Wilma L. Zijlema

How to assess common somatic symptoms in large-scale studies: A systematic review of questionnaires

OBJECTIVE Many questionnaires for assessment of common somatic symptoms or functional somatic symptoms are available and their use differs greatly among studies. The prevalence and incidence of symptoms are partially determined by the methods used to assess them. As a result, comparison across studies is difficult. This article describes a systematic review of self-report questionnaires for somatic symptoms for use in large-scale studies and recommends two questionnaires for use in such studies. METHODS A literature search was performed in the databases Medline, PsycINFO and EMBASE. Articles that reported the development, evaluation, or review of a self-report somatic symptom measure were included. Instrument evaluation was based on validity and reliability, and their fitness for purpose in large scale studies, according to the PhenX criteria. RESULTS The literature search identified 40 questionnaires. The number of items within the questionnaires ranged from 5 to 78 items. In 70% of the questionnaires, headaches were included, followed by nausea/upset stomach (65%), shortness of breath/breathing trouble (58%), dizziness (55%), and (low) back pain/backaches (55%). Data on validity and reliability were reported and used for evaluation. CONCLUSION Questionnaires varied regarding usability and burden to participants, and relevance to a variety of populations and regions. Based on our criteria, the Patient Health Questionnaire-15 and the Symptom Checklist-90 somatization scale seem the most fit for purpose for use in large-scale studies. These two questionnaires have well-established psychometric properties, contain relevant symptoms, are relatively short, and are available in multiple languages.

Mood and Anxiety Disorders in Chronic Fatigue Syndrome, Fibromyalgia, and Irritable Bowel Syndrome : Results From the LifeLines Cohort Study

Objective Functional somatic syndromes (FSSs) have often been linked to psychopathology. The aim of the current study was to compare prevalence rates of psychiatric disorders among individuals with chronic fatigue syndrome (CFS), fibromyalgia (FM), and irritable bowel syndrome (IBS). Methods This study was conducted in 94,516 participants (mean [standard deviation] age = 44.6 [12.5] years, 58.7% women) of the general-population cohort LifeLines. FSSs were assessed by self-reports. Mood disorders (i.e., major depressive disorder and dysthymia) and anxiety disorders (i.e., generalized anxiety disorder, social phobia, panic disorder with/without agoraphobia, and agoraphobia) were assessed by means of the Mini International Neuropsychiatric Interview. Risks on psychiatric disorders were compared for individuals with CFS, FM, and IBS by using logistic regression analyses adjusted for age and sex. Results Prevalence rates of CFS, FM, and IBS were 1.3%, 3.0%, and 9.7%, respectively. Individuals with CFS, FM, and IBS had significantly more mood (odds ratios [ORs] = 1.72–5.42) and anxiety disorders (ORs = 1.52–3.96) than did individuals without FSSs, but prevalence rates were low (1.6%–28.6%). Individuals with CFS more often had mood (ORs = 2.00–4.08) and anxiety disorders (ORs = 1.63–2.32) than did individuals with FM and IBS. Major depressive disorder was more common in FM than in IBS (OR = 1.58, 95% confidence interval = 1.24–2.01), whereas these groups did not differ on dysthymia or anxiety disorders. Conclusions Mood and anxiety disorders are more prevalent in individuals with FSSs, and particularly CFS, than in individuals without FSSs. However, most individuals with FSSs do not have mood or anxiety disorders.

The association of air pollution and depressed mood in 70,928 individuals from four European cohorts

BACKGROUND Exposure to ambient air pollution may be associated with impaired mental health, including depression. However, evidence originates mainly from animal studies and epidemiological studies in specific subgroups. We investigated the association between air pollution and depressed mood in four European general population cohorts. METHODS Data were obtained from LifeLines (the Netherlands), KORA (Germany), HUNT (Norway), and FINRISK (Finland). Residential exposure to particles (PM2.5, PM2.5absorbance, PM10) and nitrogen dioxide (NO2) was estimated using land use regression (LUR) models developed for the European Study of Cohorts for Air Pollution Effects (ESCAPE) and using European wide LUR models. Depressed mood was assessed with interviews and questionnaires. Logistic regression analyses were used to investigate the cohort specific associations between air pollution and depressed mood. RESULTS A total of 70,928 participants were included in our analyses. Depressed mood ranged from 1.6% (KORA) to 11.3% (FINRISK). Cohort specific associations of the air pollutants and depressed mood showed heterogeneous results. For example, positive associations were found for NO2 in LifeLines (odds ratio [OR]=1.34; 95% CI: 1.17, 1.53 per 10 μg/m(3) increase in NO2), whereas negative associations were found in HUNT (OR=0.79; 95% CI: 0.66, 0.94 per 10 μg/m(3) increase in NO2). CONCLUSIONS Our analyses of four European general population cohorts found no consistent evidence for an association between ambient air pollution and depressed mood.

