This study aimed to determine the ability of a set of physical fitness tests to discriminate presence or absence of fibromyalgia in women.
The sample comprised 487 women with fibromyalgia (52.1 ± 8 yr) and 250 control women (49.3 ± 9 yr). We assessed physical fitness using the arm curl, 30-s chair stand, handgrip strength, 8-ft up and go, 6-min walk, chair sit and reach, and the back scratch tests. The revised fibromyalgia impact questionnaire was used to assess fibromyalgia severity and symptomatology.
Patients with fibromyalgia performed worse than control women in all the fitness tests studied (all, P < 0.001). The receiver operating characteristic analysis showed that all the fitness tests were able to discriminate between presence and absence of fibromyalgia (all, P < 0.001). The area under the curve ranged from 0.708 to 0.910 (all, P < 0.001). Among the fitness tests studied, the arm curl test, followed by the 30-s chair-stand and handgrip strength tests, showed the highest capacity discriminating between the presence and absence of fibromyalgia. An arm curl test score of <20 repetitions was associated with increased odds of having fibromyalgia (odds ratio (OR), 35.6; 95% confidence interval, 12.6-101) in women age 35-44 yr. An arm curl test score of <16 repetitions was associated with increased odds of having fibromyalgia (OR, 23.7; 95% confidence interval, 10.3-54.0) in women age 35-44 yr. In the group of women age 55-65 yr, the highest OR was observed for the handgrip strength test and the odds of having fibromyalgia was 17 times greater than that in patients who performed less than 19 kg.
The arm curl, 30-s chair stand, and handgrip strength tests powerfully discriminated women with fibromyalgia from healthy women. Identification of women who fail to meet the suggested standards can help to easily, quickly, and cheaply rule out the presence of the disease, especially in primary care settings.