Level of Activities Associated With Mobility During Everyday Life in Patients With Chronic Congestive Heart Failure as Measured With an "Activity Monitor"

Real-World Gait Detection Using a Wrist-Worn Inertial Sensor: Validation Study

BACKGROUND

Wrist-worn inertial sensors are used in digital health for evaluating mobility in real-world environments. Preceding the estimation of spatiotemporal gait parameters within long-term recordings, gait detection is an important step to identify regions of interest where gait occurs, which requires robust algorithms due to the complexity of arm movements. While algorithms exist for other sensor positions, a comparative validation of algorithms applied to the wrist position on real-world data sets across different disease populations is missing. Furthermore, gait detection performance differences between the wrist and lower back position have not yet been explored but could yield valuable information regarding sensor position choice in clinical studies.

OBJECTIVE

The aim of this study was to validate gait sequence (GS) detection algorithms developed for the wrist position against reference data acquired in a real-world context. In addition, this study aimed to compare the performance of algorithms applied to the wrist position to those applied to lower back-worn inertial sensors.

METHODS

Participants with Parkinson disease, multiple sclerosis, proximal femoral fracture (hip fracture recovery), chronic obstructive pulmonary disease, and congestive heart failure and healthy older adults (N=83) were monitored for 2.5 hours in the real-world using inertial sensors on the wrist, lower back, and feet including pressure insoles and infrared distance sensors as reference. In total, 10 algorithms for wrist-based gait detection were validated against a multisensor reference system and compared to gait detection performance using lower back-worn inertial sensors.

RESULTS

The best-performing GS detection algorithm for the wrist showed a mean (per disease group) sensitivity ranging between 0.55 (SD 0.29) and 0.81 (SD 0.09) and a mean (per disease group) specificity ranging between 0.95 (SD 0.06) and 0.98 (SD 0.02). The mean relative absolute error of estimated walking time ranged between 8.9% (SD 7.1%) and 32.7% (SD 19.2%) per disease group for this algorithm as compared to the reference system. Gait detection performance from the best algorithm applied to the wrist inertial sensors was lower than for the best algorithms applied to the lower back, which yielded mean sensitivity between 0.71 (SD 0.12) and 0.91 (SD 0.04), mean specificity between 0.96 (SD 0.03) and 0.99 (SD 0.01), and a mean relative absolute error of estimated walking time between 6.3% (SD 5.4%) and 23.5% (SD 13%). Performance was lower in disease groups with major gait impairments (eg, patients recovering from hip fracture) and for patients using bilateral walking aids.

CONCLUSIONS

Algorithms applied to the wrist position can detect GSs with high performance in real-world environments. Those periods of interest in real-world recordings can facilitate gait parameter extraction and allow the quantification of gait duration distribution in everyday life. Our findings allow taking informed decisions on alternative positions for gait recording in clinical studies and public health.

TRIAL REGISTRATION

ISRCTN Registry 12246987; https://www.isrctn.com/ISRCTN12246987.

INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID)

RR2-10.1136/bmjopen-2021-050785.

Effects of seat height on whole-body movement and lower limb muscle power during sit-to-stand movements in young and older individuals

Sit-to-stand (STS) movements from low seat height are not easily executed by older individuals. Although young individuals increase their lower limb muscle power (LLMP) based on the product of the ground reaction force (GRF) and center of mass velocity (CoMv) during STS movement from a low seat height, it remains unclear whether seat height has an effect on LLMP during STS movement in older individuals. The present study aimed to investigate differences in the LLMP during STS movements when seat height is lowered between young and older individuals. Twelve older and twelve height-matched young individuals were instructed to perform STS movements from low (20 cm), middle (40 cm), and high (60 cm) seat heights. STS movement and GRF were obtained by a motion analysis system and force plates. In the low-seat-height condition, the forward and upward LLMPs and the upward CoMv were significantly lower in older individuals than those in young individuals, but the forward CoMv was not. The completion time of STS movement from a low seat height was significantly longer in older individuals than in young individuals. Our findings suggest that the slower upward CoMv due to the lower upward LLMP extends the completion time of STS movement from a low seat height in older individuals. Furthermore, in the low-seat-height condition, older individuals may move their center of mass (CoM) forward in a different way when compared with young individuals, and they may not use forward LLMP for moving CoM forward.

Consensus based framework for digital mobility monitoring

Digital mobility assessment using wearable sensor systems has the potential to capture walking performance in a patient's natural environment. It enables monitoring of health status and disease progression and evaluation of interventions in real-world situations. In contrast to laboratory settings, real-world walking occurs in non-conventional environments and under unconstrained and uncontrolled conditions. Despite the general understanding, there is a lack of agreed definitions about what constitutes real-world walking, impeding the comparison and interpretation of the acquired data across systems and studies. The goal of this study was to obtain expert-based consensus on specific aspects of real-world walking and to provide respective definitions in a common terminological framework. An adapted Delphi method was used to obtain agreed definitions related to real-world walking. In an online survey, 162 participants from a panel of academic, clinical and industrial experts with experience in the field of gait analysis were asked for agreement on previously specified definitions. Descriptive statistics was used to evaluate whether consent (> 75% agreement as defined a priori) was reached. Of 162 experts invited to participate, 51 completed all rounds (31.5% response rate). We obtained consensus on all definitions ("Walking" > 90%, "Purposeful" > 75%, "Real-world" > 90%, "Walking bout" > 80%, "Walking speed" > 75%, "Turning" > 90% agreement) after two rounds. The identification of a consented set of real-world walking definitions has important implications for the development of assessment and analysis protocols, as well as for the reporting and comparison of digital mobility outcomes across studies and systems. The definitions will serve as a common framework for implementing digital and mobile technologies for gait assessment and are an important link for the transition from supervised to unsupervised gait assessment.

Self-reported and objectively measured physical activity in people with and without chronic heart failure: UK Biobank analysis

Objective

The impact of heart failure (HF) on perceived and objectively measured levels of physical activity (PA) can inform risk stratification and treatment recommendation. We aimed to compare self-reported and objectively measured PA levels in a large sample of participants with and without HF.

Methods

A validated PA questionnaire was used to estimate self-reported weekly PA among 1600 participants with HF and 387 580 participants without HF. Accelerometer data were studied in 596 participants with HF and 96 105 participants without HF for a period of 7 days. Using multivariable linear regression models, we compared the PA levels between participants with HF and without HF, focusing on both the average daily PA levels and the intensity of PAs throughout the day.

Results

PA levels were significantly lower in participants with HF using both self-report (excess metabolic equivalent of task hours per week of 26.5 (95% CI 24.7 to 28.4) vs 34.7 (95% CI 34.5 to 34.9), respectively (p<0.001)) and accelerometer measures (mean accelerations of 23.7 milligravity (95% CI 23.1 to 24.4) vs 28.1 milligravity (95% CI 28.0 to 28.1), respectively (p<0.001)). Findings were consistent across different PA intensities. Hour-by-hour comparisons showed that accelerometer-derived PA levels of patients with HF were reduced throughout the day.

