Small study shows Non-steroidal anti-inflammatory drugs do not mitigate the pain of endometriosis

I just saw this on endochick‘s blog and wanted to repost it here:

Nonsteroidal anti-inflammatory drugs for pain in women with endometriosis
Allen C, Hopewell S, Prentice A, Gregory D

Summary
Endometriosis is a common gynaecological condition that affects women. It can lead to painful symptoms, including painful periods, pain during or after sexual intercourse, pelvic and lower abdominal pain, and infertility. It can greatly affect women’s quality of life by impacting on their careers, everyday activities, sexual and non-sexual relationships, and fertility. Non-steroidal anti-inflammatory drugs (NSAIDs) are the most commonly used first-line treatment for endometriosis because they have few side-effects and many are available over the counter. This review found limited evidence on whether NSAIDs (naproxen) are effective for the treatment of pain caused by endometriosis. There is inconclusive evidence to show whether or not any individual NSAID is more effective than another. As shown in other Cochrane reviews, women using NSAIDs need to be aware that NSAIDs may cause adverse effects such as nausea, vomiting, headache, and drowsiness. This review is limited as it only included one study which involved 20 women.

This is a Cochrane review abstract and plain language summary, prepared and maintained by The Cochrane Collaboration, currently published in The Cochrane Database of Systematic Reviews 2009 Issue 3, Copyright © 2009 The Cochrane Collaboration. Published by John Wiley and Sons, Ltd.. The full text of the review is available in The Cochrane Library (ISSN 1464-780X).
This record should be cited as: Allen C, Hopewell S, Prentice A, Gregory D. Nonsteroidal anti-inflammatory drugs for pain in women with endometriosis. Cochrane Database of Systematic Reviews 2008, Issue 2. Art. No.: CD004753. DOI: 10.1002/14651858.CD004753.pub3

This version first published online: October 19. 2005
Last assessed as up-to-date: April 23. 2008

Abstract

Background

Endometriosis is a common gynaecological condition that affects women and can lead to painful symptoms and infertility. It greatly affects women’s quality of life, impacting on their careers, everyday activities, sexual and non-sexual relationships, and fertility. Non-steroidal anti-inflammatory drugs (NSAIDs) are the most commonly used first-line treatment for endometriosis.
Objectives

To assess the effects of NSAIDs used for the management of pain in women with endometriosis compared to placebo, other NSAIDs, other pain management drugs, or no treatment.

Search strategy

We searched the Cochrane Menstrual Disorders and Subfertility Group Trials Register (April 2008) published in the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library), MEDLINE (1966 to April 2008), EMBASE (1980 to April 2008), and the reference lists from relevant publications. Experts in the field were also contacted for information about possible studies.

Selection criteria

We included all randomized controlled trials (RCTs) describing the use of NSAIDs in the treatment of endometriosis in women of all ages.

Data collection and analysis

Two review authors (CA and SH) independently read and extracted data from each of the included studies. Crossover trials were analysed using the inverse variance method in RevMan to calculate the odds ratio for binary outcomes.

Main results

Two trials were identified but only one trial, with 24 women, was included in the analysis. Comparing NSAIDs (naproxen) to placebo, there was no evidence of a positive effect on pain relief (odds ratio (OR) 3.27, 95% CI 0.61 to 17.69) in women with endometriosis. There was also inconclusive evidence to indicate whether women taking NSAIDs (naproxen) were less likely to require additional analgesia (OR 0.12, 95% CI 0.01 to 1.29) or to experience side effects (OR 0.46, 95% CI 0.09 to 2.47) when compared to placebo.

Authors’ conclusions

There is inconclusive evidence to show whether or not NSAIDs (naproxen) are effective in managing pain caused by endometriosis. There is no evidence on whether any individual NSAID is more effective than another. As shown in other Cochrane reviews, women using NSAIDs need to be aware of the possibility that these drugs may cause unintended effects.