HAART Reduces the Risk of Non-Hodgkin’s Lymphoma by Half
By
Liz Highleyman
Studies
have produced conflicting data about the frequency of various malignancies
among HIV positive people - including the AIDS-defining
cancer non-Hodgkin's lymphoma (NHL) -- and how prevalence and incidence have changed
since the introduction of effective antiretroviral therapy.
In
the January 11, 2008 issue of AIDS, investigators reported data from a
study assessing the long-term effect of HAART on the incidence of NHL among participants
in the Swiss HIV Cohort.
Between
1984 and 2006, the researchers followed 12,959 people with HIV, for a total of
75,222 person-years (PY) of observation; 36,787of these years were spent on HAART.
During this period, a total of 429 NHL cases were identified. Age- and sex-standardized
incidence was calculated, and Cox regression was used to estimate hazard ratios
(HR).
Results
•
NHL incidence reached 13.6 per 1000 PY in 1993-1995,
then fell to 1.8 per 1000 PY in 2002-2006.
•
Use of HAART was associated with a significant
decline in NHL incidence (HR 0.26; 95% CI 0.20-0.33).
•
The decline was even greater for primary brain
lymphomas than other types of NHL, falling from 32% to 13% of all NHL cases.
•
Among patients not on HAART, the following factors
were significant predictors of NHL incidence:
-
Being a man who has sex with men;
- Age 35 years or older;
- Lower CD4 cell
count at study enrollment.
•
Among
HAART users, only age was significantly associated with NHL risk.
•
In the HAART group, NHL incidence declined regardless
of pre-treatment CD4 cell count.
•
Nearly one-quarter of NHL cases in the HAART
group occurred among patients who had interrupted or discontinued treatment.
•
The risk of NHL incidence declined steeply in
the first several months after HAART initiation (HR 0.46; 95% CI 0.27-0.77).
•
The incidence was 0.12 (95% CI 0.05-0.25) 7 to10
years after starting HAART.
Conclusion
"HAART
greatly reduced the incidence of NHL in people with HIV, and the influence of
CD4 cell count on NHL risk," the researchers concluded. "The beneficial
effect remained strong up to 10 years after HAART initiation."
01/25/08
Reference
J
Polesel, GM Clifford, M Rickenbach, and others (for the Swiss HIV Cohort Study).
Non-Hodgkin lymphoma incidence in the Swiss HIV Cohort Study before and after
highly active antiretroviral therapy. AIDS 22(2): 301-306. January 11,
2008.
