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Abstract

  1. Top of page
  2. Abstract
  3. PATIENTS AND METHODS
  4. RESULTS
  5. DISCUSSION
  6. REFERENCES

Objective

To evaluate the impact of a 2-year program of strength training on muscle strength, bone mineral density (BMD), physical function, joint damage, and disease activity in patients with recent-onset (<2 years) rheumatoid arthritis (RA).

Methods

In this prospective trial, 70 RA patients were randomly assigned to perform either strength training (all major muscle groups of the lower and upper extremities and trunk, with loads of 50–70% of repetition maximum) or range of motion exercises (without resistance) twice a week; all were encouraged to engage in recreational activities 2–3 times a week. All patients completed training diaries (evaluated bimonthly) and were examined at 6-month intervals. All were treated with medications to achieve disease remission. Maximum strength of the knee extensors, trunk flexors and extensors, and grip strength was measured with dynamometers. BMD was measured at the femoral neck and lumbar spine by dual x-ray densitometry. Disease activity was determined by the Disease Activity Score, the extent of joint damage by the Larsen score, and functional capacity by the Health Assessment Questionnaire (HAQ); walking speed was also measured.

Results

Sixty-two patients (31 per group) completed the study. Strength training compliance averaged 1.4–1.5 times/week. The maximum strength of all muscle groups examined increased significantly (19–59%) in the strength-training group, with statistically significant improvements in clinical disease activity parameters, HAQ scores, and walking speed. While muscle strength, disease activity parameters, and physical function also improved significantly in the control group, the changes were not as great as those in the strength-training group. BMD in the femoral neck and spine increased by a mean ± SD of 0.51 ± 1.64% and by 1.17 ± 5.34%, respectively, in the strength-training group, but decreased by 0.70 ± 2.25% and 0.91 ± 4.07% in the controls. Femoral neck BMD in the 17 patients with high initial disease activity (and subsequent use of oral glucocorticoids) remained constantly at a statistically significantly lower level than that in the other 45 patients.

Conclusion

Regular dynamic strength training combined with endurance-type physical activities improves muscle strength and physical function, but not BMD, in patients with early RA, without detrimental effects on disease activity.

Persistent synovitis with joint swelling and limited joint mobility in rheumatoid arthritis (RA) patients may result in the stretching of tendons, ligaments, and joint capsules, with subsequent joint instability and decreases in muscle mass and strength. Furthermore, joint effusions directly inhibit contraction of the surrounding muscle groups, and if a muscle contracts while the joint is malaligned, it will not be able to generate its peak contractile force. Moreover, the compromises in biomechanical integrity of the joint and its surrounding tissues result in pain, altered loading response, and patterns of motion that are often energy insufficient and further limit the patient's physical activities (1).

With regard to osseous tissues, the disease duration (2–5), physical inactivity, impaired function (5–7), and the inflammatory process itself contribute to bone loss in diseases such as RA. The concomitant use of corticosteroids further enhances the development of both muscle atrophy and decrease in bone mineral density (BMD) (1, 8, 9). The vicious circle that results in losses of muscle strength, BMD, and functional capacity in RA is finally catalyzed by the generalized fatigue that is associated with inflammation, resulting in further limitations in physical activity.

Thus, the loss of muscle strength and functional capacity (6, 10–12) as well as the accelerated bone loss (13) may develop early in the course of RA. Various clinical trials examining the effects of exercise training programs on BMD in healthy subjects have been described (14). Some studies show that exercise does not lead to maintenance or improvement in BMD (15, 16), while others report positive results (17–19). The earlier studies indicate that the important osteogenic exercise stimulus is high strain rates and high peak forces in versatile movements. Moreover, the number of loading cycles probably increases in significance if the repetitive loading magnitude is low on the loaded side (20). Exercise is reportedly an important tool for reducing pain, stiffness, and joint tenderness in RA patients (21–23). Nevertheless, although physical activity is also of central importance in maintaining or increasing muscle strength in patients with RA, long-term studies regarding the effects of strength training on muscle performance (24, 25) and BMD (23, 24) are few. There is a definite need for additional longitudinal studies to determine the adaptation of the muscles and bones to various types of exercise training in patients with RA.

