Introduction: We investigated the association between intradialytic hypotension (IDH) and coronary artery calcification and their effects on mortality in hemodialysis (HD) patients.
Methods: Consecutive patients undergoing maintenance HD were enrolled. The study timeline included the baseline (day 1), exposure assessment (day 1-day 22), and outcome assessment (day 23-3 years) periods. IDH was defined as a nadir systolic blood pressure (SBP) of <100 mmHg or vasopressor use during at least 2 of 10 HD sessions in the exposure assessment period. The clinical data at baseline and the Agatston coronary artery calcium score (CACS) were assessed in the exposure assessment period.
Findings: The median age and dialysis vintage were 67 years [60-75 years] and 73 months [37-138 months], respectively. IDH occurred in 37 patients (21.4%), and the CACS was higher in the IDH group than in the non-IDH group (p = 0.08). IDH was associated with CACS, diabetes mellitus, mean predialysis SBP, and mean ultrafiltration volume (p < 0.05). The cutoff CACS for mortality was 1829 (sensitivity: 69%, specificity: 77%). In all, 45 all-cause deaths and 19 cardiovascular deaths occurred over 3 years. Patients with both IDH and a CACS of ≥1829 had a lower 3-year cumulative survival from cardiovascular death (66.7%) than those with a CACS of ≥1829 (80.3%), IDH (88.5%), or neither (95.5%) (p < 0.01). IDH, a CACS of ≥1829, and IDH + CACS of ≥1829 were predictors of 3-year all-cause and cardiovascular mortality (p < 0.05). The hazard ratio for cardiovascular mortality was highest in the group with IDH + CACS ≥ 1829.
Discussion: A high CACS may be a biomarker for IDH. Both IDH and CACS were risk factors for all-cause and cardiovascular mortality in patients undergoing HD, and there was a synergistic interaction between IDH and high CACS for cardiovascular mortality.
Keywords: coronary artery calcium score; hemodialysis; intradialytic hypotension; mortality.
© 2022 International Society for Hemodialysis.