Serum albumin and kidney function decline in HIV-infected women.
BACKGROUND
Serum albumin concentrations are a strong predictor of mortality and cardiovascular disease in human immunodeficiency virus (HIV)-infected individuals. We studied the longitudinal associations between serum albumin levels and kidney function decline in a population of HIV-infected women.


STUDY DESIGN
Retrospective cohort analysis.


SETTING & PARTICIPANTS
Study participants were recruited from the Women's Interagency HIV Study (WIHS), a large observational study designed to understand risk factors for the progression of HIV infection in women living in urban communities. 908 participants had baseline assessment of kidney function and 2 follow-up measurements over an average of 8 years.


PREDICTOR
The primary predictor was serum albumin concentration.


OUTCOMES
We examined annual change in kidney function. Secondary outcomes included rapid kidney function decline and incident reduced estimated glomerular filtration rate (eGFR).


MEASUREMENTS
Kidney function decline was determined by cystatin C-based (eGFR(cys)) and creatinine-based eGFR (eGFR(cr)) at baseline and follow-up. Each model was adjusted for kidney disease and HIV-related risk factors using linear and relative risk regression.


RESULTS
After multivariate adjustment, each 0.5-g/dL decrement in baseline serum albumin concentration was associated with a 0.56-mL/min faster annual decline in eGFR(cys) (P < 0.001), which was attenuated only slightly to 0.55 mL/min/1.73 m(2) after adjustment for albuminuria. Results were similar whether using eGFR(cys) or eGFR(cr). In adjusted analyses, each 0.5-g/dL lower baseline serum albumin level was associated with a 1.71-fold greater risk of rapid kidney function decline (P < 0.001) and a 1.72-fold greater risk of incident reduced eGFR (P < 0.001).


LIMITATIONS
The cohort is composed of only female participants from urban communities within the United States.


CONCLUSIONS
Lower serum albumin levels were associated strongly with kidney function decline and incident reduced eGFRs in HIV-infected women independent of HIV disease status, body mass index, and albuminuria.