Subjective Fatigue Complaints Research Articles

Further evidence for the reliability and validity of the Fatigue and Daytime Sleepiness Scale

BackgroundMyotonic dystrophy type 1 (DM1) is an inherited neuromuscular disease causing, among other symptoms, fatigue and excessive daytime sleepiness, which are frequently undifferentiated by patients and/or clinicians. The Fatigue and Daytime Sleepiness Scale (FDSS) has been devised to measure these two overlapping symptoms as a single clinical entity. ObjectiveTo further examine the reliability and the construct validity of the FDSS in patients with DM1. MethodsThe scale was administered to 48 DM1 patients on two occasions at a 2week-interval. Intra-rater reliability and internal consistency were established by calculating the intraclass correlation coefficient (ICC) and Cronbach's alpha, respectively. Construct validity was assessed by using the known-group method. More precisely, the mean FDSS score of patients with and without subjective complaints of fatigue and/or sleepiness was compared. ResultsThe FDSS showed good intra-rater reliability (ICC=0.83) and acceptable internal consistency (Cronbach's alpha =0.6). Also, the FDSS was able to distinguish between patients who had fatigue and sleepiness complaints from those who did not (mean FDSS score of 10.6 vs 8.0, p=0.01), suggesting good construct validity. ConclusionOverall, the present study supports the continued use of the FDSS as a reliable and valid instrument to measure fatigue and daytime sleepiness in patients with DM1 for either clinical or research purposes.

An objective measure combining physical and cognitive fatigability: Correlation with subjective fatigue in Parkinson's disease

BackgroundObjective measures of physical and cognitive fatigability do not correlate with subjective Parkinson's disease (PD)-related fatigue. The relationship of subjective PD-related fatigue to tasks combining cognitive and motor effort has never been explored. MethodsForty-four right-handed, non-demented PD patients, 22 with (PD-F) and 22 without (PD-NF) fatigue, were tested using a sensor-engineered glove on their more affected hand. Patients performed sequential opposition finger movements following a metronome at 2 Hz for 5 min (cued task), and for another minute following a 2-min rest. The same task was repeated without sustained auditory cueing. Movement time (inter-tapping interval, ITI) and rate, touch duration, percentage of correct sequences and clinical measures (motor and fatigue severity, depression, sleep impairment and apathy) were analysed. ResultsIn the cued task, motor performance worsened over time (significantly increased ITI and decreased movement rate on the third to fifth minute) in PD-F patients only. In the uncued task, motor performance deteriorated similarly in the two groups. PD-F and PD-NF patients differed in ITI and movement rate deterioration over time only in the cued task, independently from motor severity, depression and sleep impairment. The severity of subjective fatigue complaints significantly correlated with motor performance deterioration in the cued task. ConclusionsPD-related fatigue is associated with performance on an externally cued, attention-controlled motor task, but not with an uncued version of the same task. The finding supports a link between PD-related fatigue and attention-demanding motor tasks, proposing a model of inducible fatigue applicable to future clinical and neuroimaging research.

The Effects of Performance Fatigability on Postural Control and Rehabilitation in the Older Patient.

Fatigue is common in older adults and has a significant effect on quality of life. Despite the high prevalence of fatigue in older individuals, several aspects are poorly understood. It is important to differentiate subjective fatigue complaints from fatigability of motor performance because the two are independent constructs with potentially distinct consequences on mobility. Performance fatigability is the magnitude of change in a performance criterion over a given time of task performance. Performance fatigability is a compulsory element of any strength training program, yet strength training is an important component of rehabilitation programs for older adults. The consequences of fatigability for older adults suggest that acute exercise of various types may result in acute impairments in postural control. The effects of performance fatigability on postural control in older adults are evaluated here to aid the rehabilitation clinician in making recommendations for evaluation of fall risks and exercise prescription.

Parkinson's disease-related fatigue: A case definition and recommendations for clinical research.

Fatigue is one of the most common and disabling symptoms in Parkinson's disease (PD). Since fatigue was first described as a common feature of PD 20 years ago, little progress has been made in understanding its causes or treatment. Importantly, PD patients attending the 2013 World Parkinson Congress voted fatigue as the leading symptom in need of further research. In response, the Parkinson Disease Foundation and ProjectSpark assembled an international team of experts to create recommendations for clinical research to advance this field. The working group identified several areas in which shared standards would improve research quality and foster progress including terminology, diagnostic criteria, and measurement. Terminology needs to (1) clearly distinguish fatigue from related phenomena (eg, sleepiness, apathy, depression); (2) differentiate subjective fatigue complaints from objective performance fatigability; and (3) specify domains affected by fatigue and causal factors. We propose diagnostic criteria for PD-related fatigue to guide participant selection for clinical trials and add rigor to mechanistic studies. Recommendations are made for measurement of subjective fatigue complaints, performance fatigability, and neurophysiologic changes. We also suggest areas in which future research is needed to address methodological issues and validate or optimize current practices. Many limitations in current PD-related fatigue research may be addressed by improving methodological standards, many of which are already being successfully applied in clinical fatigue research in other medical conditions (eg, cancer, multiple sclerosis). © 2016 International Parkinson and Movement Disorder Society.

