The self-rated health can predict the onset of multimorbidity based on a longitudinal study in Northwestern China

Multimorbidity significantly amplifies the risk of disability and mortality and has become a global health challenge. However, awareness of multimorbidity remains notably low, particularly in low-income countries and rural areas. This study aimed to investigate whether self-rated health (SRH) could predict the future risk of multimorbidity and its distinct patterns. This study included 7837 individuals aged ≥ 18 years from the 2015–2022 wave of the “Innovating Payment System to Enhance Healthcare Efficiency” project. We categorized SRH into “good” and “poor” groups. Multimorbidity was defined as the coexistence of two or more chronic diseases in a single individual, assessed via self-reported of 12 diseases. We used logistic regression models to analyze the risk of developing multimorbidity during a 7.3-year follow-up period across different groups at baseline. We employed propensity score matching to balance covariates effects, latent class analysis to identify multimorbidity patterns, and multiple logistic regression to examine the association between SRH groups and multimorbidity patterns. We performed several sensitivity analyses to validate the robustness of the results. In 2015, 19.74% of adults reported poor SRH. By 2022, 795 individuals had developed multimorbidity, resulting in a cumulative incidence rate of 10.14%. Individuals with poor SRH exhibited 1.48 times (95 CI %: 1.24–1.77) higher risk of developing multimorbidity compared to those with good SRH after adjusting for covariates. We identified 3 latent classes of multimorbidity: the health group (90.1%), the vascular disease group (5.1%), and the digest-skeletal disease group (4.8%). The risk of digest-skeletal disease was 1.52 times higher than that of the health group after adjusting for covariates. Sensitivity analyses showed that all results were robust, except that adjustment for alcohol consumption affected the association with the vascular disease group. SRH is associated with further multimorbidity risk and its distinct patterns among adults aged 18 years and older in Northwestern China. As a simple, self-reported, and cost-free measure, SRH offers a pragmatic screening tool uniquely suited for resource-limited rural settings where clinical assessments are unavailable. This study provides novel evidence for integrating SRH-based risk stratification into primary care, facilitating early detection and targeted prevention to reduce multimorbidity-related burden.