EPIDEMIOLOGY OF CRYPTOSPORIDIOSIS AMONG EUROPEAN AIDS PATIENTS

Objective: To study epidemiology and possible risk factors associated with the development of cryptosporidiosis among European patients with AIDS. Methods: An inception cohort of 6548 patients with AIDS, consec utively diagnosed from 1979 to 1989, from 52 centres in 17 European co untries was studied. Data on all AIDS defining events were collected r etrospectively from patients' clinical records. Kaplan-Meier estimates , log rank tests and Cox proportional hazard models were used to exami ne for possible risk factors associated with cryptosporidiosis. Result s: Cryptosporidiosis was diagnosed in 432 (6.6%) patients, 216 at time of the AIDS diagnosis and 216 during follow-up. The probability of be ing diagnosed with cryptosporidiosis at AIDS diagnosis was significant ly lower for intravenous drug users (1.3%) than for homosexual men (4. 1%) and for patients belonging to other transmission categories (4.0%) (p < 0.001). The probability was also higher for patients from Centra l Europe compared with patients from South Europe (4.1% versus 2.5%, p = 0.005). The rate of developing cryptosporidiosis after the diagnosi s of AIDS was 3 per 100 patient years of follow-up. The rate was signi ficantly lower for intravenous drug users than for homosexual men (rel ative risk 0.34, 95% confidence limits 0.22-0.54) and for women compar ed with men (RR 0.43 (0.21-0.87)). The risk was higher in North Europe than in South and Central Europe. In a multivariate analysis only tra nsmission category remained a significant predictor for the developmen t of cryptosporidiosis. Conclusion: The development of cryptosporidios is in AIDS patients may be associated with sexual risk behaviour.