Older adults are particularly vulnerable to the cardiovascular effects of short-term ambient temperature exposure. However, evidence remains limited on the

Medical payment plans shape financial protection and access to care, but their associations with costs, disease progression and survival in hypertension remain poorly characterised. We analyse 8,004,039 inpatient admissions among 4,675,738 patients in Henan, China, from 2019 to 2024 using mixed-effects, multistate and survival models, and externally validate the non-mortality findings in Xinjiang. Compared with self-pay, urban employee, urban-rural resident and commercial or other insurance are associated with 24.95%, 8.71% and 16.64% higher total inpatient expenditure, respectively, while all non-self-pay plans are associated with 89.47–97.56% lower out-of-pocket spending. Urban employee insurance shows the most favourable survival (adjusted hazard ratio for all-cause mortality, 0.72; 95% confidence interval, 0.68–0.76), whereas government-supported or medical assistance arrangements show the poorest survival (1.33; 1.23–1.43) and the greatest expected time in multimorbidity. Sensitivity analyses and external validation support the direction of the main non-mortality findings. These observational associations do not isolate payment-plan effects and may reflect differences in benefit scope, care access and participants’ underlying health and social vulnerability. Narrowing reimbursement gaps alone may therefore be insufficient without broader improvements in service coverage and access.