Satakunta Central Hospital and Turku University Hospital Were Reviewe
Introduction
Psychiatric comorbidities are more frequent in persons suffering from headache compared to headache-gratuitous persons and in large population-based studies low and anxiety associated both with migraine and with other headaches.ane,two Also stress and hostility are more mutual in a headache population.three–5 The relationship of depression and anxiety with headache is idea to exist bidirectional particularly in migraine patients, ie low increases headache symptoms and headache, if frequent, causes low.six Considering psychiatric symptoms are common in headache patients, it is important to have as well the mental factors into business relationship when assessing the burden of headache and the handling of headache patients. The headache population in general and occuptional practice is more likely to exist mildly affected compared to patients attending specialist clinics. Even though the former grouping of patients might limited mental symptoms, such every bit anxiety, when seeking medical help for pain, information technology is important to straight the clinical investigation and treatment towards the headache. In headache, as in other hurting syndromes, ane of the chief targets is to prevent the condition from becoming chronic.
The headache bear upon test-half dozen (Hit-6) is a brief and widely used questionnaire to appraise headache severity and headache-related disability.seven–9 It is a validated, self-administered six-particular questionnaire, consisting of items for hurting intensity, social operation, part functioning, vitality, cerebral functioning, and psychological distress.7 The Striking-6 is suitable for daily exercise to screen headache patients needing special attention regarding treatment.10 It can likewise exist used in clinical research to measure long-term treatment response.11,12
The Striking-6 has been translated into more than 20 languages, including Finnish.13,fourteen However, item scale correlation of the Hit-6 particular 3 in the Finnish translation was weak due to identified translation issues.15 The Hit-6 has been validated in different headache populations using other headache and quality of life questionnaires.10,16,17 The Hit-half dozen has as well been used as a reference in validation of feet questionnaires.18 Furthermore, correlation of the Hitting-6 score with the severity of depression and correlation of low with psychosocial parameters in headache patients have been reported.nine,19
To our noesis, this is the beginning study to assess the relation of individual Hit-6 items with psychosocial factors, anxiety, depression, stress, social isolation and hostility in a female person working-aged population. The aim of the nowadays study is to assess how in a female population psychosocial take chances factors correlate with Hitting-six, as well as to evaluate the usefulness of the HIT-six questionnaire in occupational health care.
Material and methods
Written report population
The subjects for this written report were enrolled from the PORTAAT (Pori to Aid Against Threats) study population comprising employees of the city of Pori (83,500 inhabitants) in southwestern Republic of finland during 2014–2015.xx The study population included workers from 10 work units selected by the master of the welfare unit of Pori. Invitation and study information messages were sent to the employees every bit an email attachment past the managers of the work units. Librarians, museum employees, groundkeepers, computer workers, social workers, nurses, physicians, authoritative officials, and general office staff were invited to an enrollment date with the report nurse. Birthday 836 employees (732 females, 104 males) consented to participate in the PORTAAT report. For this subanalysis, nosotros included a total of 469 females, who had consummate data concerning psychosocial risk factors and who answered "yes" to the question "Take yous had headache during the past year?" which is the ballast question for the Hitting-6 questionnaire. The verbal headache diagnosis of the women was non known.
Demographic and lifestyle data
Demographic and lifestyle data were collected using self-administered questionnaires. Their comprehensiveness was tested in a group of volunteers. Questions assessed marital status ("cohabiting or not"), smoking ("electric current smoker, non-smoking", divers as having never smoked or having quit smoking >12 months ago), years of education, quality of slumber ("adept" or "not good") and alcohol consumption (the 3-item alcohol use disorders identification examination, Audit-C).21 Financial satisfaction was assessed with the question "Practice y'all have to save on expenditures?" ("yes" or "no"). Leisure-time physical activity (LTPA) was classified as follows: high: LTPA for ≥30 minutes at a time, four or more than times a calendar week; moderate: LTPA for ≥xxx minutes at a time, two to three times a calendar week; low: LTPA for ≥thirty minutes at a time for a maximum of once a week. Quality of life was assessed using the EuroQol questionnaire (EQ-5D), which comprises 5 dimensions of wellness: mobility, self-care, usual activities, pain/discomfort and anxiety/depression.22 The level of the problem on each dimension can be reported every bit "no", "moderate" or ''extreme" problems. These health states may exist converted into a single summary index past applying the choice-based method of the time merchandise-off using the UK'due south general population.23 The number of days on sick go out due to any sort of pain was measured by asking "How many days of work have you missed (sick leave) considering of pain during the by 12 months?".
Trained study nurses measured superlative, weight and blood pressure of each subject. Body mass index (BMI) was calculated every bit weight (kg) divided by tiptop squared (m2).