Conclusion

Perceived and objectively recorded PA levels of patients with chronic HF are significantly lower than those of individuals without HF. This difference is continuous throughout the different hours of the day, with individuals with HF being on average 16% less active than individuals without HF. In patients with HF, increases in everyday activity may be a potential alternative to structured exercise programmes.

Usefulness of Modern Activity Trackers for Monitoring Exercise Behavior in Chronic Cardiac Patients: Validation Study

BACKGROUND

Improving physical activity (PA) is a core component of secondary prevention and cardiac (tele)rehabilitation. Commercially available activity trackers are frequently used to monitor and promote PA in cardiac patients. However, studies on the validity of these devices in cardiac patients are scarce. As cardiac patients are being advised and treated based on PA parameters measured by these devices, it is highly important to evaluate the accuracy of these parameters in this specific population.

OBJECTIVE

The aim of this study was to determine the accuracy and responsiveness of 2 wrist-worn activity trackers, Fitbit Charge 2 (FC2) and Mio Slice (MS), for the assessment of energy expenditure (EE) in cardiac patients.

METHODS

EE assessed by the activity trackers was compared with indirect calorimetry (Oxycon Mobile [OM]) during a laboratory activity protocol. Two groups were assessed: patients with stable coronary artery disease (CAD) with preserved left ventricular ejection fraction (LVEF) and patients with heart failure with reduced ejection fraction (HFrEF).

RESULTS

A total of 38 patients were included: 19 with CAD and 19 with HFrEF (LVEF 31.8%, SD 7.6%). The CAD group showed no significant difference in total EE between FC2 and OM (47.5 kcal, SD 112 kcal; P=.09), in contrast to a significant difference between MS and OM (88 kcal, SD 108 kcal; P=.003). The HFrEF group showed significant differences in EE between FC2 and OM (38 kcal, SD 57 kcal; P=.01), as well as between MS and OM (106 kcal, SD 167 kcal; P=.02). Agreement of the activity trackers was low in both groups (CAD: intraclass correlation coefficient [ICC] FC2=0.10, ICC MS=0.12; HFrEF: ICC FC2=0.42, ICC MS=0.11). The responsiveness of FC2 was poor, whereas MS was able to detect changes in cycling loads only.

CONCLUSIONS

Both activity trackers demonstrated low accuracy in estimating EE in cardiac patients and poor performance to detect within-patient changes in the low-to-moderate exercise intensity domain. Although the use of activity trackers in cardiac patients is promising and could enhance daily exercise behavior, these findings highlight the need for population-specific devices and algorithms.

Accelerometer-Measured Daily Activity Levels and Related Factors in Patients With Heart Failure

BACKGROUND

Few studies report objective accelerometer-measured daily physical activity levels in patients with heart failure (HF).

OBJECTIVE

We examined baseline accelerometer-measured physical activity from the Heart Failure Exercise and Resistance Training Camp trial, a federally funded (R01-HL112979) 18-month intervention study to promote adherence to exercise in patients with HF. Factors associated with physical activity levels were also explored.

METHODS

Patients with diagnosed HF (stage C chronic HF confirmed by echocardiography and clinical evaluation) were recruited from 2 urban medical centers. Physical activity energy expenditure and the number of minutes of moderate or vigorous physical activity (MVPA) were obtained from 7 full days of measurement with the accelerometer (Actigraph Model GT3X, Pensacola, Florida) for 182 subjects who met minimum valid wear time parameters. Additional measures of health-related factors were included to explore the association with physical activity levels.

RESULTS

Subjects had 10.2 ± 10.5 minutes of MVPA per day. Total physical activity energy expenditure was 304 ± 173 kcal on average per day. There were 23 individuals (12.6%) who met the recommended goal of 150 minutes of MVPA per week. Men, whites, New York Heart Association class II, and subjects with better physical function had significantly higher levels of activity.

CONCLUSIONS

Consistent with previous research, patients with HF are not meeting recommended guidelines for 150 minutes of MVPA per week.

Long-term Physical Activity Behavior After Completion of Traditional Versus Fast-track Cardiac Rehabilitation

BACKGROUND

Despite the health benefits associated with regular physical activity (PA), many cardiac patients fail to maintain optimal levels of PA after completing cardiac rehabilitation (CR). The long-term impact of different CR delivery models on the PA habits of cardiac patients is not completely understood.

OBJECTIVE

The purpose of this study is to use a multisensor accelerometer to compare the long-term impact of a traditional versus fast-track CR on the PA of patients with coronary artery disease 6 months after CR entry.

METHODS

Forty-four participants attended either traditional (twice a week, 12 weeks; n = 24) or fast-track (once a week, 8 weeks; n = 20) CR. Exercise capacity (ie, 6-minute walk test distance) and PA were assessed at baseline and at 12 weeks and 6 months after CR entry.

RESULTS

At 12 weeks, exercise capacity increased significantly in both groups and remained elevated by the 6-month follow-up. Sedentary time decreased from baseline to 12 weeks. However, at 6 months, it was comparable with the baseline level. There was no significant change in any other PA marker (ie, steps/day, time in light and moderate-vigorous PA) over the course of the study.

CONCLUSIONS

Findings support the long-term effectiveness of CR on exercise capacity irrespective of the delivery model. However, participation in CR program, whether it be a traditional or fast-track CR exercise program, may not lead to long-term PA behavior change. Thus, CR participants may benefit from structured strategies that promote long-term PA adherence in addition to facilitating exercise capacity improvement.

Assessment of functional capacity and sleep quality of patients with chronic heart failure

Background:

Adequate sleep improves physical and mental alertness. However, there is a dearth of empirical data on functional capacity (FC) and sleep quality (SpQ) in patients with chronic heart failure (CHF).

Objective:

This study investigated the relationship between FC and SpQ of patients with CHF and apparently healthy controls (HCs).

Methods:

This case-control study recruited 50 patients with CHF whose left ventricular ejection fraction (LVEF) was <40%, attending cardiac clinics of selected government hospitals in Osun State. Furthermore, 50 age- and sex-matched healthy individuals were recruited as controls. Socio-demographic characteristics and cardiovascular parameters were assessed. The FC (VO₂ max) and SpQ were assessed using the 6-minute walk test (6-MWT) and Pittsburgh Sleep Quality Index (PSQI), respectively. Data were analysed using descriptive and inferential statistics. Alpha level was set at p < 0.05.

Results:

Patients had a significantly lower FC and poorer SpQ than HCs, 4.6 ± 0.5 versus 11.3 ± 1.6 mL/kg/min (t = −3.452; p = 0.001) and 8.74 ± 1.6 versus 3.8 ± 1.3 (t = −5.371; p = 0.001), respectively. HCs were about five times more likely to walk longer distance [odds ratio (OR), 4.8; confidence interval (CI), 2.0–11.1] and had a better heart rate (OR, 2.8; CI, 1.4–5.3) than patients. SpQ had a significant negative correlation with FC of patients (r = −0.362; p = 0.001) but a significant positive correlation with HCs (r = 0.481; p = 0.041). Furthermore, there were significant correlations between FC and body mass index in both groups (CHF: r = 0.247, p = 0.022; HCs: r = 0.321, p = 0.040).

