Residential greenness-related DNA methylation changes.

BACKGROUND: Residential greenness has been associated with health benefits, but its biological mechanism is largely unknown. Investigation of greenness-related DNA methylation profiles can contribute to mechanistic understanding of the health benefits of residential greenness. OBJECTIVE: To identify DNA methylation profiles associated with greenness in the immediate surroundings of the residence. METHODS: We analyzed genome-wide DNA methylation in 1938 blood samples (982 participants) from the Swiss Cohort Study on Air Pollution and Lung and Heart Diseases in Adults (SAPALDIA). We estimated residential greenness based on normalized difference vegetation index at 30 × 30 m cell (green30) and 500 m buffer (green500) around the residential address. We conducted epigenome-wide association study (EWAS) to identify differentially methylated CpGs and regions, and enrichment tests by comparing to the CpGs that previous EWAS identified as associated with allergy, physical activity, and allostatic load-relevant biomarkers. RESULTS: We identified no genome-wide significant CpGs, but 163 and 56 differentially methylated regions for green30 and green500, respectively. Green30-related DNA methylation profiles showed enrichments in allergy, physical activity, and allostatic load, while green500-related methylation was enriched in allergy and allostatic load. CONCLUSIONS: Residential greenness may have health impacts through allergic sensitization, stress coping, or behavioral changes. Exposure to more proximal greenness may be more health-relevant.

Factors associated with cessation of smoking among Swiss adults between 1991 and 2011: results from the SAPALDIA cohort.

INTRODUCTION: Smoking is still the most preventable cause of disease and premature death in Switzerland, as elsewhere. We aimed to assess the main determinants of smoking cessation in the population-based cohort of SAPALDIA (Swiss Cohort Study on Air Pollution and Lung and Heart Diseases in Adults). METHODS: The SAPALDIA study was initiated in 1991 with 9651 participants aged 18 to 60 years from eight areas (S1). Follow-up assessments were conducted in 2002 (S2; 8047 participants) and 2010/11 (S3; 6088 participants). At each survey, detailed information on health and potential health-related factors was collected and lung function measured. Using logistic regression, we assessed predictors of smoking cessation between S1 and S2 and between S2 and S3. RESULTS: In both periods, highest educational level (summary odds ratio [OR] 1.49, 95% confidence interval [CI] 1.08-2.06; ref. lowest level), FEV1/FVC <0.5 (OR 6.19, 95% CI 2.44-15.7, ref. FEV1/FVC ≥0.7), higher age in men (OR 1.02, 95% CI 1.01-1.03, per year) and overweight (OR 1.38, 95% CI 1.16-1.64) were significant predictors of smoking cessation. Nicotine dependence (OR 0.97, 95% CI 0.96-0.98, per cigarette smoked a day) and female sex between age 45 and 60 (e.g., OR 0.74, 95% CI 0.61-0.91, at age 50) were negatively associated with smoking cessation. Moreover, smokers at S2 reporting a diagnosis of depression were less likely to quit smoking by S3 (OR 0.53, 95% CI 0.30-0.93). CONCLUSIONS: Prospective tobacco control policies in Switzerland should be addressed to women, younger persons and persons of lower education.

Hypertension, diabetes and lifestyle in the long-term - Results from a Swiss population-based cohort.

Healthy lifestyles are integral in preventing and treating common cardiovascular and metabolic diseases. The aim of this study was to observe smoking habits, alcohol intake, physical activity and body mass index over a 10-year period in a population-based cohort, particularly focusing on participants with hypertension and type 2 diabetes mellitus. Included were 4155 participants from the first (2001-2003) and second (2010-2011) follow-ups of the Swiss Cohort Study on Air Pollution and Lung and Heart Disease in Adults (SAPALDIA). Information was collected via health questionnaire; height and weight were measured. In a healthy lifestyle score one point was attributed per criterion; non-smoking, low risk alcohol consumption, BMI<25kg/m2, and regular physical activity. Overall in 2010-2011, 16.4% were smokers, 7.7% had at risk alcohol consumption, 25.5% were physically inactive and 57.8% were overweight or obese. Both those with hypertension and diabetes had lower mean healthy lifestyle scores than those without disease. Women with incident hypertension from 2001 to 2011 had lower odds of improving their healthy lifestyle score during this time period compared to those without this disease. In contrast, women with incident diabetes had higher odds of lifestyle score improvement. In men, neither hypertension nor diabetes was associated with change in lifestyle score. Our findings suggest that, irrespective of disease status, preventative attention is needed, particularly in regards to physical activity and bodyweight. These needs could be met by population-based interventions, a necessary and suitable option in both preventing and treating the non-communicable disease epidemic which currently faces countries worldwide.

