Heritability of cough across two generations: the RHINESSA study.

Aim: Heritability of cough has not yet been studied. We aimed to evaluate if individuals with cough are more likely to have offspring who develop cough, and if these associations differ by type of cough (productive/nonproductive). Methods: The RHINESSA Generation Study (Respiratory Health In Northern Europe, Spain and Australia) includes 7155 parents (initially aged 30-54) answering detailed questionnaires in 2000 and 2010, and 8176 offspring ≥20 years answering similar questionnaires in 2012-2019. Chronic cough was categorised as productive or nonproductive (dry) cough. Associations between parental and offspring cough were analysed using mixed-effects logistic regression, adjusting for offspring age, sex, body mass index, smoking history, education level, current asthma, rhinitis, nocturnal gastroesophageal reflux; parent sex and smoking history; centre and family. Results: Among parents with nonproductive cough, 11% of their offspring reported nonproductive cough, compared with 7% of offspring to parents without nonproductive cough, adjusted odds ratio (aOR) 1.59 (95% confidence interval 1.20-2.10). Among parents with productive cough, 14% of their offspring reported productive cough, compared with 11% of offspring to parents without productive cough, aOR 1.34 (1.07-1.67). No associations were found between parent productive cough-offspring nonproductive cough, nor between parent nonproductive cough-offspring productive cough. Conclusions: Parents with chronic cough are more likely to have offspring with chronic cough independent of parental asthma, suggesting cough to be a separate heritable trait. The type of cough is important, as the nonproductive cough in parent associates only with nonproductive cough in offspring, and the same applied for productive cough.

Association between physical activity over a 10-year period and current insomnia symptoms, sleep duration and daytime sleepiness: a European population-based study.

OBJECTIVES: To explore the relationship between physical activity over a 10-year period and current symptoms of insomnia, daytime sleepiness and estimated sleep duration in adults aged 39-67. DESIGN: Population-based, multicentre cohort study. SETTING: 21 centres in nine European countries. METHODS: Included were 4339 participants in the third follow-up to the European Community Respiratory Health Survey (ECRHS III), who answered questions on physical activity at baseline (ECRHS II) and questions on physical activity, insomnia symptoms, sleep duration and daytime sleepiness at 10-year follow-up (ECRHS III). Participants who reported that they exercised with a frequency of at least two or more times a week, for 1 hour/week or more, were classified as being physically active. Changes in activity status were categorised into four groups: persistently non-active; became inactive; became active; and persistently active. MAIN OUTCOME MEASURES: Insomnia, sleep time and daytime sleepiness in relation to physical activity. RESULTS: Altogether, 37% of participants were persistently non-active, 25% were persistently active, 20% became inactive and 18% became active from baseline to follow-up. Participants who were persistently active were less likely to report difficulties initiating sleep (OR 0.60, 95% CI 0.45-0.78), a short sleep duration of ≤6 hours/night (OR 0.71, 95% CI 0.59-0.85) and a long sleep of ≥9 hours/night (OR 0.53, 95% CI 0.33-0.84) than persistently non-active subjects after adjusting for age, sex, body mass index, smoking history and study centre. Daytime sleepiness and difficulties maintaining sleep were not related to physical activity status. CONCLUSION: Physically active people have a lower risk of some insomnia symptoms and extreme sleep durations, both long and short.

Respiratory symptoms, exacerbations and sleep disturbances are more common among participants with asthma and chronic airflow limitation: an epidemiological study in Estonia, Iceland and Sweden.

BACKGROUND: Chronic airflow limitation (CAL) is a hallmark of chronic obstructive pulmonary disease but is also present in some patients with asthma. We investigated respiratory symptoms, sleep and health status of participants with and without CAL with particular emphasis on concurrent asthma using data from adult populations in Iceland, Estonia and Sweden investigated within the Burden of Obstructive Lung Disease study. METHODS: All participants underwent spirometry with measurements of forced expiratory volume in 1 s (FEV1) and forced vital capacity (FVC) before and after bronchodilation. CAL was defined as postbronchodilator FEV1/FVC below the lower limit of normal. IgE-sensitisation and serum concentrations of eosinophil-derived neurotoxin (S-EDN) were assessed in a subsample. The participants were divided into four groups: no self-reported doctor's diagnosed asthma or CAL, asthma without CAL, CAL without asthma and asthma and CAL: χ2 test and analysis of variance were used in bivariable analyses and logistic and linear regression when analysing the independent association between respiratory symptoms, exacerbations, sleep-related symptoms and health status towards CAL, adjusting for centre, age, sex, body mass index, smoking history and educational level. RESULTS: Among the 1918 participants, 190 (9.9%) had asthma without CAL, 127 (6.6%) had CAL without asthma and 50 (2.6%) had CAL with asthma. Having asthma with CAL was associated with symptoms such as wheeze (adjusted OR (aOR) 6.53 (95% CI 3.53 to 12.1), exacerbations (aOR 12.8 (95% CI 6.97 to 23.6), difficulties initiating sleep (aOR 2.82 (95% CI 1.45 to 5.48), nocturnal gastro-oesophageal reflux (aOR 3.98 (95% CI 1.79 to 8.82)) as well as lower physical health status. In these analyses, those with no asthma and no CAL were the reference group. The prevalence of IgE-sensitisation was highest in both asthma groups, which also had higher levels of S-EDN. CONCLUSION: Individuals with self-reported asthma with CAL suffer from a higher burden of respiratory and sleep-related symptoms, higher exacerbation rates and lower health status when compared with participants with asthma alone or CAL alone.

