Effectiveness of a Structured Exercise Intervention to Normalize Blood Pressure and Nocturnal Dipping in Hypertensive Patients (End-Ht) in Hong Kong Primary Care: A RCT

Objective: Non-dipping blood pressure (BP) pattern during sleep is an independent predictor of cardiovascular events beyond daytime and nighttime BP levels, yet no standard treatment currently exists. A previous pilot trial suggested that six months of aerobic training could reduce non-dipping by 44%, with 8 out of 18 participants transitioning to dipper status. Building on this, we conducted a largest-to-date randomized controlled trial (RCT) to evaluate whether the Exercise is Medicine (EIM) program could normalize non-dipping compared to usual care. Design and method: The EIM program was designed using behavioral therapy principles to promote long-term exercise habits and included a 12-week structured exercise class, nursing interventions with motivational interviewing, IT support, and ongoing follow-up with feedback. A total of 198 non-dippers were randomized in a 1:1 ratio to either the EIM program or usual care. The primary outcome was the proportion of non-dippers at three months, analyzed using logistic regression under the intention-to-treat principle. Secondary outcomes included non-dipping status at 12 months, ambulatory and office BP measurements at three and 12 months, and exercise levels at three, six, and 12 months. Protocol was published: https://doi.org/10.1093/ajh/hpab019 Results: Among 198 participants, most were female (58.9%) and retired (52.5%), with a mean age of 63.5 years; 90.9% were on antihypertensive medications. At three months, 33.0% of the EIM group and 32.5% of the control group transitioned to dipper status. At 12 months, 41.2% of the EIM group and 28.6% of the control group became dippers. However, no significant differences in dipping status were observed at three months or in secondary outcomes at any time point. Similarly, nighttime, daytime, and 24-hour systolic and diastolic BP showed no significant differences between groups at three or 12 months. Conclusions: In contrast to previous smaller trials, this RCT demonstrated that a structured exercise program did not normalize non-dipping status in primary care patients. Although exercise remains an essential recommendation for all individuals with hypertension, clinicians should explore alternative strategies to address non-dipping BP patterns. Further research to identify effective treatments for non-dipping BP is urgently needed.