Exercise and global well-being in community-dwelling adults with fibromyalgia: a systematic review with meta-analysis

Abstract

Background: Exercise has been recommended for improving global-well being in adults with fibromyalgia. However, no meta-analysis has determined the effects of exercise on global well-being using a single instrument and when analyzed separately according to intention-to-treat and per-protocol analyses. The purpose of this study was to fill that gap.

Methods: Studies were derived from six electronic sources, cross-referencing from retrieved studies and expert review. Dual selection of randomized controlled exercise training studies published between January 1, 1980 and January 1, 2008 and in which global well-being was assessed using the Fibromyalgia Impact Questionnaire (FIQ) were included. Dual abstraction of data for study, subject and exercise program characteristics as well as assessment of changes in global well-being using the total score from the FIQ was conducted. Risk of bias was assessed using the Cochrane bias assessment tool. Random-effects models and Hedge's standardized effect size (g) were used to pool results according to per-protocol and intention-to-treat analyses.

Results: Of 1,025 studies screened, 7 representing 5 per-protocol and 5 intention-to-treat outcomes in 473 (280 exercise, 193 control) primarily female (99%) participants 18-73 years of age were included. Small, statistically significant improvements in global well-being were observed for per-protocol (g and 95% confidence interval, -0.39, -0.69 to -0.08) and intention-to-treat (-0.34, -0.53 to -0.14) analyses. No statistically significant within-group heterogeneity was found (per-protocol, Qw = 6.04, p = 0.20, I2 = 33.8%; intention-to-treat, Qw = 3.19, p = 0.53, I2 = 0%) and no between-group differences for per-protocol and intention-to-treat outcomes were observed (Qb = 0.07, p = 0.80). Changes were equivalent to improvements of 8.2% for per-protocol analyses and 7.3% for intention-to-treat analyses.

Conclusions: The results of this study suggest that exercise improves global well-being in community-dwelling women with fibromyalgia. However, additional research on this topic is needed, including research in men as well as optimal exercise programs for improving global well-being in adults.

Figure 1

Flow diagram for the selection of studies. ^aThe number of reasons for exclusion exceeds the number of studies excluded because some studies were excluded for multiple reasons.

Figure 2

Forest plot for changes in global-well being. Forest plot for point estimate standardized effect size changes (Hedge's g) in global well-being derived from the total score on the FIQ and analyzed according to per-protocol analyses and intention-to-treat analyses. The black squares represent the standardized mean difference (Hedge's g) while the left and right extremes of the squares represent the corresponding 95% confidence intervals. The middle of each of the two black diamond's represents the overall standardized mean difference (Hedge's g) for each type of analysis (per-protocol and intention-to-treat) while the left and right extremes of the diamonds represent the corresponding 95% confidence intervals.

Figure 3

Forest plot for changes in global-well being with each study deleted once. Point estimate standardized effect size changes (Hedge's g) in global well-being derived from the total score on the FIQ and analyzed according to per-protocol and intention-to-treat and analyses with each study deleted from the model once. The black squares represent the standardized mean difference (Hedge's g) while the left and right extremes of the squares represent the corresponding 95% confidence intervals. The middle of each of the two black diamond's represents the overall standardized mean difference (Hedge's g) for each type of analysis (per-protocol and intention-to-treat) while the left and right extremes of the diamonds represent the corresponding 95% confidence intervals.

Figure 4

Cumulative meta-analysis for changes in global well-being. Cumulative meta-analysis ranked by year, for point estimate standardized effect size changes (Hedge's g) in global well-being derived from the total score on the FIQ and analyzed according to per-protocol and intention-to-treat and analyses. The black squares represent the standardized mean difference (Hedge's g) while the left and right extremes of the squares represent the corresponding 95% confidence intervals. The middle of each of the two black diamond's represents the overall standardized mean difference (Hedge's g) for each type of analysis (per-protocol and intention-to-treat) while the left and right extremes of the diamonds represent the corresponding 95% confidence intervals. Studies are added one at a time according to date of publication and the results summarized as each new study is added.