The impact of socioeconomic conditions on chronic Chagas disease progression

The extent to which a patient's socioeconomic conditions determine the persistence or control of chronic Chagas disease has not been previously investigated. The aim of this study was to evaluate the effect of socioeconomic conditions on clinical and serologic measures of disease progression.

Data on the following socioeconomic variables were obtained by questioning as part of medical history taking at admission: birth in a rural area, time of residence in endemic and urban areas (in years), overcrowding index (i.e. number of inhabitants/number of bedrooms), absence of toilet facilities, years of education, employed or unemployed, and health insurance coverage (i.e. private contributory medical insurance cover). The study endpoints for the Cox regression analysis were: consistently negative results on serologic tests and on tests for markers of cardiomyopathy progression by the end of the study.

The study included 801 Argentine patients (mean age 42 years) who were followed up for a mean of 10 years between 1990 and 2005. After adjustment for age and antiparasitic treatment, negative seroconversion was associated with a short time of residence in an endemic area (hazard ratio [HR]=0.97; 95% confidence interval [CI], 0.96-0.99; P=.004), a low overcrowding index (HR=0.82; 95% CI, 0.70-0.97; P=.022) and medical insurance cover (HR=1.46; 95% CI, 1.01-2.09; P=.04). After adjustment for age, sex, ECG abnormalities and antiparasitic treatment, a low rate of cardiomyopathy progression was associated with more years of education (HR=0.88; 95% CI, 0.80-0.97; P=.01) and higher medical insurance cover (HR=0.49; 95% CI, 0.30-0.81; P=.005).

Socioeconomic conditions had a significant effect on chronic Chagas disease progression which was independent of antiparasitic treatment and clinic characteristics.