Physical activity and body composition in patients with ankylosing spondylitis

Stability and Volatility of Human Rest-Activity Rhythms: Insights from Very Long Actograms (VLAs)

Importance

Wrist-worn activity monitors provide biomarkers of health by non-obtrusively measuring the timing and amount of rest and physical activity (rest-activity rhythms, RARs). The morphology and robustness of RARs vary by age, gender, and sociodemographic factors, and are perturbed in various chronic illnesses. However, these are cross-sectionally derived associations from recordings lasting 4-10 days, providing little insights into how RARs vary with time.

Objective

To describe how RAR parameters can vary or evolve with time (~months).

Design Setting and Participants

48 very long actograms ("VLAs", ≥90 days in duration) were identified from subjects enrolled in the STAGES (Stanford Technology, Analytics and Genomics in Sleep) study, a prospective cross-sectional, multi-site assessment of individuals > 13 years of age that required diagnostic polysomnography to address a sleep complaint. A single 3-year long VLA (author GD) is also described.

Exposures/Intervention

None planned.

Main Outcomes and Measures

For each VLA, we assessed the following parameters in 14-day windows: circadian/ultradian spectrum, pseudo-F statistic ("F"), cosinor amplitude, intradaily variability, interdaily stability, acrophase and estimates of "sleep" and non-wearing.

Results

Included STAGES subjects (n = 48, 30 female) had a median age of 51, BMI of 29.4kg/m2, Epworth Sleepiness Scale score (ESS) of 10/24 and a median recording duration of 120 days. We observed marked within-subject undulations in all six RAR parameters, with many subjects displaying ultradian rhythms of activity that waxed and waned in intensity. When appraised at the group level (nomothetic), averaged RAR parameters remained remarkably stable over a ~4 month recording period. Cohort-level deficits in average RAR robustness associated with unemployment or high BMI (>29.4) also remained stable over time.

Conclusions and Relevance

Through an exemplary set of months-long wrist actigraphy recordings, this study quantitatively depicts the longitudinal stability and dynamic range of human rest-activity rhythms. We propose that continuous and long-term actigraphy may have broad potential as a holistic, transdiagnostic and ecologically valid monitoring biomarker of changes in chronobiological health. Prospective recordings from willing subjects will be necessary to precisely define contexts of use.

A physiological comparison of the new-over 70 years of age-marathon record holder and his predecessor: A case report

Purpose: This study assessed the body composition, cardiorespiratory fitness, fiber type and mitochondrial function, and training characteristics of a 71-year-old runner who broke the world record marathon of the men's 70-74 age category and held several other world records. The values were compared to those of the previous world-record holder. Methods: Body fat percentage was assessed using air-displacement plethysmography. V ˙ O 2 max , running economy, and maximum heart rate were measured during treadmill running. Muscle fiber typology and mitochondrial function were evaluated using a muscle biopsy. Results: Body fat percentage was 13.5%, V ˙ O 2 max was 46.6 ml kg^-1 min^-1, and maximum heartrate was 160 beats∙min^-1. At the marathon pace (14.5 km h^-1), his running economy was 170.5 ml kg^-1 km^-1. The gas exchange threshold and respiratory compensation point occurred at 75.7% and 93.9% of the V ˙ O 2 max , i.e., 13 km h^-1 and 15 km h^-1, respectively. The oxygen uptake at the marathon pace corresponded to 88.5% of V ˙ O 2 max . Vastus lateralis fiber content was 90.3% type I and 9.7% type II. Average distance was 139 km∙w^-1 in the year prior to the record. Conclusion: The 71-year-old world-record holder marathon showed a relatively similar V ˙ O 2 max , lower percentage of V ˙ O 2 max at marathon pace, but a substantially better running economy than his predecessor. The better running economy may result from an almost double weekly training volume compared to the predecessor and a high type I fiber content. He trained every day in the last ∼1.5 years and achieved international performance in his age group category with a small (<5% per decade) age-related decline in marathon performance.

Wearables for Measuring the Physical Activity and Sedentary Behavior of Patients With Axial Spondyloarthritis: Systematic Review

BACKGROUND

Axial spondyloarthritis (axSpA) is an inflammatory rheumatic disease associated with chronic back pain and restricted mobility and physical function. Increasing physical activity is a viable strategy for improving the health and quality of life of patients with axSpA. Thus, quantifying physical activity and sedentary behavior in this population is relevant to clinical outcomes and disease management. However, to the best of our knowledge, no systematic review to date has identified and synthesized the available evidence on the use of wearable devices to objectively measure the physical activity or sedentary behavior of patients with axSpA.

OBJECTIVE

This study aimed to review the literature on the use of wearable activity trackers as outcome measures for physical activity and sedentary behavior in patients with axSpA.

METHODS

PubMed, PEDro, and Cochrane electronic databases were searched in July 2021 for relevant original articles, with no limits on publication dates. Studies were included if they were original articles, targeted adults with a diagnosis of axSpA, and reported wearable device-measured physical activity or sedentary behavior among patients with axSpA. Data regarding the study's characteristics, the sample description, the methods used for measuring physical activity and sedentary behavior (eg, wearable devices, assessment methods, and outcomes), and the main results of the physical activity and sedentary behavior assessments were extracted.

RESULTS

A total of 31 studies were initially identified; 13 (13/31, 42%) met the inclusion criteria, including 819 patients with axSpA. All the studies used accelerometer-based wearable devices to assess physical activity. Of the 13 studies, 4 (4/31, 31%) studies also reported outcomes related to sedentary behavior. Wearable devices were secured on the wrists (3/13 studies, 23%), lower back (3/13, 23%), right hip (3/13, 23%), waist (2/13, 15%), anterior thigh (1/13, 8%), or right arm (1/13, 8%). The methods for reporting physical activity and sedentary behavior were heterogeneous. Approximately 77% (10/13) of studies had a monitoring period of 1 week, including weekend days.

CONCLUSIONS

To date, few studies have used wearable devices to quantify the physical activity and sedentary behavior of patients with axSpA. The methodologies and results were heterogeneous, and none of these studies assessed the psychometric properties of these wearables in this specific population. Further investigation in this direction is needed before using wearable device-measured physical activity and sedentary behavior as outcome measures in intervention studies in patients with axSpA.

TRIAL REGISTRATION

PROSPERO CRD42020182398; https://tinyurl.com/ec22jzkt.

INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID)

RR2-10.2196/23359.

Impact of lean and fat mass on disease activity and function in spondyloarthritis

BACKGROUND AND AIMS

Changes in body mass composition such as reduced lean and fat mass can occur in a patient with rheumatic diseases. However, data about body composition in spondyloarthritis (SpA) showed conflicting results. The aim of the present study was to assess by DXA the distribution of lean and fat mass in SpA patients compared to healthy controls and to investigate the association between body mass composition and disease characteristics.