Long-term exposure to road traffic noise, ambient air pollution, and cardiovascular risk factors in the HUNT and lifelines cohorts

Aims Blood biochemistry may provide information on associations between road traffic noise, air pollution, and cardiovascular disease risk. We evaluated this in two large European cohorts (HUNT3, Lifelines). Methods and results Road traffic noise exposure was modelled for 2009 using a simplified version of the Common Noise Assessment Methods in Europe (CNOSSOS-EU). Annual ambient air pollution (PM10, NO2) at residence was estimated for 2007 using a Land Use Regression model. The statistical platform DataSHIELD was used to pool data from 144 082 participants aged ≥20 years to enable individual-level analysis. Generalized linear models were fitted to assess cross-sectional associations between pollutants and high-sensitivity C-reactive protein (hsCRP), blood lipids and for (Lifelines only) fasting blood glucose, for samples taken during recruitment in 2006-2013. Pooling both cohorts, an inter-quartile range (IQR) higher day-time noise (5.1 dB(A)) was associated with 1.1% [95% confidence interval (95% CI: 0.02-2.2%)] higher hsCRP, 0.7% (95% CI: 0.3-1.1%) higher triglycerides, and 0.5% (95% CI: 0.3-0.7%) higher high-density lipoprotein (HDL); only the association with HDL was robust to adjustment for air pollution. An IQR higher PM10 (2.0 µg/m3) or NO2 (7.4 µg/m3) was associated with higher triglycerides (1.9%, 95% CI: 1.5-2.4% and 2.2%, 95% CI: 1.6-2.7%), independent of adjustment for noise. Additionally for NO2, a significant association with hsCRP (1.9%, 95% CI: 0.5-3.3%) was seen. In Lifelines, an IQR higher noise (4.2 dB(A)) and PM10 (2.4 µg/m3) was associated with 0.2% (95% CI: 0.1-0.3%) and 0.6% (95% CI: 0.4-0.7%) higher fasting glucose respectively, with both remaining robust to adjustment for air/noise pollution. Conclusion Long-term exposures to road traffic noise and ambient air pollution were associated with blood biochemistry, providing a possible link between road traffic noise/air pollution and cardio-metabolic disease risk.

Ambient air pollution, traffic noise and adult asthma prevalence: a BioSHaRE approach

We investigated the effects of both ambient air pollution and traffic noise on adult asthma prevalence, using harmonised data from three European cohort studies established in 2006–2013 (HUNT3, Lifelines and UK Biobank). Residential exposures to ambient air pollution (particulate matter with aerodynamic diameter ≤10 µm (PM10) and nitrogen dioxide (NO2)) were estimated by a pan-European Land Use Regression model for 2007. Traffic noise for 2009 was modelled at home addresses by adapting a standardised noise assessment framework (CNOSSOS-EU). A cross-sectional analysis of 646 731 participants aged ≥20 years was undertaken using DataSHIELD to pool data for individual-level analysis via a “compute to the data” approach. Multivariate logistic regression models were fitted to assess the effects of each exposure on lifetime and current asthma prevalence. PM10 or NO2 higher by 10 µg·m−3 was associated with 12.8% (95% CI 9.5–16.3%) and 1.9% (95% CI 1.1–2.8%) higher lifetime asthma prevalence, respectively, independent of confounders. Effects were larger in those aged ≥50 years, ever-smokers and less educated. Noise exposure was not significantly associated with asthma prevalence. This study suggests that long-term ambient PM10 exposure is associated with asthma prevalence in western European adults. Traffic noise is not associated with asthma prevalence, but its potential to impact on asthma exacerbations needs further investigation. Long-term ambient PM10 exposure is associated with asthma prevalence in three European adult cohorts http://ow.ly/En4b3049S7X

The relationship between natural outdoor environments and cognitive functioning and its mediators

