Fatores individuais, da habitação e da atenção à saúde relacionados à incidência e desfechos de tratamento da hanseníase Salvador – Ba.

Abstract

Background: Despite great progress towards global elimination, leprosy remains a public health challenge in middle- and low-income countries. Current evidence suggests that, in these countries, home contacts of leprosy patients are at high risk for developing leprosy. Timely treatment is essential to stop transmission, but socioeconomic vulnerability factors can influence adherence and completion of leprosy treatment. In addition, research shows that components of inadequate housing are associated with a higher burden of leprosy. However, there is no evidence of an association between a social housing program and leprosy; which justifies deepening the theme. Overall objective: To study the risk factors for incidence and adherence to leprosy treatment, and the effect of a social housing program for low-income people on its detection. Specific objectives: i) To estimate the rates of detection of new cases of leprosy among household contacts of patients previously diagnosed with leprosy and investigate its associated factors; ii) to investigate MDT treatment completion in primary and specialized care units and its association with sociodemographic, geographic, and clinical characteristics; iii) To estimate the chances of leprosy detection among individuals who became MCMV recipients compared with their counterparts who did not benefit from the MCMV programme. Methods: The thesis was presented in 3 papers according to each specific objective. For the first objective, we used leprosy notification data collected between 2007-2014 and linked in the 100 Million Brazilian Cohort to investigate leprosy new case detection rates (NCDR) among household contacts of previously diagnosed leprosy patients and within sub-populations (e.g., by age, urbanicity, region, and community leprosy burden). Multilevel logistic regressions of mixed effects were used, with random effects specific to the state and family; For the second objective, we evaluated all new leprosy cases registered in Brazil (2006-2017), linked to data from the patient's diagnostic health unit with information from the National Registry of Health Facilities (CNES). Bivariate and multivariate analysis were performed using logistic regression models. All analysis were stratified according to the level of health care, such as primary care and specialized and hospital units; For the third objective, we conducted a case-control study nested in the Cohort of 100 Million Brazilians (2010-2015). Cases were selected from individuals in this cohort who were detected as a new case of leprosy. Controls were selected randomly based on a sampling of risk sets and according to correspondence variables (2:1). We use conditional logistic regression to estimate the association. Results for the first objective: Among 42,725 household contacts of 17,876 primary cases, the NCDR of leprosy was 636.3/100,000 pyr overall and 521.9/100,000 pyr in contacts <15 years. Household contacts of multibacillary cases had higher odds of becoming subsequent cases (ORadj 1.48, 95%CI 1.17-1.88), and the odds increased among contacts aged ≥50 years (ORadj 3.11, 95%CI 2.03-4.76). Leprosy detection was negatively associated with illiterate/preschool education level (ORadj 0.59, 95%CI 0.38-0.92). For children, the odds were increased among males (ORadj 1.70, 95%CI 1.20-2.42). Results for the second objective: Among 218,646 new leprosy cases diagnosed in Brazil between 2006-2017, 196,562 (89.9%) completed the MDT regimen. For those treated in primary health care, the lowest chances of completing treatment were associated with ages between 15-29 years (ORadj 0.57; 95% CI 0.52-0.61), blacks (ORadj 0.86; 95% CI 0.81-0.91), indigenous/Asian race/ethnicity (ORadj 0.85; 95% CI 0.74-0.97) and primary school education or less (ORadj 0.81; 95% CI 0.78-0.87). Multibacillary leprosy with ≤10 lesions (ORadj 0.92; 95% CI 0.88-0.96) and grade 1 or 2 physical disabilities (ORadj 0.91; 95% CI 0.88-0.95 e ORadj 0.86; 95% CI 0.81-0.93, respectively) reduced the chances of completing treatment. Living in urban areas (ORadj 1.12; 95% CI 1.08-1.17) and in the Southeast/South (ORadj 1.17; 95% CI 1.10-1.24) or Midwest (ORadj 1.13; 95% IC 1.07-1.19) regions increased the chances of completing treatment. In the Northeast, the chances of completing treatment were reduced (ORadj 0.86; 95% CI 0.82-0.90). Both specialized and hospital care had similar point estimates. Results for the third objective: The cohort study population (2010-2015) included 25,259,564 individuals, of which 621,068 (2.5%) were MCMV recipients. In this period, were diagnosed 9,036 new leprosy patients and was estimated a new case detection rate (NCDR) in 11.70/100,000 person-years (pyr) (95%CI 11.46-11.94). The NCDR were higher among MCMV recipients (13.27/100,000 pyr; 95%CI 11.41-15.43) compared to MCMV non-recipients (11.59/100,000 pyr; 95%CI 11.35-11.84). We found that the chances of become a leprosy case was 26% higher among individuals exposed to MCMV receipt (OR 1.25, 95%CI 1.01 to 1.53, p <0.038) compared to those non-exposed to MCMV programme. Conclusions: The results of this study highlight the urgent need for public health interventions, such as screening contacts, which specifically target this exclusively vulnerable population. In addition, it was possible to observe that actions to control leprosy are still not carried out uniformly throughout Brazil. Therefore, an integrated approach based on actions of early diagnosis, monitoring, assessment of deficiencies and strengthening of leprosy management in primary care is necessary, for the control of leprosy in accordance with the Global Leprosy Strategies. Finally, our results showed a greater chance of detecting leprosy among beneficiaries of social housing, which demonstrates that the time of exposure to new housing may not have been enough to overcome the social and health problems faced by these poor families. and extremely poor. It is noteworthy that social policies such as the MCMV must be improved and extended to the greatest possible number of needy families, as social development is a fundamental priority to reduce the incidence and burden of leprosy among low-income people. Future research should study the effect of the MCMV social housing program on leprosy and explore whether the results of this work will hold for a longer period.