心理的評価からみた慢性腰痛に対する抗うつ薬の有効性と問題点

The Therapeutic Effects and the Adverse Effects of an Anti-Depressant Drug in Patients with Chronic Low Back Pain were Evaluated from a Psychological Standpoint

　抄録：慢性腰痛（下肢痛を含む）を有する症例に対する抗うつ薬（トラゾドン）の有効性と投与上の問題点について心理的評価の面から検討した．対象は慢性腰痛を有する12例である．トラゾドン（25～50mg）服用前に，SDS（うつ病自己評価尺度）とBSPOP（整形外科患者に対する精神医学的問題評価のための簡易質問票）を用いて心理的評価を行い，投与後4週の時点で症状の変化と服用状況を調査した．その結果，投与前の評価で心理的影響が小さいと判定された症例では，トラゾドンは慢性腰痛を軽減させる効果を有していると判定できた．一方，投与前の評価で心理的影響が大きいと判定された症例では，トラゾドン投与による副作用が頻発した．心理的影響が大きい慢性腰痛患者は，抗うつ薬の副作用発現の可能性を説明することで，かえって軽微な体調の変化に敏感に反応してしまうと考えられる．抗うつ薬の処方時には，患者が安心して服用できる服薬指導が必要である．

　The therapeutic effects and the adverse effects of an antidepressant drug (trazodone) were evaluated from a psychological standpoint in twelve patients with chronic low back pain (including sciatica). SDS and BSPOP were used to perform for psychological assessment before treatment with trazodone (25mg or 50mg/day). Symptoms were prospectively monitored for 4 weeks. The results showed that trazodone improved chronic low back pain when the mental state was mild. However, trazodone never improved chronic low back pain when the mental state was severe, and cases of severe mental state were associated with a high incidence of adverse effects, i.e., nausea or sleep disturbances. Chronic low back pain patients with a severe mental state may have been overly sensitive to the slight changes in physical condition induced by trazodone. In conclusion, trazodone is indicated for chronic low back pain patients with mild mental states. Informed consent is necessary before prescribing antidepressants for chronic low back pain patients.