While pain is common in older adults, the association with physical activity is unclear. Currently, the role physical activity plays in impacting pain developing over time is not well-defined.
Latent transition analysis (LTA) is a model-based approach to identifying underlying subgroups in a population, longitudinally, based on measured characteristics. In this study LTA was used to explore the associations between physical activity levels and pain classes of adults aged over 50 years, from the Irish Longitudinal Study on Ageing (n=8,175) across three waves of data collection (4 years).
Using three previously established pain classes (No Pain; Low-Moderate Impact Pain; High Impact Pain), 66% of older adults were classified as having 'No Pain' across the three waves. At Wave 1, individuals reporting low (OR = 4.00, 95% CI =3.21, 5.17) or moderate (OR = 1.59, 95% CI = 1.27, 1.99) levels of physical activity are more likely to be in the High Impact Pain class, than the No Pain class. Longitudinally, individuals in the No Pain class with low or moderate physical activity, were more likely to transition to the High Impact Pain class, compared to those with higher physical activity scores (from Wave 1 to Wave 2, OR = 1.90, 95% CI=1.15, 3.37; and from Wave 2 to Wave 3, OR = 2.27, 95% CI=1.40, 4.74).
Older adults who do not meet minimum physical activity guidelines for moderate intensity exercise are at increased risk of higher impact pain when followed over four years.