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Prevalence of Resistant Hypertension With DOT

The Prevalence of Pseudo-resistant Hypertension Using the Direct Observed Therapy Test: A Prospective Observational Study

Status
Completed
Phases
Unknown
Study type
Observational
Source
ClinicalTrials.gov
Registry ID
NCT02513524
Acronym
DOT
Enrollment
60
Registered
2015-07-31
Start date
2015-09-30
Completion date
2018-09-30
Last updated
2019-03-21

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Hypertension

Keywords

hypertension, adherence, resistant hypertension, blood pressure, non-adherence

Brief summary

High blood pressure is a risk factor for bad clinical events, such as heart failure, stroke, kidney failure and death. This risk is much higher in those with 'resistant' hypertension, in whom the blood pressure remains high despite more than 3 blood pressure medicines. Current estimates of the proportion of individuals with resistant hypertension may be an overestimate, since some of them are not actually adherent (i.e. not taking the medicines they are prescribed). Methods to detect non-adherence, such as asking the patient, counting pills, and getting records from pharmacy are not fool proof. Direct observed therapy (where patients are administered medicines under observation by a health care personnel) is quite useful to diagnose this, and is the standard of care in the Renal Hypertension Clinic, before more tests and interventions (such as CT scans, renal angiogram) are performed. In this study, the investigators will measure the proportion of patients with resistant hypertension who are non-adherent based on direct observed therapy, and follow them up to examine the impact of this diagnosis.

Detailed description

This is a prospective, observational study. Patients fitting inclusion and exclusion criteria, after informed consent, will undergo the direct observed therapy test in the hypertension unit (this is usual care in the unit, which they will undergo even if they are not part of the study). The Direct Observation Therapy (DOT) Test includes the following components: 1. Administer and observe ingestion of usual morning antihypertensive medications. 2. Monitor BP every 30 minutes, using 5 readings of an automated oscillometric BP device ( BP-TRU), until plateau affect achieved, defined as 3 consecutive cycles of BP readings declining by less than 10 mmHg per cycle). 3. Registered Nurse (RN) repeats standing BP prior to initiation of 24 hour Ambulatory Blood Pressure Monitoring(ABPM). 4. RN initiates 24 hour ABPM In addition, participants will undergo an additional 24-hour ABPM test 1 month after the DOT test is undertaken.

Interventions

PROCEDUREDirect Observed Therapy test

There is one group only, all of whom will undergo direct observed therapy testing

Sponsors

Ottawa Hospital Research Institute
Lead SponsorOTHER

Study design

Observational model
COHORT
Time perspective
PROSPECTIVE

Eligibility

Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
No

Inclusion criteria

1. Age 18 years or older 2. Confirmed resistant hypertension defined as daytime BP readings above 135/85 mmHg (confirmed by 24-hour ABPM results) using 3 or more BP lowering drugs 3. Adherence to medications confirmed by patient, and by hypertension clinic on basis of pharmacy filling record

Exclusion criteria

1. Pregnant patients 2. Inability to provide informed consent

Design outcomes

Primary

MeasureTime frameDescription
Prevalence of true resistant hypertension1 weekThe proportion of patients who continue to have resistant hypertension after administration of direct observed therapy, on the basis of the 24 hour ambulatory testing

Secondary

MeasureTime frameDescription
Prevalence of resistant hypertension at 1 month1 monthThe proportion of patients who continue to have resistant hypertension at one month, on the basis of the 24 hour ambulatory testing

Countries

Canada

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Feb 4, 2026