OBJECTIVES The purpose of this study is to examine time trends in Health-Related Quality of Life (HQoL) among U.S. adults and to analyze the time-varying associations between Leisure-Time Physical Activity (LTPA) and HQoL.
METHODS This study utilized data from the Behavioral Risk Factor Surveillance System (BRFSS) collected between 2018 and 2023. For the trend analysis of HQoL, a weighted intercept-only linear Time-Varying Effect Model (TVEM) was employed. To examine the temporal association between LTPA and HQoL, a weighted logistic TVEM was applied. Furthermore, a weighted logistic TVEM was used to assess the moderating effect of sex (male vs. female) on the relationship between LTPA and HQoL.
RESULTS A total of 1,883,016 U.S. adults were included in the analysis. The mean number of unhealthy days increased from 2018 to 2019, reaching 8.83 days, then declined to 7.45 days in 2020. By late 2023, the mean number of unhealthy days reached its highest level over the study period at 9.06 days. From 2018 to 2023, the association between LTPA and HQoL remained stable over time. After adjusting for time-invariant covariates, a significant association between engaging in LTPA and better HQoL was confirmed. Additionally, sex-stratified analysis revealed that both men and women exhibited the strongest association in 2018. However, no statistically significant sex-based moderation effect was observed.
CONCLUSIONS The findings of this study confirmed that the mean number of unhealthy days among U.S. adults showed a fluctuating pattern from 2018 to 2023, with the highest levels observed in late 2023. Throughout the study period, LTPA was consistently associated with higher odds of reporting better HQoL, and this association remained stable across time with no evidence of sex-stratified moderation. These findings highlight the potential public health relevance of maintaining regular LTPA to support perceived well-being during periods of societal disruption