A cohort of 397 patients who were referred to a vascular lab had PAD diagnosed by noninvasive testing. Fifty-eight percent also had coronary or cerebrovascular disease at baseline. Predictors of total, CVD, and non-CVD mortality were assessed with Cox proportional hazards models, and the incremental value of predictors was evaluated with both the C-statistic and the integrated discrimination improvement (IDI) index.
Total mortality was 11 % at 2-year follow-up and 65 % at an average of 6.6-year of follow-up (maximum, 11.4 years). At 2 years, hs-CRP was a strong and significant predictor of mortality, with a hazard ratio (HR) of 1.56 per standard deviation (P = .006). However, at full follow up, standard CVD risk markers were significant (age, gender, ankle-brachial index, other CVD, and hypertension), but hs-CRP no longer showed a significant relationship (HR 1.12; P = .11). None of the other biomarkers studied showed a significant independent association with mortality. Hs-CRP improved the C-statistic and the IDI beyond standard risk markers at 2 years, but not at full follow-up.
hs-CRP was a strong predictor of short-term mortality in this cohort of PAD patients, while standard risk markers were better at predicting longer-term mortality.