Diabetes increases the risk of recent-transmission tuberculosis in household contacts in São Paulo, Brazil.

SETTING

A cohort of household contacts of tuberculosis (TB) index cases from four public health clinics in São Paulo, Brazil.

OBJECTIVE

To measure the association between diabetes mellitus (DM) among household contacts and recent-transmission TB (RT TB).

DESIGN

Index TB cases (n = 263) identified from 2001 to 2002 in São Paulo, whose household contacts (n = 1383) were monitored for active TB until December 2010.

RESULTS

From 2001 to 2010, there were 29 cases of RT TB among household contacts (cumulative incidence 2.1%, 95%CI 1.4-2.9). DM in household contacts was associated with RT TB (OR 3.96, 95%CI 1.33-11.79) even after adjustment for human immunodeficiency virus (HIV) status, smoking and alcohol use (adjusted OR [aOR] 3.21, 95%CI 1.01-10.19). HIV infection was also associated with RT TB (OR 6.40, 95%CI 1.40-29.40; aOR 4.81, 95%CI 0.96-24.18). Household contact DM was not associated with non-RT TB (OR 1.27, 95%CI 0.30-5.40). The time to diagnosis of TB was shorter in household contacts with and without DM (P = 0.035) and in household contacts with and without HIV (P = 0.0002).

CONCLUSION

Household contact DM was associated with an increased risk of RT TB in a cohort in Brazil, lending support to the active screening of household contacts with DM for TB in Brazil.