Therefore, the purpose of the present study was to investigate whether the 24-month strength training program used to increase muscle strength and physical function in patients with early RA also produces positive effects on BMD in these patients.

PATIENTS AND METHODS

  1. Top of page
  2. Abstract
  3. PATIENTS AND METHODS
  4. RESULTS
  5. DISCUSSION
  6. REFERENCES

Subjects

Seventy patients with recent-onset RA according to the 1987 criteria of the American College of Rheumatology (formerly, the American Rheumatism Association) (26) volunteered to participate in the 24-month study. Patients had been referred to the rheumatology unit at Jyväskylä Central Hospital for diagnosis and therapy. None of the patients had taken glucocorticoids or disease-modifying antirheumatic drugs (DMARDs) previously. The patients were randomly assigned to either the dynamic strength–training group or the control group. The randomization was carried out using clusters of 4 patients who had been stratified according to age (<50 years and ≥50 years) and sex to ensure that the demographic data of the study groups remained comparable.

This study was approved by the local ethics committee, and the participants gave their written informed consent.

Training programs

The patients in the dynamic strength–training group were personally instructed to perform a strength-training program for 24 months. The training program included exercises for the upper and lower extremities, using elastic bands for resistance, as well as abdominal and back muscle exercises, using dumbbells. The exercises for extremities were performed in a sitting or a standing position and the trunk exercises in a supine position. Subjects were instructed to exercise twice a week, with moderate loads (50–70% of the repetition maximum), 2 sets per exercise, and 8–12 repetitions per set. The exercise duration was ∼45 minutes. The intensity of the strength training was reevaluated every 6 months. In addition, the patients were encouraged to engage in recreational physical activities, such as walking, cycling, skiing, and swimming for an average of 2–3 times a week for 30–45 minutes each time.

The patients in the control group were instructed to perform range of motion and stretching exercises twice a week, without using additional resistance, to maintain their joint mobility. They were free to continue their recreational physical activities with the exception of strength training of any kind.

All subjects completed training diaries during the entire 2 years of followup. Diaries were mailed to the investigators every second month for evaluation.

Measurements

Muscle strength. The maximum unilateral concentric strength of the knee extensors was measured using the David 200 dynamometer (Outokumpu, Finland) (27). The subject was seated with the hips in a fixed position and the knee in 110° of flexion. The ankle was supported just above the malleoli. The load in the weight stack of the machine was gradually increased until the subject was unable to perform a full knee extension (starting from knee flexion of 110° to full extension) in order to record the subject's 1 repetition maximum (in kg). Maximum isometric forces of the trunk flexors and extensors were measured by an isometric strain-gauge dynamometer (28). With the subject in a standing position and the hips fixed at the level of the anterior superior iliac spine, a 5-cm–wide strap was tightened around the shoulders at the level of the clavicle during trunk flexion and at the level of the spina scapulae during trunk extension.

Isometric grip strength was measured by a Digitest dynamometer (Oulu, Finland) (29). The results of dynamic knee extension and isometric grip strength tests are expressed as the sum of the right and left side. Before the leg and trunk strength tests, the subjects warmed up with a bicycle ergometer and, thereafter, performed a few submaximal contractions on the strength dynamometer to become familiar with the testing procedure. In all strength measurements, the subjects received verbal encouragement to exert maximum force. The highest value obtained for 3–4 trials was used for the final analysis.