Conclusion:

Patients with heart failure demonstrated lower functional capacity and poorer sleep quality.

Physical fitness and physical activity in fatigued and non-fatigued inflammatory bowel disease patients

OBJECTIVE

To assess physical fitness and physical activity in inflammatory bowel disease (IBD) patients and whether fatigue is associated with impaired physical fitness and impaired physical activity.

MATERIALS AND METHODS

Ten patients with quiescent IBD and fatigue (fatigue group [FG]) based on the Checklist Individual Strength-Fatigue score of ≥35 were matched for age (±5 years) and sex with a non-fatigue group (NFG) with IBD. Physical fitness was measured with a cyclo-ergometric-based maximal exercise test, a submaximal 6-min walk test, and a dynamometer test to quantify the isokinetic muscle strength of the knee extensors and flexors. Level of physical activity was measured with an accelerometer-based activity monitor.

RESULTS

The patients in both groups did not differ in regard to medication use, clinical characteristics, and body composition. However, medium-to-large effect sizes for impaired physical fitness (both cardiorespiratory fitness and muscle strength) and physical activity were seen between the patients in the FG and the NFG. Especially, intensity of physical activity was significantly lower in the FG patients compared with the NFG patients (effect size: 1.02; p = 0.037). Similar results were seen when outcomes of the FG and NFG were compared with reference values of the normal population.

CONCLUSION

Fatigued IBD patients show an impaired physical fitness and physical activity compared with non-fatigued IBD patients. This gives directions for a physical component in fatigue in IBD patients. Therefore, these new insights into fatigue indicate that these patients might benefit from an exercise program to improve physical fitness and physical activity.

Daily sit-to-stands performed by adults: a systematic review

[Purpose] The sit-to-stand (STS) maneuver is a component of everyday mobility. The purpose of this review was to summarize the number of daily STSs performed by adults with or without pathology. [Methods] Four bibliographic databases were searched followed by a consultation with experts and a search by hand to locate articles reporting daily STSs. Information on measurement procedures, tested populations, and daily STSs was extracted. Methodological quality was rated. [Results] Ten articles were identified. The mean number of daily STSs ranged from 33 to 71. The mean number was at least 45 for all groups except patients with congestive heart failure, residents of a hospital ward and one group of older adults. [Conclusion] Individuals performing fewer than 45 daily STSs may be experiencing a work deficit and benefit from additional intentional STS repetitions.

Effect of exercise training on the quality of life and echocardiography parameter of systolic function in patients with chronic heart failure: a randomized trial

Background:

Ejection fraction promotion in heart failure patients reduces mortalities and limitations.

Objectives:

This study was to investigate the effect of exercise on ejection fraction of chronic heart failure patients.

Patients and Methods:

The present study was conducted on patients with chronic heart failure. 66 patients were divided randomly into two experimental and control groups of 33 each. The subjects were male and female. The patients in experimental group followed an exercise program three sessions per week for 24 weeks. Echocardiography and quality of life questionnaire were used to gather data. The data were analyzed by SPSS 18 through pair and independent t-test.

Results:

The results indicated a significant difference in left ventricular diameter (LV-ESD, LV-EDD) and ejection fraction at the end of exercise program in experimental group and 24 weeks after in control group. There was a significant difference in quality of life in physical performance, activity limitation following physical problems, energy and fatigue, social performance, physical pain, and public health (P < 0.05 for all) between two groups.

Conclusions:

Exercise program increases ejection fraction and quality of life in chronic heart failure patients, associated with management of disease by health team.

Intrinsic skeletal muscle alterations in chronic heart failure patients: a disease-specific myopathy or a result of deconditioning?

Chronic heart failure (CHF) patients frequently experience impaired exercise tolerance due to skeletal muscle fatigue. Studies suggest that this in part is due to intrinsic alterations in skeletal muscle of CHF patients, often interpreted as a disease-specific myopathy. Knowledge about the mechanisms underlying these skeletal muscle alterations is of importance for the pathophysiological understanding of CHF, therapeutic approach and rehabilitation strategies. We here critically review the evidence for skeletal muscle alterations in CHF, the underlying mechanisms of such alterations and how skeletal muscle responds to training in this patient group. Skeletal muscle characteristics in CHF patients are very similar to what is reported in response to chronic obstructive pulmonary disease (COPD), detraining and deconditioning. Furthermore, skeletal muscle alterations observed in CHF patients are reversible by training, and skeletal muscle of CHF patients seems to be at least as trainable as that of matched controls. We argue that deconditioning is a major contributor to the skeletal muscle dysfunction in CHF patients and that further research is needed to determine whether, and to what extent, the intrinsic skeletal muscle alterations in CHF represent an integral part of the pathophysiology in this disease.

Ambient temperature and biomarkers of heart failure: a repeated measures analysis

BACKGROUND

Extreme temperatures have been associated with hospitalization and death among individuals with heart failure, but few studies have explored the underlying mechanisms.

OBJECTIVES

We hypothesized that outdoor temperature in the Boston, Massachusetts, area (1- to 4-day moving averages) would be associated with higher levels of biomarkers of inflammation and myocyte injury in a repeated-measures study of individuals with stable heart failure.

METHODS

We analyzed data from a completed clinical trial that randomized 100 patients to 12 weeks of tai chi classes or to time-matched education control. B-type natriuretic peptide (BNP), C-reactive protein (CRP), and tumor necrosis factor (TNF) were measured at baseline, 6 weeks, and 12 weeks. Endothelin-1 was measured at baseline and 12 weeks. We used fixed effects models to evaluate associations with measures of temperature that were adjusted for time-varying covariates.

RESULTS

Higher apparent temperature was associated with higher levels of BNP beginning with 2-day moving averages and reached statistical significance for 3- and 4-day moving averages. CRP results followed a similar pattern but were delayed by 1 day. A 5°C change in 3- and 4-day moving averages of apparent temperature was associated with 11.3% [95% confidence interval (CI): 1.1, 22.5; p = 0.03) and 11.4% (95% CI: 1.2, 22.5; p = 0.03) higher BNP. A 5°C change in the 4-day moving average of apparent temperature was associated with 21.6% (95% CI: 2.5, 44.2; p = 0.03) higher CRP. No clear associations with TNF or endothelin-1 were observed.

CONCLUSIONS

Among patients undergoing treatment for heart failure, we observed positive associations between temperature and both BNP and CRP-predictors of heart failure prognosis and severity.

Physical activity patterns of patients with cardiopulmonary illnesses

OBJECTIVES

The aims of this paper were (1) to describe objectively confirmed physical activity patterns across 3 chronic cardiopulmonary conditions, and (2) to examine the relationship between selected physical activity dimensions with disease severity, self-reported physical and emotional functioning, and exercise performance.

DESIGN

Cross-sectional study.

SETTING

Participants' home environment.

PARTICIPANTS

Patients with cardiopulmonary illnesses: chronic obstructive pulmonary disease (COPD) (n=63), heart failure (n=60), and patients with implantable cardioverter defibrillator (n=60).

INTERVENTIONS

Not applicable.

