Effects of smoking status on immediate treatment outcomes of multidisciplinary pain rehabilitation.

OBJECTIVE: The primary aim of this study was to determine the effects of smoking on treatment outcomes following multidisciplinary pain rehabilitation. A secondary aim was to assess the tobacco use characteristics of smokers with chronic pain.
DESIGN: A prospective, nonrandomized, repeated measures design.
SETTING: Multidisciplinary pain rehabilitation center at a tertiary referral medical center. PATIENTS: All patients (N = 193) consecutively admitted from August 2005 through February 2006.
INTERVENTIONS: A 3-week outpatient multidisciplinary pain rehabilitation program. OUTCOME MEASURES: The Multidimensional Pain Inventory (MPI), Short Form-36 Health Status Questionnaire (SF-36), Center for Epidemiologic Studies-Depression scale (CES-D), Pain Anxiety Symptom Scale (PASS-20) and Pain Catastrophizing Scale (PCS) were administered at admission and dismissal.
RESULTS: The study involved 49 (83% women) smokers and 144 (83% women) nonsmokers. The mean number of cigarettes smoked daily was 17.5 (SD 11.1) and the mean duration of smoking was 21.5 years (SD 12.1). After adjusting for demographic differences, repeated measures of analysis of covariance showed a main effect of smoking status for MPI affective distress (P = 0.008), CES-D (P = 0.001) and PCS (P = 0.011). An interaction of smoking status and time was found for the PASS-20 (P = 0.028), MPI affective distress (P = 0.033), MPI life control (P = 0.003) and SF-36 role-emotional (P = 0.004) subscale. While the majority of smokers were ready to consider smoking abstinence, 43% declined a brief smoking cessation intervention.
CONCLUSIONS: In this series of patients undergoing multidisciplinary treatment for chronic pain, immediate treatment effects for a variety of outcome measures were similar or significantly better in smokers compared with nonsmokers.