A mixed model for factors predictive of pain in AIDS patients with herpes zoster

A unifying model of herpes zoster pain presents considerable analytical cha llenges es due to the requirement for prospective, data collection and the varying rates of pain resolution reported by individual;patients. Demograph ic, clinical, and quality-of-life measures were collected on 166 human immu nodeficiency virus (HIV)-infected patients enrolled In a randomized control led trial of antiviral therapy of herpes tester comparing acyclovir with so rivudine. A "mixed, model" was used to assess factors predictive of pain se verity activity impairment, and sleep interruption. The average rate of cha nge in acute pain tons - 0.04 unit pain pet day for the first month. Chroni c pain decreased - 0.12 per month for months 1-12. Acute pain severity was positively correlated with number of new shin vesicles, analgesic use, and baseline pain, and negatively related to percentage of lesion healing and c rusting. Postherpetic neuralgia,was correlated with baseline pain, pain at I month, and duration of lesions. Treatment group, gender race, and CD4 cou nt were not related to change in pain sa,severity. These analyses verify th e significance of baseline pain as a significant predictor of pain resoluti on and average pain severity as a predictor of return to normal daily activ ities and sleep. The severity of acute pain at presentation and at I,month are significant predictors of chronic pain. (C) U.S. Cancer Pain Relief Com mittee, 1999.