Subjective Fatigue and Stress Hormone Levels in Urine according to Duration of Shiftwork

To determine the associations between urinary catecholamines and cortisol and subjective complaints of fatigue in shiftworkers, we conducted a field survey of 113 male shiftworkers at a manufacturing company in South Korea from late October to late November in 1999. The shiftwork system in the company was the backward rapidly rotating 4-crew 3-shift, with the morning shift starting at 7:30 AM. Using a self-report questionnaire, we assayed demographic characteristics, past medical history and working hours, as well as subjective complaints of fatigue in 3 categories of questionnaire. We found that, among workers with less than 5 yr of shiftwork experience, the concentrations of norepinephrine, epinephrine (Epi), and dopamine during the afternoon shift were positively correlated with Set II (difficulties in concentration) and Set III (projection of disintegration) of subjective fatigue symptoms. In addition, Epi concentrations were positively correlated with Set I (drowsiness and dullness), II, and III of subjective fatigue symptoms during the night shift. However, among workers with 5 or more years of shiftwork experience, there was no significant positive correlation between urinary catecholamine and subjective fatigue symptoms. In the long term shiftwork experience group, only the complaints scores of Set II fatigue symptoms (difficulties in concentration) during the morning shift were significantly higher than those of the short-term shiftwork experience group within the same shift.

Effects of shift schedules on fatigue and physiological functions among firefighters during night duty

To examine the effects of shift schedules on fatigue and physiological functions among firefighters a 17-day field study at a fire station was carried out. Eleven firefighters, who were engaged in firefighting emergency services, participated in this study. At the fire station, night duty (22:00–07:00) was divided into 5 periods (P1: 22:00–00:00; P2: 23:45–01:45; P3: 01:30–03:30; P4: 03:15–05:15; P5:0 5:00–07:00). The participants were assigned to one of these 5 periods and awakened to answer calls from the city's central information centre. They took naps in individual rooms during night duty, except when on night shift or when called out on an emergency. Subjective complaints of fatigue, critical flicker fusion frequencies, 3-choice reaction times, and oral temperature were measured before and after work and following breaks during their 24 working hours. Heart rate variability was also recorded to evaluate autonomic nerve activity. The results show that during P3 and P4, participants who had to wake up at midnight took shorter naps. The rates of subjective complaints regarding P3 and P4 tended to be higher than those for P1, P2, and P5. The ratios of the low frequency component of heart rate variability to the high frequency component during P4 were significantly lower than those during P5. It is assumed that such an irregular sleeping pattern causes many complaints of subjective fatigue, and adversely affects physiological functions. A night-duty shift schedule ensuring undisturbed naps should be considered.

An Attempt for Diet and Developing Health-Questionnaires Based on the Concept of “Sho”

This study was designed to develop questionnaires with a view to providing advice about workers' healthy life.First, 169 workers (62 males and 107 females) in Toyama City were asked about three questionnaires.One cocerned diet problems, the next Japanese Oriental Kampo medicine, and last two subjective complaints of fatigue.Based on the total results, the workers' constitutions were classified into four categories about the concept of “sho” .The “lungs-deficiency” was the highest rate (7.4%) about “no tea break and having three meals” and the “kidneys-dificiency ” was the highest rate (16.3%) about “tea break and no having three meals” .The results of the hightest rate of questionnaire on subjective complaints of fatigue was the “liver-dificiency” and lowest was the “lungs-deficiency” .So the “lungs-deficiency” was most desirable judgement about meals and fatigue complaiants and the “liver-deficiency” was poor about both.

Long working hours and subjective fatigue symptoms.

Presuming that overtime work may associate with chronic fatigue and then decrease cardiovascular function, this report was prepared to find out the definite positive relationship between long working hours and subjective fatigue complaints. We analysed the data of a field survey of 238 men who were working at the department of research & development of three electronics manufacturing companies in S. Korea. The field survey consisted of self-report questionnaires on the working hours, health conditions, and fatigue. For data analysis, the subjects were divided into 3 groups on the criteria of 60 and 70 working hours per week: less longer (LLWH), longer (LWH), and more longer (MLWH) working hour groups. We compared the age-adjusted mean % scores of fatigue complaints among LLWH, LWH, and MLWH. The rate of complaints of subjective fatigue before going to work for LWH and MLWH tended to be significantly higher than those for LLWH. Hence, we conclude that the questionnaire on the subjective fatigue complaints is a good screening tool for early detection of cumulative fatigue due to chronic job stress such as long working hours.

Effect of working hours on biological functions related to cardiovascular system among salesmen in a machinery manufacturing company.

