quality of life in focal, segmental, and generalized dystonia

Quality of Life in Focal, Segmental, and Generalized Dystonia

Donna Page, MSc,1 Anthony Butler, PhD,2 and Marjan Jahanshahi, PhD1*

1Cognitive–Motor Neuroscience Group, Sobell Department of Motor Neuroscience and Movement Disorders, Institute ofNeurology, University College London, The National Hospital for Neurology & Neurosurgery, London, United Kingdom;

2Dystonia Epidemiologist, Hunters Moor Regional Rehabilitation Centre, Newecastle, United Kingdom

Abstract: The objective of this study was to assess quality oflife (QoL) in a community-based sample of people with variousforms of dystonia and to identify the factors that predict QoL indystonia. QoL was assessed using two generic questionnaires:the Medical Outcomes Study Short-Form 36 (SF36) and theEuroQol questionnaire. A host of demographic, clinical, andpsychosocial variables were measured to identify the best pre-dictors of QoL in dystonia. A comparison of EuroQol and SF36scores with the norms for the general UK population of similarage showed that people with dystonia had scores indicative ofworse QoL on all domains, particularly those related to phys-ical and social functioning. The impairment of QoL was seen inall age groups and was similar for men and women. Comparedto the focal dystonia group, participants with generalized dys-tonia scored significantly worse on all QoL measures. Partici-pants who were unemployed also scored significantly worse.There was also a trend for younger and separated/divorced

participants to score worse on QoL measures. A stepwiseregression analysis revealed that functional disability, bodyconcept, and depression were important predictors of QoL indystonia. Dystonia influences various aspects of QoL, particu-larly those related to physical and social functioning. Theimpairment of QoL was greater for participants with general-ized dystonia, those who were unemployed, younger, and sep-arated/divorced. Functional disability, body concept, and de-pression were the best predictors of QoL in dystonia. Efforts toimprove health care for people with dystonia should not onlyfocus on management of the movement disorder but also con-sider modifying functional disability and negative body con-cept and depression that contribute to poor QoL in this disorder.© 2007 Movement Disorder Society

Key words: dystonia; quality of life; depression;psychosocial

Dystonia is a movement disorder characterized bysustained muscle contractions that give rise to unusualpostures or involuntary movements.1,2 Dystonia is a dis-abling and disfiguring disorder that can affect manyaspects of patients’ daily lives. The severe muscle con-tractions that characterize the disease can interfere withbasic daily functions such as walking, sitting, eating, andtalking. Due to the awkward postures, dystonia oftengives sufferers a disfigured appearance, which is associ-ated with embarrassment and can lead to social avoid-ance and isolation.3,4 Evaluation of quality of life (QoL)

is increasingly recognized as important in the assessmentand management of patients with dystonia.

Little is known about the impact of different types ofdystonia on QoL, since all of the existing studies havefocused on focal dystonia, namely cervical dystonia orblepharospasm.5–12 Thus, while some information onQoL in cervical dystonia and blepharospasm is available,there is scant information about how more extensiveforms of QoL, affecting more than one body part, that issegmental, hemi-, or generalized dystonia, affect QoL.The aim of our study was (1) to assess and compare QoLin various forms of focal, segmental, hemi-, and gener-alized dystonia in a large community-based sample and(2) to identify the predictors of QoL in these patients.

PATIENTS AND METHODS

Sample

The participants in this study were recruited from asample identified in an epidemiological study of dystonia

*Correspondence to: Dr. Marjan Jahanshahi, Sobell Department ofMotor Neuroscience & Movement Disorders, Institute of NeurologyQueen Square, London WC1N 3BG. E-mail: [email protected]

Received 29 March 2006; Revised 9 August 2006; Accepted 10August 2006

Published online 10 January 2007 in Wiley InterScience (www.interscience.wiley.com). DOI: 10.1002/mds.21234

Movement DisordersVol. 22, No. 3, 2007, pp. 341–347© 2007 Movement Disorder Society

341

in the North East of England.13 The sample of 372 peoplewith primary dystonia were approached about comple-tion of the questionnaires. Completed QoL question-naires were received from 276 people, resulting in aresponse rate of 74%.

