Epidemiology of Long QTand Asian Sudden Death in Sleep

April 26, 2021 updated by: Utah State University
To conduct a cross-sectional epidemiologic study of the determinants of prolonged heart rate corrected QT interval (QTc) among 300 men and 300 woman in the population with the highest known risk of SUDS: Southeast Asian refugees in Thailand. .

Study Overview

Detailed Description

BACKGROUND:

Sudden and unexplained death in sleep (SUDS) is a leading cause of death of young men in several Asian populations. The immediate cause is ventricular fibrillation in the absence of known disease. A strong environmental component may be inferred from the regional nature of SUDS in groups that are culturally and genetically distinct and the rapid decline in rates of SUDS after migration of Southeast (SE) Asian refugees to the United States. Risk of SUDS rises sharply to a peak among men aged 35 years of age, then declines with increasing age. In a pilot studies of SE Asian refugee men in Thailand with the highest known risk of SUDS, the investigators documented high-prevalences of prolonged heart rate corrected QT interval (QTc), thiamine deficiency, hypokalemia, and a positive association between poor thiamine status, measured by erythrocyte transketolase activity (ETK), and QTc. These limited studies were unable to precisely quantify the relationship between QTc and thiamine status, lacked sufficient power to examine the relationship between QTc and hypokalemia, did not include other electrolytes, and did not address the striking differences in risk of SUDS by sex and age.

DESIGN NARRATIVE:

The study was cross-sectional in design. During a 14-month period, informed consent was obtained from subjects selected in an age-stratified random sample of refugees scheduled for routine medical screening. Blood samples, 12-lead and 24-hour ECGs, and interview data were collected to test the following hypotheses: (1) mean QTc was greater in men than women, (2) mean QTc was greater in men aged 30-39 years than in men younger or older; no similar relationship was expected among women, (3) QTc was positively correlated with poor thiamine status, measured by erythrocyte transketolase activity, (4-6) QTc was negatively correlated with serum levels of potassium, magnesium, and total calcium, and (7) QTc was associated with abnormalities of autonomic control of the heart, as indicated by power spectral analysis of heart rate variability. Secondary aims included studying interactions of thiamine status and electrolytes in the prolongation of QTc, dynamic analysis of QT variation by heart rate level in 24-hr ECGs, and collection of blood specimens for later genetic studies

Study Type

Observational

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

1 year to 98 years (Child, Adult, Older Adult)

Accepts Healthy Volunteers

No

Genders Eligible for Study

Male

Description

No eligibility criteria

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Investigators

  • Ronald Munger, Utah State University

Publications and helpful links

The person responsible for entering information about the study voluntarily provides these publications. These may be about anything related to the study.

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start

February 1, 1993

Study Completion

January 1, 1995

Study Registration Dates

First Submitted

May 25, 2000

First Submitted That Met QC Criteria

May 25, 2000

First Posted (Estimate)

May 26, 2000

Study Record Updates

Last Update Posted (Actual)

April 27, 2021

Last Update Submitted That Met QC Criteria

April 26, 2021

Last Verified

March 1, 2005

More Information

Terms related to this study

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

No

Studies a U.S. FDA-regulated device product

No

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

Clinical Trials on Heart Diseases

3
Subscribe