Dataset Information

Skeletal Muscle Fat and Its Association With Physical Function in Rheumatoid Arthritis.

ABSTRACT:

Objective

To characterize skeletal muscle fat (SMF), intermuscular adipose tissue (IMAT), and subcutaneous adipose tissue (SAT) in individuals with rheumatoid arthritis (RA), and assess the associations between these fat depots and physical function and physical activity.

Methods

In a cross-sectional analysis from an RA cohort, SMF, IMAT, and SAT were measured using computed tomography imaging of the midthigh cross-sectional region. Physical function was measured using the Health Assessment Questionnaire (HAQ) and a battery of performance-based tests that included quadriceps muscle strength, gait speed, repeated chair-stands, stair ascent, and single-leg stance. Physical activity was assessed using an activity monitor. Associations between SMF, IMAT, and SAT and physical function and activity were assessed by multiple linear regression models adjusted for potential confounders such as age, sex, body mass index (BMI), muscle area, and muscle strength.

Results

Sixty subjects with RA (82% female, mean ± SD age 59 ± 10 years, mean ± SD BMI 31.79 ± 7.16 kg/m² ) were included. In the adjusted models, lower SMF was associated with greater gait speed, single-leg stance, quadriceps strength, and physical activity, and less disability (R² ? range 0.06-0.25; P < 0.05), whereas IMAT was not associated with physical function or physical activity and SAT was negatively associated with disability (HAQ) (R² ? = 0.13; P < 0.05) and weakly but positively associated with muscle strength (R² ? = 0.023; P < 0.05).

Conclusion

Fat infiltration within the muscle seems to independently contribute to low physical function and physical activity, contrary to IMAT or SAT accumulation. Longitudinal studies are necessary to confirm the impact of SMF on disability and health promotion in persons with RA.

SUBMITTER: Khoja SS

PROVIDER: S-EPMC5677587 | biostudies-literature | 2018 Mar

REPOSITORIES: biostudies-literature

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Publications

Skeletal Muscle Fat and Its Association With Physical Function in Rheumatoid Arthritis.

Khoja Samannaaz S SS Moore Charity G CG Goodpaster Bret H BH Delitto Anthony A Piva Sara R SR

Arthritis care & research 20180206 3

<h4>Objective</h4>To characterize skeletal muscle fat (SMF), intermuscular adipose tissue (IMAT), and subcutaneous adipose tissue (SAT) in individuals with rheumatoid arthritis (RA), and assess the associations between these fat depots and physical function and physical activity.<h4>Methods</h4>In a cross-sectional analysis from an RA cohort, SMF, IMAT, and SAT were measured using computed tomography imaging of the midthigh cross-sectional region. Physical function was measured using the Health ...[more]

PMID: 28482146

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Dataset Information

Skeletal Muscle Fat and Its Association With Physical Function in Rheumatoid Arthritis.

Objective

Methods

Results

Conclusion

Publications

Skeletal Muscle Fat and Its Association With Physical Function in Rheumatoid Arthritis.

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