The spread of AIDS and the re-emergence of tuberculosis in Catalonia, Spain

Abstract

Objective: To assess the impact of HIV/AIDS on the incidence of tuberculosis (TB) and to analyse the determinants of TB presenting as the first indicative disease of AIDS.

Design: Analysis of TB and AIDS surveillance data.

Setting: Catalonia, north-east Spain.

Patients: Two separate sources were used: (i) TB cases reported to the Catalan TB registry diagnosed between January 1982 and December 1993; (ii) AIDS cases reported to the AIDS Catalan registry diagnosed between January 1982 and December 1994.

Main outcome measures: Expected and observed TB cases, and number and characteristics of AIDS cases presenting with TB.

Results: From 1987 to 1993 the annual TB crude incidence rate increased by 50% to a rate of 49.7 per 100,000, with a least 60% of the increase directly due to AIDS. During that period specific rates among children aged 0-4 years remained high at around 40 per 100,000. A total of 7,010 AIDS cases were diagnosed between 1988 and 1994, of whom 24.3% had TB. Multivariate analysis from those AIDS cases showed that besides male sex, young age, and urban residence, the strongest predictors of TB among AIDS cases were history of imprisonment (odds ratio, 2.16; P < 0.001) and intravenous drug use (odds ratio, 1.65; P < 0.001).

Conclusions: The high rates of TB among children and young adults suggest that TB transmission has increased during this period, especially among people at high risk of AIDS. The determinants of individual risk of TB among AIDS patients act together, especially in prisons. The HIV/TB coepidemic is an emerging threat potentially for all and requires expanding targeted measures to prevent and control both disease in our setting.