Pharmacological management of chronic low back pain in older patients: a randomized controlled trial of the effect of pregabalin and opioid administration

Pregabalin and opioids are used to treat chronic low back pain (LBP). No previous investigations have compared the efficacy of pregabalin and that of opioids for chronic LBP. We performed a randomized controlled trial of pregabalin and opioids in 65 consecutive patients aged 65 years or older who had chronic LBP. Each agent was administered randomly in different phases. Pain and activities of daily living (ADL) were evaluated after 4 weeks of treatment using the visual analog scale, Japanese Orthopaedic Association score, Roland Morris Disability Questionnaire, short-form McGill Pain Questionnaire, EuroQol quality-of-life scale, and geriatric depression scale. Neuropathic pain was evaluated using a neuropathic pain screening questionnaire. The effectiveness rate was 73.3 % for pregabalin and 83.3 % for opioid, showing no significant difference. The mean durations until the onset of effect were 10.2 and 6.1 days, respectively, albeit without significant difference. Pregabalin was effective for LBP with neuropathic pain, whereas opioids were effective for non-neuropathic pain. The improvement of ADL was greater with opioids than with pregabalin. Pregabalin was effective for LBP in patients with lower limb symptoms, whereas opioids were effective for those without lower limb symptoms. Aside from screening tests, consideration of neuropathic pain and lower extremity symptoms may be an integral component in the selection of the appropriate medication for chronic LBP. Moreover, the therapeutic objectives, including pain relief and/or improvement of ADL, should be specified.