MAIN OUTCOME MEASURES

Seven ambulatory physical activity dimensions (total steps, percent time active, percent time ambulating at low, medium, and high intensity, maximum cadence for 30 continuous minutes, and peak performance) were measured with an accelerometer.

RESULTS

Subjects with COPD had the lowest amount of ambulatory physical activity compared with subjects with heart failure and cardiac dysrhythmias (all 7 activity dimensions, P<.05); total step counts were: 5319 versus 7464 versus 9570, respectively. Six-minute walk distance was correlated (r=.44-.65, P<.01) with all physical activity dimensions in the COPD sample, the strongest correlations being with total steps and peak performance. In subjects with cardiac impairment, maximal oxygen consumption had only small to moderate correlations with 5 of the physical activity dimensions (r=.22-.40, P<.05). In contrast, correlations between 6-minute walk test distance and physical activity were higher (r=.48-.61, P<.01) albeit in a smaller sample of only patients with heart failure. For all 3 samples, self-reported physical and mental health functioning, age, body mass index, airflow obstruction, and ejection fraction had either relatively small or nonsignificant correlations with physical activity.

CONCLUSIONS

All 7 dimensions of ambulatory physical activity discriminated between subjects with COPD, heart failure, and cardiac dysrhythmias. Depending on the research or clinical goal, use of 1 dimension, such as total steps, may be sufficient. Although physical activity had high correlations with performance on a 6-minute walk test relative to other variables, accelerometry-based physical activity monitoring provides unique, important information about real-world behavior in patients with cardiopulmonary illness not already captured with existing measures.

Upper limb activity over time in complex regional pain syndrome type 1 as objectively measured with an upper limb-activity monitor: An explorative multiple case study

BACKGROUND

An upper limb-activity monitor (ULAM) has been developed to determine activity limitations in complex regional pain syndrome type 1 (CRPS1). The ULAM is based on 24h ambulatory monitoring of body segment accelerations and enables valid and objective quantification of mobility and upper limb activity in transversal studies.

AIMS

To explore upper limb activity over time in acute upper limb CRPS1 as measured with the ULAM in a longitudinal study, and to compare this to time courses of other outcome measures for activity limitations and impairments.

METHODS

Four subjects were measured four times during a treatment protocol. Several ULAM outcome measures related to upper limb usage and mobility, three questionnaires (RASQ, DASH, RAND36), and six impairment outcome indicators (VAS-momentary pain, VAS-pain resulting from effort, volume, temperature, active range of motion, strength) were used.

RESULTS

Objectively measured upper limb activity frequently improved; improvements of >5% were found for 63% of the ULAM outcome measures at final assessment. The ULAM outcome measures had a time course more similar to the body-part and CRPS1 specific questionnaire RASQ than the other questionnaires. The time course of impaired temperature was most often in accordance with the ULAM, and both VAS scores showed least accordance.

CONCLUSIONS

Clear changes in upper limb activity over time were frequently found as objectively measured with the ULAM, and relationships among the time courses of the ULAM and other outcome measures were largely explainable. The ULAM can validly assess upper limb activity over time in CRPS1, but between-measurement variability needs careful consideration.

Daily and hourly frequency of the sit to stand movement in older adults: a comparison of day hospital, rehabilitation ward and community living groups

BACKGROUND AND AIMS

The sit to stand (STS) movement is commonly performed in daily life, and can be used as an indicator of activity. This study aimed to quantify the usual frequency and distribution of the STS movement performed by older adults in both home and rehabilitation settings.

METHODS

Three groups of older adults were recruited; healthy older adults living in the community, older adults living in the community attending rehabilitation services at a day hospital, and frail older patients in a rehabilitation ward. Participants wore an activity monitor, which reported posture continuously for a week. The number of STS movements was the primary outcome measure, and mean values of daily STS frequency were reported. The pattern of activity was investigated using median values of STS hourly rate.

RESULTS

Healthy older adults living in the community performed significantly more STS movements per day (n=20; 71±25) than either older adults attending a day hospital (n=20; 57±23) or frail older patients in a rehabilitation ward (n=30; 36±16). For all participants, the hourly rate of STS movements ranged from zero to 48, although the median hourly rate was two (healthy older adults) and one (both rehabilitation groups).

CONCLUSION

Measurement of the number of STS movements performed over the course of a week in three groups of older adults, demonstrated significant differences in daily number of STS movements and in the hourly pattern between the groups. Activity patterns can provide additional information on clinically relevant aspects of physical activity and function to daily averages.

Evidence-based risk assessment and recommendations for physical activity clearance: established cardiovascular disease1This paper is one of a selection of papers published in this Special Issue, entitled Evidence-based risk assessment and recommendations for physical activity clearance, and has undergone the Journal’s usual peer review process

Physical activity is an effective lifestyle therapy for patients at risk for, or with, documented cardiovascular disease (CVD). Current screening tools — the Physical Activity Readiness Questionnaire (PAR-Q) and the Physical Activity Readiness Medical Evaluation (PARmed-X) — require updating to align with risk/benefit evidence. We provide evidence-based recommendations to identify individuals with CVD at lower risk, intermediate risk, or higher risk of adverse events when participating in physical activity. Forms of exercise and the settings that will appropriately manage the risks are identified. A computer-assisted search of electronic databases, using search terms for CVD and physical activity risks and benefits, was employed. The Appraisal of Guidelines for Research and Evaluation were applied to assess the evidence and assign a strength of evidence rating. A strength rating for the physical activity participation clearance recommendation was assigned on the basis of the evidence. Recommendations for physical activity clearance were made for specific CVD groups. Evidence indicates that those who are medically stable, who are involved with physical activity, and who have adequate physical ability can participate in physical activity of lower to moderate risk. Patients at higher risk can exercise in medically supervised programs. Systematic evaluation of evidence indicates that clinically stable individuals with CVD may participate in physical activity with little risk of adverse events. Therefore, changes in the PAR-Q should be undertaken and a process of assessment and consultation to replace the PARmed-X should be developed. Patients at lower risk may exercise at low to moderate intensities with minimal supervision. Those at intermediate risk should exercise with guidance from a qualified exercise professional. Patients at higher risk should exercise in medically supervised programs.

Validation of the Physical Activity Scale for individuals with physical disabilities

OBJECTIVE

To determine the criterion validity of the Physical Activity Scale for Individuals With Physical Disabilities (PASIPD) by means of daily physical activity levels measured by using a validated accelerometry-based activity monitor in a large group of persons with a physical disability.

DESIGN

Cross-sectional.

SETTING

Participants' home environment.

PARTICIPANTS

Ambulatory and nonambulatory persons with cerebral palsy, meningomyelocele, or spinal cord injury (N=124).

INTERVENTIONS

Not applicable.

MAIN OUTCOME MEASURES

Self-reported physical activity level measured by using the PASIPD, a 2-day recall questionnaire, was correlated to objectively measured physical activity level measured by using a validated accelerometry-based activity monitor.