High blood pressure: prevalence and adherence to guidelines in a population-based cohort.

QUESTIONS UNDER STUDY: High blood pressure, the single leading health risk factor worldwide, contributes greatly to morbidity and mortality. This study aimed to add to the understanding of diagnosed and undiagnosed high blood pressure in Switzerland and to evaluate adherence to hypertension guidelines. METHODS: Included were 3962 participants from the first (2001-2003) and second (2010-2011) follow-ups of the population-based Swiss Cohort Study on Air Pollution and Lung and Heart Disease in Adults. High blood pressure was defined as blood pressure ≥140/90 mm Hg and the prevalence of doctor-diagnosed hypertension was based on questionnaire information. RESULTS: High blood pressure was found in 34.9% of subjects, 49.1% of whom were unaware of this condition; 30.0% had doctor-diagnosed hypertension and, although 82.1% of these received drug treatments, in only 40.8% was blood pressure controlled (<140/90 mm Hg). Substantial first-line beta-blocker use and nonadherence to comorbidity-specific prescription guidelines were observed and remained mostly unexplained. Age-adjusted rates of unawareness and uncontrolled hypertension were more than 20% higher than in the USA. CONCLUSIONS: There is room for improvement in managing hypertension in Switzerland. Population-based observational studies are essential for identifying and evaluating unmet needs in healthcare; however, to pinpoint the underlying causes it is imperative to facilitate linkage of cohort data to medical records.

Particulate Matter and Subclinical Atherosclerosis: Associations between Different Particle Sizes and Sources with Carotid Intima-Media Thickness in the SAPALDIA Study.

BACKGROUND: Subclinical atherosclerosis has been associated with long-term exposure to particulate matter (PM), but the relevance of particle size and sources of exposure remains unclear. OBJECTIVES: We investigated the association of long-term exposure to PM10 (≤ 10 µm), PM2.5 (≤ 2.5 µm: total mass, vehicular, and crustal sources), and ultrafine particles [UFP < 0.1 µm: particle number concentration (PNC) and lung-deposited surface area (LDSA)] with carotid intima-media thickness (CIMT). METHODS: We used data from 1,503 participants ≥ 50 years old who participated in the third examination of the Swiss SAPALDIA cohort. Exposures were obtained from dispersion models and land-use regression models. Covariate information, including previous cardiovascular risk factors, was obtained from the second and third SAPALDIA examinations. RESULTS: The adjusted percent difference in CIMT associated with an exposure contrast between the 10th and 90th percentile was 1.58% (95% CI: -0.30, 3.47%) for PM10, 2.10% (95% CI: 0.04, 4.16%) for PM2.5, 1.67% (95% CI: -0.13, 3.48%) for the vehicular source of PM2.5, -0.58% (95% CI: -3.95, 2.79%) for the crustal source of PM2.5, 2.06% (95% CI: 0.03, 4.10%) for PNC, and 2.32% (95% CI: 0.23, 4.40%) for LDSA. Stronger associations were observed among diabetics, subjects with low-educational level, and those at higher cardiovascular risk. CONCLUSIONS: CIMT was associated with exposure to PM10, PM2.5, and UFP. The PM2.5 source-specific analysis showed a positive association for the vehicular source but not for the crustal source. Although the effects of PNC and LDSA were similar in magnitude, two-pollutant and residual-based models suggested that LDSA may be a better marker for the health relevance of UFP. Citation: Aguilera I, Dratva J, Caviezel S, Burdet L, de Groot E, Ducret-Stich RE, Eeftens M, Keidel D, Meier R, Perez L, Rothe T, Schaffner E, Schmit-Trucksäss A, Tsai MY, Schindler C, Künzli N, Probst-Hensch N. 2016. Particulate matter and subclinical atherosclerosis: associations between different particle sizes and sources with carotid intima-media thickness in the SAPALDIA study. Environ Health Perspect 124:1700-1706; http://dx.doi.org/10.1289/EHP161.