Bone mineral density

BMD was measured at the Rheumatism Foundation Hospital (Heinola, Finland) using dual x-ray absorptiometry bone densitometry (Lunar DPX; Lunar Corporation, Madison, WI) in duplicate measurements at months 0, 12, and 24. The measurement sites were lumbar vertebrae L2–L4 and the left proximal femur. Quality assurance tests for densitometry were run daily. The precision of the method was previously tested on adults, and the coefficient of variation was calculated to be 1.0% for the spine and 1.8% for the femoral neck.

Functional capacity

Functional capacity was assessed by patient self-report, using the Health Assessment Questionnaire (HAQ) (30). Maximum walking speed (in meters/second) over a distance of 30 meters was measured. The time used for initial acceleration was included in the calculation.

Clinical health status

The modified Disease Activity Score (DAS), including 28 tender and 28 swollen joints (DAS28), the patient's assessment of general health (on a 0–100-mm visual analog scale [VAS]) and the erythrocyte sedimentation rate were used to evaluate clinical disease activity (31). Pain, as assessed with a 1–100-mm VAS, and morning stiffness (minutes) were also evaluated.

Joint radiology

Radiographic damage in the peripheral small joints was scored according to the method described by Larsen et al (32, 33). The score ranged from 0 to 100, and included the 10 metacarpophalangeal joints, 8 metatarsophalangeal joints (second to fifth), and both wrists (all scored 0–5).

Statistical analysis

Means and standard deviations are given as descriptive statistics. Changes in muscle strength, BMD, and disease activity at the end of the training are expressed as percentages of the baseline values. Statistical comparisons between the study groups were performed with the unpaired t-test. The effects of strength training were analyzed by multivariate analysis of variance with repeated measures. Multiple linear regression analyses were used to explore the relationship between BMD and the demographic and disease-related risk factors.

RESULTS

  1. Top of page
  2. Abstract
  3. PATIENTS AND METHODS
  4. RESULTS
  5. DISCUSSION
  6. REFERENCES

Two patients from the strength-training group and 3 from the control group dropped out of the study after the baseline measurements (2 discontinued the exercises, 1 fell ill with cancer, 1 drowned, and 1 was involved in an accident and had neurologic symptoms). One patient from the strength-training group (whose data are included for the first year) dropped out of the study after the first year because of a lack of motivation for the training. The diagnosis changed for 3 patients (spondylarthrosis, psoriatic arthritis, and longstanding RA), and their data were excluded from the analysis. At baseline, there were no significant differences in demographic, strength, or clinical variables between the patients who completed the trial and those who dropped out.

At baseline, the study groups were comparable with regard to demographic variables (Table 1). After the initial measurements, therapy with DMARDs was instituted. All patients were initially treated with sulfasalazine, except for 1 patient in each group, who received gold sodium thiomalate because of allergies to sulfonamides. During the 24-month trial, the initial DMARD was changed in 15 and 19 patients in the strength-training group and the control group, respectively, because of inefficacy and/or adverse events.

Table 1. Baseline characteristics of the rheumatoid arthritis patients, by exercise group*
VariableStrength-training group (n = 31)Control group (n = 31)
No. of males:no. of females13:1811:20
Age, mean ± SD years49 ± 1049 ± 11
Weight, mean ± SD kg74 ± 1472 ± 11
Height, mean ± SD cm169 ± 8167 ± 9
Duration of symptoms, mean ± SD months10 ± 108 ± 12
No. of current smokers82
No. consuming 1–5 alcoholic drinks/week810
No. of postmenopausal women813
Time since menopause, mean ± SD years8.4 ± 3.67.6 ± 5.6

During the last 12 months of the study, 2 patients in the strength-training group and 10 in the control group were also treated for short periods with low-dose prednisolone (2.5–7.5 mg/day).

If the BMD measurements revealed osteopenia, treatment with alendronate (10 mg/day) was instituted. Thus, 3 patients in the strength-training group and 9 in the control group received bisphosphonate therapy for a mean ± SD of 6.2 ± 4.8 months and 8.3 ± 3.9 months, respectively.

