The Hong Kong Institute of Education, Hong Kong, China; The Third Affiliated Hospital of Guangzhou Medical University, Guangzhou, China Tung Wah College, Hong Kong, China.
Pain Physician. 2013 Nov-Dec;16(6):E685-704.
Low back pain (LBP) is one of the most common health problems in adults. The impact of LBP on the individual can cause loss of health status in the form of symptoms and loss of function related to pain in the back; limitation of daily, leisure, and/or strenuous activities, and disability. LBP also poses an economic burden to society, mainly in terms of one of the most common reasons for seeking medical care (direct treatment costs), and accounts for the large number of work days lost (indirect costs). To reduce the impact of LBP on adults, drug therapy is the most frequently recommended intervention. Over the last decade, a substantial number of randomized clinical trials of drug therapy for LBP have been published.
To determine the effectiveness of drug therapy for the treatment of chronic nonspecific low back pain (CNLBP).
Systematic review
A systematic review and meta-analysis of randomized controlled trials was conducted. Five databases (Medline, CINAHL, Science Direct, CAJ Full-text Database, and Cochrane databases) were searched for articles published from 2002 to 2012. The eligibility criteria were randomized trials and double-blind controlled trials of oral or injection drug therapy for CNLBP in subjects who were aged at least 18 years old, published in English or Chinese. Two independent reviewers extracted the data.
A total of 25 drug therapy trials were included. cyclo-oxygenase-2 (COX-2) nonsteroidal anti-inflammatory drugs (NSAIDs), tramadol, and opioids were commonly used. Only 5 trials studied the efficacy of adjuvant analgesics of antiepileptics (n = 1) and antidepressants (n = 4) for CNLBP. The standardized mean difference (SMD) for COX-2 NSAIDs in pain relief was -12.03 (95% confidence interval [CI]: -15.00 to -9.06). The SMD for tramadol in pain relief was -1.72 (95% CI: -3.45 to 0.01). As the 95% CI crossed 0, this effect size was not considered statistically significant. The SMD for the overall effects of opioids in pain relief was -5.18 (95% CI: -8.30 to -2.05). The SMD for the partial opioid agonist drug in pain relief was -7.46 (95% CI: -11.87 to -3.04).
The follow-up periods of these included trials in the meta-analysis ranged from 4 to 24 weeks. The difference of follow-up periods influenced how study outcomes were recorded. These included trials also had significant differences in patient selections. Some trials may actually include CNLBP patients with neuropathic pain, as not having focal neurological findings or signs does not mean that the pain is not neuropathic. Consequently, different pain conditions may influence patients who responded to the same drug and then influence pooled estimates of treatment effect size.
This review endorses the use of COX-2 NSAIDs as the first-line drugs for CNLBP. Tramadol shows no statistically significant effect on pain relief, but has small effect sizes in improving functioning. Among included opioid therapy studies, the overall effects of opioids and the partial opioids agonist drug had statistically significant treatment effects in pain relief for CNLBP patients.
下腰痛（LBP）是成年人中最常见的健康问题之一。LBP 对个体的影响会导致健康状况下降，表现为背部疼痛相关的症状和功能丧失；日常活动、休闲活动和/或剧烈活动受限以及残疾。LBP 也会给社会带来经济负担，主要是因为它是最常见的求医原因之一（直接治疗费用），并导致大量工作日的损失（间接成本）。为了减少 LBP 对成年人的影响，药物治疗是最常推荐的干预措施。在过去的十年中，已经发表了大量关于 LBP 药物治疗的随机临床试验。
确定药物治疗慢性非特异性下腰痛（CNLBP）的有效性。
系统评价
对随机对照试验进行系统评价和荟萃分析。从 2002 年至 2012 年，检索了 5 个数据库（Medline、CINAHL、Science Direct、CAJ 全文数据库和 Cochrane 数据库）中的文章。纳入标准为口服或注射药物治疗 CNLBP 的随机试验和双盲对照试验，研究对象为年龄至少 18 岁，发表在英文或中文的文献。两名独立的审稿人提取数据。
共纳入 25 项药物治疗试验。环氧化酶-2（COX-2）非甾体抗炎药（NSAIDs）、曲马多和阿片类药物是常用的药物。只有 5 项试验研究了辅助镇痛剂抗癫痫药（n=1）和抗抑郁药（n=4）对 CNLBP 的疗效。COX-2 NSAIDs 缓解疼痛的标准化均数差（SMD）为-12.03（95%置信区间[CI]：-15.00 至-9.06）。曲马多缓解疼痛的 SMD 为-1.72（95%CI：-3.45 至 0.01）。由于 95%CI 跨越 0，因此该效应大小不被认为具有统计学意义。阿片类药物缓解疼痛的总体效果的 SMD 为-5.18（95%CI：-8.30 至-2.05）。阿片类部分激动剂缓解疼痛的 SMD 为-7.46（95%CI：-11.87 至-3.04）。
这些纳入荟萃分析的试验的随访期从 4 周到 24 周不等。随访期的差异影响了研究结果的记录方式。这些试验还存在患者选择的显著差异。一些试验实际上可能包括患有神经病理性疼痛的 CNLBP 患者，因为没有局灶性神经学发现或体征并不意味着疼痛不是神经病理性的。因此，不同的疼痛状况可能会影响对同一药物有反应的患者，然后影响治疗效果大小的汇总估计值。
本综述支持将 COX-2 NSAIDs 作为 CNLBP 的一线药物。曲马多在缓解疼痛方面没有统计学上的显著效果，但在改善功能方面有较小的效果。在纳入的阿片类药物治疗研究中，阿片类药物和阿片类部分激动剂的总体疗效在缓解 CNLBP 患者的疼痛方面具有统计学意义。