METHODS

We conducted a cross-sectional case-control study including 50 SpA patients and 50 controls. Sociodemographic data as well as disease characteristics were assessed. Body composition measurements, biochemical and inflammatory serum markers were evaluated. Radiographic data (Bath Ankylosing Radiologic Index and the modified Stroke Ankylosing Spondylitis Spine Score was also recorded.

RESULTS

No statistically significant correlation was found between the two groups regarding bone mineral density, body mass distribution. However, a lower weight was observed in the study group compared to the control group (p=0.043). Male gender and younger age were associated with a higher lean mass (p=0.05). C-reactive protein (CRP) level was positively correlated with lean mass (r=0.38, p=0.023). Similarly, BASFI was higher in patients with lower fat mass (r=-0.42, p=0.024). A longer duration of NSAIDs intake was associated with a lower lean mass and a higher fat mass. However, no correlations were found between body mass composition and BASRI mSASSS scores as well as bone mineral density and calcium intake.

CONCLUSION

Our findings suggest that younger age, male gender, and axial phenotype were associated with higher lean mass.

Assessment of Intramuscular Fat and Correlation with Body Composition in Patients with Rheumatoid Arthritis and Spondyloarthritis: A Pilot Study

Rheumatoid arthritis (RA) and spondyloarthritis (SpA) are associated with changes in body composition. Ectopic intramuscular fat (IMAT) may alter muscle function and contribute to cardiometabolic disorders. In a pilot study, we analyzed IMAT in the calf with peripheral quantitative computed tomography (pQCT) and examined correlations between IMAT quantity and body composition parameters. In 20 patients with active RA and 23 with active SpA, IMAT was correlated with visceral fat (VAT; r = 0.5143 and 0.6314, respectively; p < 0.05) and total lean mass (r = 0.5414 and 0.8132, respectively; p < 0.05), but not with whole body fat mass. Total lean mass mediated 16% and 33% of the effects of VAT on IMAT in RA and SpA, respectively. In both RA and SpA, calf muscle area was correlated with total lean mass (r = 0.5940 and r = 0.8597, respectively; p < 0.05) and fat area was correlated with total body fat (r = 0.6767 and 0.5089, respectively; p < 0.05) and subcutaneous fat (r = 0.6526 and 0.5524, respectively; p < 0.05). Fat area was inversely correlated with handgrip and walking tests, and it was associated with disease activity and disability. We showed that ectopic IMAT, measured with pQCT, was correlated with VAT, but not with total body fat, in RA and SpA. This result suggests that metabolically active fat was specifically associated with IMAT.

Objective Measurements of Physical Activity and Sedentary Behavior Using Wearable Devices in Patients With Axial Spondyloarthritis: Protocol for a Systematic Review

Background

Axial spondyloarthritis (axSpA) is a subgroup of inflammatory rheumatic diseases. Practicing regular exercise is critical to manage pain and stiffness, reduce disease activity, and improve physical functioning, spinal mobility, and cardiorespiratory function. Accordingly, monitoring physical activity and sedentary behavior in patients with axSpA is relevant for clinical outcomes and disease management.

Objective

This review aims to determine which wearable devices, assessment methods, and associated metrics are commonly used to quantify physical activity or sedentary behavior in patients with axSpA.

Methods

The PubMed, Physiotherapy Evidence Database (PEDro), and Cochrane electronic databases will be searched, with no limit on publication date, to identify all the studies matching the inclusion criteria. Only original English-language articles published in a peer-reviewed journal will be included. The search strategy will include a combination of keywords related to the study population, wearable devices, physical activity, and sedentary behavior. We will use the Boolean operators “AND” and “OR” to combine keywords as well as Medical Subject Headings terms.

Results

Search strategy was completed in June 2020 with 23 records obtained. Data extraction and synthesis are currently ongoing. Dissemination of study results in peer-reviewed journals is expected at the end of 2021.

Conclusions

This review will provide a comprehensive and detailed synthesis of published studies that examine the use of wearable devices for objective assessment of physical activity and sedentary behavior in patients with axSpA.

Trial Registration

PROSPERO CRD42020182398; https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=182398

International Registered Report Identifier (IRRID)

PRR1-10.2196/23359

Physical activity in patients with axial spondyloarthritis in a multi-ethnic south-east Asian country

Background

Patients with axial spondyloarthritis (axSpA) may experience spinal stiffness and pain, leading to reduced physical function and quality of life. Despite the benefits of physical activity (PA) and exercise, previous studies have demonstrated lower levels of PA among patients with axSpA. This study aims to examine the patterns of PA among patients with axSpA compared to the general population in a multi-ethnic Asian country.

Methods

This was a cross-sectional study conducted between May 2016 and Jan 2017. Consecutive patients with axSpA were recruited at an outpatient rheumatology clinic at Singapore General Hospital, the largest tertiary hospital in Singapore. Controls were based on a previous cross-sectional study. PA was assessed using the Global Physical Activity Questionnaire (GPAQ).

Results

Seventy-four patients with axSpA were recruited and compared with 2679 controls. Lower proportion of patients with axSpA met the WHO recommendations for PA (axSpA = 77.0%, controls = 89.7%, p <  0.001). More patients with axSpA had high level of sedentary activity compared to controls (axSpA = 56.8%, controls = 36.1%, p <  0.001). Levels of PA did not differ between patients with inactive versus active axSpA disease (p = 0.91).

Conclusions

Proportion of patients with axSpA meeting the WHO recommendations for PA differed significantly from the general population, and level of PA did not differ between patients with active and inactive axSpA disease. Higher levels of sedentary activity were seen in patient with axSpA compared to the general population, highlighting the need for interventions to promote PA among patients with axSpA.

Supplementary Information

The online version contains supplementary material available at 10.1186/s41927-021-00211-5.

Physical therapy in axial spondyloarthritis: guidelines, evidence and clinical practice

PURPOSE OF REVIEW

Physical therapy is recommended for the management of axial spondyloarthritis (axSpA) with the focus of promoting physical activity and prescribing exercise within four domains, outlined recently by the European League against Rheumatism (EULAR): aerobic, resistance, flexibility and neuro-motor exercise. There is an increasing evidence base to support physical therapy interventions in axSpA.

RECENT FINDINGS

We present evidence supporting the use of exercise as treatment for patients with axSpA, recent updates among different exercise modalities, and make clear its critical place in the management of this condition. Recent large, multicentre data have shown that high-intensity exercise can improve disease activity and also positively impact cardiovascular risk factors in these patients. Although international treatment guidelines advocate the inclusion of physical activity and exercise for the optimal management of axSpA, specific guidance about the amount of exercise required to produce a beneficial effect is lacking.

