Profile of interdialytic ambulatory blood pressure in a cohort of Chinese patients.

Management of hypertension is one of the fundamental interventions in dialysis patients. However, the profile of interdialytic blood pressure (BP) in Chinese dialysis patients remains elusive. We aim to investigate this issue as well as the effect of antihypertensive medication in this population. We performed 44-h ambulatory BP in 90 patients on maintenance hemodialysis. Patients were classified as 'dipping', 'non-dipping' or 'reverse-dipping' based on night/day ratio (N/D) of systolic BP on nondialysis day. The prevalence of blunted circadian BP pattern was strikingly high (92.2%), with more than half of the patients (55.6%) classified as reverse-dipping. There was a close association between high erythropoietin (EPO) dose used and deteriorated circadian rhythm. Patients in the dipping group also displayed a dipping state for heart rate (HR) compared with the other two groups (N/D of HR: 81.5 ± 6.6 vs 92.1 ± 6.0 and 91.3 ± 10.7, P=0.02). Only 26.7% patients had a controlled nocturnal BP. Patients with bedtime dosing had lower N/D of systolic BP compared with patients without (100.1 ± 7.0 vs 105.2 ± 7.1, P=0.01). Non-dipping and reverse-dipping are highly prevalent in Chinese patients. EPO use and autonomic dysfunction may contribute to the blunted circadian rhythm. More tightly control of nighttime BP is an urgent need and bedtime dosing may be beneficial.