Background: Urban residents may experience cognitive fatigue and little opportunity for mental restoration due to a lack of access to nature. Natural outdoor environments (NOE) are thought to be beneficial for cognitive functioning, but underlying mechanisms are not clear. Objectives: To investigate the long‐term association between NOE and cognitive function, and its potential mediators. Methods: This cross‐sectional study was based on adult participants of the Positive Health Effects of the Natural Outdoor Environment in Typical Populations in Different Regions in Europe (PHENOTYPE) project. Data were collected in Barcelona, Spain; Doetinchem, the Netherlands; and Stoke‐on‐Trent, United Kingdom. We assessed residential distance to NOE, residential surrounding greenness, perceived amount of neighborhood NOE, and engagement with NOE. Cognitive function was assessed with the Color Trails Test (CTT). Mediation analysis was undertaken following Baron and Kenny. Results: Each 100 m increase in residential distance to NOE was associated with a longer CTT completion time of 1.50% (95% CI 0.13, 2.89). No associations were found for other NOE indicators and cognitive function. Neighborhood social cohesion was (marginally) significantly associated with both residential distance to NOE and CTT completion time, but no evidence for mediation was found. Nor were there indications for mediation by physical activity, social interaction with neighbors, loneliness, mental health, air pollution worries, or noise annoyance. Conclusions: Our findings provide some indication that proximity to nature may benefit cognitive function. We could not establish which mechanisms may explain this relationship. HighlightsWe investigated multiple indicators of natural outdoor environment exposure and cognition.Greater distance to natural outdoor environments was associated with lower cognitive function.Mediation was evaluated, but mechanisms explaining this relationship could not be established.There were no associations for other natural outdoor environment exposure indicators and cognition.

Road traffic noise, blood pressure and heart rate : Pooled analyses of harmonized data from 88,336 participants

INTRODUCTION Exposure to road traffic noise may increase blood pressure and heart rate. It is unclear to what extent exposure to air pollution may influence this relationship. We investigated associations between noise, blood pressure and heart rate, with harmonized data from three European cohorts, while taking into account exposure to air pollution. METHODS Road traffic noise exposure was assessed using a European noise model based on the Common Noise Assessment Methods in Europe framework (CNOSSOS-EU). Exposure to air pollution was estimated using a European-wide land use regression model. Blood pressure and heart rate were obtained by trained clinical professionals. Pooled cross-sectional analyses of harmonized data were conducted at the individual level and with random-effects meta-analyses. RESULTS We analyzed data from 88,336 participants, across the three participating cohorts (mean age 47.0 (±13.9) years). Each 10dB(A) increase in noise was associated with a 0.93 (95% CI 0.76;1.11) bpm increase in heart rate, but with a decrease in blood pressure of 0.01 (95% CI -0.24;0.23) mmHg for systolic and 0.38 (95% CI -0.53; -0.24) mmHg for diastolic blood pressure. Adjustments for PM10 or NO2 attenuated the associations, but remained significant for DBP and HR. Results for BP differed by cohort, with negative associations with noise in LifeLines, no significant associations in EPIC-Oxford, and positive associations with noise >60dB(A) in HUNT3. CONCLUSIONS Our study suggests that road traffic noise may be related to increased heart rate. No consistent evidence for a relation between noise and blood pressure was found.

(Un)Healthy in the City: Respiratory, Cardiometabolic and Mental Health Associated with Urbanity.

Background Research has shown that health differences exist between urban and rural areas. Most studies conducted, however, have focused on single health outcomes and have not assessed to what extent the association of urbanity with health is explained by population composition or socioeconomic status of the area. Our aim is to investigate associations of urbanity with four different health outcomes (i.e. lung function, metabolic syndrome, depression and anxiety) and to assess whether these associations are independent of residents’ characteristics and area socioeconomic status. Methods Our study population consisted of 74,733 individuals (42% males, mean age 43.8) who were part of the baseline sample of the LifeLines Cohort Study. Health outcomes were objectively measured with spirometry, a physical examination, laboratory blood analyses, and a psychiatric interview. Using multilevel linear and logistic regression models, associations of urbanity with lung function, and prevalence of metabolic syndrome, major depressive disorder and generalized anxiety disorder were assessed. All models were sequentially adjusted for age, sex, highest education, household equivalent income, smoking, physical activity, and mean neighborhood income. Results As compared with individuals living in rural areas, those in semi-urban or urban areas had a poorer lung function (β -1.62, 95% CI -2.07;-1.16), and higher prevalence of major depressive disorder (OR 1.65, 95% CI 1.35;2.00), and generalized anxiety disorder (OR 1.58, 95% CI 1.35;1.84). Prevalence of metabolic syndrome, however, was lower in urban areas (OR 0.51, 95% CI 0.44;0.59). These associations were only partly explained by differences in residents’ demographic, socioeconomic and lifestyle characteristics and socioeconomic status of the areas. Conclusions Our results suggest a differential health impact of urbanity according to type of disease. Living in an urban environment appears to be beneficial for cardiometabolic health but to have a detrimental impact on respiratory function and mental health. Future research should investigate which underlying mechanisms explain the differential health impact of urbanity.