SUMMARY

Exercise must be used in the management of axSpA, and whilst hydrotherapy and flexibility exercises are traditionally the main focus, other applications, such as strength training, may be underutilized domains. Further studies are needed to determine the dose-response relationship between exercise and axSpA patient subsets.

Comparison of physical activity levels among different sub-types of axial spondyloarthritis patients and healthy controls

OBJECTIVES

The aim was to compare the physical activity levels among radiographic axial spondyloarthritis (axSpA) patients, non-radiographic axSpA patients, and healthy controls and investigating the possible relationships between physical activity level and clinical features.

METHODS

Thirty-four patients with radiographic axSpA (24 male), 33 patients with non-radiographic axSpA (23 male), and 35 age and sex-matched healthy controls (24 male) were included. The patients were assessed with Bath Ankylosing Spondylitis Disease Activity Index, Bath Ankylosing Spondylitis Functional Index, Bath Ankylosing Spondylitis Metrology Index, Ankylosing Spondylitis Quality of Life Questionnaire, Hospital Anxiety and Depression Scale, Tampa Scale of Kinesiophobia. Physical activity was measured by using an accelerometer (Actigraph wGT3X-BT).

RESULTS

Physical and disease-related characteristics were comparable between groups (p > .05). Radiographic axSpA patients showed lesser physical activity compared to non-radiographic axSpA patients and healthy controls (p < .05). No difference was detected between non-radiographic axSpA patients and healthy controls (p > .05). Physical activity levels were correlated with different clinical features for each sub-type of axSpA. Decreased spinal mobility is the most correlated disease characteristic with lower physical activity level for both sub-types.

CONCLUSION

It seems that disease sub-type in axSpA may alter the physical activity levels. Increasing physical activity levels might need different approaches for different sub-types of axSpA.

Association Between Familial Mediterranean Fever and Cachexia in Females

Objectives

This study aims to investigate the association between familial Mediterranean fever (FMF) and cachexia in females.

Patients and methods

The study included 32 female FMF patients (median age 27.50 years; range, 18 to 50 years) and 30 female healthy controls (median age 32 years; range, 18 to 50 years). Patients were classified according to Tel-Hashomer criteria. Circumference of arm, waist, and thigh was recorded. Short form 36 (SF-36) and Multidimensional Assessment of Fatigue (MAF) scale were applied. Composition of the body was measured with dual X-ray absorption. Muscle strength was measured with an isokinetic dynamometer, and strength of hand grip was measured from dominant hand with a hand dynamometer. C-reactive protein, erythrocyte sedimentation rate, fibrinogen and serum creatinine kinase (CK) levels were recorded.

Results

Body mass index was significantly higher in controls. Twelve patients and one control had cachexia. CK level was significantly higher in patients than controls. Mass of muscle without fat was significantly higher in patients than controls. Peak torque values of extension and flexion at the velocity of 60°/second [Newton meter (Nm)], and value of total work during extension at the velocity of 240°/second (Nm) in isokinetic measures were significantly higher in controls. MAF score was significantly higher in patients with cachexia than patients without cachexia where the subscale scores of SF-36, except the vitality score, were significantly lower in patients with cachexia. However, Tel-Hashomer score was significantly higher in patients with cachexia.

Conclusion

This study pointed at a significant association between cachexia and FMF in females. Muscle endurance was not affected in FMF patients with cachexia; however, decreased muscle strength, impaired quality of life and increased fatigue were observed in these patients.

Physical activity and sedentary behaviour and their associations with clinical measures in axial spondyloarthritis

Engaging in physical activity (PA) is a key aspect in the management of axial spondyloarthritis (axial SpA), however, its relationship with clinical measures is unknown. Previous research has mainly focused on subjective methods of measuring PA and sedentary behaviour (SB). The aim of this study was to explore the associations between objectively measured PA and SB with clinical measures in people with established axial SpA. Fifty participants were recruited from secondary-care rheumatology outpatient services in Glasgow, UK. Clinical measures collected included; Bath Ankylosing Spondylitis Disease Activity Index (BASDAI), Bath Ankylosing Spondylitis Functional Index (BASFI), Bath Ankylosing Spondylitis Metrology Index (BASMI), Ankylosing Spondylitis Quality of Life (ASQOL) and the Six Minute Walk Test (6MWT). PA and SB were measured using the activPAL3 tri-axial accelerometer. Data from forty-five participants were included (23 males, average age 49 ± 12 years). Participants accumulated an average of 93.2 ± 41.5 min/day walking with an average of 7200 ± 3397 steps/day. The majority of the day (65%) was spent sitting, accumulated in prolonged bouts. Walking time and steps taken/day were associated with better BASFI (r = − 0.395, p = 0.007 and r = − 0.404, p = 0.006), ASQOL (r = − 0.375, p = 0.011 and r = − 0.361, p = 0.015) and 6MWT (r = 0.396, p = 0.007 and r = 0.421, p = 0.004); while longer walking events were associated with better BASMI (rho = − 0.352, p = 0.018), BASFI (rho = − 0.316, p = 0.034) and 6MWT (rho = 0.404, p = 0.006). SB was associated with worse ASQOL (r = 0.380, p = 0.010) and 6MWT (6MWT, r = − 0.357, p = 0.016). In people with axial SpA PA is associated with better function, exercise capacity and spinal mobility, while SB is associated with lower exercise capacity and poor quality of life. These findings support the promotion of PA and reduction of SB in people with axial SpA.

Longterm Effect on Leisure Time Physical Activity Level in Individuals with Axial Spondyloarthritis: Secondary Analysis of a Randomized Controlled Trial

OBJECTIVE

To explore the longterm effect of a 3-month exercise program on leisure time physical activity level in individuals with axial spondyloarthritis (axSpA).

METHODS

A secondary analysis was performed on data from 100 individuals with axSpA who were included in a randomized controlled trial. The exercise group (EG) participated in a 3-month exercise program while the control group (CG) received no intervention. Physical activity during leisure time was measured with a questionnaire (physically active: ≥ 1 h/week with moderate/vigorous intensity physical activity). Disease activity was measured with the Ankylosing Spondylitis Disease Activity Scale (ASDAS; higher score = worst). Statistical analyses were performed on an intention-to-treat basis using chi-square tests, logistic regression, and mixed models.

RESULTS

At the 12-month followup, significantly more individuals in the EG than in the CG were physically active [29 (67%) vs 13 (30%), p < 0.001] and exercised 2-3 times/week [25 (58%) vs 15 (34%), p = 0.02], and fewer exercised at light intensity [3 (8%) vs 14 (44%), p = 0.002]. "Participation in the EG" (OR 6.7, 95% CI 2.4-18.6, p < 0.001) and "being physically active at baseline" (OR 4.7, 95% CI 1.4-15.8, p = 0.01) were the factors most associated with being physically active. There were no differences between the groups in ASDAS (p = 0.79).

