Objective
To investigate the relationship between physical activity and the severity of menopausal symptoms in middle-aged women in northwest China.
Methods
This was a cross-sectional online survey study. Using a snowball sampling method, 468 women aged 45 to 60 were recruited from northwest China and their demographic information was collected. The modified Kupperman Menopausal Index scale and International Physical Activity Questionnaire short form were used in this study. Random forest was used to rank the importance of variables and select the optimal combination. The direction and relative risk (odds ratio value) of selected variables were further explained with an ordinal logistic regression model.
Results
The prevalence of menopausal syndromes was 74.8% and more than one-half of the participants had moderate or severe symptoms (54.3%). The Mantel-Haenszel linear-by-linear chi-square test showed a strong and negative correlation between physical activity level and the severity of menopausal symptoms (P < 0.001). Random forest demonstrated that the physical activity level was the most significant variable associated with the severity of menopausal symptoms. Multiple random forest regressions showed that the out-of-bag error rate reaches the minimum when the top 4 variables (physical activity level, menopausal status, perceived health status, and parity) in the importance ranking form an optimal variable combination. Ordinal logistic regression analysis showed that a higher physical activity level and a satisfactory perceived health status might be protective factors for menopausal symptoms (odds ratio (OR) < 1, P < 0.001); whereas perimenopausal or postmenopausal status and 2 parities might be risk factors for menopausal symptoms (OR > 1, P < 0.001).
Conclusions
There is a strong negative correlation between physical activity and the severity of menopausal symptoms. The results have a clinical implication that the menopausal symptoms may be improved by the moderate-to-high level physical activity in the lives of middle-aged women.