in recent years , researchers have become increasingly interested in one of the most common and persisting complaints after stroke , that is , poststroke fatigue ( psf ) .
psf is best described as a feeling of early exhaustion with weariness , lack of energy and aversion to effort   that develops during physical or mental activity and is usually not ameliorated by rest [ 2 , 3 ] .
the percentages of patients reporting fatigue after stroke range from 38% to 77% , and these percentages do not seem to decline in the chronic stage [ 46 ] .
furthermore , psf appears to be related to higher mortality rates and poorer rehabilitation outcomes .
however , the pathogenesis of psf is still poorly understood and , until now , effective treatments are still lacking [ 4 , 8 ] . although the mechanisms leading to psf are still elusive , its origin is believed to be multifactorial .
psf may be a direct result of organic brain damage , as it has often been reported in other types of brain disease , such as traumatic brain injury .
however , only a few associations of fatigue with biological markers have been reported in the stroke population .
in other words , although stroke severity may play a role , there is little evidence linking lesion size or location to psf [ 35 , 11 ] .
the origin of psf could also be related to psychosocial factors , which has been the focus of numerous studies ( see lerdal et al . , 2009 ,   for an overview ) .
of all psychosocial factors , the most investigated are depression , anxiety , coping skills , social support , and self - efficacy .
because fatigue is generally considered as a symptom of depression , an overlap between both phenomena seems undeniable [ 1 , 4 , 9 ] .
indeed , an association between fatigue and depressive symptoms is a consistent finding in the literature not only in stroke patients [ 2 , 57 , 1114 ] , but also in patients with traumatic brain injury   and in otherwise healthy subjects [ 10 , 13 ] . yet , in those studies that specifically looked at patients who suffer from depressive symptoms and/or fatigue , a clear dissociation between the two phenomena was also present with groups of patients reporting just fatigue or just depression [ 5 , 6 , 11 , 15 ] . the same seems to be true for anxiety .
the studies that have examined coping style , self - efficacy , and social support suggest that emotion - oriented coping [ 2 , 16 ] , locus of control directed to powerful others , and lack of social support   are also associated with psf .
these studies are , however , few in number and cross - sectional in design and did not specifically focus on patients for rehabilitation purposes . as a result , the nature of the psychosocial profile of patients suffering from psf is still largely unknown , providing only scant clues for optimizing the treatment of psf [ 4 , 8 ] .
the aim of this study was to compare a psychological and social profile of stroke patients , with severe psf selected for rehabilitation , to the one of healthy control subjects and patients with other chronic diseases and to investigate the strength of the association between fatigue and several psychosocial variables .
data were gathered from patients with psf who participated in a larger multicenter study ( cograt : effectiveness of cognitive and graded activity training on psf ) . in this study , 231 patients were recruited via their treating physicians and psychologists ( n = 64 ) , through an article about the cograt study in various newspapers ( n = 151 ) , or based on their consent for renewed contact given in earlier studies ( n = 16 ) .
the study was approved by the local ethics committee and all eligible subjects signed an informed consent . for the cograt study outpatients in the chronic stage of stroke ( at least 4 months after stroke ) were identified according to the following criteria : ( 1 ) age between 18 and 70 ; ( 2 ) last stroke episode longer than 4 months ago ( either cerebral infarction , or intracerebral or subarachnoid hemorrhage ; single or recurrent stroke ) ; ( 3 ) severe fatigue ( checklist individual strength 20r - fatigue subscale    40 ) ; ( 4 ) ability to walk independently .
patients were excluded from the study if they had ( 1 ) severe visual hemineglect , behavioural inattention test  129 , ( 2 ) severe memory deficits ( rivermead behavioural memory test   screening score < 8) , ( 3 ) executive impairments ( behavioural assessment of the dysexecutive syndrome   < borderline ) , ( 4 ) moderate to severe aphasia ( token task   > 12 ) , ( 5 ) severe cardiac or pulmonary disease , or ( 6 ) co - morbid depression ( hospital anxiety and depression scale depression scale > 10 ) . if the hads depression scale score was between 8 and 10 , a clinical interview ( mini dsm - iv ) was conducted to exclude patients with clinical depression .