CONCLUSION

A 3-month exercise program had a beneficial longterm effect on leisure time physical activity in individuals with axSpA, thus indicating a more beneficial health profile. Still, few individuals continued the intensive program, and there was no difference between the groups in disease activity after 12 months. (ClinicalTrials.gov: NCT02356874).

Association between sarcopenia and rheumatological diseases

Sarcopenia (“sarx” for muscle, “penia” for loss) is an important problem in the elderly. Although muscle loss is a part of natural aging, excessive loss that limits physical activity is considered pathological. Sarcopenia is associated with age, malnutrition, physical inactivity, inflammatory stress and hormonal changes. Although relationships between sarcopenia and various chronic inflammatory diseases have been shown, the role of rheumatologic disease in sarcopenia development is currently unknown. Our aim in this mini-review was to increase the awareness of clinicians to sarcopenia, and to evaluate studies in which the relationship between sarcopenia and rheumatologic diseases was investigated. We also aimed to determine whether the available literature was sufficient to confirm a strong relationship between these conditions. Although our findings showed that diseases such as rheumatoid arthritis, osteoarthritis and systemic sclerosis may have a role in sarcopenia development and progress, the methodologies and results of the majority of studies were insufficient in determining direct causal relationships. We believe future studies would benefit from focusing on the factors and causes of sarcopenia, with a goal of determining the factors associated with rheumatologic disease that are most effective in sarcopenia development.

High intensity exercise for 3 months reduces disease activity in axial spondyloarthritis (axSpA): a multicentre randomised trial of 100 patients

Background

Exercise is considered important in the management of patients with rheumatic diseases, but the effect of high intensity exercises on disease activity is unknown.

Objective

To investigate the effectiveness of high intensity exercises on disease activity in patients with axial spondyloarthritis (axSpA).

Method

Assessor blinded multicentre randomised controlled trial. 100 patients (aged from their 20s to their 60s) with axSpA were randomly assigned to an exercise group or to a no-intervention control group. The exercise group performed cardiorespiratory and muscular strength exercises at high intensity over 3 months. The control group received standard care and was instructed to maintain their usual physical activity level. Primary outcome was disease activity measured with the Ankylosing Spondylitis (AS) Disease Activity Scale (ASDAS, higher score=worst) and the Bath AS Disease Activity Index (BASDAI, 0–10, 10=worst). Secondary outcomes were inflammatory markers, physical function and cardiovascular (CV)-health. There was patient involvement in the design and reporting of this study.

Results

97 of the 100 (97%) randomised patients completed the measurements after the intervention. There was a significant treatment effect of the intervention on the primary outcome (ASDAS: −0.6 [–0.8 to –0.3], p<0.001 and BASDAI: −1.2 [–1.8 to –0.7], p<0.001). Significant treatment effects were also seen for inflammation, physical function and CV-health.

Conclusion

High intensity exercises reduced disease symptoms (pain, fatigue, stiffness) and also inflammation in patients with axSpA. It improves patients’ function and CV health. This debunks concerns that high intensity exercise might exacerbate disease activity in patients with axSpA.

Trial registration number

NCT02356874.

Physical activity, energy expenditure and sedentary parameters in overfeeding studies - a systematic review

BACKGROUND

It has been proposed that compensations in physical activity, energy expenditure and sedentary parameters can occur as a result of overfeeding studies in order to maintain body weight; however, the evidence has not yet been systematically reviewed.

METHODS

The current study systematically reviewed the literature on this subject to determine the common tools used in overfeeding studies and to explore whether overfeeding produces changes in physical activity, energy expenditure and sedentary parameters. Eight electronic databases were searched to identify experimental studies using keywords pertaining to overfeeding, exercise, physical activity and sedentariness. Articles included healthy adults (aged 18-64 years) participating in an overfeeding study that examined at least one parameter of sedentary, energy expenditure or physical activity. Of 123 full-text articles reviewed, 15 met the inclusion criteria.

RESULTS

The common tools used in overfeeding studies were doubly labeled water (n = 6), room calorimeter (n = 4), accelerometer (n = 7), pedometer (n = 3), radar sensor (n = 4) and survey (n = 1). Parameters partaining to energy expenditure increased between 7 to 50% with different overfeeding duration. Physical activity parameters, such as number of steps and spontaneous activity, increased or decreased significantly in three studies, while five studies showed no significant change. Sedentary parameters were examined by only one study and its results were not significant after 3 days of overfeeding. Methodological issues existed concerning the small number of studies, disparities in sedentary and physical activity parameters and various definitions of free-living experimental conditions and physical activity limits.

CONCLUSIONS

There is actually a use of many tools and a large variation of parameters for physical activity in overfeeding studies. Contradictory findings showed changes in physical activity parameters following overfeeding and limited findings support the absence of changes in sedentariness. While energy expenditure parameters are more numerous and all show an increase after an overfeeding period, further studies are required to confirm changes in physical activity and sedentary parameters.

[Becoming older with axial spondyloarthritis]

The combination of physiological age-related changes (e. g. reduction in muscle mass and function, reduction in organ function and degenerative changes in joints) and disease-specific changes of ankylosing spondylitis (AS), make older AS patients vulnerable for additional diseases. In this patient population various processes lead to a reduction in physical function, changes in posture, osteoporosis and sarcopenia, which then can result in falls and fractures, especially vertebral fractures. Mortality is increased in patients with AS, particularly in men due to an increase in cardiovascular mortality. Although the standardized assessment of cardiovascular risk factors in patients with inflammatory rheumatic diseases (independent of age) has been recommended for years, it is rarely done in clinical practice. Overall, data on comorbidities and risk factors are only available for AS patients and are lacking for other forms of spondyloarthritides.

Muscle Mass, Strength, Mobility, Quality of Life, and Disease Severity in Ankylosing Spondylitis Patients: A Preliminary Study

Objective

To determine if there is muscle mass reduction in patients with ankylosing spondylitis (AS) compared to the general population and to examine the relationship between skeletal muscle mass, quality of life (QOL), strength, and mobility in patients with AS.

Methods

A total of 30 AS patients were enrolled in this study. Skeletal muscle mass was measured by bioelectrical impedance analysis, and it was expressed as the skeletal muscle mass index (SMI). QOL was assessed using the EuroQOL (EQ-5D). To measure mobility, the modified Schöber test and chest expansion test were used. To measure grip strength as a measure of muscle strength, we used the hydraulic hand dynamometer. Additionally, we divided the patients into two groups according to the degree of X-ray finding and compared the differences between the two groups.

Results

There was no significant reduction in skeletal muscle mass in patients with AS compared to the general population. Also, there was no significant correlation between SMI and QOL. On the other hand, there was a significant positive correlation between SMI and mobility, and grip strength. A significant positive correlation was found between mobility and QOL. Additionally, there was a statistically significant difference in mobility between the two groups according to the degree of X-ray finding.

