The Effect of Antihypertensive Medication Timing on Morbidity and Mortality

NCT ID: NCT02990663

Last Updated: 2024-08-27

Basic Information

• Recruitment Status: COMPLETED
• Clinical Phase: PHASE4
• Total Enrollment: 3357 participants
• Study Classification: INTERVENTIONAL
• Study Start Date: 2017-03-31
• Study Completion Date: 2023-12-22

Brief Summary

High blood pressure is common and its presence increases the risk of cardiovascular mortality and morbidity (most notably stroke, myocardial infarction, and congestive heart failure). Given blood pressure is normally higher during the day than it is overnight, blood pressure lowering medications are traditionally taken in the morning. However a randomized trial of 2156 Spanish hypertension patients published in 2010 ("MAPEC"), suggests a large (61%) reduction in mortality and cardiovascular morbidity if such medications are instead taken at bedtime. This degree of benefit far exceeds other established methods of cardiovascular risk reduction - and such a surprisingly large effect requires independent confirmation for practice to change. BedMed is a pragmatic randomized controlled trial facilitated by over 400 Canadian family physician members of the Pragmatic Trials Collaborative. During the conduct of this trial consenting hypertensive primary care patients, already established on one or more antihypertensive medications, will be randomized to either morning or bedtime antihypertensive use. Patient oriented trial outcomes evaluating both potential benefits and harms will be drawn largely from administrative health data that is routinely collected on all residents of Canada's publicly funded health care system. This trial is being conducted in 5 Canadian provinces and will continue to collect data until late 2023, at which point more than 255 primary outcome events are anticipated.

Detailed Description

THE OPPORTUNITY BEDTIME PRESCRIBING MIGHT PROVIDE: Blood pressure normally exhibits a circadian rhythm with relatively lower pressures during sleep.(Ref 1) Lack of this sleep time "dip" correlates strongly with adverse cardiovascular events and BP correlates most strongly with such events when measured at night (i.e. during sleep).(Ref 2-5) Motivated by such observations, Spanish researchers studied the effect of taking BP medication at BEDTIME (when the effect on nighttime BP would be greatest) versus conventional morning use, when most BP medications are taken. The results of this study (the MAPEC trial) were striking.(Ref 6) Over a median 5.6 years follow-up, adverse cardiovascular events occurred in 187 of 1084 subjects taking BP medication in the morning but only 68 of 1072 subjects who took their BP medication at bedtime (relative risk 0.39, 95%CI [0.29-0.51], p < 0.001). This 61% reduction in adverse events was similar for all individual components of the primary outcome (including death from all causes, stroke, MI, new angina pectoris, CHF and retinal artery occlusions). If true, a switch to bedtime prescribing would have more impact on the health of hypertensive patients than whether high BP is treated at all. However extraordinary claims require extraordinary evidence - independent replication of such surprising findings is needed for widespread practice change to occur.

BEDMED: The BedMed trial is a pragmatic primary care trial intended to verify whether bedtime antihypertensive use, as compared to conventional morning use, reduces major adverse cardiovascular events. It is designed as an adaptive randomized registry trial within community primary care and draws both trial outcomes and baseline covariates from provincial administrative claims data (vital statistics, hospital separations, physician services, prescription dispenses, laboratory data). BedMed is government funded/facilitated, and has over 400 volunteer primary care providers recruiting participants in 5 Canadian provinces (Alberta, British Columbia, Saskatchewan, Manitoba, and Ontario). It was originally intended that the trial would continue until 406 primary outcome events were observed, however funding will expire before this occurs. As a result, BedMed will continue to recruit participants until early 2022 and complete data collection in late 2023, at which time more than 255 primary outcome events are anticipated (based on blinded observation of total events gathered at the end of 2021). The trial relies heavily on a collaboration between the volunteer family physicians of the Pragmatic Trials Collaborative (www.PragmaticTrials.ca) who will recruit for the trial and the Alberta SPOR Support Unit's Data Platform - which will facilitate accessing and analyzing the relevant administrative databases from multiple provinces (http://www.aihealthsolutions.ca/initiatives-partnerships/spor/).

DIURETIC SUB-STUDY: The "adaptive" element of the BedMed trial design refers to an interim examination of bedtime diuretic tolerance. Although it is commonly believed that diuretics can't be taken at bedtime without inducing unwanted nocturia, the sparse evidence in the literature suggests this may not be the case.(Ref 7,8) Rather than excluding patients whose only medication is a diuretic the investigators will instead initially include such patients and evaluate bedtime diuretic tolerance early on in the trial to determine whether or not such patients should continue to be enrolled. Specifically, upon allocating to bedtime dosing 203 patients whose only BP medication is an AM diuretic, the investigators will analyze 6-week compliance to bedtime allocation for all participants with a single morning BP medication (of all types). If diuretic compliance is worse, the "adaptive" trial design will exclude enrolment of additional patients whose only BP medication is a diuretic. The BedMed investigators will report on bedtime diuretic tolerance separate from (and in advance of) the main BedMed analysis.