Gas cooking indoors and respiratory symptoms in the ECRHS cohort.

BACKGROUND: Gas cooking is an important source of indoor air pollutants, and there is some limited evidence that it might adversely be associated with respiratory health. Using repeated cross-sectional data from the multi-centre international European Community Respiratory Health Survey, we assessed whether adults using gas cookers have increased risk of respiratory symptoms compared to those using electric cookers and tested whether there was effect modification by a priori selected factors. METHODS: Data on respiratory symptoms and gas cooking were collected from participants at 26-55 and 38-67 years (median time between examinations 11.4 years) from interviewer-led questionnaires. Repeated associations between gas cooking (versus electric) and respiratory symptoms were estimated using multivariable mixed-effects logistic regression models adjusted for age, sex, study arm, smoking status, education level, and included random intercepts for participants within study centres. Analyses were repeated using a 3-level variable for type of cooker and gas source. Effect modification by ventilation habits, cooking duration, sex, age atopy, asthma, and study arm were examined. RESULTS: The sample included 4337 adults (43.7% males) from 19 centres in 9 countries. Gas cooking increased the risk of "shortness of breath whilst at rest" (OR = 1.38; 95%CI: 1.06-1.79) and "wheeze with breathlessness" (1.32; 1.00-1.74). For several other symptoms, effect estimates were larger in those who used both gas hobs and ovens, had a bottled gas source and cooked for over 60 min per day. Stratifying results by sex and age found stronger associations in females and younger adults. CONCLUSION: This multi-centre international study, using repeat data, suggested using gas cookers in the home was more strongly associated than electric cookers with certain respiratory symptoms in adults. As gas cooking is common, these results may play an important role in population respiratory health.

Spirometric patterns in young and middle-aged adults: a 20-year European study.

BACKGROUND: Understanding the natural history of abnormal spirometric patterns at different stages of life is critical to identify and optimise preventive strategies. We aimed to describe characteristics and risk factors of restrictive and obstructive spirometric patterns occurring before 40 years (young onset) and between 40 and 61 years (mid-adult onset). METHODS: We used data from the population-based cohort of the European Community Respiratory Health Survey (ECRHS). Prebronchodilator forced expiratory volume in one second (FEV1) and forced vital capacity (FVC) were assessed longitudinally at baseline (ECRHS1, 1993-1994) and again 20 years later (ECRHS3, 2010-2013). Spirometry patterns were defined as: restrictive if FEV1/FVC≥LLN and FVC<10th percentile, obstructive if FEV1/FVC

Gastroesophageal reflux and snoring are related to asthma and respiratory symptoms: Results from a Nordic longitudinal population survey.

AIM: To study if individuals with nocturnal gastroesophageal reflux (nGER) and habitual snoring are more likely to develop asthma and respiratory symptoms (i.e. wheeze, cough, chest tightness, breathlessness) than those without these conditions, and if these associations are additive. METHODS: We used data from the population-based prospective questionnaire study Respiratory Health in Northern Europe (RHINE) (11,024 participants), with data from 1999 and 2011. Participants with heartburn or belching after going to bed, at least 1 night/week, were considered to have nGER. Participants reporting loud snoring at least 3 nights/week were considered to have habitual snoring. Participants were grouped into four groups by their nGER and snoring status: "never"; "former"; "incident"; "persistent". Incident respiratory symptoms were analyzed among participants without respective symptom at baseline. RESULTS: Snoring and nGER were independently associated with incident asthma and respiratory symptoms. The risk of incident wheeze was increased in subjects with incident or persistent snoring (adjusted odds ratio (95 % CI): 1.44 (1.21-1.72)), nGER (2.18 (1.60-2.98)) and in those with both snoring and nGER (2.59 (1.83-3.65)). The risk of developing asthma was increased in subjects with incident or persistent snoring (1.44 (1.15-1.82)), nGER (1.99 (1.35-2.93)) and in those with both snoring and nGER (1.72 (1.06-2.77)). No significant interaction was found between snoring and nGER. A similar pattern was found for the incidence of all other respiratory symptoms studied, with the highest risk among those with both incident or persistent nGER and snoring. CONCLUSION: The risk of developing asthma and respiratory symptoms is increased among subjects with nGER and habitual snoring. These associations are independent of each other and confounding factors. Snoring and nGER together are additive on respiratory symptoms.