Conclusion

Maintaining muscle mass in AS patients may not be helpful for improving QOL, but it may contribute to achieving adequate mobility and strength.

Muscle wasting in male TNF-α blocker naïve ankylosing spondylitis patients: a comparison of gender differences in body composition

Objective

To assess gender differences in body composition (BC) in a cohort of AS patients naïve to TNF-α blockers.

Methods

Patients included fulfilled the Modified New York criteria for AS. Demographic information and disease activity measures (ASDAS and BASDAI) were reported. BC was measured by whole body DXA. Body fat percentage (BF%), fat mass index (FMI), fat free mass index (FFMI) and android/gynoid fat ratio were reported and compared between men and women and with the reference population (percentiles).

Results

Seventy consecutive patients were included; 60% were men. Demographic variables were similar, except for dyslipidaemia (57.1% of men; 14.3% of women). Women had significantly more fat (BF%, FMI), and less muscle (FFMI) than men, but below the median of the reference population. Male AS patients had a markedly low FFMI (31.7th percentile) compared with the reference population. In the whole group, after multivariate analysis, an ASDAS CRP >3.5 was related to lower fat free mass content. In men, a significant relationship between having a high disease activity (ASDAS, BASDAI) and lower BF% or FMI percentile was found, but in women it was the opposite.

Conclusion

Muscle wasting, measured as low FFMI compared with the reference population, was found in male TNF-α blocker naïve AS patients, especially in those with active disease. Women had higher volumes of body fat than men, but near the median of the reference population. The relationships between fat content and disease activity support the complex association between adipose tissue and inflammation.

Effect of cardiorespiratory and strength exercises on disease activity in patients with inflammatory rheumatic diseases: a systematic review and meta-analysis

OBJECTIVE

To investigate the effects of cardiorespiratory and strength exercises on disease activity for patients with inflammatory rheumatic diseases (IRDs).

DESIGN

A systematic review with meta-analysis registered at PROSPERO (CRD42015020004).

PARTICIPANTS

Patients with IRDs.

DATA SOURCES

The databases MEDLINE, AMED, Embase and CINAHL were searched from inception up to April 2016.

ELIGIBILITY CRITERIA FOR SELECTING STUDIES

Trials were included if they were randomised controlled trials of adults with IRDs, comparing the effect of cardiorespiratory and strength exercises with usual care on disease activity and followed the American College of Sports Medicine's exercise recommendations. The primary outcome was disease activity in terms of inflammation, joint damage and symptoms.

DATA SYNTHESIS

Data were pooled in a random-effect model for all outcomes, and standardised mean differences (SMDs) were calculated. The quality of evidence was evaluated according to the Grading of Recommendations Assessment, Development and Evaluation approach.

RESULTS

Twenty-six trials with a total of 1286 participants were included. There was high to moderate quality evidence, for a small beneficial effect on disease activity scores (0.19 (95% CI 0.05 to 0.33), p<0.01) and joint damage (SMD 0.27 (95% CI 0.07 to 0.46), p<0.01). Furthermore, moderate quality evidence for a small beneficial effect on erythrocyte sedimentation rate (SMD 0.20 (95% CI 0.0 to 0.39), p=0.04) and for no effect on C reactive protein (SMD -0.14 (95% CI -0.37 to 0.08), p=0.21). Beneficial effects were also seen for symptoms.

CONCLUSIONS

The results of this review suggest beneficial effects of exercises on inflammation, joint damage and symptoms in patients with IRDs.

The Effect of Anti-Tumor Necrosis Factor-Alpha Treatment on Muscle Performance and Endurance in Patients With Ankylosing Spondylitis: A Prospective Follow-Up Study

Objectives

This study aims to evaluate muscle performance by using isokinetic dynamometer before and at third month of anti-tumor necrosis factor-alpha treatment in ankylosing spondylitis patients.

Patients and methods

Thirty ankylosing spondylitis patients (23 males, 7 females; mean age 39.3±8.6 years; range 18 to 45 years) starting on anti- tumor necrosis factor-alpha treatment and 30 healthy controls (23 males, 7 females; mean age 39.1±8.8 years; range 18 to 48 years) with similar age, body mass index, and sex were enrolled. The clinical anthropometric measurements of chest expansion, lumbar Schober test, hand-finger floor distance and visual analog scale-global, C-reactive protein, erythrocyte sedimentation rate, Ankylosing Spondylitis Disease Activity Score-C-reactive protein and Ankylosing Spondylitis Disease Activity Score-erythrocyte sedimentation rate, Bath Ankylosing Spondylitis Disease Activity Index, Bath Ankylosing Spondylitis Metrology Index, Bath Ankylosing Spondylitis Disease Activity Index, Bath Ankylosing Spondylitis Metrology Index were determined before and at third month of the treatment.

Results

There was no statistically significant difference in age, sex and, body mass index between the groups (p>0.05). A statistically significant difference was detected between 60 °/second and 180 °/second peak torque in angular velocity of flexor and extensor muscles (p<0.05). A significant difference was detected in respect to total work of patients with 180 °/second peak torque in angular velocity of flexor and extensor muscles (p<0.05). There was a statistically significant difference between the findings of 60 °/second and 180 °/second peak torque in angular velocity of flexor and extensor muscles (p<0.05). Isokinetic test results were better at third month after treatment than before treatment.

Conclusion

The results of this study showed that both functional limitations and performance and endurance of muscles may be improved with anti-tumor necrosis factor-alpha treatment in ankylosing spondylitis patients.

Reduced Appendicular Lean Body Mass, Muscle Strength, and Size of Type II Muscle Fibers in Patients with Spondyloarthritis versus Healthy Controls: A Cross-Sectional Study

Introduction. The purpose of this study was to investigate body composition, muscle function, and muscle morphology in patients with spondyloarthritis (SpA). Methods. Ten male SpA patients (mean ± SD age 39 ± 4.1 years) were compared with ten healthy controls matched for sex, age, body mass index, and self-reported level of physical exercise. Body composition was measured by dual energy X-ray absorptiometry. Musculus quadriceps femoris (QF) strength was assessed by maximal isometric contractions prior to test of muscular endurance. Magnetic resonance imaging of QF was used to measure muscle size and calculate specific muscle strength. Percutaneous needle biopsy samples were taken from m. vastus lateralis. Results. SpA patients presented with significantly lower appendicular lean body mass (LBM) (p = 0.02), but there was no difference in bone mineral density, fat mass, or total LBM. Absolute QF strength was significantly lower in SpA patients (p = 0.03) with a parallel trend for specific strength (p = 0.08). Biopsy samples from the SpA patients revealed significantly smaller cross-sectional area (CSA) of type II muscle fibers (p = 0.04), but no difference in CSA type I fibers. Conclusions. Results indicate that the presence of SpA disease is associated with reduced appendicular LBM, muscle strength, and type II fiber CSA.

