Eva Palmquist

Overlap in prevalence between various types of environmental intolerance.

Environmental intolerance (EI) is characterized by attribution of several, multisystem symptoms to specific environmental exposures, such as exposure to odorous/pungent chemicals, certain buildings, electromagnetic fields (EMFs) and everyday sounds. The symptoms are medically unexplained, non-specific and the symptoms overlap between different types of EI. To approach the issue of underlying mechanisms the matter of overlap in prevalence between intolerances can provide valuable information. The aim of the study was to examine if the overlap between intolerance to odorous/pungent chemicals, certain buildings, EMFs and sounds is larger than the expected overlap if no association would exist between them. The study was using cross-sectional data from the Västerbotten Environmental Health Study in Sweden; a large questionnaire-based survey. 8520 adults (18-79 years) were randomly selected after stratification for age and sex, of whom 3406 (40%) participated. Individuals with the four types of intolerance were identified either through self-report, or by having been physician-diagnosed with a specific EI. The overlaps between the four EIs were greater than predictions based on coincidence for both self-reported and diagnosed cases (except for the overlap between diagnosed intolerance to sounds and EMFs). The results raise the question whether different types of EI share similar underlying mechanisms, or at least that the sufferers of EI share some predisposition to acquire the conditions.

Psychometric evaluation and normative data for a Swedish version of the Patient Health Questionnaire 15-Item Somatic Symptom Severity Scale

The lack of an available Swedish version of the Patient Health Questionnaire 15-Item Somatic Symptom Severity Scale (PHQ-15) motivated the present psychometric evaluation of such a version as well as providing normative data for the PHQ-15. Data from 3,406 individuals who took part in the Västerbotten Environmental Health Study in Sweden were used. The respondents constitute a random sample, aged 18 to 79 years, stratified for age and sex. They responded to a Swedish translation of the PHQ-15 as well as the Hospital Anxiety and Depression Scale, the Perceived Stress Scale, and the Shirom Melamed Burnout Questionnaire for assessment of convergent validity. The distribution of PHQ-15 scores was positively skewed and mesokurtic in shape, and the internal consistency of the PHQ-15 was satisfactory. Correlation coefficients between PHQ-15 score and the measures of anxiety, depression, stress and mental/physical exhaustion indicate satisfactory validity. Normative data for PHQ-15 scores as well as for categories of somatic symptom severity are provided. The favorable psychometric properties of the Swedish version of the PHQ-15 suggest use of this instrument for quantification of somatization in Swedish and similar populations, and has the advantage of available normative data.

Psychological distress in asthma and allergy: the Västerbotten Environmental Health Study

With the aim to better understand the association between asthma/allergy and psychological distress, it was hypothesized that levels of stress, exhaustion, anxiety, depression, and health worries for environmental pollution would be higher in allergic asthma, allergic rhinitis, and atopic dermatitis than in non-allergic asthma and in referents without asthma or allergy. Taking part in the population-based Västerbotten Environmental Health Study (aged 18–79 years), 76 respondents reported a physician-based diagnosis of allergic asthma, 86 reported non-allergic asthma, 190 reported allergic rhinitis, and 46 reported atopic dermatitis as the only form of asthma/allergy. A group of 2876 respondents without an asthma/allergy diagnosis constituted as referents. The participants responded to the Perceived Stress Scale, the Shirom-Melamed Burnout Questionnaire, the Hospital Anxiety and Depression Scale, and the Environmental Pollution subscale of the Modern Health Worries Scale. Levels of stress, exhaustion, and anxiety were higher in allergic asthma and atopic dermatitis than in non-allergic asthma, allergic rhinitis, and among referents, and there was a strong tendency of such group differences for depression and health worries. The results imply that stress reduction and treatment of negative affect may in certain cases be fruitful interventions in patients with atopy.