of the 124 excluded patients , 47 ( 54% ) were not severely fatigued and 21 had too high levels of depression .
the remaining 56 patients met one or more other exclusion criteria , such as memory deficits , mobility deficits , or aphasia .
these participants did not differ significantly with regard to age and gender ( alpha = 0.05 ) from the nonparticipants and those excluded based on too high levels of depression .
data on age , sex , marital status , educational level , and stroke type and side were obtained from the patients and their medical records .
severity of paresis was assessed with the motricity index ( mi ) of the affected lower extremity .
the mi was recorded because lower extremity paresis is strongly related to balance   and mobility after stroke , and mobility might be associated with poststroke depression .
two widely used and well - validated measures of fatigue were used in this study , the subscale fatigue of the checklist individual strength 20r ( cis - f )   and the fatigue severity scale ( fss ) . 
the cis - f consists of 8 out of 20 items of the questionnaire , asking about fatigue severity in the two weeks before the assessment , to be indicated on a 7-point likert scale ( range 856 ) .
patients with a score 40 on this subscale were defined as being severely fatigued . in the fss
, individuals rate their agreement with nine statements on a 7-point likert scale concerning fatigue severity , frequency , and impact on daily life . the mean score ( range 17 )
the threshold for moderate to high impact of fatigue using the fss is commonly set at either 4 or 5 .
to study the psychosocial characteristics of patients with psf , self - report questionnaires regarding depression , anxiety , psychological distress , coping , social support , and self - efficacy were used .
depression and anxiety were measured with the hospital anxiety and depression scale ( hads ) .
the hads is a 14 item self - report measure , with seven items forming a depression subscale and another seven constituting an anxiety subscale .
each item is rated on a four - point scale , ranging from 0 to 3 , with 3 reflecting the highest distress .
total scores for each subscale range from 0 to 21 and are categorized as normal ( 07 ) , mild ( 810 ) , moderate ( 1114 ) , or severe ( 1521 ) . the symptom checklist-90 ( scl )   measures psychological distress .
nine psychopathology scores can be derived and the total score ( gsi ) reflects a global severity index of psychological distress .
furthermore , a personality severity index ( psi ) to assess personality problems can be calculated .
this is done by transferring raw scores to scl-90r scales , and then comparing the mean scores of the scales interpersonal sensitivity , hostility , and paranoid ideation to the mean value of the remaining scales .
forty - eight items are scored on a 5-point likert scale , resulting in three subscales : problem - focused coping , emotion - focused coping , and avoidance - focused coping .
social support was assessed with the social support list ( ssl-12 )   that consists of twelve statements regarding perceived positive and negative social support from the primary social network .
positive support is described by three subscales : everyday support , support in problem situations , and esteem support .
the self - efficacy scale ( ses ) was used to assess the sense of control in relation to fatigue complaints .
the total scores ranges from 5 to 25 , with a higher score reflecting more sense of control .
descriptive statistics ( i.e. , mean and standard deviation ( sd ) ) were calculated for all psychosocial characteristics .
these values were compared to known reference values and derived z - scores from healthy controls and patient populations ( general practice , traumatic brain injury , chronic pain , multiple sclerosis , parkinson , cancer , rheumathoid arthritis , and chronic fatigue syndrome ) reported in the literature [ 28 , 29 , 32 , 33 , 3537 ] .
based on these z - scores different categories were labeled as follows : < 1.28 = very low , < .84 = low ,
< .525 = below average , between .525 and  .525 = average , > .525 = above average , > .84 high and > 1.28 very high .
the presence of personality problems was determined by calculating a psi from the raw scores of the scl .
associations between the cis - f - fss fatigue scales and gender , marital status , lesion characteristics , and psi were calculated with 2 analyses .
spearmen rank correlations were calculated with the ordinal demographical , stroke , and psychosocial characteristics .
then a stepwise multiple regression analysis was performed on the variables significantly associated with fatigue to establish their unique contribution .
all data analyses were computed with spss version 17.0 , using holm 's correction to adjust for multiple analyses .
