CROI: Interrupting HIV Treatment Raises Cardio Risk

LOS ANGELES, Feb. 27 -- Interrupting antiretroviral therapy for HIV patients increases the risk of cardiovascular disease by more than 50% over four years, a British researcher said here.

The counterintuitive finding comes from the aborted SMART study, which was evaluating continued therapy versus interruptions when CD4 counts were sufficiently high, Andrew Phillips, Ph.D., of the Royal Free Hospital in London told an oral abstract session at the Conference on Retroviruses and Opportunistic Infections.

The 5,472-patient study was halted in January 2006, when it became clear that there was an excess of opportunistic infections in the treatment interruption arm, noted Dr. Phillips (HIV Drug Holidays Not a SMART Idea).

Because antiretroviral drugs are known to have effects on lipid metabolism that appear to increase the risk of cardiovascular disease, the study also tracked the effect of treatment interruption on cardiovascular disease, he said.

But an "exploratory analysis" of data from the trial showed a consistent excess of cardiovascular events -- including death, non-fatal myocardial infarction, and non-fatal stroke -- beginning within months of the start of the study.

When the study was stopped, Dr. Phillips said, the overall hazard ratio between the arms was 1.57 in favor of the sustained treatment arm, with a 95% confidence interval from 1.00 to 2.46.

The increased risk was "marginally significant" at P

But, she added, "the overall message is that treating HIV is better than not treating it."