Objectives: To determine the ability of handgrip strength test to discriminate between presence and absence of fibromyalgia (FM) and FM severity in women.
Design: A case-control study.
Setting: Granada, south Spain.
Participants: Women with FM (mean age ± SD, n=81; 50.0±7y) and healthy women (mean age ± SD, n=44; 47.7±6y).
Interventions: Not applicable.
Main Outcome Measures: Handgrip strength was measured in both hands (average score was used in the analyses) by a maximal isometric test using a hand dynamometer.
Patients were classed as having moderate FM if the score in the Fibromyalgia Impact Questionnaire (FIQ) was less than 70 and as having severe FM if the FIQ was 70 or greater.
Results: Handgrip strength levels were lower in patients with FM than healthy women (19.3 vs 27.9kg; P<.001) and in women with severe FM (FIQ?70) compared with those with moderate FM (FIQ<70) (16.9 vs 20.2kg; P=.02).
Receiver operating characteristic curve analyses revealed that:
• The handgrip strength threshold that best discriminated between the presence and absence of FM was 23.1kg [50.9 lbs] (area under the curve [AUC]=.88; 95% confidence interval [CI], 0.82-0.94; P<.001),
• Whereas the handgrip strength threshold that best discriminated between severe and moderate FM was 16.9kg [37.2 lbs] (AUC=.67; 95% CI, 0.53-0.80; P<.05).
Logistic regression analysis showed that:
• Handgrip strength 23.1kg or less was associated with 33.8 times higher odds (95% CI, 9.4-121.5) for having FM after adjustment for age.
• In the FM group, handgrip strength 16.9kg or less was associated with 5.3 times higher odds (95% CI, 1.9-14.5) for having severe FM.
Conclusions: Handgrip strength is reduced in women with FM as well as those with severe FM from their peers with moderate FM.
Identification of women who fail to meet the suggested standards can be a helpful and informative tool for clinician.
Source: Archives of Physical Medicine and Rehabilitation, Jan 2011;92(1):83-8. PMID: 21187209, by Aparicio VA, Ortega FB, Heredia JM, Carbonell-Baeza A, Sjöström M, Delgado-Fernandez M. Department of Physical Education and Sport, School of Sports Sciences, University of Granada, Granada, Spain; Department of Biosciences and Nutrition, Unit for Preventive Nutrition, NOVUM, Karolinska Institutet, Huddinge, Sweden. [Email: firstname.lastname@example.org]