demographic data , severity of paresis , fatigue scores , and stroke characteristics are summarized in table 1 .
scores on both fatigue scales indicated on average  severe fatigue .  on the cis - f , 92.0% of the subjects scored above 40 . on the fss
mean postonset time since last stroke was 4.3 years , which did not differ significantly between single and recurrent strokes . to investigate the psychosocial characteristics of our patients ,
the scores were compared to reference values obtained from norm groups of healthy controls and patient groups from general health practice and with various chronic afflictions ( table 2 ) .
the hads anxiety scores were comparable to other patient groups but high when compared to the general population . using
the z - score derived , abovementioned categories , 60.2% of the patients had normal , 17% mild , 18.2% moderate , and 4.5% severe scores on hads - anxiety . on the depression subscale of the hads , we found high scores compared to both the general population and general practice patients .
still , 64.8% of our subjects had normal and the remaining 35.2% only mild depressive symptoms .
the scores on the scl were generally high compared to healthy controls , but in comparison to other patient groups the scl scores were average , except for the subscale  obsessive compulsive  which was above average , reflecting more subjective cognitive complaints .
the psi is a categorical value and could therefore not be compared to reference values .
nevertheless , the incidence rate indicated that 93.2% of the patients were free from personality problems .
as for coping strategies , our patients showed slightly lower levels of problem - focused and avoidance strategies than healthy controls .
however , in comparison to other patient groups , they scored average or above average for all strategies .
furthermore , our patients received more positive social support with as many negative social interactions compared to healthy controls and other patient groups .
compared to patients with chronic fatigue syndrome ( cfs ) , they reported to be  more in control  when assessed with the ses . 

table 3 shows the correlation coefficients of demographic , clinical , and psychosocial characteristics with both fatigue scores .
no associations with either fatigue scale ( cis - f or fss ) were found for demographic data , stroke characteristics , or severity of paresis ( mi ) .
the cis - f scale showed a statistically significant but moderate association with scl - somatic and scl - depression .
multiple regression analysis was performed only for the cis - f with associated variables , since the fss correlated with just one psychosocial variable ( table 3 ) .
scl - som significantly predicted cis - f scores ,  = .54 , t(86 ) = 5.89 , p < .001 .
scl - dep did not add significantly to the model ( p = .78 ) with no concerns for multicolinearity ( vif = 1.56 , tolerance =  .64 ) .
the aim of this investigation was to obtain a psychosocial profile of patients suffering from severe psf in order to tease out options for the rehabilitation of fatigue .
the results of this study suggest , however , that these patients are not characterized by a distinct psychosocial profile . in comparison to healthy controls ,
psf - patients reported high psychosocial distress , high positive social support , and low problem - focused coping .
however , compared to other chronic patient groups , we found no marked discrepancies with regard to distress , coping styles , social support , and self - efficacy .
moreover , independent associations with fatigue were only found for scl - somatic complaints with cis - f ( r = .54 ;
p < .001 ) and scl - obsessive compulsive with fss ( r = .35 ; p < .001 ) , but not for any other psychosocial variable or stroke characteristic ( e.g. , time since stroke , single versus recurrent , nature of lesion , and lesion side )
. the subscale obsessive compulsive of the scl might mimic the direct neurological consequences of stroke , since it includes items such as  trouble with thinking ,   mental slowness ,   needing to check things  and  thinking things over . 
although no direct association between fatigue severity and severity of cognitive deficits has been found [ 4 , 5 , 14 ] , a relationship between fatigue and cognitive complaints , such as mental slowness , has been substantiated [ 13 , 39 ] . a probable cause for the experienced fatigue may be found in this light .
cognitive deficits may temporarily be compensated for by exerting increased mental effort , which then may cause fatigue .
indeed , widespread brain activity has been shown in patients with unilateral lesions of one cerebral hemisphere trying to perform a unimanual task with their affected hand .
such activities typically require a great amount of attentional resources , because subjects act at the limits of ( or even beyond ) their functional capacities .
a parallel can be drawn from studies of traumatic brain injury where affected individuals showed more dispersion and more brain regions activated when engaged in an attention task than healthy controls [ 43 , 44 ] .