INTERIM SAFETY ANALYSIS: An independent data safety monitoring board (DSMB) organized and chaired by Jim Wright (Cochrane Hypertension Review Group Coordinating Editor) is expected to review all data in March 2022, at which time approximately 150-160 primary outcome events are expected. If p is ≤ 0.001 for benefit (the Haybittle-Peto boundary - recommended to reduce the chance of stopping too early and magnifying benefit), or if p is ≤ 0.05 for harm, the DSMB will apply clinical judgement and make recommendations to the steering committee on whether the trial should stop early.

Conditions

Hypertension

Study Design

• Allocation Method: RANDOMIZED
• Intervention Model: PARALLEL
• Primary Study Purpose: TREATMENT
• Blinding Strategy: SINGLE

Study Groups

Bedtime BP Meds

Use of blood pressure lowering medication at bedtime

Group Type: EXPERIMENTAL

Use of blood pressure lowering medication at bedtime

Intervention Type: OTHER

Blood pressure lowering medications will be switched (one at a time as tolerated) to bedtime, or maintained at bedtime if already taken at that time. All decisions related to which, and how many, medications to switch are at the discretion of the care provider.

Morning BP Meds

Use of blood pressure lowering medication in the morning

Group Type: ACTIVE_COMPARATOR

Use of blood pressure lowering medication in the morning

Intervention Type: OTHER

Blood pressure lowering medications will be switched (one at a time as tolerated) to morning, or maintained in the morning if already taken at that time. All decisions related to which, and how many, medications to switch are at the discretion of the care provider.

Interventions

Use of blood pressure lowering medication at bedtime

Blood pressure lowering medications will be switched (one at a time as tolerated) to bedtime, or maintained at bedtime if already taken at that time. All decisions related to which, and how many, medications to switch are at the discretion of the care provider.

Intervention Type: OTHER

Use of blood pressure lowering medication in the morning

Blood pressure lowering medications will be switched (one at a time as tolerated) to morning, or maintained in the morning if already taken at that time. All decisions related to which, and how many, medications to switch are at the discretion of the care provider.

Intervention Type: OTHER

Eligibility Criteria

Inclusion Criteria

1. Hypertension diagnosis as assigned by a physician or nurse practitioner

2. ≥ 1 blood pressure medication taken once daily, or primary care provider willing to convert ≥ 1 blood pressure medication to once daily

3. Community dwelling (i.e. not residing in a nursing home; assisted living permitted)

Exclusion Criteria

1. Palliative (as per primary care provider's judgement)

2. Unable to provide informed consent (as per primary care provider's judgement)

3. Personal history of glaucoma or use of glaucoma medications

4. Sleep disrupting shift work (more than 3 shifts/month during participant's regular sleeping hours)

• Minimum Eligible Age: 19 Years
• Eligible Sex: ALL
• Accepts Healthy Volunteers: No

Sponsors

Alberta Innovates Health Solutions

OTHER

Sponsor Role: collaborator

Alberta Health services

OTHER

Sponsor Role: collaborator

Canadian Institutes of Health Research (CIHR)

OTHER_GOV

Sponsor Role: collaborator

University of Alberta

OTHER

Sponsor Role: lead

Responsible Party

Responsibility Role: SPONSOR

Principal Investigators

Scott R Garrison, MD, PhD

Role: PRINCIPAL_INVESTIGATOR

University of Alberta

Locations

University of Alberta

Edmonton, Alberta, Canada

University of British Columbia

Vancouver, British Columbia, Canada

University of Manitoba

Winnipeg, Manitoba, Canada

University of Toronto

Toronto, Ontario, Canada

University of Saskatchewan

Saskatoon, Saskatchewan, Canada

Countries

Canada

References

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Reference Type: BACKGROUND

PMID: 7607733 (View on PubMed)

Clement DL, De Buyzere ML, De Bacquer DA, de Leeuw PW, Duprez DA, Fagard RH, Gheeraert PJ, Missault LH, Braun JJ, Six RO, Van Der Niepen P, O'Brien E; Office versus Ambulatory Pressure Study Investigators. Prognostic value of ambulatory blood-pressure recordings in patients with treated hypertension. N Engl J Med. 2003 Jun 12;348(24):2407-15. doi: 10.1056/NEJMoa022273.