The HIT-half dozen questionnaire
The Hit-6 is a six-item, cocky-administered questionnaire including 3 questions assessing headache during the by 4 weeks and 3 questions about headaches with no time limit.7 The construct validity of the HIT-6 questionnaire is good and it has been establish to have good internal consistency (Cronbach's α =0.90) and exam-retest reliability (Cronbach's α =0.78).7 Striking-6 questions concern the following items: (1) frequency of severe pain; (ii) ability to practise usual daily acitivities; (3) need to prevarication down; (4) tiredness; (v) irritation; and (6) ability to concentrate.8 The Hit-6 is scored by giving a value for each question (never=vi, rarely=8, sometimes=10, very often=eleven and always=13). The full score is the sum of the scores on all six questions. On the basis of the total score, the Hit-6 categorizes patients into four levels of headache impact: footling or no bear upon (<50), some impact (l–55), substantial impact (56–59) and very severe impact (≥lx).
The study subjects filled in the new Finnish version of the HIT-6 questionnaire, which was produced by the frontward-backward translation process.13 A new Finnish translation was washed, because of problems in the earlier Finnish version of HIT-half dozen.15 Translation from English to Finnish was beginning performed by v native speakers of Finnish fluent in English language. A native English speaker fluent in Finnish and previously unfamiliar with the Hitting-6 translated this Finnish translation back to English. This translation was compared to the original English HIT-6 for conceptual equivalence. The new Finnish translation was performed without the approval of OptumInsight Life Sciences (QualityMetrics), notwithstanding, a retroactive license has since been issued.
Questionnaires for psychosocial risk factors
Psychosocial risk factors, anxiety, low, social isolation, hostility and work stress were assessed using standardized cocky-administered questionnaires. Considering the PORTAAT study analyses mainly cardiovascular risk factors, the psychosocial take chances factors for the present written report were selected according to the European 2012 guidelines on cardiovascular affliction prevention in clinical practice.24
Anxiety
Anxiety was assessed by the generalized anxiety disorder 7-item scale (GAD-seven) . The total score ranges from 0 to 21; 0–four= no or little feet, 5–9= some anxiety, 10–15= substantial anxiety and 16–21= severe anxiety; score of ten or more has 89% sensitivity and 82% specificity for generalized anxiety.25
Depression
Low was assessed using the major depression inventory (MDI).26 The MDI is a cocky-rated questionnaire consisting of 10 items. It measures depressive symptoms during the by 2 weeks on a half dozen-bespeak Likert-type scale from 0= never to 5= all the time. The total score ranges from 0 to 50, a high score indicating a loftier number of depressive symptoms, and the optimal cut-off score of 26 indicating major (moderate to severe) low.
Social isolation
Social isolation was studied using the ENRICHD short social support musical instrument (ESSI).27 The ESSI is composed of six items estimating the amount of received social support with a 5-point Likert-type scale from 0=never to 4=always. The total score range is 0 to 24, a lower score indicating higher level of social isolation. This is the beginning report to use this questionnaire in a headache population.
Hostility
Hostility was measured using the cynical distrust self-administered questionnaire (cynical distrust scale) consisting of 8 items rated on a v-point Likert scale from completely disagree to completely agree.28 The total score range is viii to 32, a lower score indicating a higher level of hostility. This is the first study to use this questionnaire in a headache population.
Piece of work stress
Work stress was evaluated by the Finnish Bergen Burnout Indicator (BBI-15).29 The BBI-15 measures occupational burnout using 15 questions. The answers are given using Likert-blazon scales from 1 to 6 (1= completely disagree to half dozen= completely agree), that are summed up to score from 15 to xc, a loftier score indicating a high level of work stress. This is the first study to utilize this questionnaire in a headache population.
Statistical analysis
The characteristics of the study population are presented equally ways with SD or equally medians with IQR or as counts with percentages. Internal consistency was estimated by computing Cronbach'due south alpha internal consistency with bias corrected bootstrap and 95%CI. An exploratory factor analysis with the iterated principal-factor method for factoring and promax-rotated factor loadings on polychoric correlation matrix was performed to place related items in the HIT-6 questionnaire. Promax rotation is an culling nonorthogonal rotation method. The strategies used to extract the number of factors were: the Kaiser criteria, which determine that components with eigenvalues lower than one should exist excluded and the screen examination of Cattell criteria. Item analysis of the Hitting-six scales was performed past analyzing item discriminating power (corrected item correlation) and detail difficulty (item hateful) depicted by the exploratory data analysis. Corrected detail correlation was estimated using polyserial correlations. Adjusted correlation (partial) coefficients of Hit-six and psychosocial factors were calculated past the Pearson method, using Sidak adapted probabilities. Correlation coefficients less than 0.twenty were considered very weak, between 0.20 and 0.39 weak, between 0.40 and 0.59 moderate, betwixt 0.60 and 0.79 strong, and above 0.79 very strong.30 Multivariate regression analyses were used to identify the psychosocial factors of the Hit-half-dozen using standardized regression coefficients beta (β). The β value is a measure of how strongly each predictor variable influences the benchmark (dependent) variable. The β is measured in units of standard deviation. Cohen's standard for β values above 0.10, 0.30 and 0.fifty represent pocket-sized, moderate and big relationships, respectively. The floor and ceiling values representing the percentages of the females, who obtained the lowest or highest scores, were calculated for each HIT-vi item separately. The floor and ceiling furnishings are considered to be nowadays if more than xv% of the respondents attain the everyman or highest possible scores.31 Statistical significance was gear up a priori at P<0.05. All statistical analyses were carried out with Stata, version fifteen.0 (StataCorp, College Station, TX, USA).