Rhinitis in Swiss adults is associated with asthma and early life factors, but not second hand tobacco smoke or obesity.

BACKGROUND: Second hand tobacco smoke (SHS) and overweight/obesity are risk factors for asthma and lower airway respiratory symptoms. We investigated whether SHS or overweight/obesity were also associated with allergic or non-allergic rhinitis. METHODS: Cross-sectional data were obtained during the second SAPALDIA Study. Interviewer administered questionnaires were completed by 8047 participants from 8 communities in Switzerland. Blood was collected from 5841 participants and tested for allergen specific IgE. Allergic rhinitis was defined as nasal symptoms with detectable IgE. Data were analysed by multinomial logistic regression with four outcome categories defined according to the presence or absence of rhinitis and/or atopy. RESULTS: The prevalence of allergic rhinitis was 885 (15.2%) and non-allergic rhinitis 323 (5.5%). The risk of allergic rhinitis was increased in subjects with physician diagnosed asthma (Relative Risk Ratio 6.81; 95%CI 5.39, 8.6), maternal atopy (1.56; 1.27, 1.92) and paternal atopy (1.41; 1.11, 1.79). Older subjects were at lower risk (0.96; 0.95,0.97 per year), as were those raised on a farm (0.64; 0.49,0.84), with older siblings (0.92; 0.86,0.97 per sib) or from rural areas. The risk of non-allergic rhinitis was also increased in subjects with physician diagnosed asthma (4.02; 2.86, 5.67), reduced in males (0.59; 0.46, 0.77), but not associated with upbringing on a farm or older siblings. There were no significant associations of SHS or overweight/obesity with either form of rhinitis. CONCLUSIONS: Allergic and non-allergic rhinitis have different risk factors apart from asthma. There are significant regional variations within Switzerland, which are not explained by the factors examined.

Early Life Origins of Lung Ageing: Early Life Exposures and Lung Function Decline in Adulthood in Two European Cohorts Aged 28-73 Years.

OBJECTIVES: Early life environment is essential for lung growth and maximally attained lung function. Whether early life exposures impact on lung function decline in adulthood, an indicator of lung ageing, has scarcely been studied. METHODS: Spirometry data from two time points (follow-up time 9-11 years) and information on early life exposures, health and life-style were available from 12862 persons aged 28-73 years participating in the European population-based cohorts SAPALDIA (n = 5705) and ECRHS (n = 7157). The associations of early life exposures with lung function (FEV1) decline were analysed using mixed-effects linear regression. RESULTS: Early life exposures were significantly associated with FEV1 decline, with estimates almost as large as personal smoking. FEV1 declined more rapidly among subjects born during the winter season (adjusted difference in FEV1/year of follow-up [95%CI] -2.04ml [-3.29;-0.80]), of older mothers, (-1.82 ml [-3.14;-0.49]) of smoking mothers (-1.82ml [-3.30;-0.34] or with younger siblings (-2.61ml [-3.85;-1.38]). Less rapid FEV1-decline was found in subjects who had attended daycare (3.98ml [2.78;5.18]), and indicated in subjects with pets in childhood (0.97ml [-0.16;2.09]). High maternal age and maternal smoking appeared to potentiate effects of personal smoking. The effects were independent of asthma at any age. CONCLUSION: Early life factors predicted lung function decline decades later, suggesting that some mechanisms related lung ageing may be established early in life. Early life programming of susceptibility to adult insults could be a possible pathway that should be explored further.

Gender differences in adult-onset asthma: results from the Swiss SAPALDIA cohort study.