Early life exposures contributing to accelerated lung function decline in adulthood - a follow-up study of 11,000 adults from the general population.

Background: We aimed to assess whether exposure to risk factors in early life from conception to puberty continue to contribute to lung function decline later in life by using a pooled cohort comprising approx. 11,000 adults followed for more than 20 years and with up to three lung function measurements. Methods: Participants (20-68 years) in the ECRHS and NFBC1966 cohort studies followed in the periods 1991-2013 and 1997-2013, respectively, were included. Mean annual decline in maximum forced expired volume in 1 s (FEV1) and forced vital capacity (FVC) were main outcomes. Associations between early life risk factors and change in lung function were estimated using mixed effects linear models adjusted for sex, age, FEV1, FVC and height at baseline, accounting for personal smoking. Findings: Decline in lung function was accelerated in participants with mothers that smoked during pregnancy (FEV1 2.3 ml/year; 95% CI: 0.7, 3.8) (FVC 2.2 ml/year; 0.2, 4.2), with asthmatic mothers (FEV1 2.6 ml/year; 0.9, 4.4) (FEV1/FVC 0.04 per year; 0.04, 0.7) and asthmatic fathers (FVC 2.7 ml/year; 0.5, 5.0), and in women with early menarche (FVC 2.4 ml/year; 0.4, 4.4). Personal smoking of 10 pack-years contributed to a decline of 2.1 ml/year for FEV1 (1.8, 2.4) and 1.7 ml/year for FVC (1.3, 2.1). Severe respiratory infections in early childhood were associated with accelerated decline among ever-smokers. No effect-modification by personal smoking, asthma symptoms, sex or cohort was found. Interpretation: Mothers' smoking during pregnancy, parental asthma and early menarche may contribute to a decline of FEV1 and FVC later in life comparable to smoking 10 pack-years. Funding: European Union's Horizon 2020; Research Council of Norway; Academy of Finland; University Hospital Oulu; European Regional Development Fund; Spanish Ministry of Science and Innovation; Generalitat de Catalunya.

Indoor Airborne Microbiome and Endotoxin: Meteorological Events and Occupant Characteristics Are Important Determinants.

Airborne bacteria and endotoxin may affect asthma and allergies. However, there is limited understanding of the environmental determinants that influence them. This study investigated the airborne microbiomes in the homes of 1038 participants from five cities in Northern Europe: Aarhus, Bergen, Reykjavik, Tartu, and Uppsala. Airborne dust particles were sampled with electrostatic dust fall collectors (EDCs) from the participants' bedrooms. The dust washed from the EDCs' clothes was used to extract DNA and endotoxin. The DNA extracts were used for quantitative polymerase chain (qPCR) measurement and 16S rRNA gene sequencing, while endotoxin was measured using the kinetic chromogenic limulus amoebocyte lysate (LAL) assay. The results showed that households in Tartu and Aarhus had a higher bacterial load and diversity than those in Bergen and Reykjavik, possibly due to elevated concentrations of outdoor bacterial taxa associated with low precipitation and high wind speeds. Bergen-Tartu had the highest difference (ANOSIM R = 0.203) in ß diversity. Multivariate regression models showed that α diversity indices and bacterial and endotoxin loads were positively associated with the occupants' age, number of occupants, cleaning frequency, presence of dogs, and age of the house. Further studies are needed to understand how meteorological factors influence the indoor bacterial community in light of climate change.

Maternal and paternal tuberculosis is associated with increased asthma and respiratory symptoms in their offspring: a study from Northern Europe.

Background: Given the profound impact of tuberculosis (TB) on immunity and given murine studies suggesting that infections may influence immunity across generations, we hypothesize that parental TB might impact health and disease in future offspring. Objective: This study investigated the impact of maternal and paternal TB on offspring asthma and respiratory symptoms. Methods: We included data from the third follow-up of the Respiratory Health in Northern Europe study (RHINE). Information on own asthma status, asthma-like symptoms and other respiratory symptoms, as well as information about parental TB and asthma, were collected using standardized questionnaires. The associations between parental TB and RHINE participants' asthma and respiratory symptoms were analyzed using multiple logistic regression, with adjustment for parental education, smoking habits and asthma. Results: Of 8,323 study participants, 227 (2.7%) reported only paternal TB, 282 (3.4%) only maternal TB, and 33 (0.4%) reported that both parents had TB. We found a higher risk of asthma (aOR: 1.29, 95% CI: 1.05-1.57) in offspring with a history of parental TB as compared to offspring without parental TB., Parental TB was significantly associated with allergic asthma in offspring (aOR: 1.58, 95% CI: 1.29-2.05), while no significant association between parental TB and asthma without allergy (aOR: 1.00, 95% CI: 0.76-1.32) in offspring was observed. Conclusion: Results from this study indicate that parental TB might be a risk factor for offspring's asthma and respiratory symptoms. We raise the hypothesis that the immunological impact of infections might be transmitted to influence offspring phenotype in humans.