Handgrip Strength as a Reflection of General Muscle Strength in Chronic Obstructive Pulmonary Disease

Abstract

Muscle dysfunction is one of the main features in individuals with chronic obstructive pulmonary disease (COPD). Handgrip strength (HS) has been used as a representation of general muscle strength in various populations, and a few studies found correlation between HS and other measures of upper and lower limbs’ muscle strength in the general population, although this was not yet studied in depth in COPD. The aims of this study were to verify if HS is cross-sectionally well correlated with upper and lower limbs’ muscle strength in individuals with COPD, and to identify a new cutoff for handgrip weakness in this population. HS was assessed by a dynamometer, whereas other muscle strength assessments comprised maximal voluntary contraction (MVC) of the quadriceps femoris and 1-repetition maximum (1RM) of biceps and triceps brachii, pectoralis major, latissimus dorsi and quadriceps femoris. Additional assessments included pulmonary function and volumes, body composition and exercise capacity. Fifty individuals with COPD were studied (65 ± 7 years; FEV₁ 51 ± 14%pred). HS showed moderate-to-strong correlations with all 1-RM assessments (0.62<r < 0.75) and especially with MVC of the quadriceps femoris (r = 0.83) (p < 0.05 for all). Correlations were stronger for male than female individuals, and the assessment performed on right, left or dominant hand did not present significant differences. A cutoff of 0.3892 for HS/weight yielded an AUC = 0.90 to identify weakness. In conclusion, HS is a good reflection of upper and lower limbs’ muscle strength in individuals with COPD. Its usefulness as a surrogate for more complex assessments must be based on the settings and conditions.

Keywords:

• Pulmonary disease
• chronic obstructive
• muscle strength
• hand strength
• quadriceps muscle
• muscle weakness

Acknowledgments

The authors would like to thank the colleagues from the Laboratory of Research in Respiratory Physiotherapy of UEL for their support.

Author contributions

JF and FP had full access to all of the data and take responsibility as guarantors for the integrity of the data and the accuracy of the analysis and conclusions. JF, FVCM, LCS and KCF made substantial contributions to the conception or design of the work. All authors contributed substantially to the acquisition, analysis or interpretation of data for the work. Further, all authors also contributed by critically revising the article and providing the final approval of the version to be submitted.

Declaration of interest

The authors report no conflicts of interest in this work.

Ethical approval

The study protocol was approved by the Institutional Committee of Ethics in Research (no. 1.730.247).