Metric properties and normative data for brief noise and electromagnetic field sensitivity scales

Aims: Lack of brief questionnaire instruments for quantifying affective reactions to and behavioral disruptions attributed to sounds and electromagnetic fields (EMFs) motivated the present development and metric evaluation of such instruments, called the 11-item Noise Sensitivity Scale (NSS-11) and the 11-item Electromagnetic Field Sensitivity Scale (EMFSS-11). Another objective was to establish normative data for these instruments. Method: Data from 3406 individuals who took part in the Västerbotten Environmental Health Study was used. The participants constitute a random sample of inhabitants in the county of Västerbotten in Sweden, aged 18 to 79 years, stratified for age and gender. The participants responded to the NSS-11 and EMFSS-11 and to additional questions for evaluation of concurrent validity. Results: The results show satisfying reliability (Cronbach α = 0.71–0.85, varying with age group and gender), concurrent validity, and unidimensionality of the NSS-11 and EMFSS-11, and that the scales generate scores with approximately normal distributions, irrespective of age group and gender. Mean scores, standard deviations, and confidence intervals constitute normative data. Conclusions: The favorable metric properties of the NSS-11 and EMFSS-11 in combination with their fast usage suggest that they are particularly useful for assessment in epidemiological studies, and have the advantage of available normative data.

Symptom-trigger factors other than allergens in asthma and allergy

Abstract Several environmental exposures of particular relevance for indoor air quality, such as exposure to odorants, may be associated with asthma and allergy. The aim of this study was to investigate attribution of symptoms and behavioral disruptions to various chemical and physical environmental sources in persons with self-reported asthma and allergy. Data from a population-based study, the Västerbotten Environmental Health Study, were used to compare persons with asthma, allergic rhinitis, allergic dermatitis, multiple diagnoses of asthma/allergy and no asthma or allergy. Persons with asthma and multiple diagnoses reported odorous/pungent and building-related environmental factors to trigger symptoms to a larger extent than did the reference group, mainly due to perfume and odors from flowers. They also reported behavioral disruptions and affective reactions to odorous/pungent environments. These findings increase the understanding of the role of odorants in symptom development and thereby the prevention of health problems in asthma and allergy in indoor air.

Coping and Social Support in Asthma and Allergy : The Västerbotten Environmental Health Study

Abstract Objectives: Asthma and allergy are stressful conditions that require coping strategies and social support to reduce stress and enhance health-promoting behavior. However, research is limited regarding coping and social support in asthma and allergy. The aim was to better understand the use of different coping strategies and perceived social support in low and high severity (exacerbation frequency) of asthma and allergy. Methods: Population-based data were used to provide ratings of coping strategies (Study I) and social support (Study II) from 124 and 94 participants, respectively, with asthma and/or allergy, categorized as low or high in severity. Problem- and emotion-focused coping strategies were assessed as well as emotional, instrumental and informative social support from seven sources. Results: Study I showed that avoiding certain environments (problem-based coping) and trying to accept one’s situation (emotion-based) were the most commonly used coping strategies. These behaviors did not differ due to severity. Study II showed that more emotional than instrumental and informative support was perceived. The highest rated support sources were the partner, family members and the healthcare system. More social support was reported in low asthma/allergy severity compared to high asthma/allergy severity. Conclusion: The most commonly used coping strategies in the population of persons with these four types of asthma and allergy are avoiding certain environments and trying to accept one’s situation. More emotional support than instrumental and informative is perceived to be received, and most of the support is received from one’s partner and other family members and least from authorities and patient associations/support groups.

Comorbidity and Multimorbidity of Asthma and Allergy and Intolerance to Chemicals and Certain Buildings

Objectives: We tested the hypothesis of high comorbidity between asthma/allergy and chemical intolerance (CI) and between asthma/allergy and building intolerance (BI), and high multimorbidity between asthma/allergy, CI, and BI. Methods: Population-based questionnaire data were used from 530 participants with asthma/allergy (allergic asthma, nonallergic asthma, allergic rhinitis, and/or atopic dermatitis), 414 with self-reported and 112 with physician-diagnosed CI, and 165 with self-reported and 47 with physician-diagnosed BI. Separate reference groups were formed for each of the five case groups. Results: Adjusted odds ratios varied from 4.6 to 13.1 for comorbidity, and from 6.6 to 46.4 for multimorbidity. Conclusion: The large comorbidity and multimorbidity between asthma/allergy, CI, and BI evokes the question as to whether there are similarities in underlying mechanisms between these conditions.