The reported compliance with the exercise program averaged 1.5 times/week during the first 12 months and 1.4 times/week during months 13–24 in the strength-training group instead of the planned 2 times/week. The mean ± SD time used for various types of physical exercises during the first year were 240 ± 124 minutes/week for the strength-training group (including the strength-training exercise program) and 205 ± 103 minutes/week for the control group. During the second year, the corresponding values were 249 ± 121 and 187 ± 107 minutes/week. Three male patients in the strength-training group started to exercise in the gym instead of at home with the elastic bands.

Both groups had moderate disease activity at baseline, before initiation of DMARDs (Table 2). During the followup period, the parameters of disease activity improved statistically significantly in both groups. However, a significant between-group difference in favor of the strength-training group was observed.

Table 2. Parameters of disease activity and joint destruction in rheumatoid arthritis patients at baseline and after 6, 12, 18, and 24 months, by exercise group*
ParameterStrength-training group (n = 31)Control group (n = 31)Difference between groups (95% CI)
  • *

    One patient from the strength-training group dropped out of the study after the first year because of a lack of motivation for the training. See Patients and Methods for a description of the exercise groups. Values are the mean ± SD. 95% CI = 95% confidence interval; ESR = erythrocyte sedimentation rate; VAS = visual analog scale; DAS28 = Disease Activity Score in 28 swollen and 28 tender joints.

  • P < 0.05.

  • P < 0.01.

  • §

    P < 0.001.

ESR (mm/hour)
 Baseline24.4 ± 17.824.8 ± 15.7−0.4 (−8.8 to 8.2)
 6 months9.7 ± 9.516.7 ± 12.7−7.0 (−12.7 to −1.3)
 12 months9.5 ± 7.517.3 ± 16.1−7.8 (−14.1 to −1.4)
 18 months8.4 ± 7.215.5 ± 10.9−7.1 (−11.9 to −2.3)
 24 months10.9 ± 9.815.4 ± 11.5−4.5 (−10.0 to 0.9)
Pain (0–100-mm VAS)
 Baseline41.7 ± 19.541.3 ± 27.10.4 (−11.6 to 12.4)
 6 months20.0 ± 16.428.6 ± 23.1−8.6 (−18.9 to 1.5)
 12 months21.1 ± 20.624.2 ± 22.7−3.1 (−14.3 to 8.1)
 18 months14.6 ± 13.524.5 ± 21.3−9.9 (−19.2 to −0.6)
 24 months13.7 ± 16.224.9 ± 22.8−11.2 (−21.4 to −0.96)
Morning stiffness (minutes)
 Baseline72.4 ± 54.581.5 ± 90.4−9.1 (46.9 to 28.9)
 6 months31.8 ± 41.162.9 ± 75.5−31.1 (−62.0 to −25.7)
 12 months22.3 ± 31.842.5 ± 65.8−20.2 (−46.9 to 6.4)
 18 months18.3 ± 25.636.4 ± 51.3−18.1 (−39.4 to 3.1)
 24 months16.3 ± 21.337.7 ± 43.8−21.4 (−39.2 to −3.5)
DAS28 index (0–10 scale)
 Baseline4.4 ± 1.14.9 ± 1.1−0.5 (−1.1 to 0.003)
 6 months2.4 ± 1.03.4 ± 1.2−1.0 (−1.7 to −0.5)§
 12 months2.3 ± 1.03.0 ± 1.2−0.7 (−1.3 to −0.2)
 18 months2.0 ± 1.03.0 ± 1.9−1.0 (−1.5 to −0.4)§
 24 months2.2 ± 1.22.7 ± 1.2−0.5 (−1.2 to −0.004)
Larsen score (0–100 scale)
 Baseline0.9 ± 1.81.2 ± 2.0−0.3 (−1.4 to 0.6)
 6 months1.3 ± 2.31.3 ± 2.2−0.0 (−1.6 to 0.7)
 12 months1.4 ± 2.92.3 ± 2.7−0.9 (−2.2 to 0.7)
 18 months
 24 months1.5 ± 3.43.1 ± 3.5−1.6 (−3.1 to 0.4)

