An exploratory study of discrepancies between objective and subjective measurement of the physical activity level in female patients with chronic fatigue syndrome.

OBJECTIVE: To explore the ability of a self-report activity diary to measure the physical activity level (PAL) in female patients with chronic fatigue syndrome (CFS) and whether illness-related complaints, health-related quality of life domains (HRQOL) or demographic factors are associated with discrepancies between self-reported and objectively measured PAL. METHODS: Sixty-six patients with CFS, recruited from the chronic fatigue clinic of a university hospital, and twenty matched healthy controls wore an accelerometer (Actical) for six consecutive days and registered their activities in an activity diary in the same period. Participants' demographic data was collected and all subjects completed the CFS Symptom List (illness-related complaints) daily and Short-Form-36 (HRQOL domains) during the first and second appointment. RESULTS: A significant, but weak association between the activity diary and Actical was present in patients with CFS (rs = 0.376 and rs = 0.352; p < 0.001) and a moderately strong association in healthy controls (rs = 0.605; and rs = 0.644; p < 0.001) between week and weekend days, respectively. A linear mixed model identified a negative association between age and the discrepancy between the self-reported and objective measure of PA in both patients with CFS and healthy controls. CONCLUSION: The activity diary showed limited ability to register the PAL in female patients with CFS. The discrepancy between measures was not explained by illness-related complaints, HRQOL domains or demographic factors. The activity diary cannot replace objective activity monitoring measured with an accelerometer, but may provide additional information about the perceived activity.

Activity Pacing Self-Management in Chronic Fatigue Syndrome: A Randomized Controlled Trial.

OBJECTIVE: To evaluate the effectiveness of an activity pacing self-management (APSM) intervention in improving performance of daily life activities in women with chronic fatigue syndrome (CFS). METHOD: A total of 33 women with CFS (age 41.1±11.2 yr) were randomly allocated to APSM (experimental group; n=16) or relaxation (control group; n=17). Main outcome measures included the Canadian Occupational Performance Measure (COPM; primary) and Checklist Individual Strength (CIS). RESULTS: COPM scores changed significantly over time in both groups (p=.03). The change in Satisfaction scores showed a significant difference in favor only of APSM (effect size=0.74 [0.11, 1.4]). CIS scores decreased significantly in the experimental group only (p<.01). CONCLUSION: APSM was found to be feasible and effective in optimizing participation in desired daily life activities in women with CFS. Replication in a larger sample with long-term follow-up is required.

Assessment of activity limitations and participation restrictions with persons with chronic fatigue syndrome: a systematic review.

PURPOSE: To summarize measurement instruments used to evaluate activity limitations and participation restrictions in patients with chronic fatigue syndrome (CFS) and review the psychometric properties of these instruments. METHOD: General information of all included measurement instruments was extracted. The methodological quality was evaluated using the COSMIN checklist. Results of the measurement properties were rated based on the quality criteria of Terwee et al. Finally, overall quality was defined per psychometric property and measurement instrument by use of the quality criteria by Schellingerhout et al. RESULTS: A total of 68 articles were identified of which eight evaluated the psychometric properties of a measurement instrument assessing activity limitations and participation restrictions. One disease-specific and 37 generic measurement instruments were found. Limited evidence was found for the psychometric properties and clinical usability of these instruments. However, the CFS-activities and participation questionnaire (APQ) is a disease-specific instrument with moderate content and construct validity. CONCLUSION: The psychometric properties of the reviewed measurement instruments to evaluate activity limitations and participation restrictions are not sufficiently evaluated. Future research is needed to evaluate the psychometric properties of the measurement instruments, including the other properties of the CFS-APQ. If it is necessary to use a measurement instrument, the CFS-APQ is recommended. IMPLICATIONS FOR REHABILITATION: Chronic fatigue syndrome (CFS). Chronic fatigue syndrome causes activity limitations and participation restrictions in one or more areas of life. Standardized, reliable and valid measurement instruments are necessary to identify these limitations and restrictions. Currently, no measurement instrument is sufficiently evaluated with persons with CFS. If a measurement instrument is needed to identify activity limitations and participation restrictions with persons with CFS, it is recommended to use the CFS-APQ in clinical practice and scientific research.

Symptom fluctuations and daily physical activity in patients with chronic fatigue syndrome: a case-control study.

