The Minha Casa Minha Vida social housing programme and leprosy in Brazil: an analysis of the 100 Million Brazilian Cohort (2010–2015)

Background: Ensuring housing interventions can contribute to improved living conditions which are strong socioeconomic determinants of leprosy. We estimated the association between the social housing programme Minha Casa Minha Vida (MCMVP) and leprosy new cases.

Methods: We followed families registered in the 100 Million Brazilian Cohort linked with MCMVP receipt and nationwide registries of leprosy between 2010 and 2015. We used Cox regression weighted by stabilized inverse probability of treatment weighting (IPTW) to assess the hazard ratio (HR) for the effect of MCMVP on leprosy. Weights were obtained by propensity score using demographic and socioeconomic covariates at baseline. Sensitivity analyses were done considering potential delays to receiving MCMVP, municipality of residence population size and by controlling by the baseline risk of leprosy among potential recipients.

Results: We followed up 24,584,768 individuals, of which 618,883 (2.5%) were MCMVP recipients, and detected 8,874 new leprosy cases during the study period. Leprosy incidence was higher among MCMVP recipients (13.32/100,000 pyr; 95%CI = 11.45–15.49) compared to non-recipients (11.72/100,000 pyr; 95%CI = 11.47–11.97). MCMVP recipients had higher leprosy incidence (HR = 1.66; 95%CI = 1.34–2.06), compared to non-recipients. Point estimates were lower when considering a delay of 6 or 12 months to moving into the new household (HR = 1.53; 95%CI = 1.20–1.95 and HR = 1.37; 95%CI = 1.05–1.78, respectively), in small/medium municipalities (≤ 300,000 inhabitants) (HR = 1.95; 95%CI = 1.51–2.52), and higher among individuals who subsequently became MCMVP beneficiaries before receiving the benefit (HR = 2.29; 95%CI = 1.93–2.72).

Conclusions: This study found a higher risk of leprosy associated with MCMVP that may reflect reverse causality. Our findings suggest the programme is, in fact, reaching the most vulnerable individuals, as intended in its objectives. Besides, the higher risk of leprosy among MCMVP beneficiaries even before receiving the benefit observed in sensitivity analysis may reflect residual confounding factors related.