Cystatin C, albuminuria, and 5-year all-cause mortality in HIV-infected persons.
BACKGROUND
Compared with controls, human immunodeficiency virus (HIV)-infected persons have a greater prevalence of kidney disease, assessed according to high cystatin C level and albuminuria, but not according to creatinine level. However, the clinical importance of increased cystatin C level and albuminuria in the HIV-infected population has not been studied.


METHODS
We conducted an observational cohort study to determine the association of kidney disease (measured according to albuminuria, cystatin C, and serum creatinine) with mortality.


METHODS
922 HIV-infected persons enrolled in the FRAM (Fat Redistribution and Metabolic Change in HIV Infection) Study.


METHODS
Serum cystatin C and serum creatinine levels were used to estimate glomerular filtration rates (eGFR(SCysC) and eGFR(SCr), respectively). Albuminuria was defined as a positive urine dipstick result (≥ 1+) or urine albumin-creatinine ratio >30 mg/g.


RESULTS
5-Year mortality.


RESULTS
At baseline, decreased kidney function (eGFR(SCysC) <60 mL/min/1.73 m(2)) or albuminuria was present in 28% of participants. After 5 years of follow-up, mortality was 48% in those with both eGFR(SCysC) < 60 mL/min/1.73 m(2) and albuminuria, 23% in those with eGFR(SCysC) < 60 mL/min/1.73 m(2) alone, 20% in those with albuminuria alone, and 9% in those with neither condition. After multivariable adjustment for demographics, cardiovascular risk factors, HIV-related factors, and inflammatory marker levels, eGFR(SCysC) < 60 mL/min/1.73 m(2) and albuminuria were associated with a nearly 2-fold increase in mortality, whereas eGFR(SCr) < 60 mL/min/1.73 m(2) did not appear to have a substantial association with mortality. Together, eGFR(SCysC) <60 mL/min/1.73 m(2) and albuminuria accounted for 17% of the population-level attributable risk of mortality.


CONCLUSIONS
Vital status was unknown in 261 participants from the original cohort.


CONCLUSIONS
Kidney disease marked by albuminuria or increased cystatin C level appears to be an important risk factor for mortality in HIV-infected individuals. A substantial proportion of this risk may be unrecognized because of the current reliance on serum creatinine to estimate kidney function in clinical practice.
Choi
Andy
A
University of California, San Francisco, CA, USA.
Scherzer
Rebecca
R
Bacchetti
Peter
P
Tien
Phyllis C
PC
Saag
Michael S
MS
Gibert
Cynthia L
CL
Szczech
Lynda A
LA
Grunfeld
Carl
C
Shlipak
Michael G
MG
D000328:Adult; D000419:Albuminuria / Q000453:epidemiology / Q000209:etiology* / Q000378:metabolism; D015415:Biomarkers / Q000097:blood; D002423:Cause of Death / Q000639:trends; D055316:Cystatin C / Q000097:blood*; D005260:Female; D005500:Follow-Up Studies; D005919:Glomerular Filtration Rate; D015658:HIV Infections / Q000150:complications / Q000378:metabolism / Q000401:mortality*; D006801:Humans; D015994:Incidence; D008297:Male; D008875:Middle Aged; D009391:Nephelometry and Turbidimetry; D015995:Prevalence; D012189:Retrospective Studies; D014481:United States / Q000453:epidemiology
D015415:Biomarkers; D055316:Cystatin C