Both fibromyalgia and rheumatoid arthritis (RA) patients self-report similar disability. These diseases are viewed differently by the medical profession - as one has ample evidence of tissue damage and inflammation and the other does not.
We were interested to see if an objective measure produced similar results.
Twelve patients with RA were matched with 12 fibromyalgia patients by sex, age, and Health Assessment Questionnaire (HAQ) score.
The 24-hour ambulatory activity of these patients was recorded using the Numact monitor. [Note:
The Numact activity monitor consists of two sensors attached to a data logger. It gives a measure of the number and vigor of steps taken (total ambulatory energy expenditure)]. Statistical analysis was performed using independent group t test for the ambulatory activity data and Spearman's correlation coefficients for HAQ and total energy.
• There were no significant differences found between the two groups in terms of total activity.
• Other compared analyses for activity included the number of steps taken, vigor of steps, and time spent standing, which were not statistically different. The correlation coefficients of HAQ and total ambulatory activity for the fibromyalgia group were rho = -0.638 (p = 0.026).
• Patients with RA and fibromyalgia displaying similar levels of self-reported disability have objective evidence of similar levels of total ambulatory activity.
• There is a statistically significant correlation between self-reported and objective measurements of disability for the fibromyalgia patients.
• Either of these measures merits further study as outcome measures for fibromyalgia.
Source: Clinical Rheumatology, Feb 20, 2009. [E-pub ahead of print] PMID: 19229584, Raftery G, Bridges M, Heslop P, Walker DJ. City Hospitals Sunderland NHS Foundation Trust, Sunderland, UK. [E-mail: firstname.lastname@example.org]