Study Title
Effect of a 2-hour interval between dinner and bedtime on glycated haemoglobin levels in middle-aged and elderly Japanese people: a longitudinal analysis of 3-year health check-up data.
Principal Investigator
Su Su Maw, Chiyori Haga.
Affiliation
Okayama University.
Start Date
April 2012.
End Date
March 2014.
Study Objective
To investigate whether a 2-hour interval between dinner and bedtime affects glycated haemoglobin (HbA1c) levels in middle-aged and elderly Japanese individuals without pre-diabetic or diabetic conditions.
Short Abstract
This study aimed to assess the relationship between the time interval between dinner and sleep and its impact on HbA1c levels among middle-aged and elderly Japanese people. The findings suggest that ensuring a 2-hour interval between dinner and bedtime did not significantly influence HbA1c levels. Factors like smoking, alcohol consumption, and BMI had a more notable impact on HbA1c trajectories.
Study Design
Longitudinal analysis of 3-year health check-up data using multilevel statistical models.
Population
1,573 participants aged 40 to 74 years, comprising self-employed and retired individuals.
Sample Size
1,573 participants in 2012, reduced to 1,032 in 2014 due to dropouts.
Inclusion Criteria
Individuals aged 40 to 74 years undergoing health check-ups, with no pre-existing diabetic or pre-diabetic conditions.
Exclusion Criteria
Individuals with abnormal HbA1c levels (≥6.1%) at baseline.
Intervention/Exposure
A comparison of individuals who slept within 2 hours after dinner and those who waited longer, with analysis of their HbA1c levels over 3 years.
Outcome Measures
Changes in HbA1c levels, impact of lifestyle factors such as smoking, alcohol consumption, and BMI.
Funding Source
Supported by JSPS KAKENHI (Grant number: JP18K1102100).
Collaborating Institutions
None specified.
Ethics Approval
Approved by the Ethical Review Board of Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, and Okayama University Hospital.
Publication Status
Published in BMJ Nutrition, Prevention & Health, 2019.
Keywords
Glycated haemoglobin (HbA1c), dinner and bedtime interval, Japanese population, middle-aged, elderly, lifestyle factors.
Data Collection Methods
Health check-up data collected from 2012 to 2014, including lifestyle questionnaires and anthropometric measures.
Primary Data Availability
Data available through the Dryad repository (doi: 10.5061/dryad.kg183m5).
Contact Information
Su Su Maw, Community Health Nursing, Graduate School of Health Sciences, Okayama University,