Cardiovascular Mortality and Its Risk Factors in Patients on Twice-Weekly Maintenance Hemodialysis: An 18-Month Retrospective Cohort Study from a Tertiary Center in Indonesia.

BACKGROUND

Patients on maintenance hemodialysis (MHD) face cardiovascular mortality far exceeding that of the general population, yet the evidence on risk factors comes overwhelmingly from thrice-weekly cohorts. In Indonesia and many low- and middle-income countries, twice-weekly hemodialysis is the standard regimen funded by national insurance, and the risk factor profile of this underdialysed population has received little attention.

OBJECTIVE

To identify independent risk factors for cardiovascular mortality among Indonesian adults receiving twice-weekly MHD.

METHODS

We analysed the complete eligible population of 162 adults receiving twice-weekly MHD (8-10 hours/week) at a tertiary center in Bandung, followed for 18 months (May 2018-November 2019). Baseline variables were drawn from the unit's REDCap database. Severe hypoalbuminemia was defined as serum albumin ≤3.0 g/dL. Seven variables with bivariate p<0.25 entered modified Poisson regression with robust standard errors to estimate adjusted relative risks (aRR); dialysis vintage was entered in addition on clinical grounds. Model stability was assessed across progressively more parsimonious specifications.

RESULTS

Mean age was 49.7 ± 14.2 years, 47% were men, and cardiovascular events accounted for 92.1% of the 38 deaths. Eighteen-month cardiovascular mortality was 21.6% (35/162); 1-year survival was 80.7%. Six factors were independently associated with cardiovascular death: age >60 years (aRR 3.15, 95% CI 1.65-6.02), Kt/V <1.8 (aRR 2.52, 95% CI 1.35-4.69), diabetic kidney disease (aRR 2.05, 95% CI 1.16-3.63), hyperphosphatemia (aRR 1.94, 95% CI 1.12-3.35), abnormal serum potassium (aRR 1.91, 95% CI 1.09-3.34), and dialysis vintage >60 months (aRR 1.69, 95% CI 1.01-2.81). Age and Kt/V remained significant across all model specifications. Serum albumin discriminated poorly (AUC 0.587); the ≤3.0 g/dL cutoff is reported as exploratory.

CONCLUSION

Older age, inadequate dialysis dose, diabetic etiology, hyperphosphatemia, dyskalemia, and prolonged vintage were independently associated with cardiovascular mortality, with age and dialysis dose the most robust. The findings argue for closer attention to dialysis adequacy and mineral metabolism in reduced-frequency programs.