Among individuals who have normal or reduced levels of glomerular filtration rate (GFR), elevated body mass index (BMI), waist circumference, and waist-to-height ration are independent factors for GFR decline and mortality. This according to a meta-analysis of 39 general population cohorts (n=5,459,014), of which 21 (n=594,496) had data on waist circumference; 6 cohorts with high cardiovascular (CV) risk (n=84,417); and 18 cohorts with chronic kidney disease (CKD) (n=91,607). The included cohorts were from 40 countries with data collected between 1970 and 2017. The primary outcomes were GFR decline and all-cause mortality. Researchers found:

• Over a median follow-up of 8 years, 246,607 (5.6%) individuals in the general population cohorts had GFR decline, and 782,329 (14.7%) died.
• BMI >25 was associated with increased risk of GFR decline during follow-up.
• In the general population, body mass indices of 30, 35, and 40 were associated with 18%, 69%, and 102% increased risk of GFR decline, respectively, compared with BMI of 25.
• The association between elevated BMI and GFR decline risk was qualitatively similar in subgroups by age, sex, race, level of GFR, hypertension, and diabetes status.