Psychological symptoms and health-related quality of life in idiopathic environmental intolerance attributed to electromagnetic fields

OBJECTIVE Need for better understanding of the etiology of idiopathic environmental intolerance attributed to electromagnetic fields (IEI-EMF) motivated the present study of psychological symptoms and health-related quality of life (HRQoL) in person who attribute health problems to electromagnetic fields. METHODS Participants with IEI-EMF (n=114) and a population-based sample of referents (n=104) were investigated with six subscales of the Symptom Checklist 90 (SCL-90) to assess psychological symptoms, and with eight subscales of the Short Form (36) Health Survey (SF-36) to assess HRQoL. RESULTS Significantly higher scores were found on obsessive/compulsive behavior, interpersonal hypersensitivity, hostility, phobic anxiety, paranoid thoughts in the IEI-EMF group compared to referents, whereas only a tendency of such a difference was found for psychotism. Furthermore, poorer HRQoL in the IEI-EMF group, compared to referents, were found regarding physical and social functioning, physical and emotional role limitations, general health, vitality, bodily pain, and mental health. Significant correlation with moderate to strong effect sizes were found between several of the SCL-90 and SF-36 subscales. CONCLUSION The results suggest that IEI-EMF is associated with various types of psychological symptoms and with poor HRQoL. Clinical implications include theoretical support for cognitive behavioral therapy, and, although further research is needed, that attention should be directed towards feelings of inferiority and uneasiness in relationships as well as anger, hostility and resentment towards other people.

Prevalence of various environmental intolerances in a Swedish and Finnish general population

Objective: To determine the prevalence of various environmental intolerances (EIs), using several criteria in a Swedish and a Finnish general population. Ill‐health attributed to low‐level environmental exposures is a commonly encountered challenge in occupational and environmental medicine. Methods: In population‐based questionnaire surveys, the Västerbotten Environmental Health Study (Sweden) and the Österbotten Environmental Health Study (Finland), EI was inquired by one‐item questions on symptom attribution to chemicals, certain buildings, or electromagnetic fields (EMFs), and difficulties tolerating sounds. The respondents were asked whether they react with central nervous system (CNS) symptoms or have a physician‐diagnosed EI attributed to the corresponding exposures. Prevalence rates were determined for different age and sex groups and the Swedish and Finnish samples in general. Results: In the Swedish sample (n = 3406), 12.2% had self‐reported intolerance to chemicals, 4.8% to certain buildings, 2.7% to EMFs, and 9.2% to sounds. The prevalence rates for the Finnish sample (n = 1535) were 15.2%, 7.2%, 1.6%, and 5.4%, respectively, differing statistically significantly from the Swedish. EI to chemicals and certain buildings was more prevalent in Finland, while EI to EMFs and sounds more prevalent in Sweden. The prevalence rates for EI with CNS‐symptoms were lower and physician‐diagnosed EIs considerably lower than self‐reported EIs. Women reported EI more often than men and the young (18–39 years) to a lesser degree than middle‐aged and elderly. Conclusions: The findings reflect the heterogeneous nature of EI. The differences in EI prevalence between the countries might reflect disparities concerning which exposures people perceive harmful and focus their attention to. HIGHLIGHTSThe prevalence of various types of EI is country‐dependent.The results imply that societal factors contribute to EI.The prevalence of EI with CNS symptoms is lower than self‐reported EI.Recognition of EI gives opportunities to hinder the progression of the condition.The prevalence rates for building‐related intolerance have previously been lacking.

Intolerance to environmental chemicals and sounds in irritable bowel syndrome: Explained by central sensitization?:

This study tested the hypotheses of irritable bowel syndrome showing (1) comorbidity with chemical and sound intolerance, other types of functionally somatic syndromes, and psychiatric disorders and (2) stronger than normal affective reactions to and behavioral disruptions from odorous/pungent chemicals and sounds in daily life. These hypotheses were tested by means of data from a large-scale population-based questionnaire study. The results showed comorbidity in irritable bowel syndrome with chemical and sound intolerance, fibromyalgia, migraine, post-traumatic stress disorder, generalized anxiety disorder, panic syndrome, and depression as well as strong reactions/disruptions from odorous/pungent chemicals and sounds in irritable bowel syndrome.