RESULTS

Significant Spearman correlation coefficients between the PASIPD and activity monitor outcome measures ranged from .22 to .37. The PASIPD overestimated the duration of physical activity measured by using the activity monitor (mean ± SD, 3.9±2.9 vs 1.5±0.9h/d; P<.01). Significant correlation (ρ=-.74; P<.01) was found between average number of hours of physical activity per day measured by using the 2 methods and difference in hours between methods. This indicates larger overestimation for persons with higher activity levels.

CONCLUSIONS

The PASIPD correlated poorly with objective measurements using an accelerometry-based activity monitor in people with a physical disability. However, similar low correlations between objective and subjective activity measurements have been found in the general population. Users of the PASIPD should be cautious about overestimating physical activity levels.

Accelerometry-based activity spectrum in persons with chronic physical conditions

OBJECTIVES

(1) To give an overview of the impact of a variety of chronic physical conditions on accelerometry-based levels of everyday physical activity and to identify high-risk conditions; and (2) to compare these objectively assessed activity levels with the levels estimated by rehabilitation physicians.

INTERVENTIONS

Not applicable.

DESIGN

Cross-sectional study.

SETTING

Participant's home environment.

PARTICIPANTS

Patients (n=461) with 18 chronic physical (sub)conditions and able-bodied subjects (n=96).

MAIN OUTCOME MEASURES

We summarized data on the level of everyday physical activity as objectively measured with an accelerometry-based activity monitor. Thirty-one rehabilitation physicians filled in a questionnaire designed to obtain their estimates of the level of physical activity in patients with the various conditions.

RESULTS

Only 4 of the studied conditions had normal activity levels (≥90% of the able-bodied level). Persons with transtibial amputation (vascular), spinal cord injury, and myelomeningocele (wheelchair dependent) had the lowest levels of activity, less than 40% of the able-bodied level. In general, rehabilitation physicians were aware of the inactive lifestyles, but considerably underestimated the magnitude of inactivity in the high-risk conditions.

CONCLUSIONS

This is the first study to provide an objectively assessed activity spectrum in a variety of chronic physical conditions. We hope this study will increase the awareness of health professionals as to which chronic physical conditions are at increased risk for an inactive lifestyle, and will contribute to adaptation of patient management accordingly.

Everyday physical activity and community participation of adults with hemiplegic Cerebral Palsy

PURPOSE

To assess the level and potential determinants of everyday physical activity and participation in various life areas of adults with hemiplegic cerebral palsy (CP) in comparison with healthy subjects.

METHOD

In a cross-sectional study everyday physical activity was measured (Activity Monitor) in 16 adults with CP, aged 28 (3) years, and 16 age/gender matched healthy volunteers, aged 29 (3) years. Participation was assessed by means of validated questionnaires. Age, gender, body fat (skinfold thickness), muscle tone (Ashworth Scale), functional level and participation were assessed as potential determinants of everyday physical activity.

RESULTS

In adults with CP mean (SD) duration of dynamic activities during a day (10.6 [3.5]%) was comparable to healthy subjects (11.2 4%) (p = 0.66). In most life areas the level of participation was comparable for both groups, although adults with CP spent more time on non-intensive leisure activities. Participation in sports appeared to be a determinant of everyday physical activity in both groups.

CONCLUSIONS

The results indicate that the levels of everyday physical activity and community participation in adults with hemiplegic CP are comparable to levels in healthy comparison subjects.

Accelerometer-based quantification of 6-minute walk test performance in patients with chronic heart failure: applicability in telemedicine

BACKGROUND

Distance walked in the 6-minute walk test (6MWT) is an important prognostic parameter used clinically to assess functional status in patients with chronic heart failure (CHF). In this study, we investigated if alternative performance parameters with similar prognostic value can be gained from accelerometers.

METHODS AND RESULTS

Fifty CHF patients (age, 60.9 +/- 14.0 years) were asked to perform a 6MWT while wearing 2 accelerometers and 1 pedometer. Total 6MWT step frequency (SF) and activity counts (VMU) were correlated to 6MWT distance. The accelerometer was highly accurate at quantifying SF (detected vs. observed: r = 0.99; P < .001), whereas the pedometer was unreliable below 50 m/min. VMU increased linearly with walking speed (r = 0.99), and both SF and VMU correlated strongly with 6MWT distance (VMU: r = 0.91; SF: r = 0.87, respectively; P < .001) and each other (r = 0.80, P < .001).

CONCLUSIONS

Accelerometers are reliable in measuring physical performance during the 6MWT in CHF patients. Besides the simple acquisition of 6MWT distance currently used for patient assessment, accelerometers provide new data that might be useful to evaluate exercise performance during the 6MWT. This allows for routine assessment of exercise capacity in a home-based setting in the context of telemedicine.

A prospective study on physical activity levels after spinal cord injury during inpatient rehabilitation and the year after discharge

OBJECTIVES

To assess the change over time in the physical activity level after a spinal cord injury (SCI), to explore its determinants, and to compare the physical activity level 1 year after discharge from the rehabilitation center with the level in able-bodied persons.

DESIGN

Prospective cohort study. Measurements were obtained at the start of active rehabilitation, 3 months later, at discharge, 2 months after discharge, and 1 year after discharge.

SETTING

Rehabilitation center in The Netherlands and the participant's home.

PARTICIPANTS

Persons (n=40) with SCI.

INTERVENTIONS

Not applicable.

MAIN OUTCOME MEASURES

The physical activity level, as indicated by the duration of dynamic activities (ie, wheelchair driving, walking, cycling, noncyclic movement) per day, and the intensity of everyday activity; both were measured with an accelerometry-based activity monitor during 2 consecutive weekdays.

RESULTS

Random coefficient analyses showed that the duration of dynamic activities and the intensity of everyday activity increased during inpatient rehabilitation at rates of 41% and 19%, respectively (P<.01). Shortly after discharge, there was a strong decline (33%; P<.001) in the duration of dynamic activities. One year after discharge, this decline was restored to the discharge level but was low in comparison with levels in able-bodied persons. The level of lesion and completeness of lesion were determinants of the change in the physical activity level after discharge.

CONCLUSIONS

The physical activity level increased during inpatient rehabilitation, but this increase did not continue after discharge, and the level 1 year after discharge was distinctly lower than the level in able-bodied persons. Subpopulations had a different change over time in the physical activity level after discharge.

Everyday physical activity and adiposity in Prader-Willi syndrome

The aim of this study was to assess the impact of Prader-Willi syndrome (PWS) on the level of everyday physical activity and to explore whether the activity level is related to adiposity. Measurements were performed with an accelerometry-based Activity Monitor during two consecutive schooldays in 12 children with PWS (7-16 years of age) and in 12 age- and gender-matched, healthy children. Adiposity was assessed by body mass index standard deviation scores and by percentage body fat (dual energy X-ray absorptiometry). Mean duration of dynamic activities (expressed as percentage of 24 h) was lower in children with PWS than in the comparison group (8.7 [2.5]% and 12.0 [3.1]%, respectively; p = 0.01). Six children with PWS had normal activity levels. Physical activity level was not related to adiposity. The results indicate that, as a group, children with PWS have an inactive lifestyle. However, children with PWS cannot be stereotyped as inactive since half of them had normal activity levels.

