Prevalence of Sub-Clinical Atrial Fibrillation in Elderly Patients With Hypertension, Detected Using an External Loop Recorder (ASSERT-III)

Prevalence of Sub-Clinical Atrial Fibrillation in Elderly Patients With Hypertension, Detected Using an External Loop Recorder Using Automatic Algorithms for AF Detection: A Pilot Study (ASSERT-III)

The ASSERT-III study aims to determine the incidence of sub-clinical (silent) atrial fibrillation (AF) among elderly patients with hypertension and at least one other risk factor for AF. This will be accomplished by monitoring with a wireless external loop monitor for 30 to 60 days.

Study Overview

• Status: Completed
• Conditions: Hypertension; Elderly; Risk Factors for Atrial Fibrillation

• Study Type: Observational
• Enrollment (Actual): 129

Contacts and Locations

Study Locations

• Canada
  • Ontario
    • Burlington, Ontario, Canada, L7R 1E2
      • AVIVA Medical Diagnostics and Specialist Clinic Inc.
    • Hamilton, Ontario, Canada, L8M 1K7
      • Hamilton Medical Research Group
    • Hamilton, Ontario, Canada
      • Family Practice - Drs. Cameron, Crombie & Croft
    • Oakville, Ontario, Canada, L6H 7S8
      • OakMed Family Health Team

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 80 years and older (Older Adult)
• Accepts Healthy Volunteers: No

• Sampling Method: Non-Probability Sample

Study Population

elderly patients attending primary care clinic or ambulatory resident of a chronic care facility, with hypertension and at least one addional risk factor for developing AF.

Description

Inclusion Criteria:

Patients will be eligible for inclusion if they meet all of the following:

1. Age ≥ 80 years
2. History of hypertension OR a blood pressure of ≥ 140/90 mmHg
3. Attending a primary care clinic, OR ambulatory resident of a chronic care facility

4. At least one of the following additional risk factors for developing AF:

   1. Diabetes
   2. Body mass index ≥ 30
   3. History of smoking
   4. Documented Obstructive sleep apnea
   5. Cardiovascular disease
   6. Heart Failure
   7. Left ventricular hypertrophy (on ECG or echocardiography)
5. Provide written informed consent

Exclusion Criteria:

1. ECG documented history of AF or atrial flutter, with an episode duration ≥ 6 minutes
2. Existing implanted pacemaker or defibrillator

3. Patients considered by the investigator to be unsuitable for study follow-up because the patient:

   1. is unreliable concerning the requirements for follow-up during the study and/or compliance with the use of the external loop recorder
   2. has a life expectancy less that the expected study duration due to concomitant disease
   3. has a condition which in the opinion of the investigator, would not allow current chronic treatment with anticoagultion -

Study Plan

How is the study designed?

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Occurance of atrial fibrillation episode	Detection rate of sub-clinical atrial fibrillation episodes, at least 6 minutes in duration	within 30 - 60 days of follow-up

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Tolerability and feasibility of long term monitoring in elderly patients	The tolerability of long-term monitoring in elderly patients and the ability of these patients to manually transmit data to the cardiac analyses centre.	30 - 60 days of follow-up
Proportion of patients eligible to receive anticoagulation		30 - 60 days of follow-up
AF Burden	An estimate of the burden of atrial arrhythmias (from device logs) in patients with AF.	30 - 60 days of follow-up

Collaborators and Investigators

• Sponsor: Population Health Research Institute
• Collaborators: Bristol-Myers Squibb; Pfizer; M-Health Solutions
• Investigators: Principal Investigator: Jeff Healey, M.D., Population Health Research Institute; Principal Investigator: Stuart Connolly, M.D., Population Health Research Institute

Study record dates

Study Major Dates

• Study Start: January 1, 2014
• Primary Completion (Actual): March 1, 2015
• Study Completion (Actual): March 1, 2015

Study Registration Dates

• First Submitted: November 3, 2014
• First Submitted That Met QC Criteria: March 24, 2015
• First Posted (Estimated): March 30, 2015

Study Record Updates

• Last Update Posted (Actual): June 4, 2025
• Last Update Submitted That Met QC Criteria: June 1, 2025
• Last Verified: April 1, 2015

More Information

Terms related to this study

• Keywords: atrial fibrillation; elderly; hypertension; primary care; risk factors
• Additional Relevant MeSH Terms: Vascular Diseases; Cardiovascular Diseases; Pathologic Processes; Heart Diseases; Arrhythmias, Cardiac; Hypertension; Atrial Fibrillation
• Other Study ID Numbers: ASSERT-III