Is there a relation between pre-sarcopenia, sarcopenia, cachexia and osteoporosis in patients with ankylosing spondylitis?

Background

Osteoporosis is a well-known complication of ankylosing spondylitis (AS). However, data about body composition modifications and muscle performance showed conflicting results. The aim of the study was to determine the prevalence and risk factors of pre-sarcopenia, sarcopenia and cachexia in patients with AS and analyze its relationship with bone loss and symptomatic and severity parameters of the disease.

Methods

Sixty-seven consecutive male patients with AS (mean age of 40.9 ± 11.0 years) and 67 healthy controls were studied. Body composition and bone mineral density (BMD) scans were obtained using DXA. The fat-free mass index (FFMI; fat-free mass divided by height squared) and the percent of fat mass (%FM) were calculated. Pre-sarcopenia was defined by low skeletal muscle mass (SMI <7.25 kg/m²), sarcopenia by the combined presence of the two following criteria: SMI <7.25 kg/m² and a low muscle strength (handgrip strength <30 kg) or a low muscle performance (timed get-up-and-go test >10 s) and cachexia by a BMI <20 kg/m² plus 3 from the 5 following parameters: anorexia, fatigue, handgrip strength <30 kg, CRP >5 mg/l, SMI <7.25 kg/m².

Results

Pre-sarcopenia, sarcopenia, cachexia, and osteoporosis prevalences were (50.4, 34.3, 11.9, and 16.0) respectively. Patients had a mean 3 kg significant decrease in FFM and a 1 kg/m² decrease in appendicular mass vs. healthy controls. Pre-sarcopenia, sarcopenia and cachexia were significantly associated to higher BASDAI levels and low BMD.

Conclusion

Our study showed that men with AS had a statistically significant reduction in total and appendicular lean mass that is related to higher disease activity and significantly associated to bone loss.

Electronic supplementary material

The online version of this article (doi:10.1186/s12891-016-1155-z) contains supplementary material, which is available to authorized users.

Fatigue, patient reported outcomes, and objective measurement of physical activity in systemic lupus erythematosus

OBJECTIVE

Fatigue is a common symptom in systemic lupus erythematosus (SLE), and engaging in physical activity may reduce fatigue. We aimed to characterize relationships between fatigue, other health status measures assessed with the Patient Reported Outcomes Measurement Information System (PROMIS) instruments, and accelerometer-based physical activity measurements in patients with SLE. The internal consistency of each PROMIS measure in our SLE sample was also evaluated.

METHODS

This cross-sectional study analyzed 123 adults with SLE. The primary fatigue outcome was Fatigue Severity Scale score. Secondary outcomes were PROMIS standardized T-scores in seven health status domains. Accelerometers were worn for seven days, and mean daily minutes of light, moderate/vigorous, and bouted (10 minutes) moderate/vigorous physical activity were estimated. Cronbach's alpha was determined for each PROMIS measure to assess internal consistency. Relationships between Fatigue Severity Scale, PROMIS, and physical activity were summarized with Spearman partial correlation coefficients (r), adjusted for average daily accelerometer wear time.

RESULTS

Mean Fatigue Severity Scale score (4.3, SD 1.6) was consistent with clinically relevant levels of fatigue. Greater daily and bouted moderate/vigorous physical activity minutes correlated with lower Mean Fatigue Severity Scale score (r = -0.20, p = 0.03 and r = -0.30, p = 0.0007, respectively). For PROMIS, bouted moderate/vigorous physical activity minutes correlated with less fatigue (r = -0.20, p = 0.03). PROMIS internal consistency was excellent, with Cronbach's alpha > 0.90 for each domain. Mean PROMIS T-scores for fatigue, pain interference, anxiety, sleep disturbance, sleep-related impairment, and physical function were worse than reported for the general US population. More moderate/vigorous physical activity minutes were associated with less pain interference (r = -0.22, p = 0.01). Both light physical activity and moderate/vigorous physical activity minutes correlated with better physical function (r = 0.19, p = 0.04 and r = 0.25, p = 0.006, respectively).

CONCLUSION

More time spent in moderate/vigorous physical activity was associated with less fatigue (Fatigue Severity Scale and PROMIS), less pain interference, and better physical function (PROMIS). PROMIS had excellent internal consistency in our SLE sample, and six of seven PROMIS measures indicated poorer average health status in SLE patients compared with the general US population.

Accelerometer Quantification of Physical Activity and Activity Patterns in Patients with Ankylosing Spondylitis and Population Controls

Objective.

To compare the total amount of physical activity (TPA) and time spent in various activity intensities of patients with ankylosing spondylitis (AS) and population controls, and to explore factors related to physical activity (PA).

Methods.

Subjects were asked to wear a triaxial accelerometer for 7 days and to complete a series of questionnaires. Multivariable regressions were used to assess generic determinants of TPA in patients and controls, and in patients to explore demographic and disease-specific determinants of various PA intensities.

Results.

One hundred and thirty-five patients [51 ± 13 yrs, 60% men, body mass index (BMI) 26.0 ± 4.3 kg/m2] and 99 controls (45 ± 12 yrs, 67% men, BMI 25.1 ± 4.3 kg/m2) were included. Patients did not differ from controls regarding TPA (589 vs 608 vector count/min, p = 0.98), minutes/day spent in sedentary (524 vs 541, p = 0.17), and light PA (290 vs 290 p = 0.95), but spent fewer minutes/day in moderate to vigorous PA (MVPA; 23 vs 30 min/day, p = 0.006). Perceived functional ability (physical component summary of the Medical Outcomes Study Short Form-36) and BMI were associated with TPA independent of having AS (p interaction = 0.21 and 0.94, respectively). Additional analyses in patients showed that time spent in MVPA was negatively influenced by BMI, physical function (Bath AS Functional Index), and disease duration. In patients ≥ 52 years old, a higher Bath AS Disease Activity Index was associated with less time spent in sedentary and more time spent in light activities.

Conclusion.

Compared with controls, patients with AS had similar TPA, but may avoid engagement in higher intensities of PA. Lower levels of functional ability and higher BMI were associated with lower TPA in both patients and controls.

Self-reported and objectively measured physical activity in adults with systemic lupus erythematosus

OBJECTIVE

Most estimates of physical activity (PA) patterns in systemic lupus erythematosus (SLE) are based on subjective self-report measures prone to error. The aims of this study were to obtain objective measurements of PA using an accelerometer and estimates of energy expenditure based on the self-reported International Physical Activity Questionnaire (IPAQ), and to describe their relationship.

