NATIONAL TRENDS IN THE CONCURRENCE OF TUBERCULOSIS AND ACQUIRED-IMMUNODEFICIENCY-SYNDROME

Background: Elucidation of the relationship between tuberculosis (TB) and the acquired immunodeficiency syndrome (AIDS) is needed to help pr edict the future course of these two epidemics. We examined nationwide trends in TB and AIDS occurring in the same individual. Methods: Heal th departments in the 50 states, District of Columbia, Puerto Rico, an d Guam matched their TB and AIDS case registries to determine the numb er of persons diagnosed with both TB and AIDS. The number of AIDS case s, TB cases, AIDS cases that matched with a TB case on the TB registry , and TB cases that matched with an AIDS case on the AIDS registry wer e reported to the Centers for Disease Control and Prevention, Atlanta, Ga. Data were analyzed for the period from 1981 through 1991. The num ber of matched TB-AIDS cases was compared with a modeled estimate of e xcess TB cases during the period from 1985 through 1990. Results: From 1981 through 1991 there were 11 299 AIDS cases that matched with a TB case on the TB registry, representing 5.1% (geographic variation, 0% to 9.3%) of AIDS cases. The TB cases that matched with an AIDS case on the AIDS registry represent 4.3% (geographic variation, 0% to 15.1%) of TB cases from 1981 through 1991. Since 1981, matched TB and AIDS ca ses increased yearly through 1990. When examined by year of AIDS repor t, the percentage of AIDS cases that matched with a TB case increased from 1981 to 1982 (1.9% to 5.1%), remained fairly constant from 1983 t hrough 1987 (range, 4.0% to 4.7%), increased in 1988 (5.4%) after extr apulmonary TB was added to the AIDS case definition, and increased sli ghtly through 1990 (5.8%). When examined by year of TB report, the per centage of TB cases that matched with an AIDS case increased steadily from 1981 through 1990 (0.1% to 9.5%). The calculated fraction of exce ss TB cases during the period from 1985 through 1990 that could be acc ounted for by identified TB-AIDS cases was 30%. Conclusion: The risk o f TB or AIDS among persons already diagnosed with one disease is much higher than among the general population. The percentage of persons wi th TB who are also diagnosed with AIDS has been increasing rapidly. Hu man immunodeficiency virus-induced immunosuppression is an important c ontributor to the TB epidemic and probably accounts for a minimum of 3 0% of excess TB cases during the period from 1985 through 1990.