OBJECTIVES: To compare the activity pattern of patients with chronic fatigue syndrome (CFS) with healthy sedentary subjects and examine the relationship between the different parameters of performed activity (registered by an accelerometer device) and symptom severity and fluctuation (registered by questionnaires) in patients with CFS. DESIGN: Case-control study. Participants were asked to wear an accelerometer device on the nondominant hand for 6 consecutive days. Every morning, afternoon, and evening patients scored the intensity of their pain, fatigue, and concentration difficulties on a visual analog scale. SETTING: Patients were recruited from a specialized chronic fatigue clinic in the university hospital, where all subjects were invited for 2 appointments (for questionnaire and accelerometer adjustments). In between, activity data were collected in the subject's normal home environment. PARTICIPANTS: Female patients (n=67) with CFS and female age-matched healthy sedentary controls. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Accelerometry (average activity counts, peak activity counts, ratio peak/average, minutes spent per activity category) and symptom severity (intensity of pain, fatigue, and concentration difficulties). RESULTS: Patients with CFS were less active, spent more time sedentary, and less time lightly active (P<.05). The course of the activity level during the registration period (P interaction>.05), peak activity, and the staggering of activities (ratio peak/average) on 1 day were not different between groups (P>.05). Negative correlations (-.242 varying to -.307) were observed for sedentary activity and the ratio with symptom severity and variation on the same and the next day. Light, moderate, and vigorous, as well as the average activity and the peak activity, were positively correlated (.242 varying to .421) with symptom severity and variation. CONCLUSIONS: The more patients with CFS are sedentary and the better activity is dispersed, the fewer symptoms and variations they experience on the same and next day. Inversely, more symptoms and variability is experienced when patients were more active that day or the previous day. The direction of these relations cannot be determined in a cross-sectional study and requires further study.

Is the International Physical Activity Questionnaire-short form (IPAQ-SF) valid for assessing physical activity in Chronic Fatigue Syndrome?

PURPOSE: To evaluate the criterion validity and internal consistency of the International Physical Activity Questionnaire-short form (IPAQ-sf) in Chronic Fatigue Syndrome (CFS) patients. METHOD: Fifty-six CFS patients completed the IPAQ-sf after they wore a tri-axial accelerometer and filled out activity diaries during 1 week. Spearman rank correlation coefficients and Cronbach's Alpha were calculated. RESULTS: The IPAQ-sf correlated significantly with the energy expenditure and Metabolic Equivalents (METs) minutes spent moderately to vigorously active following the activity diary and accelerometer. These correlation coefficients were however low (r varying between 0.282 and 0.426) and rather irrelevant, since CFS patients hardly reach moderate or vigorous activity levels. Internal consistency between the three subitems used for the total score of the IPAQ-sf was 0.337. CONCLUSION: The observed associations between the IPAQ-sf data and the data obtained from the accelerometer (gold standard) and the diaries were too low to be in support of the use of the IPAQ-sf in patients with CFS. The IPAQ-sf does not seem an appropriate tool to assess physical activity in CFS patients. Further study is required to seek for a valid, practical and affordable tool.

Nitric oxide concentrations are normal and unrelated to activity level in chronic fatigue syndrome: a case-control study.

AIM: since patients with chronic fatigue syndrome (CFS) often present elevated levels of nitric oxide (NO) and low levels of physical activity, this study aimed at revealing possible correlations between NO concentration and physical activity. PATIENTS AND METHODS: thirty CFS patients and 29 age- and gender-matched sedentary controls wore an accelerometer for one week and underwent venous blood sampling at the beginning and the end of the week. RESULTS: CFS patients were significantly less active (p=0.001), but no significant differences in the amounts of NO (p=0.464 and 0.569) or interaction between NO levels and activity levels in either the CFS patients or controls were revealed. CONCLUSION: these results provide further evidence for reduced activity levels in CFS patients, but refute there being any interaction between the amount of blood NO and activity level in both groups. The blood NO was neither predictive of, nor dependent on the activity level in CFS.

Can pacing self-management alter physical behavior and symptom severity in chronic fatigue syndrome? A case series.

Given the lack of evidence in support of pacing self-management for patients with chronic fatigue syndrome (CFS), we examined whether physical behavior and health status of patients with CFS would improve in response to a pacing self-management program. We performed an observational study of pacing self-management in seven CFS patients using a single-case study design. Stages A1 and A2 (7-day assessment periods) of the A1-B-A2 design corresponded to the baseline and posttreatment measurements of physical behavior (real-time activity monitoring) and health status (self-reported measures), respectively. Stage B (3 weeks of treatment) consisted of three individual treatment sessions of pacing self-management. When comparing pre- versus posttreatment data, we found that the patients' ability to perform daily activities and the severity of their symptom complexes were improved (p = 0.043). Concentration difficulties, mood swings, muscle weakness, and intolerance to bright light improved as well. A statistically significant decrease in the mean time spent doing light activity (<3 metabolic equivalents) was observed, but a change in the way physical activity was spread throughout the day was not. We found that 3 weeks of pacing self-management was accompanied by a modest improvement in symptom severity and daily functioning. The outcome of the present study calls for a randomized controlled clinical trial to examine the effectiveness of pacing self-management for people with CFS.