METHODS

The Activity in Lupus To Energize and Renew study, a cross-sectional study of PA, included 129 persons with SLE. Accelerometer measures >7 days included total daily activity counts and minutes of moderate-vigorous PA (MVPA). Each person completed the IPAQ via telephone interview. Spearman's correlations (r) and 95% confidence intervals (95% CIs) assessed associations between accelerometer and IPAQ.

RESULTS

Daily PA means and SDs from accelerometer measures were 502,910 ± 118,755 for total daily activity counts and 40 ± 30 minutes for MVPA. The median (interquartile range) MET minutes/day for IPAQ intensities were: 400 (159-693) for total; 83 (26-184) for walking; and 231 (77-514) for MVPA, and domains were: 0 (0-73) for work; 28 (0-85) for active transportation; 77 (26-231) for domestic and garden; and 57 (0-213) for leisure. Associations between accelerometer measures and IPAQ were 1) total daily count versus IPAQ total: r = 0.21 (95% CI 0.03, 0.37) and 2) MVPA versus IPAQ moderate-vigorous: r = 0.16 (95% CI - 230.02, 0.33).

CONCLUSION

Accelerometer measures and IPAQ energy expenditure estimates were moderately correlated. IPAQ provided descriptive PA data, whereas accelerometers captured all daily activities, which can help assess guideline attainment. The choice of IPAQ versus accelerometer measure should include considering the purpose for which PA is measured.

Obesity and inflammatory arthritis: impact on occurrence, disease characteristics and therapeutic response

Overweight and obesity are increasing worldwide and now reach about one-third of the world's population. Obesity also involves patients with inflammatory arthritis. Knowing the impact of obesity on rheumatic diseases (rheumatoid arthritis, ankylosing spondylitis and psoriatic arthritis) is thus an important issue. This article first reviews the epidemiological and clinical data available on obesity in inflammatory rheumatic diseases, that is, its impact on incident disease, disease characteristics and the therapeutic response. The second part of this review gives an overview of the factors potentially involved in the specifics of inflammatory arthritis in patients with obesity, such as limitations in the clinical assessment, diet, microbiota and adipokines.

Physical functioning in patients with ankylosing spondylitis: comparing approaches of experienced ability with self-reported and objectively measured physical activity

BACKGROUND

Physical functioning can be assessed by different approaches that are characterized by increasing levels of individual appraisal. There is insufficient insight into which approach is the most informative in patients with ankylosing spondylitis (AS) compared with control subjects.

OBJECTIVE

The objective of this study was to compare patients with AS and control subjects regarding 3 approaches of functioning: experienced ability to perform activities (Bath Ankylosing Spondylitis Functional Index [BASFI]), self-reported amount of physical activity (PA) (Baecke questionnaire), and the objectively measured amount of PA (triaxial accelerometer).

METHODS

This case-control study included 24 AS patients and 24 control subjects (matched for age, gender, and body mass index). Subjects completed the BASFI and Baecke questionnaire and wore a triaxial accelerometer. Subjects also completed other self-reported measures on disease activity (Bath AS Disease Activity Index), fatigue (Multidimensional Fatigue Inventory), and overall health (EuroQol visual analog scale).

RESULTS

Both groups included 14 men (58%), and the mean age was 48 years. Patients scored significantly worse on the BASFI (3.9 vs 0.2) than their healthy peers, whereas PA assessed by Baecke and the accelerometer did not differ between groups. Correlations between approaches of physical functioning were low to moderate. Bath Ankylosing Spondylitis Functional Index was associated with disease activity (r = 0.49) and physical fatigue (0.73) and Baecke with physical and activity related fatigue (r = 0.54 and r = 0.54), but total PA assessed by accelerometer was not associated with any of these experience-based health outcomes.

CONCLUSIONS

Different approaches of the concept physical functioning in patients with AS provide different information. Compared with matched control subjects, patients with AS report more difficulties but report and objectively perform the same amount of PA.

Translation and cross-cultural adaptation of the Scleroderma Health Assessment Questionnaire to Brazilian Portuguese

CONTEXT AND OBJECTIVE

Systemic sclerosis is an autoimmune disease characterized by abnormalities of vascularization that may cause fibrosis of the skin and other organs and lead to dysfunction. It is therefore essential to have tools capable of evaluating function in individuals with this condition. The aim of this study was to translate the Scleroderma Health Assessment Questionnaire (SHAQ) into Portuguese, adapt it to Brazilian culture and test its validity and reliability.

DESIGN AND SETTING

The validation of SHAQ followed internationally accepted methodology, and was performed in university outpatient clinics.

METHODS

SHAQ was translated into Portuguese and back-translated. In the cultural adaptation phase, it was applied to 20 outpatients. Items not understood by 20% of the patients were modified and applied to another 20 outpatients. Twenty patients were interviewed on two different occasions to determine the validity and reliability of the questionnaire: two interviewers on the first occasion and one interviewer 14 days later. To determine the external validity, comparisons were made with Health Assessment Questionnaire (HAQ), Disabilities of the Arm, Shoulder and Hand (DASH) and short form-36 (SF-36).

RESULTS

In the interobserver evaluation, Pearson's correlation coefficient and the intraclass correlation coefficient were both 0.967. In the intraobserver evaluation, Pearson's correlation coefficient was 0.735 and the intraclass correlation coefficient was 0.687. Regarding external validity, SHAQ scores were statistically correlated with all measurements, except the general health domain of SF-36 and the work-related score (Q2) of DASH.

CONCLUSION

The Brazilian version of SHAQ proved to be valid and reliable for assessing function in patients with diffuse systemic sclerosis.

Physical activity assessment in patients with axial spondyloarthritis compared to healthy controls: a technology-based approach

Introduction

Traditionally, assessment in axial Spondyloarthritis (aSpA) includes the evaluation of the capacity to execute tasks, conceptualized as physical function. The role of physical activity, defined as movement-related energy expenditure, is largely unknown and almost exclusively studied using patient-reported outcome measures. The aims of this observational cross-sectional study are to compare physical activity between patients with aSpA and healthy controls (HC) and to evaluate the contribution of disease activity to physical activity differences between groups.

Methods

Forty patients with aSpA were matched by age, gender, period of data acquisition in terms of days and season to 40 HC. Physical activity was measured during five consecutive days (three weekdays and two weekend days) using ambulatory monitoring (SenseWear Armband). Self-reported disease activity was measured by the Bath Ankylosing Spondylitis Disease Activity Index (BASDAI). Differences in physical activity between patients with aSpA and HC were examined with Wilcoxon signed-rank tests and a mixed linear model. Difference scores between patients and HC were correlated with disease activity.

