Background: Hypertension is a major cardiovascular risk factor in hemodialysis patients. This study identified the optimal blood pressure (BP) target for Korean hemodialysis patients using the Korean Renal Dialysis System (KORDS) dataset from the Korean Society of Nephrology and a pooled analysis for previous studies.
Methods: Hemodialysis patients were classified according to their systolic (SBP) and diastolic BP (DBP) at intervals of 20 and 10 mmHg, respectively. As a primary and secondary outcome, all-cause mortality and cardiovascular mortality were evaluated. Subsequently, pooled analysis with previous literatures was performed.
Results: Among 70,607 patients, 13,708 (19.4%) died in 2,426 days (interquartile range, 1,256-4,075 days). Mean SBP and DBP were 143.0 ± 19.6 and 78.5 ± 12.0 mmHg. In multivariable Cox regression, the patients with SBP of <120 and ≥180 mmHg showed 1.10- and 1.12-times increased risk of all-cause mortality compared to SBP of 120-140 mmHg. Meanwhile, DBP showed no significant association. In subgroup analysis, patients aged <70 years and without diabetes had a U-shaped SBP-mortality association. Cardiovascular mortality was increased in SBP of ≥160 mmHg compared to 120-140 mmHg, but it was not in <120 mmHg. Pooled analysis with previous studies mostly showed elevated risk in SBP of <120 mmHg, but the risks in 140-160 and 160-180 mmHg were not consistent.
Conclusion: Extremely lowering BP (<120 mmHg) or uncontrolled hypertension (≥160 mmHg) should be avoided to optimize survival in Korean hemodialysis patients. Detailed analysis for patients with SBP of 120-160 mmHg should be studied further under uniform BP measurement, along with consideration of risk of intradialytic hypotension. Tailored recommendations regarding patient risk factors also should be considered.
Keywords: Blood pressure; Cardiovascular mortality; Hemodialysis; Hypertension; Mortality.