The maximum muscle strength values did not differ statistically between the groups at baseline (Figure 1). During the 24-month strength training, the mean ± SD knee extension strength per body mass increased by 59 ± 44% (P < 0.001) and 31 ± 27% (P < 0.001) in the strength-training group and the control group, respectively. The corresponding increases in trunk extension strength per body mass were 19 ± 28% (P < 0.001) versus 1 ± 19% (P not significant), trunk flexion strength 24 ± 19% (P < 0.001) versus 20 ± 43% (P = 0.007), and grip strength 50 ± 57% (P < 0.001) versus 24 ± 49% (P < 0.001) in the strength-training group and the control group, respectively. With the exception of trunk flexion strength, the muscle strength increases were significantly in favor of the strength-training group (P = 0.002–0.025).

thumbnail image

Figure 1. Changes in mean levels of maximum knee extension (A), grip (B), trunk extension (C), and trunk flexion (D) strength at 0, 6, 12, 18, and 24 months in patients with early rheumatoid arthritis randomly assigned to strength-training exercise (EG) or range of motion exercise (controls; CG).

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The study groups did not differ with regard to the extent of joint damage at baseline (Table 2). During the 24-month followup, the joint damage index increased only slightly in both study groups. Thus, the difference between the groups at the end of the study was also not significant.

As shown in Table 3, there were no significant intergroup differences in BMD at either of the measured sites at baseline. During the 24-month strength-training intervention, the femoral neck BMD was increased by 0.51 ± 1.64% (mean ± SD) in the strength-training group and decreased by 0.70 ± 2.25% in the controls. For BMD of the spine, these changes were an increase of 1.17 ± 5.34% and a decrease of 0.91 ± 4.07%, respectively. At the femoral neck, the intergroup difference was significant (P = 0.024).

Table 3. BMD in the femoral neck and lumbar spine at baseline and after 12 and 24 months in the entire rheumatoid arthritis study cohort and in patients of both groups who did and did not take prednisolone and/or alendronate*
 All study patientsAll study patients not taking prednisolone and/or alendronateAll study patients
Strength-training group (n = 31)Control group (n = 31)Strength-training group (n = 28)Control group (n = 18)Taking prednisolone and/or alendronate (n = 17)Not taking prednisolone and/or alendronate (n = 45)
  • *

    One patient from the strength-training group dropped out of the study after the first year because of a lack of motivation for the training. See Patients and Methods for a description of the exercise groups and the parameters for prednisolone and alendronate therapy. Values are the mean ± SD. BMD = bone mineral density.

  • P = 0.006.

  • P = 0.002.

Femoral neck BMD
 Baseline0.95 ± 0.120.95 ± 0.120.98 ± 0.010.99 ± 0.130.88 ± 0.120.98 ± 0.11
 12 months0.96 ± 0.120.95 ± 0.130.99 ± 0.100.99 ± 0.140.88 ± 0.110.99 ± 0.12
 24 months0.96 ± 0.120.93 ± 0.130.98 ± 0.110.98 ± 0.150.87 ± 0.100.98 ± 0.12
Lumbar spine BMD
 Baseline1.23 ± 0.201.20 ± 0.201.25 ± 0.191.21 ± 0.151.16 ± 0.201.24 ± 0.17
 12 months1.24 ± 0.201.18 ± 0.161.24 ± 0.181.22 ± 0.141.16 ± 0.211.23 ± 0.17
 24 months1.24 ± 0.191.18 ± 0.151.24 ± 0.181.21 ± 0.151.16 ± 0.211.22 ± 0.16

Seventeen of the 62 patients were treated for various periods with prednisolone and/or alendronate during the followup because of active disease and osteopenia, respectively. When these 17 subjects were removed from the analysis, the comparison of BMD values in the remaining patients (28 strength-training and 18 control subjects) showed no statistically significant between-group differences at either of the evaluated sites (Table 3).