Therapeutic implications of implantable device-based monitoring of patients with heart failure

Heart failure is one of the most common medical problems faced by patients and clinicians. It has the potential for high morbidity and mortality, and its overall financial cost to society is enormous. Management of heart failure is often difficult and time consuming, and is sometimes frustrating. The usual signs and symptoms of heart failure may not be obvious early in an exacerbation, which has prompted the development of other methods to identify early and subtle clinical changes to initiate early intervention. Current implantable devices, such as defibrillators and pacemakers, can monitor changes in heart rate and heart rate variability, patient activity, arrhythmia frequency, and thoracic impedance, all of which may be markers of clinical decline. Newer implantable devices can also measure right ventricular pressures, oxygen saturation, and pulmonary artery pressures. Many of these technologies have been shown to be feasible and potentially helpful, but outcomes data showing reductions in morbidity and mortality are currently limited. Importantly, none of these newer technologies should be used in isolation; all must be used in combination with clinical findings to provide effective disease management.

Actual everyday physical activity in patients with end-stage hip or knee osteoarthritis compared with healthy controls

OBJECTIVE

Few data are available on the level of actual physical activity in patients with osteoarthritis (OA) of the hip and knee. The aim of this study was to measure the level of actual physical activity of patients with end-stage OA of the hip and the knee, to compare this with that of matched healthy controls, and to analyze the data in order to ascertain the factors of influence.

METHOD

The actual physical activity was measured with an activity monitor (AM) in 40 hip and 44 knee OA patients, and compared with measurements obtained from healthy controls. Data were also collected on pain and psychological aspects as anxiety, depression and mental functioning. The primary outcome parameter of the actual physical activity was the percentage of movement-related activity.

RESULTS

The percentage of movement-related activity did not differ between the two OA groups. It was 8.8 (4.2)% for the hip and 8.1 (3.8)% for the knee OA patients. The matched controls were significantly higher movement-related active than OA patients (about 11.0 (2.9)%). Increasing age and body mass index were negatively associated with the percentage of movement-related activity (beta=-0.29 and beta=-0.25, respectively), whereas mental functioning was positively related (beta=0.30).

CONCLUSION

The impact of end-stage OA on the level of actual physical activity is equal for hip and knee OA patients. The actual physical activity for both of the OA groups was significantly and clinically relevantly lower compared to controls. However, this difference was smaller than expected and less dominant than patients' perception of limitations in daily life. Clinicians must be aware that the patients' perception of physical functioning in daily life does not always correspond to the actual physical activity.

Comparison of the performance of the activPAL™ Professional physical activity logger to a discrete accelerometer-based activity monitor

The aim of this study was to assess the accuracy of the 'activPAL Professional' physical activity logger by comparing its output to that of a proven discrete accelerometer-based activity monitor during extended measurements on healthy subjects while performing activities of daily living (ADL). Ten healthy adults, with unrestricted mobility, wore both the activPAL and the discrete dual accelerometer (Analog Devices ADXL202)-based activity monitor that recorded in synchronization with each other. The accelerometer derived data were then compared to that generated by the activPAL and a complete statistical and error analysis was performed using a Matlab program. This program determined trunk and thigh inclination angles to distinguish between sitting/lying, standing and stepping for the discrete accelerometer device and amount of time spent on each activity. Analysis was performed on a second-by-second basis and then categorized at 15s intervals in direct comparison with the activPAL generated data. Of the total time monitored (approximately 60 h) the detection accuracies for static and dynamic activities were approximately 98%. In a population of healthy adults, the data obtained from the activPAL Professional physical activity logger for both static and dynamic activities showed a close match to a proven discrete accelerometer data with an offset of approximately 2% between the two systems.

Impact of chronic pain on everyday physical activity

Although patients with chronic pain are often considered to have reduced levels of everyday physical activity, data on their activity levels are scarce and inconclusive. Therefore, this study explored whether patients with chronic pain have reduced activity levels, as objectively measured with an activity monitor. The activity monitor is based on long-term ambulatory monitoring of signals from body-fixed accelerometers during everyday life, aimed at assessment of mobility-related activities. Measurements with the monitor were performed during a weekday (24 h) in 18 patients with chronic pain and compared with measurements obtained from 18 gender and age matched healthy comparison subjects. The mean (SD) age of the patients was 44 (11) years, and the mean (SD) duration of their complaints was 8 (7) years. Compared with the healthy subjects, the duration of dynamic activities was not significantly reduced (p=0.10) in the patient group. Mean (SD) intensity of everyday physical activity was lower (p=0.03) in the patients than in the healthy comparison subjects (0.021 [0.006] g versus 0.026 [0.004] g), and patients spent more time lying down (47.0 [10.2]% versus 34.3 [5.6] %; p=0.000) and less time sitting (29.2 [8.9]% versus 36.4 [9.3]%; p=0.03) than the healthy comparison subjects. In spite of significant differences between patients and healthy comparison subjects for some aspects of the activity pattern (which may reflect pain behaviour), the impact of chronic pain on everyday physical activity was relatively small.

Évaluation des capacités et des performances: contribution des monitorages de la locomotion en situation d'exercice et de vie réelle

OBJECTIVES

To determine the value of ambulatory monitoring in assessing human gait. To describe the sensors, the parameters and the ambulatory devices.

MATERIALS AND METHODS

Literature review and practical experience about techniques, principles, objectives and limits.

RESULTS

Accelerometry is the main technique for ambulatory monitoring because of its reliability, pertinence of signals and software developed for interpretation. Simultaneous monitoring of heart rate response is clinically relevant. Pedometers and actimeters can answer precise clinical questions about amount of walking activity.

CONCLUSION

Ambulatory monitoring during long periods (one day or more) is important, especially for rehabilitation medicine because it measures the actual patient activity performed and participation. The simultaneous monitoring of environmental conditions of activity should improve the interpretation of the data collected.

Test-retest reliability of 24 hours of activity monitoring in individuals with Parkinson's disease in home and community

BACKGROUND/OBJECTIVE

This study examined the test-retest reliability of an activity monitor (AM) in home and community settings in individuals with Parkinson's disease (PD).

METHODS

Nine independent community dwellers with idiopathic PD were recruited (8 males and 1 female; median age = 66 years, range 46-71; Hoehn & Yahr score 2). Patients wore the AM for 3 separate sessions in the home and community with 7 days between each session. The first 2 sessions lasted 24 hours each, and the third session lasted 48 hours. Reliability indices and measures of variability were obtained by using intraclass correlation coefficients (ICC) and generalizability coefficients. The functional activity measures included the percentage of time spent in sleeping positions, sitting, standing, and walking; the number of transitions between sit and stand; the total number of transitions; the number of walking periods lasting 5 and 10 seconds; and stride frequency.

RESULTS

The ICCs for functional activities between the first and second consecutive days for the 48-hour session (third session) ranged from .76 to .92. The ICCs for the 7- and 14-day intervals ranged from .45 to .96, with walking-related measures showing the highest ICCs (range = .81 to .96). Across the three 24-hour periods (sessions 1 and 2, and the first 24 hours of session 3), the ICCs for walking-related measures were again high ranging from .87 to .92. Walking-related measures demonstrated the highest generalizability coefficients, indicating these measures have the highest test-retest reliability in comparison to other functional activity measures.

