The compounding burden of disability in Mexico: social protection gaps, chronic disease excess, and prospective mortality from national open data sources

Background Persons with disabilities (PWD) face disproportionate barriers to social protection and healthcare worldwide, yet comprehensive multi-source evidence linking social security coverage, morbidity, and mortality outcomes remains scarce in Latin America. Methods We conducted a cross-sectional, multi-source population-based study with a prospective cohort component, integrating nine nationally representative Mexican data sources (2017–2023) encompassing over 125 million persons. Disability was operationalized using source-specific measures, including Washington Group-based instruments where available. We examined social security coverage disparities, catastrophic health expenditure, chronic disease prevalence, intersectional exclusion, prospective three-year mortality, and geographic overlap with healthcare infrastructure deficits. Survey-weighted logistic regression with progressive adjustment, Benjamini–Hochberg correction for multiple comparisons, and unweighted binomial models for prospective mortality were employed. Results Among 6.8 million PWD in the 2020 Census, apparent social security coverage advantages reflected a structural shift to non-contributory programs driven by older age structure; after demographic adjustment the advantage disappeared (OR = 0.99, p = 0.30), with a modest residual protective effect after full adjustment (OR = 0.92, p < 0.001). Disability compounded exclusion for women (interaction OR = 1.07) and indigenous persons (interaction OR = 1.10; both p < 0.001). Catastrophic health expenditure was higher among PWD households (adjusted OR = 2.02). Disease prevalence was significantly higher across all nine conditions assessed (adjusted ORs ranging from 1.46 for diabetes to 2.92 for depressive symptomatology), with less than 5% attenuation after adjustment. Prospective three-year mortality was elevated (adjusted OR = 3.77; 95% CI: 3.02–4.70; risk ratio 3.0), with a severity gradient reaching OR = 7.24. Non-contributory coverage was not associated with lower mortality (OR = 0.89, p = 0.32). Geographic analysis ecologically estimated approximately 502,858 triple-vulnerable PWD concentrated in high-marginalization states. Conclusions The apparent social security advantage of PWD is an artifact of older age structure and a shift toward non-contributory programs that confer nominal affiliation without a detectable mortality benefit in this older-adult cohort, with disadvantage intensifying for indigenous women with disability. Expanding enrollment alone is likely insufficient: closing this gap requires disability-inclusive coverage that translates affiliation into effective protection.