Body-mass index and risk of advanced chronic kidney disease: Prospective analyses from a primary care cohort of 1.4 million adults in England

Abstract

BackgroundIt is uncertain whether being overweight, but not obese, is associated with advanced chronic kidney disease (CKD) and how the size and shape of associations between body-mass index (BMI) and advanced CKD differs among different types of people.MethodsWe used Clinical Practice Research Datalink records (2000–2014) with linkage to English secondary care and mortality data to identify a prospective cohort with at least one BMI measure. Cox models adjusted for age, sex, smoking and social deprivation and subgroup analyses by diabetes, hypertension and prior cardiovascular disease assessed relationships between BMI and CKD stages 4–5 and end-stage renal disease (ESRD).Findings1,405,016 adults aged 20–79 with mean BMI 27.4kg/m2 (SD 5.6) were followed for 7.5 years. Compared to a BMI of 20 to <25kg/m2, higher BMI was associated with a progressively increased risk of CKD stages 4–5 (hazard ratio 1.34, 95% CI 1.30–1.38 for BMI 25 to <30kg/m2; 1.94, 1.87–2.01 for BMI 30 to <35kg/m2; and 3.10, 2.95–3.25 for BMI ≥35kg/m2). The association between BMI and ESRD was shallower and reversed at low BMI. Current smoking, prior diabetes, hypertension or cardiovascular disease all increased risk of CKD, but the relative strength and shape of BMI-CKD associations, which were generally log-linear above a BMI of 25kg/m2, were similar among those with and without these risk factors. There was direct evidence that being overweight was associated with increased risk of CKD stages 4–5 in these subgroups. Assuming causality, since 2000 an estimated 39% (36–42%) of advanced CKD in women and 26% (22–30%) in men aged 40–79 resulted from being overweight or obese.ConclusionsThis study provides direct evidence that being overweight increases risk of advanced CKD, that being obese substantially increases such risk, and that this remains true for those with and without diabetes, hypertension or cardiovascular disease. Strategies to reduce weight among those who are overweight, as well as those who are obese may reduce CKD risk, with each unit reduction in BMI yielding similar relative reductions in risk.

Adiposity and risk of decline in glomerular filtration rate: meta-analysis of individual participant data in a global consortium

“…Several population based studies have found obesity to be a risk factor for CKD and end stage kidney disease (ESKD), although risk estimates have varied considerably between studies. 5 6 7 8 9 10 The disparate findings could relate to differences in population demographics, study era, length of follow-up, statistical adjustment for comorbid conditions, or the definition of ESKD. In addition, the relation between obesity and risk of death remains uncertain in patients with CKD, 11 12 13 14 15 who face increased risk of malnutrition and muscle wasting, potentially limiting the use of body mass index to estimate risk.…”

Obesity‐associated glomerular inflammation increases albuminuria without renal histological changes

“…Obesity is one of the common causes of chronic kidney disease (CKD), independent of glycemic control . Recent studies suggest that body mass index is associated with the incidence of CKD . We have shown that obesity‐induced abnormal metabolites may play a significant role in increasing vascular endothelial growth factor (VEGF) and subsequently the development of CKD .…”

Metabolic Disease and Chronic Kidney Disease among Women in Indonesia: A Cross-Sectional Population-Based Survey

“…This is in line with previous research, which revealed that obesity substantially raises the risk of CKD and even remains true for those with and without diabetes, hypertension, or cardiovascular disease. So it is suggested to reduce weight among those who are overweight, and those who are obese can reduce the risk of CKD, with each BMI reduction unit resulting in relatively similar risk reduction (21). A high body mass index is one of the strongest risk factors for new-onset CKD.…”