In patients on suppressive antiretroviral therapy, greater CD8-cell activation and higher interleukin-6 level are associated with functional impairment.

In aging HIV-uninfected individuals, immune activation and inflammatory markers are associated with declines in physical function and increased frailty. Given evidence that, despite years of suppressive antiretroviral therapy (ART), HIV-infected patients have higher levels of T-cell activation and inflammation than HIV-uninfected individuals, investigators examined whether these markers are associated with functional impairment in HIV-infected patients.

Of 359 HIV-infected individuals aged 45 to 65 who were on suppressive ART for at least 6 months and completed functional testing, 140 (39%) were identified as having high function (i.e., the ability to complete a 400-meter walk and no deficits on a frailty phenotype score or on a physical performance battery) and 33 (9%) had low function (poor scores on these measures). The analysis involved 31 low-functioning patients and 49 matched high-functioning controls (median age, 51; median CD4 count, 551 cells/mm3; 95% with undetectable HIV RNA).

Low-functioning patients were more likely than high-functioning controls to be current smokers (48% vs. 20%). They also had a lower mean nadir CD4 count (110 vs. 178 cells/mm3), had more comorbidities (3.6 vs. 2.3), and were taking more non-ART medications (6.0 vs. 4.2). Greater CD8-cell activation and higher interleukin-6 level were each associated with greater odds of low function, even after adjustment for CD4-cell count, smoking, and viral hepatitis status. Other markers of immune activation and inflammation and measures of microbial translocation, immunosenescence, and leukocyte telomere length were not associated with low function.

CITATION(S):

Erlandson KM et al. Association of functional impairment with inflammation and immune activation in HIV type 1–infected adults receiving effective antiretroviral therapy. J Infect Dis 2013 May 6; [e-pub ahead of print].