IS THE CLINICAL COURSE OF HIV-1 CHANGING - COHORT STUDY

Objective: To assess whether the clinical course of HIV infection has changed from 1985 to 1995. Design: Cohort study. Setting: Infectious d iseases clinic. Subjects: 285 patients recruited from September 1985 t o January 1995 with less than or equal to 12 months between the dates of their last seronegative and first seropositive test result and with first follow up visit in the six months after seroconversion and at l east 12 months' follow up. Patients were grouped according to the date of seroconversion. Main outcome measures: Time to CD4 cell count of < 500, 400, and 200 x 10(6) cells/l and clinical outcome defining AIDS; variation in cell count per day between consecutive visits, and ratio between this variation and time from estimated date of seroconversion at each visit. Results: The groups were similar in age, number with a cute primary HIV infection, CD4 cell count at intake, and cell count a t the beginning of antiretroviral treatment; they differed in sex rati o, risk factors for HIV,probability of CD4 cell decline to < 500, 400, and 200 x 10(6) cells/l, and risk of developing AIDS. Acute infection , seroconversion after December 1989, and serum beta 2 microglobulin > 296 nmol/l were independent predictors of poor clinical course. The s peed of CD4 cell decline, expressed as cell variation divided by the n umber of days between consecutive visits, increased with more recent s eroconversion (P = 0.02). Ratio between the speed of CD4 cell decline and time from estimated date of seroconversion at each visit was also higher in the patients who seroconverted after December 1989. Conclusi ons: The faster disease progression and the higher speed of CD4 cell d ecline at early stages in the patients with recently acquired HIV infe ction suggest changes in the clinical course of HIV infection.