Results
We evaluated 469 female employees, who had suffered from headache during the by year. The baseline characteristics of the subjects are shown in Table 1. Figure i shows the distribution of the Hit-half dozen scores in the study population. The mean (SD) of the Hit-half dozen score was 48 (8), range 36–68.
 | Table 1 Characteristics of the 469 report subjects |
 | Effigy 1 Histogram of the Striking-6 total scores in the report population. Box-and-whiskers plot shows median and IQR, and whiskers indicate 5th and 95th percentiles. Dotted lines show the HIT-6 categories (headache bear on): lilliputian or no impact (score <50), some touch (fifty–55), substantial impact (56–59) and severe impact (≥60). Abbreviation: Hit-6, headache touch on examination-6. |
All study subjects responded to all six HIT-half dozen items. Tabular array two shows the mean scores (SD) of the items and the flooring and ceiling furnishings. The floor event was clearest in the questions concerning the bear on of headache on the quality of life (items 4 to 6).
 | Tabular array ii Mean scores (SD) of the HIT-6 items in study population and flooring and ceiling effects |
Exploratory factor assay of the HIT-vi scores revealed two factors; factor 1 (items 4 to six) describes quality of life and psychological aspects affected past headache, and cistron ii (items 1 to 3) severity of headache and functional reject (Table 3). These factors explained 95% of the total variance. Significant positive correlation between factor i and factor 2 was detected (r=0.58, 95%CI: 0.51–0.64).
 | Table 3 Exploratory factor analysis with promax-rotated factor loadings of the Hitting-6 items. Coefficients with values <0.40 non shown |
Detail analysis of the HIT-6 showed that all items had a skillful overall item correlation (Effigy two). Items 1 and 3 (severity of headache and functional reject) showed the highest mean values. Internal consistency of the HIT-6 was (Cronbach's α coefficient) 0.87 (95%CI: 0.85–0.89).
 | Figure ii Item assay for the HIT-6 items. The line denotes total hateful of all items. Numbers indicate respective items in the HIT-6. Abbreviation: Hit-half-dozen, headache bear upon examination-6. |
Correlations betwixt the HIT-vi gene 1, Striking-six factor 2 and psychosocial factors adjusted for age and educational activity years are shown in Table 4. Adjustment for age and education was fabricated because both variables affect the incidence of headache.32,33
 | Table 4 Correlations betwixt the HIT-half dozen and psychosocial factors (adapted by age and education years) |
A statistically significant positive correlation was found between the HIT-half-dozen total score and low, anxiety and stress and a statistically significant negative correlation between Striking-6 total score and social isolation. The Hitting-6 cistron 1 (quality of life and psychological aspects affected past headache) had a statistically significant positive correlation with depression and feet and a negative correlation with social isolation. In turn, the Hit-vi factor two (hurting severity and intensity) had statistically significant positive correlation with anxiety, low and stress. There were no statistically significant relationships betwixt the total HIT-vi score and psychosocial factors (Effigy 3).
 | Figure 3 Multivariate relationships between the full HIT-6 score and psychosocial factors (β-values with 95% confidence intervals). Dotted line shows small (beta 0.10) magnitude of effect size. Abbreviations: GAD-7, generalized anxiety disorder 7-item scale; MDI, major depression inventory; ESSI, ENRICHD brusk social support instrument; CDS, cynical distrust scale; BBI-xv, Bergen burnout indicator; Hit-6, headache touch on test-6. |
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Our study showed that apart from hostility, the correlations of the HIT-six total score with all measured psychosocial risk factors were weak, although statistically significant. This implies that in occupational health care the HIT-six specifically describes the impact of headache without existence confounded by psychosocial factors in a female population. Our report too indicated that the HIT-6 questionnaire can exist divided into two factors: cistron i describing the psychological stress and impaired quality of life and factor 2 expressing the intensity of and the physical deterioration caused by headache. The Hitting-6 item discriminatory power was good and the factorial nature of the questionnaire became evident in the item analysis.
