Publications

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.

STUDY DESIGN

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

SETTING & PARTICIPANTS

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

PREDICTOR

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.

OUTCOME

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.

LIMITATIONS

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.

BACKGROUND

The association between a history of cancer and mortality has not been studied in a propensity-matched population of community-dwelling older adults.

METHODS

Of the 5795 participants in the Cardiovascular Health Study, 827 (14%) had self-reported physician-diagnosed cancer at baseline. Propensity scores for cancer were used to assemble a cohort of 789 and 3118 participants with and without cancer respectively who were balanced on 45 baseline characteristics. Cox regression models were used to determine the association between cancer and all-cause mortality among matched patients, and to identify independent predictors of mortality among unmatched cancer patients.

RESULTS

Matched participants had a mean (SD) age of 74 (6) years, 57% were women, 10% were African Americans, and 38% died from all causes during 12 years of follow-up. All-cause mortality occurred in 41% and 37% of matched participants with and without a history of cancer respectively (hazard ratio when cancer was compared with no cancer, 1.16; 95% confidence interval, 1.02-1.31; P=0.019). Among those with cancer, older age, male gender, smoking, lower than college education, fair-to-poor self-reported health, coronary artery disease, diabetes mellitus, chronic kidney disease, left ventricular hypertrophy, increased heart rate, low hemoglobin and low baseline albumin were associated with increased risk of mortality.

CONCLUSIONS

Among community-dwelling older adults, a history of cancer was associated with increased mortality and among those with cancer, several socio-demographic variables and morbidities predicted mortality. These findings suggest that addressing traditional risk factors for cardiovascular mortality may help improve outcomes in older adults with a history of cancer.

OBJECTIVE

Circulating angiogenic cells (CACs), also termed endothelial progenitor cells, play an integral role in vascular repair and are functionally impaired in coronary artery disease (CAD). The role of nitric oxide (NO) in CAC function is poorly understood. We hypothesized that CAC migration toward angiogenic signals is modulated by both NO synthase (NOS) expression and functional response to NO.

METHODS AND RESULTS

Similar to endothelial cells, CAC chemotaxis to vascular endothelial growth factor (VEGF) was blocked by inhibition of NOS, phosphatidylinositol 3-kinase, or guanylyl cyclase or by treatment with an NO scavenger. Addition of an NO donor (S-nitroso-N-acetylpenicillamine) and the NOS substrate l-arginine increased random cell migration (chemokinesis) and enhanced VEGF-dependent chemotaxis. Healthy CACs expressed endothelial NOS, but endothelial NOS was not detected in CAD patient CACs. Both chemokinesis and chemotaxis to VEGF of patient CACs were decreased compared with healthy CACs but were restored to healthy values by S-nitroso-N-acetylpenicillamine. In parallel, CAD patients exhibited lower flow-mediated vasodilation and plasma NO source nitrite than young, healthy subjects, indicating endothelial dysfunction with reduced NO bioavailability.

CONCLUSIONS

NOS activity is required for CAC chemotaxis. In CAD patients, impairment of NOS expression and NO bioavailability, rather than response to NO, may contribute to dysfunction of CACs and limit their regenerative capacity.