Materials

A host of demographic, clinical, and psychosocialvariables were measured using standardized question-naires and a semistructured interview with the partici-pants. Two measures of QoL were included: the Euro-Qol, which is brief but provides good normative data,and the SF36, which provides a more comprehensiveassessment of different aspects of QoL, including socialand emotional.

Demographic Profile Questionnaire

This questionnaire was specifically developed for thestudy and covered a range of general demographic anddisease-specific questions relating to family situation,employment status, socioeconomic group, etiology ofdystonia, and medication. It was completed by one of us(A.B.) in a semistructured interview with participants.

EuroQol

The validity and reliability of the EuroQol14 have beenshown in a range of patient groups.15,16 This QoL ques-tionnaire defines health in terms of five dimensions:mobility, self-care, usual activities, pain or discomfort,and anxiety or depression, each of which are rated on athree-point scale (“no problem,” “moderate,” and “se-vere”). For each subscale, we calculated the percentageof patients who reported a moderate or severe problem.A summary index is also obtained in the form of a visualanalogue scale (VAS); ranging from 0 (worse healthpossible) to 100 (best health possible).

SF36

This is a 36-item generic measure of quality of life17

that assesses physical and mental well-being in socialand individual contexts. It has been extensively validatedand tested.18,19 Eight subscores are derived, referring toeight health concepts: physical functioning, role func-tioning (physical), bodily pain, general health, vitality,social functioning, role functioning (emotional), andmental health. Two summary scores were calculated:mental health and physical health. The subscores andsummary scores are on a scale from 0 (worst health) to100 (best health).

Beck Depression Inventory

This questionnaire measures the experience of depres-sion.20 The 21 items of the Beck Depression Inventory

(BDI) cover cognitive/affective and somatic symptomsof depression. Participants are required to indicate howthey have generally felt in the past week by selecting oneof the four statements that represent increasing severityof depression for each item. Overall scores range be-tween 0 and 63, with scores between 0 and 9 indicatingno depression, scores between 10 and 17 indicating mildto moderate depression, scores between 18 and 24 indi-cating moderate to severe depression, and scores above24 indicating severe depression.

Functional Disability Questionnaire

A 27-item scale developed by Jahanshahi and Mars-den4 measures the impact of dystonia on activities ofdaily living. Each item is rated on a five-point scale (0 �not applicable; 1 � not at all affected to 4 � severelyaffected). The internal consistency, test–retest reliability,and the construct and concurrent validity of the scalewere shown to be high.4 The total scores were used inthis study.

Body Concept Scale

The Body Concept Scale (BCS) developed by Jahan-shahi and Marsden4 consists of 22 semantic differentialscales. “My Body” is the concept to be rated at the top ofa series of seven-interval scales. An 11-point rating scale(0 � not at all disfigured; 10 � extremely disfigured) isalso included in the BCS, on which participants are askedto indicate the degree of self-perceived disfigurement.The internal consistency, construct, concurrent validity,and test–retest reliability of the scale have been shown tobe high.4 The total scores were used in this study.

Rosenberg’s Self-Esteem Scale

The 10-items of this scale assess an individual’s feel-ings of self-worth.21 The response categories constitute afive-point agree–disagree format. Scores range from 0 to20. Reliability (internal consistency, test–retest) and va-lidity (convergent and discriminant) information existsfor the Rosenberg’s Self-Esteem Scale.22

RESULTS

Due to the number of different comparisons, statisticalsignificance was only accepted at P � 0.005; differenceswith P � 0.05 were considered a trend. Published nor-mative values of the EuroQol and the SF36 in the UKpopulation were used.15,18

Demographic and Clinical Features of the Sample

A total of 66.4% of the sample was female. The meanage was 55 years (range, 16–91 years). Mean duration ofillness was 14 years (SD, 11.3 years), and mean age of

