From midlife emergence to old-age divergence: an empirical study on structural gendered ageism in health service utilization in Tibet

Population aging on the Tibetan Plateau may marginalize older women through combined gender and age bias. We measured sex-specific gaps in medical spending and service use across the life course. We tested whether gendered ageism appears in midlife and grows thereafter. We analyzed 1,274,491 person-year health insurance reimbursement claims data in three major Tibetan cities (2021–2023). We examined four outcomes: annual total medical expenditure, outpatient visits, inpatient admissions, and tertiary-hospital admissions. The key exposure was sex. Age was divided into seventeen five-year groups. We applied LASSO to prevent multicollinearity. We then estimated two-way fixed-effects models. These models controlled for Andersen’s predisposing, enabling, and need covariates. We clustered errors at the person level. Women’s spending gap appeared at ages 36–40 (β = − 299; 95% CI: − 425 to − 123). This gap represented roughly an 8% lower annual expenditure compared with men. The maximum deficit occurred at ages 71–75 (β = − 1,006; 95% CI: − 1,401 to − 610), with women spending 28% less than men. Women’s outpatient advantage peaked at ages 31–35 (β = 0.58; 95% CI: 0.54 to 0.61). This advantage faded after age 70. In the inpatient admissions model, women first showed a significant advantage at age 31–35 (β = 0.02 admissions). From age 46–50 through 61–65, this advantage ranged from 0.03 to 0.05 admissions. From age 36–40 onward, women had fewer tertiary-hospital admissions than men (β = − 0.01). This deficit persisted across all later age bands. Gendered ageism emerges 30 years earlier than the conventional “65-plus” threshold. It accelerates through midlife and peaks in late old age among Tibetan women. Early policy action could interrupt this cumulative inequity. We recommend higher URRBMI reimbursement, “Plateau-Women-First” telemedicine channels, and flexible delayed retirement with pension top-ups. These measures would support gender-sensitive healthy aging.