Timing of Antihypertensive Medications on Key Outcomes in Hemodialysis

High blood pressure (BP) is a major modifiable risk factor for cardiovascular disease, and upwards of 90% of patients with end- stage renal disease (ESRD) have high BP. Appropriate BP management, therefore, is a fundamental part of patient care in ESRD, yet the question of when best to take antihypertensive medications relative to the hemodialysis treatment session remains unanswered. Many patients on hemodialysis suffer from an abrupt fall in BP during the dialysis session (i.e., intradialytic hypotension [IDH]), a phenomenon that is associated with numerous adverse outcomes. In an attempt to minimize IDH, patients are often told to withhold antihypertensive medications prior to hemodialysis, and current guidelines suggest taking antihypertensive medications at night to minimize IDH. However, there are no data regarding the safety of these antihypertensive medication timing strategies, or whether these strategies are effective in reducing IDH.

Inclusion criteria

• Age ≥ 18 years
• On in-center thrice weekly hemodialysis
• Dialysis start time in the morning
• Taking at least one antihypertensive medication

Exclusion criteria

• Initiation of hemodialysis within previous 90 days
• Inability to provide informed consent
• Currently participating in another clinical trial (intervention study)
• >2 unexcused missed dialysis sessions in the previous 30 days
• Documented heart failure with reduced ejection fraction (left ventricular ejection fraction < 40%)
• Cardiovascular event (e.g. myocardial infarction, stroke, heart failure) or procedure (e.g., coronary artery bypass, peripheral arterial bypass grafting, carotid artery procedures, aortic procedures) or hospitalization for unstable angina within the previous 90 days
• End-stage liver disease
• Planned kidney transplant within the next 90 days
• Planned dialysis modality switch (to home hemodialysis, peritoneal dialysis, nocturnal hemodialysis) within the next 90 days
• Pregnancy, currently trying to become pregnant
• Active infection requiring antibiotic, antifungal or antiviral therapies
• Any factors judged by the treatment team to be likely to limit adherence to the interventions

• Active alcohol or substance abuse within the last 12 months
• Plans to move outside of the treatment area within in the next 90 days
• Other medical, psychiatric, or behavioral factors that in the judgement of the study team may interfere with study participation or the ability to follow the intervention protocol