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Movement Disorders, Vol. 22, No. 3, 2007

onset was 41.2 years (SD, 16.8 years; range, 1–84 years).The majority of participants had focal dystonia (68.4%),11.4% had segmental dystonia, 7.6% had hemidystonia,3.6% had multifocal dystonia, and 9.0% had generalizeddystonia. Of the 276 participants, 60.8% were married orcohabiting and 17.8% were single. A further 8.7% wereseparated or divorced, and 12.7% were widowed. A totalof 37.3% of the sample was working. A further 22.8%were unemployed. The remainder (39.9%) were retired.The mean income of the sample was €10869.1 (SD,€9273.39). Past or current psychiatric illness was re-ported by 14.9% of the participants.

EuroQol

A moderate or severe problem in at least one dimen-sion was reported by 185 (67%) of the 276 people withdystonia (moderate � 64.9%, severe �25.7%). The most

frequently reported problems were in the domain of pain,followed by performing usual activities, and anxiety anddepression (Fig. 1). Compared with the general popula-tion, people with dystonia reported problems more fre-quently in all domains at all ages, apart from the agegroup of over 80s (Table 1; Fig. 1; only 10 participantswith dystonia were in this age group, and as such, thisresult should be interpreted with caution). Comparedwith the norms available from the general population,15

the most striking differences were in the domains of pain,performing usual activities, anxiety, and depression, with36.5% more of the people with dystonia reportingproblems.

The mean health status recorded by participants withdystonia on the VAS was 60.7 (SD, 20.3). The meanscore differed from that of the general population for allage groups. Scores on the VAS were significantly lowerin people with dystonia compared to the general UKpopulation (P � 0.001). Mean VAS values did not differsignificantly between the age groups for the dystoniapopulation (P � 0.05), but decreased significantly for thegeneral population group above 50 years of age (P �0.05).

Sex, marital status, age, and age of disease onset hadno significant effect on the VAS scores (P � 0.05). Ananalysis of variance (ANOVA) revealed that there was asignificant effect for extent of dystonia (F(4,271) � 7.83;P � 0.001), with participants with focal dystonia andsegmental dystonia scoring significantly higher on the

FIG. 1. Differences between dystonia participants and general popu-lation on EuroQol scores.

TABLE 1. The percentage of respondents reporting problems on the various dimensions of the EQ-5D, by age in comparison tothe general UK population normative data

Age group (yr)

20-29 30-39 40-49 50-59 60-69 70-79 �80

General UK population (N) 620 683 543 461 475 406 140Dystonia Patients (N) 14 29 51 68 66 38 10

EQ-5D dimensionMobility

UK population 5 7.8 10 21 29 39 56Dystonia participants 78.6 41.4 54.9 47.1 53.0 60.5 40.0

Self-careUK population 1 1.6 4.2 5.2 5.7 7.4 16Dystonia participants 50.1 20.7 35.3 20.6 24.2 23.7 40.0

Usual activitiesUK population 7.1 8.6 10 21 24 26 44Dystonia participants 85.7 62.1 80.4 64.0 74.3 73.7 50.2

PainUK population 15 19 25 43 46 56 60Dystonia participants 64.3 65.5 88.2 86.8 77.3 79.0 50 .1

Anxiety/depressionUK population 13 17 18 27 28 25 24Dystonia participants 58.6 58.6 60.8 69.3 66.7 71.0 30.0

Data from Kind et al., 1998.EQ-5D, the EuroQol five-dimensions questionnaire; UK, United Kingdom.

