Do antidepressant medications relieve chronic low back pain?

Journal of Family Practice, Dec, 1993 by Judith A. Turner, Mary C. Denny

A number of reviews of the literature pertaining to the effectiveness of antidepressants for various pain problems have been published, sometimes with conflicting conclusions.[8,14-16,18,28] For example, in the family practice literature, in the same year (1989), one article stated that "many antidepressant drugs . . . are known to be effective in treating . . . back pain,"[10] (p213) while another stated that "the role of antidepressants in back pain . . . is less clear."[29] (p234) A more recent article in the family practice literature states that "a large and consistent body of literature suggests that [tricyclic antidepressants] may have specific beneficial effects in . . . chronic low back pain."[3] (p24)

The reason for undertaking this literature synthesis was to update previous reviews with an extensive literature search and application of systematic, objective methods of data abstraction to articles identified as pertinent. The focus was on examining the literature to address basic questions of practical importance to primary care phusicians making decisions concerning optimal treatments for patients suffering low back pain. There is a great need for scientific information concerning outcomes of various treatments for low back problems in primary care settings, given the frequency of such problems and the fact that back pain is a more chronic recurrent condition than previously though.[30] Specifically, we wanted to determine the following for patients with chronic low back pain:

1. Whether antidepressant medications, as a group, are more effective than placebo in decreasing pain, disability, depression, and analgesic medication use

2. Whether the analgesic effects of antidepressant medications are independent of their antidepressant effects.

Methods

Article Selection

The MEDLINE (from 1966) and PsycLIT (from 1967) bibliographic databases through December 1992 were searched to identify relevant English-language journal articles. The search strategies used included the following terms: antidepressive agents, antidepressants, the names of specific antidepressant medicatiwns, and chronic pain, low back pain, and backache. Articles were also identified from bibliographies of articles and book chapters, and from inquiries to pharmaceutical companies and to several expert researchers in the field. By these methods 423 articles were identified, and their titles and abstracts (when available) were reviewed. Any articles that appeared to be possibly relevant to this literature synthesis were then retrieved and read. Studies were included Ef they reported data from placebo-controlled or drug comparison trials evaluating antidepressant medication in samples consisting exclusively of people with low back pain. Six articles met these criteria.[31-36]

Data Extraction

A standardized coding form was developed, and each article was read independently by two clinical psychologist clinician-researchers, who used the form to extract data on study methods, subject characteristics, antidepressants studied and their dosages, lengths of trials, measures, and results. Disagreements were discussed until a consensus was reached.