Air pollution exposure is associated with restrictive ventilatory patterns

Exposure to ambient air pollution is associated with a substantial burden of morbidity and mortality worldwide [1]. In a recent paper, Adam et al. [2] showed significantly impaired levels of forced expiratory volume in 1 s (FEV1) and forced vital capacity (FVC) associated with exposure to the ambient air pollutants nitrogen dioxide (NO2) and particles with a 50% cut-off aerodynamic diameter of 10 μm (PM10) in 7613 adults included in the European Study of Cohorts for Air Pollution Effects (ESCAPE). Effect estimates for FVC were of similar magnitude (for NO2) or larger (for PM10) than those for FEV1. In line with these findings, Forbes et al. [3] showed negative associations of PM10 and NO2 with the level of FEV1 in 40 329 adults included in the Health Survey for England between 1995 and 2001, whereas no significant associations with FEV1/FVC were observed. In 1997, the Swiss Study on Air Pollution and Lung Disease in Adults (SAPALDIA), including 9651 adults, showed negative associations of ambient air pollutants NO2 and PM10 with both FEV1 and FVC [4]. The effect estimates for FVC were stronger than for FEV1 for various pollutants, and this was consistently the case in most subgroups (according to smoking status and respiratory symptoms). Reduced FVC, with FEV1 being normal or reduced to a lesser degree than FVC, suggests restrictive rather than obstructive lung disease (in which FEV1 specifically is reduced, resulting in a low FEV1/FVC ratio). Thus, findings from several European studies suggest that restrictive rather than obstructive ventilatory patterns associate with long-term low levels of exposure to ambient air pollution. A study with slightly different findings is the German Study on the influence of Air Pollution on Lung Function, Inflammation and Ageing (SALIA), including 2593 women. This study also found negative associations of NO2 and PM10 exposure with both FEV1 and FVC, yet the effects estimates for FEV1 were stronger than for FVC, and consequently there were small significant negative associations with the FEV1/FVC ratio [5]. A review article concluded that despite biological plausible mechanisms, there is suggestive, but not conclusive evidence that chronic exposure to air pollution is associated with the prevalence and incidence of chronic obstructive pulmonary disease (COPD), a disease characterised by airway obstruction [6]. Thus far, no studies have focused explicitly on whether air pollution exposure is associated with obstructive or restrictive ventilatory patterns. Exposure to ambient air pollution is associated with restrictive ventilatory patterns http://ow.ly/QWbD30236J1

Noise and somatic symptoms: A role for personality traits?

OBJECTIVES We investigated the role of a stress-sensitive personality on relations between noise, noise annoyance and somatic symptom reporting. First, we investigated the cross-sectional association of road traffic noise exposure and somatic symptoms, and its modification by hostility and vulnerability to stress. Second, we investigated the cross-sectional association of noise annoyance from eight sources (e.g. road traffic, aircraft, neighbours) and somatic symptoms, and its confounding by hostility and vulnerability to stress. METHODS Data were obtained from LifeLines, a general population cohort from the Netherlands. Road traffic noise was estimated using the Common Noise Assessment Methods in Europe (CNOSSOS-EU) noise model. Noise annoyance, hostility, vulnerability to stress, and somatic symptoms were assessed with validated questionnaires. RESULTS Poisson regression models adjusted for demographic and socioeconomic variables indicated no association of noise exposure and somatic symptoms (incidence rate ratio (IRR) 1.001; 95% confidence interval (CI) 1.000-1.001; n=56,937). Interactions of noise exposure and hostility and vulnerability to stress were not statistically significant. Small positive associations were found for noise annoyance from each of the eight sources and somatic symptoms, when adjusted for demographic and socioeconomic variables (e.g. for road traffic noise annoyance IRR 1.014, 95% CI 1.011-1.018; n=6177). Additional adjustment for hostility and vulnerability to stress resulted in small decreases of the IRRs for noise annoyance from each of the eight sources, but the associations remained statistically significant. CONCLUSIONS Personality facets hostility and vulnerability to stress did not modify the relation between road traffic noise exposure and somatic symptom reporting, or confound relations between noise annoyance and symptoms.