A higher incidence of asthma is reported in women compared with men, but evidence in later adulthood is limited. We aimed to determine the 20-year cumulative incidence of adult asthma in Switzerland and its relation to sex, taking into account age and allergic sensitisation.We assessed incidence of self-report of doctor-diagnosed asthma between 1991/1992 and 2010/2011 in 5128 subjects without asthma, aged 18-60 years at baseline. The age-related probability of asthma onset was analysed by logistic regression adjusting for potential confounders and stratified by sex and allergic sensitisation at baseline.Over 20 years, 128 (5.1%) men and 198 (7.5%) women newly reported doctor-diagnosed asthma. The adjusted odds ratio for female sex was 1.99 (95% CI 1.54-2.57) overall, 3.21 (95% CI 2.12-4.85) among nonsensitised subjects, and 1.43 (95% CI 1.02-2.02) in sensitised subjects. The probability of asthma onset decreased with increasing baseline age in women but not in men. The higher probability of new asthma in sensitised compared with nonsensitised men was unrelated to age, whereas in women it decreased with age.Asthma incidence was higher in women than in men but decreased with increasing age. The female predominance was considerably stronger in nonsensitised adults compared with those with allergic sensitisation.

Spirometer Replacement and Serial Lung Function Measurements in Population Studies: Results From the SAPALDIA Study.

The Swiss Cohort Study on Air Pollution and Lung and Heart Disease in Adults (SAPALDIA), a population cohort study, used heated-wire spirometers in 1991 and 2002 and then ultrasonic spirometers in 2010 revealing measurement bias in healthy never smokers. To provide a practical method to control for measurement bias given the replacement of spirometer in long-term population studies, we built spirometer-specific reference equations from healthy never smokers participating in 1991, 2002, and 2010 to derive individualized corrections terms. We compared yearly lung function decline without corrections terms with fixed terms that were obtained from a quasi-experimental study and individualized terms. Compared with baseline reference equations, spirometer-specific reference equations predicted lower lung function. The mean measurement bias increased with age and height. The decline in forced expiratory volume in 1 second during the reference period of 1991-2002 was 31.5 (standard deviation (SD), 28.7) mL/year while, after spirometer replacement, uncorrected, corrected by fixed term, and individualized term, the declines were 47.0 (SD, 30.1), 40.4 (SD, 30.1), and 30.4 (SD, 29.9) mL/year, respectively. In healthy never smokers, ultrasonic spirometers record lower lung function values than heated-wire spirometers. This measurement bias is sizeable enough to be relevant for researchers and clinicians. Future reference equations should account for not only anthropometric variables but also spirometer type. We provide a novel method to address spirometer replacement in cohort studies.

Sex-specific associations of cardiovascular risk factors with carotid stiffness--results from the SAPALDIA cohort study.

OBJECTIVE: Manifestation of cardiovascular disease (CVD) occurs with clear sex differences. Carotid stiffness (CS) parameters are increasingly used for CVD risk assessment but the sex-specific association with CVD risk factors as well as association patterns between CS parameters are largely unknown, which we investigated in SAPALDIA population-based cohort participants. METHODS: Risk factors of 2545 participants without clinically manifest disease were evaluated in 2001-2003 and different CS parameters were assessed in carotid ultrasound scans in 2010-2011. Stratified and non-stratified mixed linear models and multivariate regression analyses were used to examine sex-specific associations, differences and association patterns of single risk factors and CS parameters. RESULTS: HDL cholesterol was the only significant protective determinant of reduced CS for both sexes (ranges of CS parameters: -3.7; -0.8% of changes in geometric mean per 1SD of the risk factor on an inverted scale) and significant adverse risk factors were BMI (-0.5; 4.7%), systolic (-1.23; 4.7%) and diastolic blood pressure (1.4; 4.4%), heart rate (2.7; 7.9%), C-reactive protein (0.6; 3.3%) and smoking (-2.82; 1%), all p-values of multivariate analyses were <0.01. Sex differences with stiffer CS parameters in men were observed for increased heart rate (p = 0.001) and LDL cholesterol (p < 0.001) and in women for triglyceride (p < 0.003). Similar association patterns were found for most CS parameters. CONCLUSION: Sex-specific associations of cardiovascular risk factors may reflect a sex-specific burden of atherosclerotic risk factors and similar association patterns across different CS parameters within men and women may allow the use of CS parameters in an exchangeable manner.

