Associations between continuous health examinations and trajectories of comorbidity of chronic disease: Evidence from a nationwide longitudinal study of middle-aged and older adults in China.

BACKGROUND

As population aging accelerates, the escalating prevalence of comorbidity of chronic diseases (CCD) necessitates evidence-based preventive strategies. This study aims to examine associations between continuous participation in health examinations and the long-term CCD trajectories among Chinese adults aged 45 and older, providing evidence to optimize targeted prevention.

METHODS

This study used data from four waves of China Health and Retirement Longitudinal Study (CHARLS), specifically 2013, 2015, 2018, and 2020. Latent class growth analysis was used to classify trajectories of CCD. Chi-square tests and multivariate logistic regression were conducted to examine the relationship between CCD and health examination behaviors. A regression discontinuity design was also implemented to assess the impact of China's free health examination policy.

RESULTS

A total of 12,510 participants data were categorized into six latent classes. In the unadjusted model, continuous health examination participants were significantly more likely to be classified into the Health Risk (Relative risk ratio (RRR) = 2.249; 95% CI: 1.780-2.842) and Multiple Chronic Diseases Worsening groups (RRR = 7.124; 95% CI: 5.454-9.305) compared to non-participants. After adjusting for baseline burden, individuals with a low baseline burden who participated in health examination had a lower likelihood of unfavorable CCD trajectories (RRR = 0.456; 95% CI: 0.278-0.748; P < 0.01) than non-participants. Older adults were more likely to participate in continuous examinations (OR = 21.571; 95% CI: 11.732-39.662). After controlling for sociodemographic factors, the association between continuous health examinations and CCD trajectories varied by baseline burden, showing stronger effects in individuals with lower baseline burden and weaker effects in those with higher burden (P < 0.01).

CONCLUSIONS

Continuous health examinations are significantly associated with CCD trajectories. However, their effectiveness remains moderated by baseline disease burden. The current free health examination policy effectively fosters CCD management, yet this association is contingent upon age and socioeconomic determinants. The extension of eligibility to individuals below 65 could maximize the potential for early chronic disease control. This may also serve as a valuable blueprint for other low- and middle-income countries for optimizing cost-effectiveness of their preventive healthcare systems before populations age into high-burden morbidity.