Trajectories network analysis of chronic diseases among middle-aged and older adults: evidence from the China Health and Retirement Longitudinal Study (CHARLS).

BACKGROUND: Given the increased risk of chronic diseases and comorbidity among middle-aged and older adults in China, it is pivotal to identify the disease trajectory of developing chronic multimorbidity and address the temporal correlation among chronic diseases. METHOD: The data of 15895 participants from the China Health and Retirement Longitudinal Study (CHARLS 2011 - 2018) were analyzed in the current study. Binomial tests and the conditional logistic regression model were conducted to estimate the associations among 14 chronic diseases, and the disease trajectory network analysis was adopted to visualize the relationships. RESULTS: The analysis showed that hypertension is the most prevalent disease among the 14 chronic conditions, with the highest cumulative incidence among all chronic diseases. In the disease trajectory network, arthritis was found to be the starting point, and digestive diseases, hypertension, heart diseases, and dyslipidemia were at the center, while memory-related disease (MRD), stroke, and diabetes were at the periphery of the network. CONCLUSIONS: With the chronic disease trajectory network analysis, we found that arthritis was prone to the occurrence and development of various other diseases. In addition, patients of heart diseases/hypertension/digestive disease/dyslipidemia were under higher risk of developing other chronic conditions. For patients with multimorbidity, early prevention can preclude them from developing into poorer conditions, such as stroke, MRD, and diabetes. By identifying the trajectory network of chronic disease, the results provided critical insights for developing early prevention and individualized support services to reduce disease burden and improve patients' quality of life.

Relationship between physical activity and mental health in a national representative cross-section study: Its variations according to obesity and comorbidity.

BACKGROUND: Physical activity is positively associated with mental health in obese people with chronic comorbidities. However, how physical activity types (PATs), physical activity frequency (PAF), and physical activity duration (PAD) are associated with mental health need to be further clarified. The current study investigated and compared the effectiveness of PATs, physical activity frequency PAF and PAD for mental health in obese people with various chronic comorbid conditions. METHODS: This cross-sectional study included 871,919 adults who participated in the Behavioral Risk Factor Surveillance System (BRFSS). They were divided into four groups: healthy people, obese people with 0, 1, and 2+ chronic comorbid conditions. The zero-inflated negative binomial (ZINB) regression model and the generalized additive model were used to explore the association between physical activity and mental health burden in the four groups, respectively. RESULTS: Jogging (30.00%), hiking (28.36%) and bicycling (28.32%) have greater improvement in mental health of healthy people; jogging (19.25%), golf (19.95%) and bicycling machine exercise (19.13%) showed a greater improvement in mental health of obese people with no chronic comorbid condition; and aerobic exercise videos or class showed a greater improvement in mental health of obese people with one chronic comorbid condition (22.14%) and obese people with two or more chronic comorbid conditions (19.60%). Non-linear relationships were observed between PAF, PAD, and energy expenditure and mental health. The healthy participants who exercised about 10-15 times a month and 40-50 min per session or about 400-600 METs-min per week had greater benefits for mental health. However, the lowest point of the smooth curve moved to the left with an increasing number of chronic comorbid conditions in obese people. CONCLUSIONS: Almost all PATs were associated with better mental health, but their benefits decreased with increasing number of chronic comorbid conditions in obese people. There were U-shaped relationships between mental health and weekly physical activity frequency, duration, and METs-min.