Khan JS, et al. - Researchers sought to determine the longitudinal effect of smoking on patients attending a tertiary pain management center. Using the Collaborative Health Outcomes Information Registry of patients attending the Stanford Pain Management Center from 2013 to 2017, they assessed 12,368 patients who completed the Collaborative Health Outcomes Information Registry questionnaire. Of these, 8,584 patients had complete data for propensity analysis, which was done to ascertain the independent effects of smoking on patients with chronic pain. Significantly worse pain intensities, pain interference, pain behaviors, physical functioning, fatigue, sleep-related impairment, sleep disturbance, anger, emotional support, depression, and anxiety symptoms were reported for smokers at time of pain consultation vs nonsmokers. In mixed-model analysis, smokers vs nonsmokers tended to have worse pain interference, fatigue, sleep-related impairment, anger, emotional support, and depression over time. Compared with patients with chronic pain who were nonsmokers, those who smoke reported worse pain, functional, sleep, and psychological and mood outcomes. In addition, the prognostic importance of smoking was noted for poor recovery and improvement over time.