Objectively measured physical activity and sedentary time in young adults born preterm-The ESTER study
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Published on: July 27, 2022
Marjaana Tikanmäki1,2, Tuija Tammelin3, Nina Kaseva1
1Department of Health, Chronic Disease Prevention Unit, National Institute for Health and Welfare, Oulu and Helsinki, Finland.
Insights
Young adults born preterm do not show differences in objectively measured physical activity or sedentary time compared to those born at term. Previous findings may stem from self-reported activity levels, not objective measures.
Area of Science:
- Cardiology
- Pediatrics
- Public Health
Background:
- Young adults born preterm exhibit elevated cardio metabolic risk factors and report lower physical activity.
- Physical activity is crucial for maintaining cardio metabolic health.
- Preterm birth may impact long-term physical activity and sedentary behavior.
Purpose of the Study:
- To investigate objectively measured physical activity and sedentary time in young adults born preterm versus those born at term.
- To test the hypothesis that preterm-born individuals have lower physical activity and higher sedentary time.
Main Methods:
- A cohort of 23.3-year-old adults from the ESTER birth cohort study was analyzed.
- Participants included early preterm (<34 weeks), late preterm (34-36 weeks), and term-born controls.
- Physical activity and sedentary time were objectively measured using hip-worn accelerometers.
Main Results:
- No significant differences in physical activity levels (measured in counts per minute) were found between preterm-born adults and term-born controls.
- Time spent sedentary was also similar across all groups (early preterm, late preterm, and term-born).
- Statistical adjustments for early life factors and current characteristics did not alter these findings.
Conclusions:
- The study contradicts the hypothesis, showing no difference in objectively measured physical activity or sedentary time between preterm-born and term-born young adults.
- Reported disparities in physical activity in previous studies may be attributable to self-reporting biases.
- Objective measurement is key to understanding the physical activity patterns of adults born preterm.
Background:
Young adults born preterm have higher levels of cardio metabolic risk factors and they report less physical activity than their peers born at term. Physical activity provides important cardio metabolic health benefits. We hypothesized that objectively measured physical activity levels are lower and time spent sedentary is higher among preterm-born individuals compared with controls.
Methods:
We studied unimpaired participants of the ESTER birth cohort study at age 23.3 y (SD: 1.2): 60 born early preterm (<34 wk), 108 late preterm (34-36 wk), and 178 at term (controls). Physical activity and sedentary time were measured by hip-worn accelerometer (ActiGraph).
Results:
As compared with controls' (mean physical activity, 303 counts per minute (cpm; SD 129)), physical activity was similar among adults born early preterm (mean difference = 21 cpm, 95% CI -61, 19) or late preterm (5 cpm, -27, 38). Time spent sedentary was also similar. Adjustments for early life confounders or current mediating characteristics did not change the results.
Conclusion:
In contrast to our hypothesis, we found no difference in objectively measured physical activity or time spent sedentary between adults born preterm and at term. The previously reported differences may be limited to physical activity captured by self-report.
