Lam R W, Levitan R D, Tam E M, Yatham L N, Lamoureux S, Zis A P
Department of Psychiatry, University of British Columbia, Vancouver.
Can J Psychiatry. 1997 Apr;42(3):303-6. doi: 10.1177/070674379704200309.
Up to one-third of patients with seasonal affective disorder (SAD) do not have a full response to light therapy. Given the evidence for serotonergic dysregulation in SAD, we examined the possible role of l-tryptophan as an augmentation strategy for nonresponders and partial responders to light therapy.
Eligible drug-free patients meeting DSM-IV criteria for SAD were treated for 2 weeks using a standard morning light therapy regimen (10,000 lux cool-white fluorescent light for 30 minutes). Partial and nonresponders were treated for 2 weeks with open-label l-tryptophan (1 g 3 times daily) while light therapy was continued. Ratings at baseline and follow-up included the 29-item Structured Interview Guide for the Hamilton Depression Rating Scale, SAD version (SIGH-SAD) and the Clinical Global Impression (CGI) scale.
Sixteen patients began the l-tryptophan augmentation phase. Two patients discontinued medications within 3 days because of side effects. In the 14 patients completing treatment, the addition of l-tryptophan resulted in significant reduction of mean depression scores. Nine of 14 patients (64%) showed very good clinical responses to combined treatment and minimal side effects.
This open-label study suggests that l-tryptophan may be an effective augmentation strategy for those patients with SAD who show limited or poor response to bright ligh therapy. Further placebo-controlled studies are warranted to demonstrate efficacy.
高达三分之一的季节性情感障碍（SAD）患者对光疗法没有完全反应。鉴于SAD中血清素调节异常的证据，我们研究了L-色氨酸作为光疗法无反应者和部分反应者增强策略的可能作用。
符合DSM-IV标准的SAD无药物治疗的合格患者采用标准的早晨光疗法方案（10000勒克斯冷白色荧光灯照射30分钟）治疗2周。部分反应者和无反应者在继续进行光疗的同时，采用开放标签的L-色氨酸（每日3次，每次1克）治疗2周。基线和随访时的评分包括汉密尔顿抑郁量表29项结构化访谈指南SAD版（SIGH-SAD）和临床总体印象（CGI）量表。
16名患者开始L-色氨酸增强治疗阶段。2名患者因副作用在3天内停药。在完成治疗的14名患者中，添加L-色氨酸导致平均抑郁评分显著降低。14名患者中有9名（64%）对联合治疗表现出非常好的临床反应且副作用最小。
这项开放标签研究表明，L-色氨酸可能是对强光疗法反应有限或不佳的SAD患者的一种有效增强策略。需要进一步进行安慰剂对照研究以证明其疗效。