In the present report a flooring effect was observed for both factors ane and two. It was strong for factor 1 describing psychological effects and impaired quality of life. This was expected, because our report population consisted of females with preserved work power and without prominent bug or functional decline caused by headache. In contrast, factor two showed less flooring upshot and, therefore, a larger variety of hurting intensity and impairment of functionality.
According to before studies the HIT-half-dozen is viable in general do.10 Our written report supports before Hit-6 validation studies showing that the new Finnish version of Hit-6 reliably measures the burden of headache. On the ground of earlier studies we know that feet, depression and stress are common in headache patients and that they increase the affect of headache and impair daily functioning.34 There are only a few studies correlating the Hitting-6 with psychological hazard factors but no previous studies accept assessed the relation of individual Hit-6 items with psychosocial factors.ix,sixteen,19,35 These studies show that patients with higher HIT-six scores have higher depression scores. Breslau et al reported that the correlation betwixt headache and depression is bidirectional; patients with more headaches are decumbent to low and depressed patients are prone to accept more headaches.six The evidence of a relationship between depression and other headaches has also been documented.xix Our study shows that in a female occupational population the Hit-six (ie impact of headache) correlates only weakly, simply statistically significantly, with the psychosocial factors. This denotes that the Hit-6 focuses on the brunt caused by headache per se, which is of import in selecting appropriate handling options.
In the present study, hostility was the but psychosocial factor lacking correlation with the Hit-6 items. The significance of this observation remains obscure and is complicated by the fact that hostility has been primarily defined for research purposes and not routinely used in clinical evaluation.
The force of our study is that the study population was well characterized and consisted of a relatively big cohort of female person employees. The questionnaires used to measure psychosocial risk factors are valid and reliable. The new translation of the Finnish Striking-6 questionnaire was produced and validated according to recommendations.xiii Although there was some variability in occupational tasks, our study population consisted of employees having a relatively homogeneous cultural groundwork. Only female employees were included in this substudy, considering the total number of males in the PORTAAT study was depression from the showtime and only a few men had headache. Sectional enrollment of female participants also contributed to the homogeneity of the study population and the reliability of the results. This is important because psychosocial take a chance factors and headache characteristics are different in women and men.36
A limitation of the study was that nosotros did not know the exact diagnoses of headache in our study population. However, this should not significantly affect our conclusions, since the Striking-six has been validated in many different headache populations. Because of the inclusion criteria, females with few headaches in the past year and probably just few females with chronic headache were included in the study. This might skew the results and underestimate the impact of psychiatric symptoms. Future studies are needed to gauge the interrelationship of HIT-vi items and psychosocial risk factors in specific headache populations, eg episodic migraineurs and chronic headache patients.
There was no substantial psychological brunt or impairment in quality of life in our study population consisting of females with preserved work power. This raises the question of whether the correlation between HIT-6 and psychosocial take chances factors would be different in a disabled population, eg those with chronic tension blazon headache or chronic migraine. Farther studies are warranted to ascertain how psychosocial factors impact the HIT-half-dozen scores in females with disabling headache.
Conclusion
Our report shows that the HIT-half-dozen has good construct validity in a female occupational population, and that its items can be divided into two factors, which describe dissever categories of headache affect: the hurting itself and its psychological impact. In our study population the correlations betwixt the HIT-6 total score and all psychosocial risk factors measured (except for hostility) were weak, but statistically significant. This indicates that, in female person employees, the HIT-6 questionnaire measures specifically the impact of headache without distortion by psychosocial factors. In general and occupational do a loftier HIT-6 score indicates the need to actively treat the headache, based on right headache diagnosis and etiologic targeting of the therapy.
Upstanding approval and consent to participate
The report protocol and consent forms were reviewed and approved by the Ideals Committee of the Infirmary Commune of Southwestern Finland. All participants provided written informed consent for the projection and subsequent medical inquiry.
Acknowledgments
The authors give thanks Dr Mikko Kuoppamäki for his critical review of the manuscript and Mrs Jacqueline Välimäki for language audit. Unrestricted enquiry grants from the Common Insurance Company Etera and the Finnish Cultural Foundation are gratefully acknowledged. The work was also supported by the Central Satakunta Health Federation of Municipalities.
Writer contributions
All authors participated in planning the study. Kirsi Malmberg-Ceder and Päivi Due east Korhonen collected the data. Hannu Kautiainen carried out the statistical analyses. All authors contributed toward data assay, drafting and critically revising the newspaper, gave final blessing of the version to exist published, and concur to be accountable for all aspects of the work.
Disclosure
Maija Haanpää reports personal fees from Abbvie, Astellas, and Pfizer, exterior the submitted work. The other authors report no conflicts of involvement in this work.
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Source: https://www.dovepress.com/the-role-of-psychosocial-risk-factors-in-the-burden-of-headache-peer-reviewed-fulltext-article-JPR
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