thus , psf might be associated with underlying cognitive mechanisms that are independent of the extent of the brain lesion and of psychopathological problems related or unrelated to stroke .
if this notion is valid , it would be consistent with the finding that fatigue is almost as frequent in relatively mildly affected patients as in the more severely affected ones [ 4 , 5 ] , because it will become a problem whenever subjects try to overcome their individual subtle or severe limits .
as soon as subjects are able to deal with their functional limitations more effectively , taking into account their limited attentional capacity and mental energy , fatigue may gradually become less severe .  
the association between fatigue and somatic complaints could also be seen in line with this hypothesis .
somatic complaints may reflect the direct physical consequences of stroke , causing functional limitations and/or pain , requiring more task - related physical and mental effort and thereby provoking fatigue .
another part of the somatic complaints could be explained as the physical expression of fatigue .
for example , many patients report a heavy feeling in arms and legs , nausea , or headaches when becoming tired . as in previous studies , we first found an association between depression and fatigue on one of our fatigue scales [ 2 , 57 , 1114 ] .
a variant of this moderating effect has been previously reported in a study wherein the association between fatigue and depression became weaker , when controlled for by sickness and impact on ambulation .
this finding emphasizes not only the dissociation of fatigue and depression , but also the need to assess physical complaints in depth .
a rather unexpected but noteworthy finding of this study was that both fatigue measurements used , the fss and cis - f , were associated with completely different variables as shown in table 3 .
the use of more than one fatigue scale in clinical practice and research might therefore be warranted .  
furthermore , our inclusion criteria restricted the variability of fatigue and mobility , thereby possibly lowering associations .
the exclusion of patients with severe cognitive deficits , depression and motor problems might be considered both a strength and a limitation of this study .
the major limitation is that it precludes generalization to other stroke patients . on the other hand , this choice enabled us to single out the relationship between fatigue and psychosocial factors , without the influence of these confounding factors .
by comparing our study group to other reference groups , psf patients displayed a  normal chronic patient  psychosocial profile .
we therefore propose that ( a part of ) the fatigue might be a consequence of the inadequate adaptation to diminished and or less efficient attentional resources after stroke .
graded physical activity programs might be an important contribution to the treatment of psf , since exercise has been found to be helpful in improving physical and functional outcomes and to reduce fatigue in various other medical conditions [ 45 , 46 ] .
such programs might help stroke patients to gradually increase physical activity without experiencing distressing bodily symptoms .
second , cognitive compensation strategies circumventing the limited energetic resources available to patients suffering from psf might also be beneficial .
these compensation strategies could entail an enhanced planning and variation of activities to foster a more regular pattern of activity and rest . here
, patient education and goal setting could be added to improve patient motivation and adherence .
third , since symptoms of depression and anxiety are common in psf patients , it is important to address these when present , since they may compromise self - management .
it takes into account cognitive deficits and grievance of loss of abilities and could also aid in implementing the behavioral changes needed to apply compensation strategies .
lastly , our results point to the use of more than one scale to assess psf , highlighting that fatigue is not only a common but also a complex and multifaceted syndrome .
 
 objective . to obtain a psychosocial profile of patients with poststroke fatigue ( psf ) , which could aid in optimizing treatment strategies 
 . methods . 
 eighty - eight outpatients with severe psf measured with the checklist individual strength - fatigue subscale ( cis - f ) and the fatigue severity scale ( fss ) were selected . 
 depression and anxiety , psychological distress , coping , social support , and self - efficacy of this group were compared to reference groups of healthy controls and patients with other chronic diseases . 
 associations between psychosocial characteristics and fatigue were calculated . results . compared to healthy controls , patients with psf reported more psychological distress , less problem - focused coping , and more positive social support . 
 minor or no differences were found in comparison with other chronic patients . 
 the cis - f correlated with somatic complaints and the fss with cognitive complaints . 
 conclusion . 
 patients with psf show a psychosocial profile comparable to patients with other chronic disease . implications for diagnosis and treatment are discussed . 
1. Introduction
2. Methods
3. Results
4. Discussion
5. Conclusions and Implications for Treatment