Background: Tuberculosis (TB) is a major cause of death in HIV patients worldwide. Here we describe the epidemiology and outcome of HIV-TB co-infections in a high-income country with low TB incidence and integrated HIV and TB therapy according to European guidelines.
Methods: This study was based on the HIV cohort of the Helsinki University Hospital which includes all HIV patients in the Helsinki region with a population of 1.5 million. Totally, 1939 HIV-positives who have been under follow-up between 1998 and 2015 were included.
Results: TB was diagnosed in 53 (2.7%) of the HIV-patients. The TB incidence rate was higher in injecting drug users (IRR 3.15; 95% CI 1.33-7.52) and heterosexuals (IRR 3.46; 95% CI 1.64-7.29) compared to men having sex with men. The incidence rate was also higher in those born in Sub-Saharan Africa (IRR 3.53; 95% CI 1.78-7.03) compared to those born in Finland. There was a significant reduction in the total TB incidence rate of 59% per 6-year period between 1998 and 2015 (p < 0.001). In injecting drug users there was a reduction in incidence rate from 1182 to 88 per 100,000 (p < 0.001) and in people born in Sub-Saharan Africa from 2017 to 195 per 100,000 (p < 0.001). Among the 53 HIV-TB co-infected cases, one female and 15 males died during follow up. HIV was the primary cause of death in five patients but none of the deaths were caused by TB.
Conclusion: The incidence rate of tuberculosis among HIV-positives in Finland has been declining between 1998 and 2015. Among injecting drug users, the reduction is probably explained by harm reduction interventions and care in comprehensive care centers in Helsinki. The increased coverage of antiretroviral therapy is probably another main reason for the decline in TB incidence rates. Despite good treatment results for both HIV and TB, the all-cause mortality among Finnish males with HIV-TB was high, and common causes of death were intoxications and suicides.
Keywords: Co-infection; Epidemiology; HIV; Outcome; Tuberculosis.