Key result
A 5-kg weight gain was associated with a 1.10 mL/min/1.73 m2 increase in unindexed measured glomerular filtration rate (95% CI 0.87-1.33; P<0.001), but not with BSA-indexed mGFR or eGFR.
Why the study?
Does weight change affect glomerular filtration rate depending on the method of assessment in patients with kidney disease and hypertension?
Cohort (n=1,094)
Does weight change affect glomerular filtration rate depending on the method of assessment in patients with kidney disease and hypertension?
Mean Difference: 1.1 (95% CI 0.87–1.33)
p-value: p=< 0.001
The association between weight change and kidney function varies significantly depending on whether GFR is indexed to body surface area, highlighting the need for robust filtration markers in weight loss trials.
BSA indexing may mask weight-related GFR shifts; hypothesis-generating for unindexed mGFR in weight loss trials.
BACKGROUND: Little is known about the effect of weight loss/gain on kidney function. Analyses are complicated by uncertainty about optimal body surface indexing strategies for measured glomerular filtration rate (mGFR). METHODS: Using data from the African-American Study of Kidney Disease and Hypertension (AASK), we determined the association of change in weight with three different estimates of change in kidney function: (i) unindexed mGFR estimated by renal clearance of iodine-125-iothalamate, (ii) mGFR indexed to concurrently measured BSA and (iii) GFR estimated from serum creatinine (eGFR). All models were adjusted for baseline weight, time, randomization group and time-varying diuretic use. We also examined whether these relationships were consistent across a number of subgroups, including tertiles of baseline 24-h urine sodium excretion. RESULTS: In 1094 participants followed over an average of 3.6 years, a 5-kg weight gain was associated with a 1.10 mL/min/1.73 m(2) (95% CI: 0.87 to 1.33; P < 0.001) increase in unindexed mGFR. There was no association between weight change and mGFR indexed for concurrent BSA (per 5 kg weight gain, 0.21; 95% CI: -0.02 to 0.44; P = 0.1) or between weight change and eGFR (-0.09; 95% CI: -0.32 to 0.14; P = 0.4). The effect of weight change on unindexed mGFR was less pronounced in individuals with higher baseline sodium excretion (P = 0.08 for interaction). CONCLUSION: The association between weight change and kidney function varies depending on the method of assessment. Future clinical trials should examine the effect of intentional weight change on measured GFR or filtration markers robust to changes in muscle mass.
No takes yet. Share an insight, caveat, or question.
Chang et al. (2015) conducted a cohort in Kidney disease and hypertension (n=1,094). Weight change (5-kg weight gain) was evaluated on Change in unindexed measured glomerular filtration rate (mGFR) (MD 1.10, 95% CI 0.87 to 1.33, p=< 0.001). A 5-kg weight gain was associated with a 1.10 mL/min/1.73 m2 increase in unindexed measured glomerular filtration rate (95% CI 0.87-1.33; P<0.001), but not with BSA-indexed mGFR or eGFR.
Synapse has enriched 5 closely related papers on similar clinical questions. Consider them for comparative context: