Presence of abdominal aortic calcification is significantly associated with all-cause and cardiovascular mortality in maintenance hemodialysis patients

Abstract

Background: Although abdominal aortic calcification (AAC) is reported as a predictor for cardiovascular mortality in the general population, it is unknown whether this is also true in hemodialysis patients in whom vascular calcification and cardiovascular diseases are highly prevalent.

Study design: Cohort study.

Settings & participants: 515 patients on maintenance hemodialysis therapy at a single center.

Predictor: AAC evaluated in a plain roentgenograph of the lateral abdomen at baseline.

Outcomes & measurements: All-cause and cardiovascular death.

Results: Mean age was 60 +/- 12 (SD) years. AAC was present in 291 patients (56.5%). During a mean follow-up period of 51 +/- 17 months, there were 103 all-cause deaths, of which 41 were from cardiovascular diseases. Of patients with and without AAC, 27.8% and 9.8% died, respectively (11.6% and 3.1% of cardiovascular diseases, respectively). Kaplan-Meier analysis showed that all-cause mortality was significantly greater in patients with AAC compared to those without (P < 0.0001, log-rank test). Similarly, cardiovascular mortality was significantly greater in the former than in the latter group (P = 0.0001, log-rank test). Multivariate Cox proportional hazards analysis found that the presence of AAC was significantly associated with increased all-cause mortality (hazard ratio, 2.07; 95% confidence interval, 1.21 to 3.56; P < 0.01) and increased cardiovascular mortality (hazard ratio, 2.39; 95% confidence interval, 1.01 to 5.66; P < 0.05) after adjustment for age, hemodialysis duration, presence of diabetes, serum albumin level, and C-reactive protein level.

Limitations: Nonquantitative assessment of AAC and the lack of information for medication and history of cardiovascular diseases.

Conclusion: The presence of AAC is significantly associated with both all-cause and cardiovascular mortality in hemodialysis patients, suggesting that careful attention should be given to the presence of AAC in a simple radiograph of the lateral abdomen as a prognostic indicator.