Variability and reproducibility of carotid structural and functional parameters assessed with transcutaneous ultrasound - results from the SAPALDIA Cohort Study.

OBJECTIVE: Carotid intima media thickness (CIMT) and local stiffness are vascular biomarkers of atherosclerotic burden. We investigated the variability and reproducibility of clinically relevant structural (CIMT, lumen diameter) and functional parameters (strain, distensibility, compliance, ß-stiffness index, Peterson's elastic modulus and Young's elastic modulus) measured in B-mode ultrasound sequences of the common carotid artery in the second follow up of the Swiss Cohort Study on Air Pollution and Lung and Heart Diseases In Adults (SAPALDIA3). METHODS: Ultrasound sequential images were examined twice over a 1 cm segment across at least one heart cycle in 165 SAPALDIA3 participants. To assess variability and reproducibility of structural and functional parameters, individual coefficients of variation (CV), intraclass correlation (ICC), Bland-Altman plots and mixed effect regressions were used. RESULTS: ICCs of repeated examinations ranged between 0.67 and 0.77 for blood pressure indices, between 0.87 and 0.97 for structural properties and between 0.75 and 0.79 for functional parameters. CV was lowest in structural parameters (1.6-4.6%), followed by blood pressure (5.1-7.9%) and functional indices (11.0-13.1%). Variations in all parameters were predominantly explained by subjects (>74% in functional, >82% in structural properties). Bland-Altman plots for functional indices showed mean and standard deviation of the respective mean value of 4.2(19.6)% for strain, 1.9(24.4)% for distensibility, 2.4(22.2)% for compliance, 3.0(24.4)% for ß-stiffness index, 0.9(25.7)% for Peterson's elastic modulus and 1.2(27.9)% for Young's elastic modulus. CONCLUSION: The results show that SAPALDIA3 measurements of transcutaneous ultrasound examinations have an excellent reproducibility of structural parameters and a good reproducibility of functional indices.

Improvements in PM10 exposure and reduced rates of respiratory symptoms in a cohort of Swiss adults (SAPALDIA).

RATIONALE: Reductions in mortality following improvements in air quality were documented by several studies, and our group found, in an earlier analysis, that decreasing particulate levels attenuate lung function decline in adults. OBJECTIVES: We investigated whether decreases in particulates with an aerodynamic diameter of less than 10 microm (PM10) were associated with lower rates of reporting respiratory symptoms (i.e., decreased morbidity) on follow-up. METHODS: The present analysis includes 7,019 subjects who underwent detailed baseline examinations in 1991 and a follow-up interview in 2002. Each subject was assigned model-based estimates of average PM10 during the 12 months preceding each health assessment and the difference was used as the exposure variable of interest (DeltaPM10). Analyses were stratified by symptom status at baseline and associations between DeltaPM10 and change in symptom status during follow-up were adjusted for important baseline characteristics, smoking status at follow-up, and season. We then estimated adjusted odds ratios for symptoms at follow-up and numbers of symptomatic cases prevented due to the observed reductions in PM10. MEASUREMENTS AND MAIN RESULTS: Residential exposure to PM10 was lower in 2002 than in 1991 (mean decline 6.2 microg/m3; SD = 3.9 microg/m3). Estimated benefits (per 10,000 persons) attributable to the observed changes in PM10-levels were: 259 (95% confidence interval [CI]: 102-416) fewer subjects with regular cough, 179 (95% CI, 30-328) fewer subjects with chronic cough or phlegm and 137 (95% CI, 9-266) fewer subjects with wheezing and breathlessness. CONCLUSIONS: Reductions in particle levels in Switzerland over the 11-year follow-up period had a beneficial effect on respiratory symptoms among adults.

Living near main streets and respiratory symptoms in adults: the Swiss Cohort Study on Air Pollution and Lung Diseases in Adults.