QUALITY OF LIFE IN DYSTONIA 343


VAS compared to participants with generalized dystonia(P � 0.001). There was a significant effect for employ-ment status (F(2,276) �12.50; P � 0.001), with em-ployed participants scoring significantly higher on theVAS compared to participants who were unemployed(P � 0.001). Extent of dystonia had a significant effecton the EuroQol summary index score (F(4,271) � 9.25;P � 0.001). Post hoc analysis showed that participantswith focal and segmental dystonia scored significantlyhigher than participants with generalized dystonia on thesummary index scores (P � 0.001). Additionally, em-ployment status had a significant effect on the EuroQolsummary index scores (F(2,276) �16.65; P � 0.001).Participants who were working scored significantlyhigher on the summary index compared to unemployedparticipants (P � 0.001). Finally, there was a trend forparticipants in the younger age groups to have signifi-cantly worse summary index scores (F(5,271) � 2.52;P � 0.03) and a trend for participants who were divorcedor separated to have significantly worse scores(F(3,275) � 2.55; P � 0.05). Sex and age of diseaseonset had no effect on the summary index scores (P �0.05).

SF36

Lower scores on the SF36 reflect poorer health status.A comparison of SF36 scores with the data from thegeneral UK population of a similar age18 showed that thedystonia participants had scores indicative of worse QoLon all eight domains of the SF36 (Table 2). The lowestscores reported by participants were in the domains ofrole limitations (physical), vitality, and general health aswell as in social and physical functioning compared withthe norms available from the general population.18

An ANOVA revealed that there was a significanteffect of extent of dystonia on the SF36 physical sum-mary (F(4,276) � 8.79; P � 0.001) and mental summaryscore (F(4,276) � 4.568; P � 0.001). Post hoc analysisrevealed that participants with focal dystonia scored sig-nificantly higher on the physical summary and mentalsummary scores than participants with generalized dys-tonia (P � 0.001). Additionally, employment status hada significant effect (F(2,273) �10.8; P � 0.001) on thephysical summary score and the mental summary score(F(2,273) � 9.82; P � 0.001). Participants who wereworking scored significantly higher on the physical and

TABLE 2. Mean SF36 scores (lower scores indicate poorer quality of life) by age in comparison to the general UK populationnormative data

f

16-24 25-34 35-44 45-54 55-64 �65

General UK population (N) 240 357 298 267 230 103Dystonia patients (N) 6 29 41 57 66 77

SF36Physical functioning

UK population 94 95 89 84 74 60Dystonia participants 47.1 73.4 55.4 64.6 57.5 52.1

Social functioningUK population 91 89 87 87 84 80Dystonia participants 54.7 62.4 47.8 59.3 61.2 65.4

Role limitations - physicalUK population 92 90 81 83 72 59Dystonia participants 25.3 40.1 20.0 35.3 36.5 37.3

Role limitations – emotionalUK population 84 84 81 82 80 73Dystonia participants 62.6 55.8 46.1 50.0 62.0 53.2

Mental healthUK population 74 73 70 72 74 73Dystonia participants 65.2 56.5 55.1 59.8 60.8 63.5

PainUK population 68 63 58 59 59 57Dystonia participants 45.8 42.1 36.6 44.0 42.9 41.0

VitalityUK population 87 84 78 77 73 67Dystonia participants 57.0 61.0 45.3 56.1 58.2 64.1

General healthUK population 76 77 72 70 65 58Dystonia participants 51.0 45.3 45.2 51.5 50.6 48.1

Data from Brazier et al., 1992.SF36, Short Form 36; UK, United Kingdom.

344 D. PAGE ET AL.


mental summary scores compared to unemployed partic-ipants (P � 0.001). Finally, there was a trend for partic-ipants who were separated or divorced to have signifi-cantly worse mental summary scores (F(3,275) �2.74;P � 0.04). Sex, age, or age of disease onset, had nosignificant effect on the physical or mental summaryscores (P � 0.05).

