Such treatment improved CD4 counts in Scottish patients

EDITOR—Egger et al describe the positive impact of antiretroviral combination treatment of people with HIV infection in Switzerland.1 We analysed data from Scotland's national CD4 lymphocyte monitoring scheme to describe the effect of antiretroviral combination therapies on progression of HIV disease among infected people in Scotland.2

We divided people undergoing monitoring of CD4 counts over two consecutive years in 1993-7 into four cohorts. Altogether 770 patients underwent CD4 cell count monitoring during 1993 and 1994, 731 during 1994 and 1995, 706 during 1995 and 1996, and 708 during 1996 and 1997. Median differences in CD4 cell counts were calculated by comparing the patients' first CD4 cell counts in years one and two. In each cohort the median first CD4 cell count in year one (baseline) was similar, ranging between 247 and 290 × 10⁶ cells/l. For each of the three cohorts spanning 1993-6, the median loss of CD4 lymphocytes over consecutive years ranged between 24 and 32. For the 1996-7 cohort, however, there was a median gain of six CD4 cells (95% confidence interval 0 to 12) (figure).