants pursuing weight loss, modalities including dietary interventions utilized by CKD and non-CKD participants were similar. Eight percent of CKD participants used medications to promote weight loss. CONCLUSIONS: Among the overweight and obese population, lifestyle and behavioral factors related to obesity and weight loss are similar between CKD and non-CKD participants. Insufficient data exist on the beneficial effects of intentional weight loss in CKD and these data show that a significant proportion of the CKD population use diets that may have high protein content and medications to promote weight loss that may be harmful. Future clinical trials evaluating the efficacy and optimal modalities to treat obesity in the CKD population are warranted.