CONCLUSIONS

The present study shows that 24 hours of recording with an AM is a sufficient duration of time to reliably record patients' functional activity in the home and community settings. In addition, the highest test-retest reliability for activities across 7- and 14-day intervals were found for walking-related measures in individuals with PD, indicating these measures have the highest stability compared to the other measures of functional activity.

Monitoring Activity in Individuals with Parkinson Disease

This study was conducted to investigate the validity of an Activity Monitor (AM) recording functional activities in individuals with Parkinson disease (PD). A series of tasks were performed in both a fixed and a random manner by 11 participants with PD (H & Y 2-3; age range 40-79 years). Participants, wearing an AM, were recorded for video analysis (VA). The strength of association (rs) between the AM and VA for duration of time in body positions, walking, and bicycling across both fixed and random modules ranged from 0.63 to 0.98, however, the AM reported significantly greater time spent in body positions in both modules. Kappa statistics (K) between the AM and VA were the highest for transitions in the fixed module with Ks ranging from 0.74 to 1.0. During the random module, the agreement between the AM and VA was lowest for transitions between sitting and standing. In general, the Ks were low for activities lasting less than 5 seconds. The data collected in the study support the conclusion that the AM accurately evaluated the duration of time spent in body positions, the number of transitions between body positions, and the duration of time spent walking for activities lasting longer than 5 seconds in individuals with PD.

FATIGUE, LEVEL OF EVERYDAY PHYSICAL ACTIVITY AND QUALITY OF LIFE AFTER LIVER TRANSPLANTATION

OBJECTIVE

To assess whether liver transplant recipients have a hypoactive (sedentary) lifestyle and whether the level of everyday physical activity is related to complaints of fatigue. In addition, we explored the relationship between activity level and health-related quality of life.

DESIGN

Case comparison.

SUBJECTS

Eight persons 6-36 months after liver transplantation with varying severity of fatigue and 8 persons without known impairments (matched for gender, age, social situation and employment).

METHODS

Activity levels were assessed during 2 randomly selected consecutive weekdays with an accelerometry-based Activity Monitor. In the transplantation group, severity of fatigue (Fatigue Severity Scale) and health-related quality of life (RAND-36) were also assessed.

RESULTS

Five liver transplant recipients had a hypoactive lifestyle, but there was no significant difference in activity level between the transplantation group and comparison group. Severity of fatigue was correlated (p=0.01) with both duration of dynamic activities and intensity of everyday activity (r(s)=-0.81 and -0.84, respectively). Activity level was correlated (p< or =0.05) with several domains of health-related quality of life (r(s)=0.72-0.78).

CONCLUSION

As a group, liver transplant recipients were not significantly less active than comparison subjects. Activity level was related with severity of fatigue and health-related quality of life. These findings have implications for the development of interventions needed to rehabilitate persons after liver transplantation.

Walking in postpoliomyelitis syndrome: the relationships between time-scored tests, walking in daily life and perceived mobility problems

OBJECTIVE

To compare walking test results with walking in daily life, and to investigate the relationships between walking tests, walking activity in daily life, and perceived mobility problems in patients with post-poliomyelitis syndrome.

SUBJECTS

Twenty-four ambulant patients with post-poliomyelitis syndrome.

METHODS

Walking tests were performed at self-preferred and maximal speed. Walking activity was measured with an ambulatory activity monitor. Heart rate, step cadence and walking speed in the test and in daily life were compared. Walking speed in daily life was represented by the intensity of walking. Perceived mobility problems were assessed with the Nottingham Health Profile.

RESULTS

Heart rate during walking was lower in the test at self-preferred speed than in daily life (mean difference: 11.3+/-10.4; p=0.001). Self-preferred walking speed in the test and in daily life correlated significantly (r=0.55; p=0.04). In a sub-group with a test performance below the median value, test performance correlated significantly with walking activity. No significant correlation was found between perceived mobility problems and walking activity.

CONCLUSION

Walking in daily life may be more demanding than walking under standardized conditions. Patients with post-poliomyelitis syndrome with the lowest test performance walked less in daily life. Patients do not necessarily match their activity pattern to their perceived mobility problems.

Indices de mesure de l'activité physique dans le domaine des affections cardiovasculaires

PURPOSE

To identify the more useful among many methods available for the measurement of physical activity in patients with cardiovascular disease. For practical and financial reasons only questionnaires and mechanical monitoring, which are appropriate for use in large studies, were assessed.

METHODS

To select tools valuable for clinical and epidemiological measurement of physical activity, with sufficient validity, reproducibility and sensitivity, we reviewed the literature in Medline with use of keywords: accelerometry, ambulatory accelerometry, ambulatory monitoring, cardiovascular diseases, daily activity, heart disease, pedometer, physical activity, questionnaire.

RESULTS

Considering appropriate level of reproducibility and validity, 15 questionnaires are available. For measuring postures and motions during daily life, activity monitor seems to be more valid than pedometers or single accelerometers.

CONCLUSION

At present the preferred method is a questionnaire, provided it is valid, repeatable, easy to use and inexpensive. In the future mechanical monitoring (especially activity monitor) will be probably a good alternative.

Analysis and decomposition of accelerometric signals of trunk and thigh obtained during the sit-to-stand movement

Piezoresistive accelerometer signals are frequently used in movement analysis. However, their use and interpretation are complicated by the fact that the signal is composed of different acceleration components. The aim of the study was to obtain insight into the components of accelerometer signals from the trunk and thigh segments during four different sit-to-stand (STS) movements (self-selected, slow, fast and fullflexion). Nine subjects performed at least six trials of each type of STS movement. Accelerometer signals from the trunk and thigh in the sagittal direction were decomposed using kinematic data obtained from an opto-electronic device. Each acceleration signal was decomposed into gravitational and inertial components, and the inertial component of the trunk was subsequently decomposed into rotational and translational components. The accelerometer signals could be reliably reconstructed: mean normalised root mean square (RMS) trunk: 6.5% (range 3-12%), mean RMS thigh: 3% (range 2-5%). The accelerometric signals were highly characteristic and repeatable. The influence of the inertial component was significant, especially on the timing of the specific event of maximum trunk flexion in the accelerometer signal. The effect of inertia was larger in the trunk signal than in the thigh signal and increased with higher speeds. The study provides insight into the acceleration signal, its components and the influence of the type of STS movement and supports its use in STS movement analysis.

A randomized controlled trial comparing functional outcome and cost efficiency of a total surface-bearing socket versus a conventional patellar tendon-bearing socket in transtibial amputees

OBJECTIVE

To compare functional outcome and cost efficiency of a total surface-bearing (TSB) socket with a conventional patellar tendon-bearing (PTB) socket in transtibial amputees.

DESIGN

Prospective randomized controlled trial.

SETTING

Outpatient rehabilitation clinic of a general hospital, rehabilitation research department of a university hospital, and certified prosthetics and orthotics workplace.

PARTICIPANTS

Twenty-six adult unilateral transtibial amputees walking with a prosthesis for at least 1 year.