However, when the group that took prednisolone and/or alendronate (n = 17) was compared with the group that did not (n = 45), there was a significant intergroup difference for BMD at the femoral neck for all 3 time points (P = 0.002–0.006). For BMD of the spine, there was a minor, but not statistically significant, difference between the groups. Both the femoral neck and spine BMD values remained unchanged in both users and nonusers during the followup. At baseline, the mean ± SD duration of RA symptoms in the users was 6.3 ± 4.2 months and the age 53 ± 7 years, compared with 12.0 ± 12.7 months (P not significant) and 48 ± 11 years (P = 0.045) in the nonusers. The users had statistically significantly lower HAQ scores (P < 0.021–0.047) during the followup compared with the nonusers. Further, their DAS28 index correlated negatively with the femoral neck BMD at month 24 (r = −0.38, P < 0.003).

The initial functional capacity, as measured by the HAQ and walking speed, was comparable between the groups at baseline (Table 4). The HAQ scores improved statistically significantly in both groups during the followup period. However, there were statistically significant between-group differences in the HAQ scores in favor of the strength-training group at months 18 and 24. The mean ± SD walking speed increased by 16 ± 17% (P < 0.001) in the strength-training group and by 9 ± 12% (P = 0.025) in the control group (Table 4).

Table 4. Parameters of functional capacity in patients with rheumatoid arthritis at baseline and after 6, 12, 18, and 24 months, by exercise group*
ParameterStrength-training group (n = 31)Control group (n = 31)Difference between groups (95% CI)
  • *

    One patient from the strength-training group dropped out of the study after the first year because of a lack of motivation for the training. See Patients and Methods for a description of the exercise groups. Values are the mean ± SD. 95% CI = 95% confidence interval; HAQ = Health Assessment Questionnaire.

  • P < 0.01.

  • P < 0.05.

HAQ index (0–3 scale)
 Baseline0.60 ± 0.530.77 ± 0.55−0.17 (−0.4 to 0.1)
 6 months0.25 ± 0.360.47 ± 0.51−0.22 (0.4 to 0.003)
 12 months0.20 ± 0.310.41 ± 0.48−0.21 (−0.4 to 0.003)
 18 months0.15 ± 0.260.39 ± 0.45−0.24 (−0.4 to −0.006)
 24 months0.13 ± 0.210.35 ± 0.45−0.22 (−0.4 to −0.004)
Walking speed (meters/second)
 Baseline1.9 ± 0.51.9 ± 0.40.00 (−0.18 to 0.32)
 6 months2.2 ± 0.62.0 ± 0.60.20 (−0.006 to 0.51)
 12 months2.2 ± 0.52.0 ± 0.60.20 (−0.008 to 0.47)
 18 months2.3 ± 0.52.1 ± 0.50.20 (−0.009 to 0.45)
 24 months2.4 ± 0.52.1 ± 0.60.30 (−0.10 to 0.47)

DISCUSSION

  1. Top of page
  2. Abstract
  3. PATIENTS AND METHODS
  4. RESULTS
  5. DISCUSSION
  6. REFERENCES

The results of the present study show that even minimally supervised at-home strength training for 24 months led to significant increases in maximum strength and general physical function in patients with early RA, without exacerbating the disease. Despite the substantial training effects on muscle strength, the BMD values remained, as expected, relatively unchanged over the 2-year study period.