Predictors of QoL in Dystonia

To determine which factors contributed most to theEuroQol and SF36 scores, we performed a series ofstepwise linear regressions. The participants’ scores onthe Functional Disability Questionnaire (FDQ), BCS dis-figurement ratings, BDI, and self-esteem scale, and allfactors that were shown to have an impact on QoL scoresin the above analyses were entered into the regressionanalysis in a stepwise manner (see Table 3). For theEuroQol, the most important predictive factor was func-tional disability, followed by body concept, which to-gether accounted for 42% of the variance of EuroQolScores. Extent of Dystonia accounted for a further 1% ofthe variance of the EuroQol scores. For the SF36 phys-ical summary score, the most important predictive fac-tors were body concept (44%), functional disability(5%), disfigurement (1%), and employment status (1%).For the SF36 mental summary score, the most important

predictive factors were body concept and BDI depressionscores, which together accounted for 34% of the vari-ance. For each regression analysis, at each step, R wassignificantly different from zero and the increment of R2

was significant (P � 0.001). Because of the primacy offunctional disability and body concept as predictors ofQoL in dystonia, two further stepwise multiple regres-sion analyses were performed to identify the variablesthat made the most significant contributions to the vari-ance of functional disability and body concept,respectively.

BDI, disfigurement, and extent of dystonia accountedfor 53% of the variance in body concept and 41% of thevariance in functional disability scores. Employment sta-tus was a contributing factor and accounted for 4% of thevariance of FDQ scores and 1% of the variance of BCSscores. Finally, self-esteem accounted for 1% of thevariance in body concept.

DISCUSSION

This study with a large community-based sample ofpeople with a range of different forms and extents ofdystonia found that the main impairment of QoL indystonia lies in the domains of social and physical func-tioning, pain, anxiety, and depression. QoL was affectedby the extent of dystonia, with participants with gener-alized dystonia having poorer QoL than those with focaldystonia. Employment status also had an impact, withpoorer QoL in the unemployed participants. There was atrend for younger participants and separated/divorcedpatients to have poorer QoL. In contrast, sex and age ofdisease onset did not affect QoL. Functional disability,body concept and a sense of disfigurement, depression,and extent of dystonia were the predictors of QoL indystonia. The emergence of depression as one of themajor predictors of QoL in our sample with focal, seg-mental, hemi-, and generalized dystonia confirm thefindings of Ben-Shlomo and colleagues (2002) with cer-vical dystonia, who found depression and anxiety to bethe most important predictors of QoL.

Previous work on cervical dystonia has established thecentral contribution of body concept and disfigurementin determining the psychosocial adjustment of peoplewith this disorder.3,4,23 In cervical dystonia, depression ischaracterized by a negative view of the self relating tothe disturbed body image and low self-esteem associatedwith the disfigurement resulting from the head devia-tion.3 Self-rated disfigurement was the most importantpredictor of depression for the patients with cervicaldystonia.4 The present results identifying poor body con-cept, sense of disfigurement, functional disability, anddepression as the predictors of QoL in dystonia, confirm

TABLE 3. Results of the stepwise multiple regressionanalyses performed to identify the predictors of QoL

Step Variable

Standardizedregressioncoefficient R2

R2(change)

Prediction of EuroQol1. Functional disability �0.61 0.37 0.372. Body concept �0.26 0.42 0.043. Extent of dystonia �0.11 0.43 0.01

Prediction of physical summary score(SF36)1. Body concept �0.67 0.44 0.442. Functional disability �0.29 0.50 0.053. Disfigurement �0.17 0.51 0.014. Employment status �0.11 0.53 0.01

Prediction of mental summary score(SF35)1. Body concept �0.55 0.30 0.302. BDI �0.25 0.34 0.04

Prediction of functional disability1. Disfigurement 0.57 0.32 0.322. Extent of dystonia 0.26 0.39 0.063. Employment status 0.21 0.43 0.044. BDI 0.19 0.46 0.03

Prediction of body concept1. BDI 0.66 0.43 0.432. Disfigurement 0.33 0.52 0.083. Self-esteem �0.25 0.55 0.024. Extent of dystonia 0.15 0.57 0.025. Employment status 0.10 0.58 0.01



the primary role that the postural abnormalities associ-ated with the excessive muscle contractions play in thepsychosocial adjustments of all forms of dystonia; focal,segmental, hemi-, and generalized. The effects of disfig-urement on QoL may be understood in light of evidencethat physical appearance has profound implications forinterpersonal interaction and that attractiveness has a“halo” effect on social perception, such that what isbeautiful is also perceived as good.24 The primary role ofbody concept and disfigurement in determining QoL indystonia, together with previous research demonstratingthe major psychosocial impact of physical deformity onthe individual25 suggest that such a “halo” effect ofphysical appearance also extends to self-perception. Thisformulation is also consistent with our finding that theextent of dystonia was a major predictor of QoL andbody concept and that participants with generalized dys-tonia reported poorer QoL than those with focal dystonia.

