BACKGROUND: Epidemiologic data suggest that zidovudine (ZDV) could pre
vent the AIDS dementia complex (ADC), but this hypothesis has not been
specifically studied. PATIENTS AND METHODS: We have reviewed the medi
cal records of all patients with human immunodeficiency virus (HIV) in
fection admitted to our section between January 1990 and December 1993
who were diagnosed with ADC, and we have compared them to those of a
control group with regard to the interruption of ZDV at least 3 months
before. Controls were selected from the remaining HIV-related admissi
ons, matched by calendar year, CD4-cell count and previous HIV-disease
stage. RESULTS: Thirty-nine cases and 39 controls were available for
analysis; twenty-nine (74%) and 25 (64%) were male. The median age was
similar for both groups: 30. Thirty-one patients (79%) in each group
had a previous diagnosis of AIDS, six (15%) in each group had an AIDS-
related complex and in two (5%) the ADC was the first complication of
their HIV disease. The median CD4-cell counts were 79.6 and 79.4 x 10(
6)/l.. Twenty-three patients in each group had taken ZDV. Six of these
from the ADC group had withdrawn treatment, as compared to 2 from the
control group (odds ratio [OR] 3.36; 95% confidence interval [CI]: 0.
54-35.76). On the other hand, 16 patients with ADC were still on ZDV a
t the time of diagnosis, as compared to 21 controls (OR: 0.66; 95% CI:
0.22-1.60). CONCLUSION: In this case-control study, the interruption
of treatment with ZDV was not found to be a risk factor for the develo
pement of ADC.