Physical Activity, Sunshine Duration, and Osteoporotic Fractures: A Nested Case-Control Study.

Area of Science:

• Epidemiology
• Gerontology
• Public Health

Background:

• Osteoporotic fractures pose a significant health burden, particularly vertebral, hip, and distal radius fractures.
• Physical activity (PA) and sunshine duration (SD) are recognized factors influencing bone health and fracture risk.
• Understanding the combined effects of PA and SD on specific fracture sites is crucial for targeted prevention strategies.

Purpose of the Study:

• To investigate the associations between combined physical activity (PA) and sunshine duration (SD) and the occurrence of osteoporotic fractures.
• To analyze the risk of vertebral, hip, and distal radius fractures based on different levels of PA intensity and SD.
• To determine if combined PA and SD influence the incidence of osteoporotic fractures.

Main Methods:

• Utilized data from the Korean National Health Insurance Service-National Health Screening Cohort and the Korea Meteorological Administration.
• Included 12,103 osteoporotic fracture cases (vertebral, hip, distal radius) and 24,206 matched controls.
• Employed conditional logistic regression to calculate odds ratios (ORs) for combined PA and SD groups.

Main Results:

• Higher intensity PA (moderate- to high-intensity) combined with either short or long SD was associated with a reduced risk of vertebral fractures (ORs 0.83-0.84) compared to low PA and short SD.
• No significant associations were found between combined PA and SD groups and the occurrence of hip or distal radius fractures.
• The findings suggest an inverse relationship between higher PA intensity and the risk of vertebral fractures.

Conclusions:

• Higher intensity physical activity is inversely associated with the risk of vertebral fractures.
• The combination of physical activity intensity and sunshine duration may play a role in vertebral fracture prevention.
• Further research is warranted to explore the specific mechanisms and optimal levels of PA and SD for preventing different types of osteoporotic fractures.