February 23, 2011
Several studies (SMART, DART, TRIVICAN) have already cautioned against interrupting HIV treatment with time off drugs. This year, in the online journal AIDS, the Swiss HIV Cohort Study reported their review of 2,491 people that they followed an average of 7 years on HIV treatment.
Individuals were assigned in one of three groups: 1) 1,271 people who had one or more interruptions of treatment, 2) 469 people continually on treatment but with occasional viral loads above 1,000, and 3) 751 people continually on treatment with viral loads below 1,000.
In group 1, their CD4s increased on average to 427 cells, while 63.0% reached above 350 and 37.2% above 500 CD4s. In group 2, CD4s increased on average to 525 cells, while 76.3% reached >350 and 55.8% >500 CD4s. In group 3, CD4s increased on average to 645 cells, while 87.3% reached >350 and 68.0% >500 CD4s.
People who were on continuous treatment experienced higher CD4 counts, a lower rate of opportunistic complications and longer lifespan. Conversely, those who interrupted treatment faced more frequent OIs as well as an increased risk of death. These risks increased significantly in those whose total time off treatment lasted more than 6 months.