BMI change patterns linked to hospitalization risk in prospective cohort of 20,329 high-risk Chinese adults

In a prospective cohort of 20,329 adults at high cardiovascular risk in China’s Anhui region, four body mass index (BMI) change patterns were associated with different risks of hospitalization. People whose BMI increased rapidly from a normal baseline had higher risks of both all-cause and cardiovascular disease (CVD) hospitalization than those whose weight remained stable at a normal BMI. A group characterized by persistent obesity and rapid weight loss also had elevated all-cause hospitalization risk, while its association with CVD hospitalization was borderline and its confidence interval included no difference.

The findings are summarized in the published abstract of a study drawing on the China PEACE Million Persons Project between 2017 and 2023. Participants were considered at high cardiovascular risk if they had a history of cardiovascular disease, hypertension or dyslipidemia, or a 10-year CVD risk of at least 20%. Investigators used K-means clustering to identify BMI trajectories from baseline BMI and the annual rate of BMI change. Multivariable Cox models then assessed associations between those trajectories and the primary outcomes of all-cause and CVD hospitalization. During a median follow-up of 3.6 years, the study recorded 2,272 all-cause hospitalizations and 617 CVD hospitalizations.

Four trajectories were identified. The largest, comprising 50.9% of participants, was normal weight-stable. Rapid gainers accounted for 4.4% and had a normal baseline BMI with a median annual increase of 1.80 kg/m² per year. Obese-slow losers represented 39.5%, remaining obese with minimal weight reduction and a median annual change of −0.20 kg/m² per year. Obese-rapid losers made up 4.9%; this group had the highest baseline BMI and a median annual change of −2.20 kg/m² per year.

Compared with normal weight-stable participants, rapid gainers had an adjusted hazard ratio of 1.44 (95% confidence interval [CI] 1.10–1.88) for all-cause hospitalization, while obese-slow losers had an adjusted hazard ratio of 1.17 (95% CI 1.07–1.28). Obese-rapid losers also had higher all-cause hospitalization risk, with an adjusted hazard ratio of 1.39 (95% CI 1.09–1.78). For CVD hospitalization, the association was significant among rapid gainers, with an adjusted hazard ratio of 1.86 (95% CI 1.16–2.96), and obese-slow losers, with an adjusted hazard ratio of 1.26 (95% CI 1.06–1.50). The corresponding estimate for obese-rapid losers was 1.57 (95% CI 0.97–2.54), which the abstract described as borderline.

The results are observational associations and do not establish that BMI changes caused the hospitalization outcomes. The obese-rapid-loser group had higher socioeconomic status but also a greater burden of comorbidity, complicating interpretation of its elevated all-cause risk. The study’s scope was limited to adults at high CVD risk in Anhui, and the available source is the article abstract rather than a full assessment of the published paper. The authors concluded that rapid weight loss among people with obesity was not uniformly associated with favorable hospitalization outcomes and called for evaluation of the nature of weight loss, not only its magnitude.

Subject of Research: Associations between BMI change patterns and hospitalization risk among high-cardiovascular-risk adults in Anhui, China

Article Title: Body mass index change patterns and risk of hospitalization among populations at high cardiovascular risk: findings from the China PEACE Million Persons Project

Article References: Wang, Q., Wang, K., Liu, Z., Wu, G., Yuan, F., & Chen, K. (2026). Body mass index change patterns and risk of hospitalization among populations at high cardiovascular risk: findings from the China PEACE Million Persons Project. BMC Public Health. https://doi.org/10.1186/s12889-026-29855-z

Image Credits: AI Generated

DOI: 10.1186/s12889-026-29855-z

Keywords: body mass index, BMI trajectories, hospitalization risk, cardiovascular disease, high-risk adults, prospective cohort, weight change, China, Body, mass, index, change