Comparison of functional status instruments in HIV-infected adults on effective antiretroviral therapy

The best method for assessment of functional status in human immunodeficiency virus type 1 (HIV-1) infected persons is unknown.

We hypothesized that 3 instruments to assess frailty or disability in elderly populations would perform similarly in HIV-1-infected persons.

HIV-infected subjects 45 to 65 years old with plasma HIV-1 RNA <48 copies/mL were classified prospectively as low, moderate, or high function by Fried's frailty phenotype (FFP), the Short Physical Performance Battery (SPPB), and 400-m walk test. Functional instrument agreement was evaluated by weighted kappa statistic, and relationships with demographic or clinical factors were evaluated by odds ratios (OR).

There were 359 participants (85% male, mean age 52 years, mean CD4+ lymphocyte count 551 cells/µL) who were evaluated. Three percent to 8% were low, 31% to 51% were moderate, and 42% to 62% were high function. FFP, SPPB, and 400-m walk test had moderate agreement for functional classification (61%-64%; κ = 0.34-0.41). Across instruments, lower reported physical activity (OR ≯ 5.5; P ≤ .005), no current employment (OR ≯ 4.2; P < .02), arthritis (OR ≯ 6.5; P < .02), neurologic disease (OR ≯ 2.6; P < .05), debilitating pain (OR ≯ 5.4; P < .008), psychiatric disease (OR ≯3.1; P < .03), more comorbidities (OR ≯ 3.6; P ≤ .005), and more non-antiretroviral therapy medications (OR ≯ 3.5; P ≤ .01) were associated with lower function. Current CD4 <200 cells/µL was more likely among low-function (11%) than high-function (2%) persons on FFP (P = .04); other HIV-related characteristics were not significantly different (P > .05) between functional categories on any instrument.

Moderate functional impairment is common among middle-aged HIV-infected persons, with similar frequencies of impairment detected by 3 instruments. Reduction in comorbid disease, increased physical activity, and improved pain symptom management could reduce functional impairment among persons aging with HIV-infection.