INTERVENTION

Subjects were randomly assigned to 2 groups: one receiving an ICEX TSB socket, the other a conventional PTB socket.

MAIN OUTCOME MEASURES

Prosthetic Evaluation Questionnaire (PEQ) score, mobility-related activities of daily life, and gait characteristics at baseline and 3 months after initial socket fitting, as well as cost of materials, manufacturing time, and number of visits and interventions.

RESULTS

No significant differences were found between both groups in terms of changes in socket function (PEQ scores, mobility-related activities, gait characteristics). In the TSB sockets, cost of materials was significantly larger, but the manufacturing time was significantly shorter and the number of visits was significantly less than in the PTB sockets.

CONCLUSIONS

Both sockets performed equally well in terms of patient satisfaction, mobility-related activities performed during daily life, and gait performance. Material costs were higher in the TSB group, whereas the manufacturing time in the TSB group was lower.

Impairments and activity limitations in subjects with chronic upper-limb complex regional pain syndrome type I

OBJECTIVE

To determine the degree of impairments and activity limitations and their interrelationship in complex regional pain syndrome type I (CRPS type I).

DESIGN

Cross-sectional study interrelating impairments and objectively measured activity limitations.

SETTING

Ambulatory and home environment.

PARTICIPANTS

Thirty nonacute upper-limb CRPS type I subjects.

INTERVENTIONS

Not applicable. Main outcome measures Sensory, motor, and autonomic impairments, as well as activity-limitation outcome measures. The latter were objectively measured with a novel upper-limb activity monitor (based on ambulatory accelerometry).

RESULTS

All subjects were impaired to some degree but with a large variability with respect to magnitude. Regarding activity limitations, the involved upper limb was clearly less active (lower intensity and percentage of activity) than the noninvolved side. Impaired active range of motion (adjusted R(2) range, 18%-39%) and grip strength (adjusted R(2) range, 12%-45%) were the most important factors explaining variance in activity limitations.

CONCLUSIONS

All subjects were still impaired nearly 3 years after the causative event. The involved upper limb was also clearly less active than the noninvolved side, especially when the subjects were sitting and when the dominant side was involved. The more impairments a subject had, especially motor impairments, the more activity limitations were present.

Interictal daily functioning in migraine

Migraine induces disability and an impaired quality of life, even between attacks. As most studies are based on subjective reports only, this study was set up to objectively quantify the interictal daily activities and heart rate of migraine patients, in relation to their subjectively reported highest realizable level of activity and of symptoms of mood in their habitual environment. Measurements were obtained during a migraine-free 2-day period of 24 patients (age range: 21-57 years) and 24 controls (age range: 18-59 years). Accelerometry was used to quantify the time spent in different postures and movements. The subjective parameters were documented by daily log. Whereas heart rate was similar for patients and controls, migraineurs were found to be significantly less physically active than controls and reported a significantly lower realizable level of activity. In addition, when active, their body motility was less than that of controls. Migraine patients also showed a higher level of sleepiness and lower level of vigour. These interictal behavioural and subjective phenomena objectively illustrate the individual and societal burden of migraine and its chronic impact on both domains.

Does aerobic training lead to a more active lifestyle and improved quality of life in patients with chronic heart failure?

BACKGROUND

Due to dyspnea and fatigue, patients with chronic heart failure (CHF) are often restricted in the performance of everyday activities, which gradually may lead to hypoactivity.

AIMS

To assess whether aerobic training leads to a more active lifestyle and improved quality of life (QoL) in patients with CHF.

METHODS

Patients with stable CHF (NYHA II/III; 59 (11) years) were randomly assigned to a training group (n=18; 3-month aerobic program above standard treatment) or control group (n=16; standard treatment without special advice for exercise). Measurements were performed on level of everyday physical activity (PA, novel accelerometry-based activity monitor) and QoL, and on several related parameters.

RESULTS

Training did not result in a more active lifestyle or improved QoL, but improved (P<0.05) peak power (17%), 6-min walk distance (10%), muscle strength (13-15%) and depression (-1.3 unit). Changes in level of everyday PA were related to changes in peak Vo(2) (r=0.58, P=0.01) and knee extension strength (r=0.48, P=0.05).

CONCLUSIONS

At group level training did not result in a more active lifestyle or improved QoL. However, correlations between training-related changes in parameters suggest that aerobic training has the potential to increase levels of everyday PA in CHF.

Daily physical activity and heart rate response in people with a unilateral transtibial amputation for vascular disease

OBJECTIVE

To study the activity level and heart rate response, objectively measured during normal daily life, of persons with a unilateral transtibial amputation for vascular disease.

DESIGN

Case comparison.

SETTING

General community, daily life in the Netherlands.

PARTICIPANTS

Nine subjects with a unilateral transtibial amputation for vascular disease (convenience sample) and 9 control subjects without known impairments (matched for sex, age, social situation, employment).

INTERVENTIONS

Not applicable.

MAIN OUTCOME MEASURES

Duration of dynamic activities, body motility (the intensity of body movement, measured with accelerometry), and heart rate (on 2 consecutive days).

RESULTS

Persons with an amputation were less active than the comparison subjects (4.3% vs 11.4% of a 48-h period, P=.007). Body motility during walking was lower in the amputee group (.111 g vs.147 g, P=.003). No differences between groups were found in normalized heart rate during walking. In the amputee group, a strong relationship was found between body motility during walking and the percentage of the day that the subject walked (r=.88, P=.002). No relationship was found between the percentage of the day that persons with an amputation were active and data from disability questionnaires.

CONCLUSION

Persons with a unilateral transtibial amputation for vascular disease were considerably less active than persons without known impairments. Heart rate response during walking of the amputee group did not differ from the response in the comparison group.

Impact of upper limb complex regional pain syndrome type 1 on everyday life measured with a novel upper limb-activity monitor

Complex regional pain syndrome type 1 (CRPS1) often leads to serious activity limitations in everyday life. To date, however, limitations in patients with CRPS1 of an upper limb have not been objectively measured.Therefore, the aim of this study was to determine the long-term impact of upper limb CRPS1 on general mobility and upper limb usage during everyday life, as measured with a novel upper limb-activity monitor (ULAM). In ten female chronic CRPS1 patients and ten healthy control subjects, 24-h activity patterns were measured with the ULAM. This ULAM consists of body-fixed acceleration sensors, connected to a recorder worn around the waist. The ULAM automatically detects upper limb activity during mobility-related activities. Several outcome measures related to general mobility and upper limb usage were compared between patients and controls. The results showed that CRPSI in the dominant upper limb had modest impact on general mobility; i.e. on the percentages spent in body positions and body motions and on mean intensity of body activity. For upper limb usage outcome measures during sitting, there was a marked difference between CRPS1 patients and controls. Especially patients with dominant side involvement clearly showed less activity of their involved limb during sitting, indicated by significant differences for the mean intensity (P=0.014), percentage (P=0.004), and proportion (P=0.032) of upper limb activity. It is concluded that these ten chronic CRPS1 patients still had limitations in upper limb usage during everyday life, 3.7 years (average) after the causative event.