Characteristics of studies
| Study | Participants | Intervention | Outcomes |
|---|---|---|---|
| Atkinson et al.26 | 108 participants with chronic (≥ 6 mo) LBP with or without radiating leg pain. Mean age ± SD: gabapentin group 57.6 ± 8.8 yr; placebo group 54.6 ± 11.4 yr. | Flexible dosing of gabapentin up to 3600 mg/d for 12 wk, v. matching placebo. Add-on therapy with NSAIDs permitted. | Pain, disability and adverse events at wk 1–5, 7, 9 and 12. |
| Baron et al.27 | 217 participants with chronic (≥ 3 mo) radiculopathy. Mean age ± SD: pregabalin group 52.5 ± 11.1 yr; placebo group 52.6 ± 12.8 yr. | Five-phase intervention of screening, single-blind placebo, single-blind pregabalin, double-blind, then tapering. Placebo responders and pregabalin nonresponders removed before double-blind phase. In the randomized double-blind phase, pregabalin dose was the individual optimal dose determined in single-blind phase (maximum 600 mg/d), for 6 wk v. matching placebo. Add-on therapy not allowed. | Pain, disability and adverse events at wk 1–6, 8, 10 and 11. |
| Khoromi et al.28* | 42 participants with chronic (≥ 3 mo) sciatica. Median age 53 (range 28–74) yr. | Flexible dosing up to 400 mg/d of topiramate for 6 wk v. active placebo (flexible dosing of diphenhydramine up to 50 mg/d) for 8 wk. | Pain, disability and adverse events at end of crossover periods (wk 10 and 18). |
| Markman et al.29* | 29 participants with chronic (> 3 mo) lumbar spinal stenosis with neurogenic claudication. Mean age ± SD: pregabalin/placebo group 71.1 ± 7.9 yr, placebo/pregabalin 69.0 ± 8.7 yr. | Flexible dosing of pregabalin up to 300 mg/d or diphenhydramine of 25 mg/d for 13 d. Seven-day washout between crossover periods. Other analgesic (other than gabapentin) permitted if stable at baseline. | Pain, disability and adverse events at 15-second increments during exercise and at d 4, 5, 11, 13 and 14. |
| Mathieson et al.30 | 207 participants with acute (7 d to < 3 mo) or chronic (≥ 3 mo) sciatica. Mean age ± SD: pregabalin group 52.4 ± 17.2 yr; placebo group 55.2 ± 16.0 yr. | Flexible dosing of pregabalin up to 600 mg/d for ≤ 8 wk, v. matching placebo. Add-on analgesic therapy permitted. | Pain, disability and adverse events at wk 2, 4, 8, 12, 26 and 52. |
| McCleane31* | 30 participants with chronic (> 3 mo) LBP. Mean age ± SD: cohort mean 42.4 ± 14.6 yr. | Flexible dosing of gabapentin titrated in 300 mg increments weekly to maximum 15 mg/kg/d for 6 wk v. placebo. Seven-day washout between crossover periods. Add-on therapy with NSAIDs or paracetamol plus codeine combination permitted. | Pain and adverse events at wk 1 to 6 of both crossover periods. |
| McCleane32 | 80 participants with chronic LBP with or without radiating leg pain (neuropathic pain features e.g., paresthesia, excluded). Mean age ± SD: gabapentin group 41.3 ± 13.1 yr; placebo group 47.8 ± 11.7 yr. | Fixed titration of gabapentin up to 1200 mg/d over 6 wk v. placebo, after 2-wk baseline washout. Add-on analgesia permitted. | Pain and adverse events at wk 8. |
| Muehlbacher et al.33 | 96 participants with chronic (≥ 6 mo) LBP with or without radiating leg pain (excluding neurologic deficits). Mean age ± SD: topiramate group 48.8 ± 5.5 yr; placebo group 48.7 ± 5.0 yr. | Fixed titration of topiramate, titrated from 50 mg/wk to 300 mg/d by wk 6 then remained for 4 wk, v. placebo. Add-on therapy not permitted. | Pain, disability and adverse events at wk 1 to 10. |
| Yildirim et al.34 | 50 participants with chronic (≥ 3 mo) sciatica. Mean age ± SD: gabapentin group 38.0 ± 7.4 yr; placebo group 40.5 ± 10.5 yr. | Flexible dosing of gabapentin from 900 mg/day to up to 3600 mg/day for 8 wk, versus placebo. Add-on therapy not permitted. | Pain and adverse events at wk 4 and 8. |
Note: LBP = low back pain, NSAIDs = nonsteroidal anti-inflammatory drugs, SD = standard deviation.
↵* Crossover trial.