In the strength-training group, maximum strength of the muscle groups evaluated increased by 19–59%. The corresponding change in the controls was 1–31%. In fact, the increases in muscle strength in favor of the strength-training group continued throughout the 24-month followup period. However, 1.4–1.5 weekly strength training sessions carried out in this study exceeded the normal daily tension levels of the muscles sufficiently to facilitate muscle performance (the overload principle). Although the exercise adherence in the experimental group was 70–75% of the planned rate, it was at the level achieved in other prospective interventions (24, 34). The present frequency of strength training did not inhibit the motivation of the patients for continuous training and left time and energy for other physical activities as well.

The control subjects were also able to increase their muscle strength. The improvement in muscle strength values in the controls was most probably due to an increase in the intensity of their physical activities, which was facilitated by a decrease in disease activity over time. The production of maximal voluntary muscle force is an unusual event, especially in RA patients, and for this reason, motor learning and improved coordination in strength measurements must be taken into account (35, 36). However, the increases in muscle strength in the control group were significantly inferior to those in the strength-training group, thus demonstrating the advantage of the applied dynamic strength–training regimen.

Osteoporosis is a well known extraarticular complication of RA (37). Although bone remodeling aberrations in RA have not been thoroughly defined, decreased physical activity and high levels of clinical disease activity as well as glucocorticoid treatment have been recognized as the most important contributory factors for the development of osteopenia (38–40). Most of the patients in the present study of early RA had normal BMD values at baseline. Thus, a realistic target for physical training was the maintenance of BMD and the prevention of disease-related bone loss. In addition to aerobic recreational physical activities, strength training consisted of exercises performed mostly in the supine, sitting, or standing positions using an elastic band for resistance. It seems that the “smooth” movements generally recommended for RA patients by, for example, the Arthritis Foundation (41, 42) and applied in the present study were sufficient to maintain, but insufficient to increase, BMD values. Previous studies on biking, swimming, or rowing (43–45) suggest that these typical non–weight-bearing exercises do not generate the necessary ground-reaction forces on the skeleton to increase BMD. Although our exercise modality has not been proven to be beneficial for bone density, it has many other benefits, such as increased muscle strength and walking speed, which in turn, may result in a lower risk of falling and an increase in daily activity levels.

Statistically significantly lower femoral neck BMD was found in the 17 patients who had more active disease compared with the value in the other 45 patients with less active RA. The difference between the groups was present at baseline—before the institution of glucocorticoid treatment—and persisted at months 12 and 24. A minor, not statistically significant, difference in spine BMD was also detected between these groups. On the other hand, during the 24-month followup, the contribution of glucocorticoids to inflammation and of alendronate to bone resorption apparently had a positive influence on these subjects to maintain their BMD at the baseline level by improving their capacity for physical activity. Some studies suggest that patients with clinically active disease receiving steroid therapy lose BMD significantly more rapidly than patients with inactive disease (3, 6). In the present study, the bone loss due to active disease was noted even before the initiation of glucocorticoids, which indicates that RA patients need early and effective treatment with DMARDs.

The progressive loss of function starts to develop early in RA. Inflammation disturbs bodily functions, which leads to restrictions in daily activities, tasks, and behaviors (46–48). In fact, one of the core aims of therapy for RA is the prevention or delay of disability. Dynamic strength training seems to be effective in improving muscle strength and, concomitantly, physical function, as demonstrated in this study by improvements in walking speed and self-reported physical function (HAQ). On the other hand, individually tailored dynamic muscle strength training had no negative effects on disease activity or structural joint damage.

In conclusion, the present study showed that a 24-month dynamic strength–training period results in increases in muscle strength and physical function, but it imposes only minor effects on BMD in the spine and femoral neck. High levels of disease activity, on the other hand, appear to play a central role in the loss of BMD in early RA. To improve long-term outcomes, patients with RA need to be assessed early in the disease course, and individualized therapies that include physical exercise as an integral element should be initiated in most cases.

REFERENCES

  1. Top of page
  2. Abstract
  3. PATIENTS AND METHODS
  4. RESULTS
  5. DISCUSSION
  6. REFERENCES
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