The Swiss Cohort Study on Air Pollution and Lung Diseases in Adults (SAPALDIA), conducted in 1991 (SAPALDIA 1) in eight areas among 9,651 randomly selected adults aged 18-60 years, reported associations among the prevalence of respiratory symptoms, nitrogen dioxide, and particles with an aerodynamic diameter of less than 10 microg/m3. Later, 8,047 subjects reenrolled in 2002 (SAPALDIA 2). The effects of individually assigned traffic exposures on reported respiratory symptoms were estimated, while controlling for socioeconomic and exposure- and health-related factors. The risk of attacks of breathlessness increased for all subjects by 13% (95% confidence interval: 3, 24) per 500-m increment in the length of main street segments within 200 m of the home and decreased in never smokers by 12% (95% confidence interval: 0, 22) per 100-m increment in distance from home to a main street. Living within 20 m of a main street increased the risks of regular phlegm by 15% (95% confidence interval: 0, 31) and wheezing with breathing problems by 34% (95% confidence interval: 0, 79) in never smokers. In 2002, the effects related to road distance were different from those in 1991, which could be due to changes in the traffic pollution mixture. These findings among a general population provide strong confirmation that living near busy streets leads to adverse respiratory health effects.

Respiratory effects of environmental tobacco exposure are enhanced by bronchial hyperreactivity.

RATIONALE: Exposure to environmental tobacco smoke (ETS) is associated with increased reports of respiratory symptoms and reduced lung function, but the long-term effects of ETS are unclear, notably in healthy individuals with bronchial hyperresponsiveness (BHR). OBJECTIVE: To assess the longitudinal effects of ETS exposure on the development of respiratory symptoms and spirometry in subjects with BHR. METHODS: The study population included 1,661 never-smokers from the SAPALDIA (Swiss Study on Air Pollution and Lung Diseases in Adults) cohort, assessed in 1991 (baseline) and 11 yr later, who were symptom-free at baseline. Incident reports of respiratory symptoms and results of spirometry were assessed at the follow-up survey. MAIN RESULTS: Exposure to ETS reported in the two surveys was strongly associated with the development of cough (odds ratio, 2.1; 95% confidence interval, 1.2-3.7; p = 0.01). In subjects with BHR exposed to ETS at both surveys, a trend for strong associations were observed for wheeze, cough, dyspnea, and chronic bronchitis; however, the association reached statistical significance only for the symptom of dyspnea (p < 0.01). Lower FEV1/FVC (mean +/- SD, 72.9 +/- 7.7 vs. 76.8 +/- 6.1%; p < 0.01) and FEF(25-75) (forced expiratory flow, midexpiratory phase)/FVC (mean +/- SD, 56.1 +/- 22.5 vs. 68.1 +/- 21.6%; p < 0.01) were observed in subjects with BHR exposed to ETS compared with nonexposed subjects without BHR. Lower values were found in subjects continuing exposure by the follow-up survey. CONCLUSION: Exposure to ETS was strongly associated with the development of respiratory symptoms in previously asymptomatic subjects with BHR within 11 yr. Furthermore, subjects with underlying BHR had reduced lung function at follow-up, thus suggesting a higher risk for the development of chronic respiratory disease in this subset of the population.

Accelerated decline in lung function in smoking women with airway obstruction: SAPALDIA 2 cohort study.

BACKGROUND: The aim was to determine if effects from smoking on lung function measured over 11 years differ between men and women. METHODS: In a prospective population based cohort study (Swiss Study on Air Pollution and Lung Diseases in Adults) current smokers in 1991 (18-60 yrs) were reassessed in 2002 (n = 1792). Multiple linear regression was used to estimate effects from pack-years of cigarettes smoked to 1991 and mean packs of cigarettes smoked per day between 1991 and 2002 on change in lung volume and flows over the 11 years. RESULTS: In both sexes, packs smoked between assessments were related to lung function decline but pack-years smoked before 1991 were not. Mean annual decline in FEV1 was -10.4 mL(95%CI -15.3, -5.5) per pack per day between assessments in men and -13.8 mL(95%CI-19.5,-8.1) in women. Decline per pack per day between 1991 and 2002 was lower in women who smoked in 1991 but quit before 2002 compared to persistent smokers (-6.4 vs -11.6 mL, p = 0.05) but this was not seen in men (-14.3 vs -8.8 mL p = 0.49). Smoking related decline was accelerated in men and women with airway obstruction, particularly in women where decline in FEV1 was three fold higher in participants with FEV1/FVC<0.70 compared to other women (-39.4 vs -12.2 mL/yr per pack per day, p < 0.002). CONCLUSION: There are differences in effects from smoking on lung function between men and women. Lung function recovers faster in women quitters than in men. Women current smokers with airway obstruction experience a greater smoking related decline in lung function than men.

