FIG. 2.

Serum cystatin C levels predict mortality in the Health, Aging, and Body Composition Study (Health ABC) cohort and are associated with renal failure and atherosclerotic cardiovascular disease. (A) The hazard ratio (HR) associated with high cystatin C (cystatin C≥1.30) was estimated in the full Health ABC cohort and each of 25 subcohorts. Significant HRs are indicated by an asterisk symbol (*). Point estimates with 95% confidence intervals are listed in the right margin. Sample sizes used for each subgroup are listed at the end of each horizontal bar (participants with missing data were excluded from calculations). A 0-1 indicator was used as the independent variable in Cox regression models, where the value of the indicator was 1 for participants with high cystatin C (cystatin C≥1.30) and 0 otherwise. HR estimates are adjusted for study site (Memphis or Pittsburgh). (B) The HR associated with low to high cystatin C intervals (windows) was evaluated. Participants were sorted in ascending order according to measured cystatin C (horizontal axis). A sliding window analysis was then performed in which the HR was estimated for a window of 100 participants relative to all other participants outside of the window. The solid black line represents the estimated HR for a given window of 100 participants, and the dark grey region outlines a 95% confidence interval. The light grey vertical region in the background outlines the middle 50% of cystatin C levels among all participants (i.e., interquartile range). (C) The relative risk of (assigned) underlying causes of death was evaluated in participants with cystatin C≥1.30 (n=261 deaths) and participants with cystatin C<1.30 (n=1,083 deaths). Assigned causes of death are sorted from most frequent to least frequent among those with cystatin C≥1.30 (frequencies are given in parentheses).