Reference Type: BACKGROUND

PMID: 12802026 (View on PubMed)

Verdecchia P, Porcellati C, Schillaci G, Borgioni C, Ciucci A, Battistelli M, Guerrieri M, Gatteschi C, Zampi I, Santucci A, Santucci C, Reboldi G, et al. Ambulatory blood pressure. An independent predictor of prognosis in essential hypertension. Hypertension. 1994 Dec;24(6):793-801. doi: 10.1161/01.hyp.24.6.793.

Reference Type: BACKGROUND

PMID: 7995639 (View on PubMed)

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Reference Type: BACKGROUND

PMID: 17389258 (View on PubMed)

Fagard RH, Celis H, Thijs L, Staessen JA, Clement DL, De Buyzere ML, De Bacquer DA. Daytime and nighttime blood pressure as predictors of death and cause-specific cardiovascular events in hypertension. Hypertension. 2008 Jan;51(1):55-61. doi: 10.1161/HYPERTENSIONAHA.107.100727. Epub 2007 Nov 26.

Reference Type: BACKGROUND

PMID: 18039980 (View on PubMed)

Hermida RC, Ayala DE, Mojon A, Fernandez JR. Influence of circadian time of hypertension treatment on cardiovascular risk: results of the MAPEC study. Chronobiol Int. 2010 Sep;27(8):1629-51. doi: 10.3109/07420528.2010.510230.

Reference Type: BACKGROUND

PMID: 20854139 (View on PubMed)

Rembratt A, Norgaard JP, Andersson KE. Nocturia and associated morbidity in a community-dwelling elderly population. BJU Int. 2003 Nov;92(7):726-30. doi: 10.1046/j.1464-410x.2003.04467.x.

Reference Type: BACKGROUND

PMID: 14616455 (View on PubMed)

Asplund R. Nocturia in relation to sleep, health, and medical treatment in the elderly. BJU Int. 2005 Sep;96 Suppl 1:15-21. doi: 10.1111/j.1464-410X.2005.05653.x.

Reference Type: BACKGROUND

PMID: 16083452 (View on PubMed)

Garrison SR, Bakal JA, Kolber MR, Korownyk CS, Green LA, Kirkwood JEM, McAlister FA, Padwal RS, Lewanczuk R, Hill MD, Singer AG, Katz A, Kelmer MD, Gayayan A, Campbell FN, Vucenovic A, Archibald NR, Yeung JMS, Youngson ERE, McGrail K, O'Neill BG, Greiver M, Manca DP, Kraut RY, Wang T, Manns BJ, Mangin DA, MacLean C, McCormack J, Wong ST, Norris C, Allan GM. Antihypertensive Medication Timing and Cardiovascular Events and Death: The BedMed Randomized Clinical Trial. JAMA. 2025 Jun 17;333(23):2061-2072. doi: 10.1001/jama.2025.4390.

Reference Type: DERIVED

PMID: 40354045 (View on PubMed)

Garrison SR, Kelmer M, Korownyk T, Kolber MR, Allan GM, Bakal J, Singer A, Katz A, Mcalister F, Padwal RS, Lewanczuk R, Hill MD, McGrail K, O'Neill B, Greiver M, Manca DP, Mangin D, Wong ST, Kirkwood JEM, McCormack JP, Yeung JMS, Green L. Tolerability of bedtime diuretics: a prospective cohort analysis. BMJ Open. 2023 Jun 6;13(6):e068188. doi: 10.1136/bmjopen-2022-068188.

Reference Type: DERIVED

PMID: 37280022 (View on PubMed)

Garrison SR, Kolber MR, Allan GM, Bakal J, Green L, Singer A, Trueman DR, McAlister FA, Padwal RS, Hill MD, Manns B, McGrail K, O'Neill B, Greiver M, Froentjes LS, Manca DP, Mangin D, Wong ST, MacLean C, Kirkwood JE, McCracken R, McCormack JP, Norris C, Korownyk T. Bedtime versus morning use of antihypertensives for cardiovascular risk reduction (BedMed): protocol for a prospective, randomised, open-label, blinded end-point pragmatic trial. BMJ Open. 2022 Feb 24;12(2):e059711. doi: 10.1136/bmjopen-2021-059711.

Reference Type: DERIVED

PMID: 35210352 (View on PubMed)

Related Links

http://pragmatictrials.ca/

The Pragmatic Trials Collaborative

Other Identifiers

BedMed Nov 30 2016

Identifier Type: -

Identifier Source: org_study_id