Background/Purpose : Loss of muscle and strength typically occur with advanced age. Chronic inflammatory diseases, such as rheumatoid arthritis, have reported similar deficits. Giant cell arteritis (GCA) is an inflammatory systemic vasculitis that occurs almost exclusively in the elderly. We sought to determine the body composition, strength, and functional disability in a cross-sectional sample of GCA patients (pts) and compare these parameters to age-matched community dwelling non-GCA controls.
Methods : Pts were recruited from a tertiary academic center. Body composition was evaluated by dual energy x-ray absorptiometry (DEXA, GE Lunar Prodigy Software V13); strength was assessed by hand grip dynamometry and lower extremity isokinetic testing (Biodex System 3 dynamometer); and functional disability by the short physical performance battery (SPPB). The SPPB includes: chair stands, semitandem, tandem, one-leg stand, and gait speed (6 meter walk). GCA pts were matched (1:2 ratio) by age (within 1 year), gender, and race to eligible controls randomly selected from the Baltimore Longitudinal Study of Aging (BLSA). The BLSA prospectively follows a cohort of healthy volunteers who undergo comprehensive evaluation every 1-2 years. Continuous and categorical variables were compared using student’s t-test and chi-square analyses respectively.
Results : GCA pts (N=18) had a mean ± SD age of 74 ± 7 yrs (range 59-86). They were mostly female (83%), white (83%) and had a positive temporal artery biopsy (89%). Mean disease duration was 2.7 ± 4.1 yrs (range 0.1-16); 7 (39%) were diagnosed >2 years prior to their study visit. Most (78%) were on daily prednisone (11 ± 13 mg/d) with a mean duration of steroid exposure at the study visit of 11 ± 13 months. GCA pts were significantly weaker on all measures of strength compared to BLSA controls (Table 1). GCA pts also had marked slowness as indicated by longer time to complete chair stands and slower gait speed. Body composition was similar between the two groups without a corresponding decrease in lean mass among the GCA group despite their decreased strength.
Conclusion : GCA pts in this small cross-sectional study were significantly weaker and slower than age-matched controls in the absence of significant differences in body composition. Slow gait speed (<0.8 m/s) is associated with disability, morbidity, and mortality among elderly adults. The preservation of lean mass in elderly GCA pts, in the presence of clinically significant weakness, suggests that impairment/dysfunction in muscle quality rather than muscle quantity may be the culprit. Prednisone use may be a significant contributor to weakness and slowness in elderly GCA pts. However, prednisone is unavoidable in the treatment of this potentially catastrophic illness and future investigation should focus on methods to improve strength and function in GCA pts regardless of their need for steroid therapy.
Table 1.
|
|
GCA N=18 |
BLSA N=36 |
p-value |
|
Age, mean ± SD (years) |
75 ± 7 |
74 ± 7 |
0.672
|
|
Gender (% women) |
83 |
78 |
0.633 |
|
|
|
|
|
|
Race (% Caucasian) |
83 |
83 |
1.000 |
|
|
|
|
|
|
Strength Measures |
|
|
|
|
Grip strength (kg) |
21 ± 6 |
27 ± 9 |
0.015 |
|
|
|
|
|
|
Leg extension 180d/s peak torque (Nm) |
|
|
|
|
Left quadriceps |
46 ± 17 |
89 ± 2 (n=23) |
<0.001 |
|
Right quadriceps |
49 ± 20 |
69 ± 16 (n=31) |
0.001 |
|
|
|
|
|
|
Leg flexion 180d/s peak torque (Nm) |
|
|
|
|
Left hamstrings |
21 ± 10 |
66 ± 22 (n=23) |
<0.001 |
|
Right hamstrings |
23 ± 10 |
49 ± 15 (n=31) |
<0.001 |
|
Functional Measures (Short Physical Performance Battery) |
|
|
|
|
Completes 10 chair stands (%) |
83 |
94 |
0.184 |
|
Time to complete (seconds) |
32 ± 8 |
23 ± 5 |
<0.001 |
|
|
|
|
|
|
Holds semi tandem stand 30 seconds (%) |
94 |
97 |
0.610 |
|
|
|
|
|
|
Holds tandem stand 30 seconds (%) |
83 |
83 |
0.149 |
|
|
|
|
|
|
Holds one leg stand 30 seconds (%) |
17 |
100 |
<0.001 |
|
|
|
|
|
|
Gait Speed (m/s) |
0.86 |
1.06 |
0.005 |
|
|
|
|
|
|
Body Composition by DEXA |
|
|
|
|
BMI (kg/m2) |
28 ± 6 |
25 ± 4 |
0.079 |
|
|
|
|
|
|
Bilateral arms |
|
|
|
|
Total fat mass (g) |
3177 ± 1155 |
2559 ± 989 |
0.046 |
|
Total lean mass (g) |
4262 ± 1070 |
4337 ± 1315 |
0.836 |
|
|
|
|
|
|
Bilateral legs |
|
|
|
|
Total fat mass (g) |
10334 ± 4352 |
8965 ± 3830 |
0.242 |
|
Total lean mass (g) |
13141 ± 2853 |
13600 ± 3242 |
0.538 |
|
|
|
|
|
|
Trunk |
|
|
|
|
Total fat mass (g) |
16360 ± 3834 |
13603 ± 5915 |
0.079 |
|
Total lean mass (g) |
19235 ± 2533 |
20889 ± 4311 |
0.140 |
|
|
|
|
|
|
Total Body |
|
|
|
|
Total fat mass (g) |
30915 ± 8614 |
25942 ± 9772 |
0.073 |
|
Total lean mass (g) |
39995 ± 6065 |
42216 ± 8898 |
0.346 |
|
|
|
|
|
Disclosure:
R. L. Manno,
None;
A. C. Gelber,
None;
P. Seo,
None;
S. M. Levine,
CE Outcomes,
5,
Up to Date,
7;
S. R. Ghazarian,
None;
P. H. Chen,
None;
K. J. Stewart,
None;
J. Metter,
None;
L. Ferrucci,
None;
K. R. Fontaine,
None.
ACR Meeting Abstracts - https://acrabstracts.org/abstract/body-composition-strength-and-function-in-elderly-patients-with-giant-cell-arteritis/