Validity and reliability of a French version of the MRF-28 health-related quality of life questionnaire.

BACKGROUND: Evaluation of health-related quality of life (HRQL) in chronic respiratory failure (CRF) is an important issue for evaluating the impact of treatment. OBJECTIVES: To elaborate a French version of the Maugeri Foundation Respiratory Failure Questionnaire (MRF-28) disease-specific HRQL questionnaire and determine its validity and reliability in patients with CRF treated by home mechanical ventilation (HMV). METHODS: Forward- and back-translation of the MRF-28 questionnaire; the final version was submitted to 81 patients treated with HMV for CRF, simultaneously with the St. George's Respiratory Questionnaire (SGRQ), the Short Form 36 (SF-36), and the Hospital Anxiety and Depression scale (HAD). Validity was determined by correlation with previously validated HRQL scores and recorded physiological parameters. Reliability was evaluated by assessing internal consistency and test-retest stability of the MRF-28 scores. RESULTS: The French version of the MRF-28 and its subscores ('daily activity', 'cognitive function', and 'invalidity') were highly significantly correlated with subscores of the SGRQ, the SF-36 and the HAD. Both the MRF-28 and the SGRQ were correlated only with age and the 6-min walk test. The MRF-28 showed high test-retest reliability after 2 weeks (r2 = 0.80, p < 0.0001) and high internal consistency (Crohnbachs' alpha coefficient: 0.91). CONCLUSION: The French version of the MRF-28 is a valid and reliable disease-specific questionnaire for assessing HRQL in patients with CRF.

Helium-oxygen versus air-oxygen noninvasive pressure support in decompensated chronic obstructive disease: A prospective, multicenter study.

OBJECTIVE: To study whether noninvasive pressure support ventilation (NIPSV) with helium/oxygen (He/oxygen), which can reduce dyspnea, PaCO2, and work of breathing more than NIPSV with air/oxygen in decompensated chronic obstructive pulmonary disease, could have beneficial consequences on outcome and hospitalization costs. DESIGN: Prospective, randomized, multicenter study. SETTING: Intensive care units of three tertiary care university hospitals. PATIENTS: All patients with chronic obstructive pulmonary disease admitted to the intensive care units for NIPSV during a 24-month period. INTERVENTIONS: Patients were randomized to NIPSV with air/oxygen or He/oxygen. NIPSV settings, number of daily trials, decision to intubate, and intensive care unit and hospital discharge criteria followed standard practice guidelines. RESULTS: A total of 123 patients (male/female ratio, 71:52; age, 71 +/- 10 yrs, Acute Physiology and Chronic Health Evaluation II, 17 +/- 4) were included. Intubation rate (air/oxygen 20% vs. He/oxygen 13%) and length of stay in the intensive care unit (air/oxygen 6.2 +/- 5.6 vs. He/oxygen 5.1 +/- 4 days) were comparable. The post-intensive care unit hospital stay was lower with He/oxygen (air/oxygen 19 +/- 12 vs. He/oxygen 13 +/- 6 days, p < .002). Cost of NIPSV gases was higher with He/oxygen, but total hospitalization costs were lower by $3,348 per patient with He/oxygen. No complications were associated with the use of He/oxygen. CONCLUSION: He/oxygen did not significantly reduce intubation rate or intensive care unit stay, but hospital stay was shorter and total costs were lower. He/oxygen NIPSV can be safely administered and could prove to be a cost-effective strategy.