Cardiovascular and mortality risk prediction and stratification using urinary albumin excretion in older adults ages 68-102: the Cardiovascular Health Study.
BACKGROUND
Elevated urinary albumin excretion (UAE) is associated with the risk of cardiovascular disease (CVD) and all-cause mortality. We tested the hypothesis that elevated UAE improves cardiovascular risk stratification in an elderly cohort aged 68-102 years.


METHODS
We evaluated UAE in 3112 participants of the Cardiovascular Health Study who attended the 1996-1997 examination and had median follow up of 5.4 years. Elevated UAE was defined as urinary albumin to creatinine ratio > or =30 microg/mg. Microalbuminuria and macroalbuminuria were defined as urinary albumin to creatinine ratio 30-300 microg/mg and >300 microg/mg, respectively. Outcomes included CVD (myocardial infarction, stroke, cardiovascular death) and all-cause mortality. Cox proportional hazards models were used to assess the risk of outcomes associated with elevated UAE.


RESULTS
The prevalence of elevated UAE was 14.3%, 17.1% and 26.9% in those aged 68-74, 75-84 and 85-102 years, respectively. CVD incidence and all-cause mortality were doubled (7.2% and 8.1% per year) in those with microalbuminuria and tripled (11.1% and 12.3% per year) in those with macroalbuminuria compared to those with normal UAE (3.3% and 3.8% per year). The increased CVD and mortality risks were observed in all age groups after adjustment for conventional risk factors. The adjusted population attributable risk percent of CVD and all-cause mortality for elevated UAE was 11% and 12%, respectively. When participants were cross-classified by UAE and Framingham Risk Score categories, the 5-year cumulative incidence of coronary heart disease among participants with elevated UAE and a 5-year predicted risk of 5-10% was 20%, substantially higher than 6.3% in those with UAE <30m microg/mg.


CONCLUSIONS
Elevated UAE was associated with an increased risk of CVD and all-cause mortality in all age groups from 68 to 102 years. Combining elevated UAE with the Framingham risk scores may improve risk stratification for CVD in the elderly.
Cao
Jie J
JJ
Research Department, St Francis Hospital, Division of Cardiology, Stony Brook University, SUNY, 100 Port Washington Boulevard, Roslyn, NY 11576, United States. Jane.Cao@chsli.org
Biggs
Mary L
ML
Barzilay
Joshua
J
Konen
Joseph
J
Psaty
Bruce M
BM
Kuller
Lewis
L
Bleyer
Anthony J
AJ
Olson
Jean
J
Wexler
Jason
J
Summerson
John
J
Cushman
Mary
M
D000368:Aged; D000369:Aged, 80 and over; D000419:Albuminuria; D015415:Biomarkers / Q000652:urine; D015331:Cohort Studies; D003327:Coronary Disease / Q000175:diagnosis / Q000401:mortality* / Q000652:urine*; D003430:Cross-Sectional Studies; D005260:Female; D006306:Health Surveys; D006801:Humans; D008297:Male; D011237:Predictive Value of Tests; D012306:Risk
D015415:Biomarkers