The Relationship of Pain to Physical Function in Patients With HIV: An Underappreciated Phenomenon (SA517-B)

Abstract

1.Understand the importance of investigating pain in HIV-infected patients.2.Describe the impact of pain on physical function in HIV-infected patients. Pain, which commonly co-occurs with mood disorders and substance abuse, is associated with impaired physical function. In HIV-infected patients, physical function declines rapidly and is associated with increased mortality. We evaluated the association of pain, alone and in the context of mood disorders and substance abuse, with physical function in patients with HIV. We analyzed cross-sectional Patient Reported Outcome (PRO) data collected between 4/2008 & 6/2011. PROs included measures of three domains of physical function (mobility, usual activities, self-care) and pain (EuroQOL); mood (depression-PHQ-9, or anxiety-PHQ-A); and substance abuse (ASSIST). Univariate and multivariable logistic regression models were fit to evaluate impairment in each domain of physical function. We first analyzed the main effects of pain, mood, and substance abuse on physical function. We evaluated interactions between pain, mood, and substance abuse. Models were adjusted for age, race, sex, and insurance status. Among 1903 participants (median age 44, median CD4 count 445 cells/mm3, 33% uninsured, 58% virologically suppressed), 37% reported moderate-extreme pain. In adjusted analyses, pain was associated with impairment in all three domains of physical function (mobility 10.8 [95% CI7.8-15.0], self-care 4.2 [95% CI 2.3-7.6], and usual activities 5.6 [95% CI 4.2-7.6]). Mood was also associated with impairments in all domains of physical function (mobility 2.3 [95% CI1.7-3.1], self-care 4.1 [95% CI 2.4-6.9], and usual activities 6.1 [95% CI 4.5-8.1]), whereas substance abuse was only associated with impairment in self-care (2.2 [95% CI 1.3-3.8]). Interactions between pain, mood, and substance abuse were not significant. Pain was associated with up to 11 times the odds of impaired physical function in HIV-infected patients.