Critically Appraised Topic
The patient who led us to pursue this question is: 53 y.o. female with a diagnosis of Rheumatoid Arthritis (RA) and considered in Functional Class II based on criteria from the American College of Rheumatology (ACR). Medical treatment to date has included a regimen of Humira (adalimumab), low-resistance strength training, and exercises to increase range of motion (ROM). Problems identified include: decreased strength, decreased functional range of motion, and decreased physical ability.
Is high-intensity strength training better than standard care of Rheumatoid Arthritis in improving muscular strength, health status, and physical ability?
Clinical Bottom Line
Based on the results of the outcomes from de Jong et al., Flint-Wagner et al., and Lemmey et al., there is moderate evidence to suggest that an intervention of high-intensity strength training for patients with RA is better than standard care of low-intensity ROM exercises in improving muscular strength and physical ability. However, there is sufficient evidence that this intervention does not improve health status. Outcomes of interest included muscle strength of the knee extensors measured by dynamometry, aerobic tests such as the 50-foot walk test and standardized bicycle ergometer test and health status evaluated by various forms of the Health Assessment Questionnaire. All three studies indicated significant increases in knee extensor muscle strength from the pretest to posttest; however, only de Jong et al. and Lemmey et al. reported significant differences when compared to the control group, (p<0.05). de Jong et al. found a mean change score of 26.1 ± 60.9 N in their intervention group compared to 9.6 ± 52 N in the control group while Lemmey et al. reported a large effect size of 0.34. According to our analyses, 0.34 is actually representative of a small effect size. Lemmey et al. did not describe why the effect size range was skewed in the article. Regarding improvement of aerobic tests, all three studies also indicated significant improvement in aerobic function. Mean change scores for the standardized bicycle ergometer test in the study de Jong et al. were 8.2 ± 37.1 W and 8.2 ± 37.1 W (p<0.05) for the intervention and control group, respectively. Statistical analyses for the 50-foot walk test in the study by Flint-Wagner et al. indicated a mean change score of -1.2 ± 1.6 seconds for the intervention group and 0.8 ± 1.0 seconds for the control group (p<0.05) with a large effect size of 1.34 based on a 95% confidence interval. Lastly, Lemmey et al. reported a large effect size of 0.28 using a 95% confidence interval for the 50-foot walk test. According to our analyses, 0.28 is actually representative of a small effect size. Lemmey et al. did not describe why the effect size range was skewed in the article. No significant changes were found between any intervention group or control group for all three studies concerning health status via health questionnaires. Overall, it is difficult to generalize the results of this study to our patient at hand. The results and interventions of this study can be applied to her based on the age range and RA functional classification level; however, our patient was not on the same drug regimen as patients in the study by Flint-Wagner et al. and all three interventions were conducted in group sessions over a period of 16 weeks to 2 years instead of one-on-one physical therapy sessions. We wanted to incorporate high-intensity strengthening exercises over a more realistic time frame of a typical physical therapy script with one-on-one interactions between the therapist and patient as well as providing a home exercise program. Further research should evaluate the effects of a short-term, six to eight week intervention of individualized, high-intensity strength training for the same outcome measures. Also, more research is needed on the effects of high-intensity strength training on radiographic joint damage for safety and to monitor disease progression. Perhaps results would also differ if patients were treated one-on-one instead of in a group setting. Thus future research should investigate this interaction.
Biggs, Meghan and Yap, Carrie, "The effect of high-intensity strength training as compared to standard medical care on muscle strength, physical function and health status, in patients with Rheumatoid Arthritis Functional Class II" (2014). PT Critically Appraised Topics. 44.