Results

Average weekly physical activity level (Med(IQR); HC:1.54(1.41–1.73); aSpA:1.45(1.31–1.67),MET) and energy expenditure (HC:36.40(33.43–41.01); aSpA:34.55(31.08–39.41),MET.hrs/day) were significantly lower in patients with aSpA. Analyses across intensity levels revealed no significant differences between groups for inactivity and time spent at light or moderate physical activities. In contrast, weekly averages of vigorous (HC:4.02(1.20–12.60); aSpA:0.00(0.00–1.20),min/d), very vigorous physical activities (HC0.00(0.00–1.08); aSpA:0.00(0.00–0.00),mind/d) and moderate/(very)vigorous combined (HC2.41(1.62–3.48); aSpA:1.63(1.20–2.82),hrs/d) were significantly lower in patients with aSpA. Disease activity did not interact with differences in physical activity between patients with aSpA and HC, evidenced by non-significant and very low correlations (range: −0.06–0.17) between BASDAI and HC-aSpA patients' difference scores.

Conclusions

Patients with aSpA exhibit lower physical activity compared to HC and these differences are independent of self-reported disease activity. Further research on PA in patients with aSpA should be prioritized.

Serum adipokines and adipose tissue distribution in rheumatoid arthritis and ankylosing spondylitis. A comparative study

Rheumatoid arthritis (RA) and ankylosing spondylitis (AS) are inflammatory rheumatic diseases that may modify body composition. Adipose tissue has the ability to release a wide range of products involved in physiologic functions, but also in various pathological processes, including the inflammatory/immune response. RA and AS are both associated with the development of cardiovascular complications. It is has been established that central/abdominal, and particularly intra-abdominal or visceral adiposity is closely linked to cardiovascular events. Thus, in this study, we aimed to evaluate the body composition of patients with RA or AS compared to healthy controls (HC), with a special emphasis on the visceral region. In parallel, we measured adipose products or adipokines, namely leptin, adiponectin and its high molecular weight (HMW) isoform, resistin, and ghrelin, a gastric peptide that plays a role in energetic balance. The homeostasis model assessment for insulin resistance (HOMA-IR) and atherogenic index were used to evaluate cardiovascular risk. One hundred and twelve subjects were enrolled (30 patients with RA, 31 with AS, and 51 HC). Body composition was measured using dual-energy X-ray absorptiometry to determine total fat mass and lean mass, adiposity, fat in the android and gynoid regions, and visceral fat. Patients and HC did not differ in terms of body mass index. On the contrary, adiposity was increased in RA (p = 0.01) while visceral fat was also increased, but only in women (p = 0.01). Patients with AS tended to have lower total fat mass (p = 0.07) and higher lean mass compared to HC (p = 0.07). Leptin and leptin/fat mass were decreased in male patients with AS (p < 0.01), while total adiponectin and the ratio of HMW to total adiponectin were both increased in RA (p < 0.01). There were no changes in serum resistin and ghrelin in any group of patients. HOMA-IR and the atherogenic index were not modified in RA and AS. These results confirm that body composition was altered in RA and AS, affecting distinct soft tissue compartments. The effect of the increased visceral adipose tissue on cardiovascular risk is presumably attenuated by the favorable cardiometabolic profile in women with RA, as suggested by the normal HOMA-IR and atherogenic index.

Daily physical activity in ankylosing spondylitis: validity and reliability of the IPAQ and SQUASH and the relation with clinical assessments

Introduction

The aim of this study was to investigate the construct validity and test-retest reliability of the International Physical Activity Questionnaire (IPAQ; long form) and the Short QUestionnaire to Assess Health-enhancing physical activity (SQUASH) and to investigate the relation between daily physical activity and clinical assessments in patients with ankylosing spondylitis (AS).

Methods

For validity, the self-report questionnaires IPAQ and SQUASH were compared with daily physical activity assessed with the ActiGraph accelerometer during 7 consecutive days in 63 AS outpatients. For reliability, the IPAQ and SQUASH were administered twice approximately 1 week apart in 52 AS outpatients. In all 115 patients, clinical assessments were performed at the outpatient clinic.

Results

IPAQ and SQUASH total scores correlated significantly with accelerometer outcome: ρ = 0.38 and r = 0.35, respectively. Intraclass correlation coefficients between first and second assessments of the IPAQ and SQUASH were 0.83 and 0.89, respectively. Bland-Altman analyses showed no systemic bias, but in particular for the IPAQ the 95% limits of agreement were wide. Daily physical activity assessed by accelerometer, IPAQ, and SQUASH correlated significantly with disease activity, physical activity, and quality of life. A relation with spinal mobility was found only for the accelerometer and SQUASH. The direction of these correlations indicates that higher daily physical activity is related to lower disease activity and better physical function, spinal mobility and quality of life.

Conclusions

Both physical activity questionnaires showed modest construct validity. The SQUASH showed good test-retest reliability, superior to the IPAQ. These results indicate that the SQUASH is more suitable than the IPAQ to assess daily physical activity in AS population studies. However, it is desirable to add questions on AS-specific physical activity. Further studies are needed to investigate the causality of the relation between daily physical activity and clinical assessments.

Cardiorespiratory fitness and cardiovascular risk in patients with ankylosing spondylitis: a cross-sectional comparative study

OBJECTIVE

To investigate the associations between cardiorespiratory fitness (CRF) and the level of cardiovascular (CV) risk factors in patients with ankylosing spondylitis (AS) and controls.

METHODS

In a cross-sectional comparative study, CRF was measured with a maximal treadmill test for estimation of peak oxygen uptake. Metabolic syndrome (MS), body composition, traditional CV risk factors, and inflammatory markers were assessed. Multivariable linear regression models were used to study the associations between CRF and CV risk factors. All models were adjusted for age, sex, and smoking, and for inflammation when C-reactive protein (CRP) level or erythrocyte sedimentation rate (ESR) were not already included as dependent variables.

RESULTS

A total of 126 patients (mean ± SD age 47.9 ± 10.8 years) and 111 controls (mean ± SD age 52.1 ± 11.1 years) were included. There were significant inverse associations between CRF and body mass index, waist circumference, triglycerides, CRP level, and ESR (P < 0.001-0.03) for patients and controls. Also, significant associations were found between CRF and high-density lipoprotein (HDL) cholesterol (β = 0.03, P < 0.001) and blood pressure (BP; β = -0.9 for systolic and β = -0.6 for diastolic; P < 0.01) in controls, but these associations were not found in patients (β = 0, P = 0.69 for HDL cholesterol; β = -0.04, P = 0.87 for systolic pressure; and β = -0.14, P = 0.34 for diastolic pressure) (additional adjustments for medication). Higher CRF was associated with a lower risk for MS in both patients (odds ratio [OR] 0.91, P = 0.03) and controls (OR 0.89, P = 0.01).

CONCLUSION

CRF was associated with favorable levels of CV risk factors and lower risk of MS in both AS patients and controls. However, established findings of an association between CRF and BP and HDL cholesterol in healthy adults were not confirmed in AS patients.