In contrast to the large number of publications on QoLin movement disorders such as Parkinson’s disease, rel-atively less research has been conducted on QoL indystonia. Nevertheless, the few previous studies on focaldystonia6,8–12 show results that are broadly similar to ourfindings with different types and extents of dystonia. In astudy by Guddex and associates (1999), QoL as mea-sured by the EuroQol and SF36 was significantly worsefor participants with cervical dystonia compared to thenorms for the general population. They also found thatthe extent of dystonia was an important determinant ofQoL and reported that participants with nonfocal dysto-nia had poorer QoL than participants with focal dystonia.Additionally, employment status and age also influencedQoL scores in their sample. Camfield and coworkers(2002) used the SF36 to assess QoL in 289 participantswith cervical dystonia across seven European countries.Their results showed that participants with cervical dys-tonia scored significantly worse on all eight domains ofthe SF36 compared to a cross-section of the generalpopulation of a similar age. In contrast to our findings,they found that QoL scores of participants with cervicaldystonia showed significant effects of age, sex, and ed-ucation. Muller and colleagues (2002) used SF36 toassess QoL in 89 participants with blepharospasm and131 participants with cervical dystonia and showed thatpatients with dystonia scored significantly worse than anage-matched community sample. Of interest, sex differ-ences were found in the blepharospasm group but notcervical dystonia group. Women with blepharospasmscored significantly lower on QoL scales, while men witha long duration of illness had significantly better QoLscores, suggesting some form of adaptation to the illness

over time. Sex differences in QoL in dystonia clearlyrequire further investigation.

In the present study, with a large community-basedsample of focal, segmental, and generalized dystonia, wefound that functional disability, body concept/disfigure-ment, and depression were the most important predictorsof QoL. The importance of depression as a predictor ofQoL in dystonia mirrors previous findings relating toQoL in Parkinson’s disease.26 Previous studies in focaldystonia as well as the present study with various formsof dystonia indicate that younger dystonia participantshad worse QoL than older participants. Younger individ-uals generally lead more active lives than older people,are more socially engaged, and have greater family andwork-related responsibilities. As a result, the interferenceof symptoms of dystonia with their everyday life is likelyto be greater in younger than in older people.

Previous research on cervical dystonia has shown that,although successful treatment of the head deviation andpain with botulinum toxin injections improves depres-sion, it does not alter the negative body concept.27 Giventhe primary contribution of functional disability, bodyconcept/disfigurement, and depression to QoL in dysto-nia, efforts to improve health care for participants withdystonia should therefore not only focus on reducing theseverity of dystonia, but also consider factors critical forgood QoL. Interventions aimed at modifying the nega-tive body concept and the participants sense of disfig-urement may have a large impact on improving QoL indystonia.

While the results of the regression analyses suggestthat functional disability and depression are among theprincipal determinants of QoL in dystonia, it is alsoimportant to note that, by their very nature, QoL mea-sures have some conceptual overlap with measures ofdisability and mood, which could influence findings.Furthermore, although the results of cross-sectional datasuch as these are informative, firmer evidence regardingthe direction of effects between these measures of psy-chosocial functioning would require longitudinal follow-up; which would provide interesting and novel dataabout the evolution of QoL in the course of dystonia. Adisease-specific measure was not available at the time ofour study. A disease-specific measure of QoL has beenrecently developed and validated for dystonia.28 It re-mains a task for future studies to use this disease-specificmeasure to assess QoL in dystonia.

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