A field survey of 71 salesmen (22-60 years) in a machinery manufacturing company was conducted to investigate the effect of working hours on biological functions related to the cardiovascular system. The subjects were divided into four groups by age, and those in each age group were further divided into shorter (SWH) and longer (LWH) working hour subgroups by weekly working hours. Rates of complaints of subjective fatigue for LWH were significantly higher than those for SWH on the whole. Although the mean amplitude of respiratory sinus arrhythmia at rest decreased with age, no significant difference between SWH and LWH was found in this function. Systolic blood pressure for LWH was significantly higher than that for SWH in the 50-60 year group. The serum total cholesterol level for LWH was significantly lower than that for SWH in the 40-49 year group. Comparison of biological functions related to cardiovascular system was also made between fatigue complaint and no-complaint subgroups. Significant differences were found between the two subgroups: systolic blood pressure was higher and the total cholesterol level was lower in the fatigue complaint subgroups. Summarizing our results, it appeared that long working hours might increase systolic blood pressure and lower the total cholesterol level due to fatigue.

A study of complaints of fatigue by workers employed in Vietnamese factories with newly imported technology.

The aim was to study the actual situation of subjective fatigue among the Vietnamese workers in factories with newly imported technology. A cross-sectional study concerning working conditions and the fatigue complaints of 389 workers who are employed in 10 Vietnamese factories with newly imported technology, was conducted from August to September 1994. About 60% of the workers were satisfied with their current working conditions. Regarding occupational risks at the workplace, heat, dust and noise were identified as the three most dangerous risks. About 46% of the workers complained about the incompatibility of the machines and equipment they were using, which are too large for Vietnamese workers. One third of all workers felt that the work pace is too rapid. Seventeen percent of the workers considered their working conditions monotonous. Finally, among 150 female workers under 40 years old, 45 workers (30.0%) complained of irregularity of menstruation. Generally these problems were more common among workers in textile factories. The prevalence rate of subjective fatigue complaints was significantly increased after work in all 30 items. The fatigue level were substantially high among workers in textile factories. Female workers in this sector had a high prevalence rate of irregularity of menstruation. There were many problems observed in the Vietnamese factories with newly imported technology. Special consideration is required to improve the working conditions of female workers in the textile industry. Both the Vietnamese government and donor countries have to give special attention to the transfer of worker-friendly technology to Vietnam, in order to achieve sound economic development.

Central nervous system effects and visual fatigue in VDT workers

To assess central nervous system effects and visual fatigue induced by work with visual display terminals (VDT), symptom frequency was assessed and visual evoked potential (VEP), critical flicker fusion (CFF) and near-point distance were measured in 24 female keypunchers before and after 2.5 h of VDT work and in 6 non-VDT-exposed subjects at the same intervals. Each keypuncher had been engaged in data entry for 1-7 (mean, 4) years. After VDT work, the number of complaints of subjective fatigue as well as an objective measure of near-point distance were significantly increased as compared with those before work; also, the N75, P100 and N145 latencies of VEP were significantly prolonged. The change of P100 latency during VDT work was inversely correlated with the number of years worked in data entry. No significant change was seen in any of these tests in the non-VDT-exposed subjects. The changes in N75 latency and subjective fatigue related to drowsiness and dullness in the keypunchers were significantly larger than those in the non-VDT-exposed subjects. The CFF was significantly lower in keypunchers than in non-VDT-exposed subjects in both the first and the second tests. These data suggest that VDT work is associated with impairment of the visual nervous system function, that VEP latencies appear to be a sensitive indicator of visual fatigue, at least transiently, and that CFF appears to be a good parameter for estimations of chronic visual fatigue.

Comparative study of subjective fatigue between automatic transmission bus drivers and manual transmission bus drivers.

The difference in the physiological condition of drivers of manual transmission buses (MTB) and automatic transmission buses (ATB) was examined from the viewpoint of occupational health. This study was based on a self-administered questionnaire which involved items concerning subjective fatigue complaints. No differences in the mental fatigue and stress between MTB drivers and ATB drivers were observed. Although ATB drivers tended to feel less physical fatigue than MTB drivers, the difference was not statistically significant. From these results, it was suggested that there was little difference in the subjective fatigue between ATB drivers and MTB drivers.

An experimental study of work load on VDT performance. Part 1. Effects of polarity of screen and color of display

Study were made on the effects of polarity of screen and color of display on work load of VDT tasks. The subjects of the present experiment were eight healthy male college students (age: 21-23 yr) having a naked binocular vision of not less than 0.7 and no astigmatism nor hyperopia. The test consisted of an experimental word processing task in which the subjects visually searched e's in given sequences of alphabetical letters displayed on the CRT and converted them to 5's through keyboard operation. As for experimental conditions, four levels of screen image, that is, positive and negative screens and green and white colored displays were adopted and 2 hr were given for each operation time. Critical flicker fusion (CFF), near point distance, accommodation time, subjective fatigue symptoms, heart rate, electromyogram in upper limbs and performance score were measured. The following results were obtained. Decrease in C.F.F. and extension of near point distance were observed in all experimental conditions during the operating time. Increase in complaints of subjective fatigue related to visual function was observed in all experimental conditions after two hour VDT task. Greater extension of near point distance and larger complaints of subjective fatigue were observed in subjects using the green colored display than in those using the white colored display. This suggests that the visual load using the green colored display is larger than that using the white colored display. A larger decreased in C.F.F. and greater complaints of subjective fatigue were demonstrated in subjects using negative screen than those using positive screen. This suggests that the visual load using the negative screen is larger than that using the positive screen.