Trude Duelien Skorge

Mortality by Level of Emphysema and Airway Wall Thickness

RATIONALE There is limited knowledge of the prognostic value of quantitative computed tomography (CT) measures of emphysema and airway wall thickness (AWT) on mortality. OBJECTIVES To examine 8-year mortality in relation to CT-measured emphysema and AWT, and assess if potential impact of these predictors remained after adjustment for lung function. METHODS In the Norwegian GenKOLS study of 2003-2005, 947 ever-smokers (49% with COPD) aged 40-85 years performed spirometry and CT examination. Mortality data from 2003-2011 were gathered from the Norwegian Cause of Death Registry. CT emphysema % low-attenuation areas (%LAA) and standardized measure for AWT (AWT-Pi10) were main predictors. We performed Laplace regression for survival data, estimating survival time for specified population percentiles within each emphysema category. Models were adjusted for sex, FEV1, COPD status, age, body mass index, smoking, and inflation level. MEASUREMENTS AND MAIN RESULTS During 8-year follow-up all-cause mortality rate was 15%. Although 4% of the subjects with %LAA less than 3 died, 18% with %LAA 3-10 and 44% with %LAA greater than or equal to 10 died. After adjustment, the comparable percentile subjects with medium and high emphysema had 19 months shorter survival than subjects who died in the lowest emphysema category. Subjects with %LAA greater than or equal to 10 had 33 and 37 months shorter survival than the lowest emphysema category with regard to respiratory and cardiovascular mortality, respectively. No significant associations were found between %LAA and cancer and lung cancer mortality. AWT did not predict mortality independently, but a positive interaction with emphysema was observed. CONCLUSIONS AWT affected mortality with increasing degree of emphysema, whereas CT measure of emphysema was a strong independent mortality predictor.

Indoor exposures and respiratory symptoms in a Norwegian community sample

Background: Limited data are available on the effect of a poor indoor climate on the respiratory health of adults. No data are available regarding the contribution of indoor exposures to the burden of respiratory symptoms in the population. Methods: In 1996–7 a community sample of 3181 adults aged 26–82 years was invited to participate in a survey on indoor climate and respiratory health in Hordaland County, Norway. 2401 subjects agreed to take part. Logistic regression was used to examine the relationship between eight markers of indoor exposure and physician diagnosed asthma and five respiratory symptoms, after adjustment for sex, age, smoking, educational level, smoking habits, pack years, and occupational airborne exposure. Results: Mould exposure was associated with all the respiratory symptoms; the adjusted odds ratios (OR) varied from 1.6 (95% confidence interval (CI) 1.0 to 2.4) for cough with phlegm to 2.3 (95% CI 1.4 to 3.9) for grade 2 dyspnoea. Keeping a cat or dog in childhood was associated with grade 2 dyspnoea and attacks of dyspnoea, with adjusted ORs of 1.3 (95% CI 1.0 to 1.7) and 1.4 (95% CI 1.1 to 1.8), respectively. Having a fitted carpet in the bedroom was negatively associated with three of the five respiratory symptoms. 3–5% of the frequency of the respiratory symptoms in the study population could be attributed to exposure to visible moulds. Conclusion: Mould exposure is an independent risk factor for several respiratory symptoms in a general population covering a wide age span, but it makes only a small contribution to the respiratory symptom burden in the population at large.

Respiratory health in cleaners in Northern Europe : is susceptibility established in early life?

Rationale There is some evidence that maternal smoking increases susceptibility to personal smoking’s detrimental effects. One might question whether early life disadvantage might influence susceptibility to occupational exposure. Objectives In this cross-sectional study we investigated respiratory symptoms, asthma and self-reported chronic obstructive pulmonary disease (COPD) as related to working as a cleaner in Northern European populations, and whether early life factors influenced susceptibility to occupational cleaning’s unhealthy effects. Methods The RHINE III questionnaire study assessed occupational cleaning in 13,499 participants. Associations with respiratory symptoms, asthma and self-reported COPD were analysed with multiple logistic regressions, adjusting for sex, age, smoking, educational level, parent´s educational level, BMI and participating centre. Interaction of occupational cleaning with early life disadvantage (maternal smoking, severe respiratory infection <5 years, born during winter months, maternal age at birth >35 years) was investigated. Main Results Among 2138 ever-cleaners the risks of wheeze (OR 1.4, 95% CI 1.3–1.6), adult-onset asthma (1.5 [1.2–1.8]) and self-reported COPD (1.7 [1.3–2.2]) were increased. The risk increased with years in occupational cleaning (adult-onset asthma: ≤1 year 0.9 [0.7–1.3]; 1–4 years 1.5 [1.1–2.0]; ≥4 years 1.6 [1.2–2.1]). The association of wheeze with cleaning activity ≥4 years was significantly stronger for those with early life disadvantage than in those without (1.8 [1.5–2.3] vs. 1.3 [0.96–1.8]; pinteraction 0.035). Conclusions Occupational cleaners had increased risk of asthma and self-reported COPD. Respiratory symptom risk was particularly increased in persons with factors suggestive of early life disadvantage. We hypothesize that early life disadvantage may increase airway vulnerability to harmful exposure from cleaning agents later in life.

Systemic mannose-binding lectin is not associated with Chronic Obstructive Pulmonary Disease.

Mannose-binding lectin (MBL) deficiency is associated with increased susceptibility to airways infections and autoimmunity. We examined whether MBL deficiency was more common in COPD patients, and whether MBL deficiency was associated with COPD severity. 415 COPD patients and 231 healthy subjects, aged 40-75, were examined in 2006/07. Plasma MBL levels were determined by ELISA. Low or deficient MBL levels were defined as plasma levels below 500ng/mL or 100ng/mL respectively. Logistic regression models determined factors associated with MBL deficiency; with explanatory variables study category, sex, age, smoking, comorbid heart disease, and CRP. For COPD severity, explanatory variables were FEV1, exacerbation history, hypoxia, respiratory symptoms, inhaled steroids, and CRP. 18.2% of healthy subjects and 22.2% of patients had MBL levels below 100ng/mL (p=0.23); 42.9% of healthy subjects and 49.6% of patients had levels below 500ng/mL (p=0.10). After adjustment for co-variables, patients had an OR (95% CI) of 1.26 (0.7, 2.2) for having MBL levels below 100ng/mL compared with healthy subjects, and an OR (95% CI) of 1.06 (0.7, 1.7) for having levels below 500ng/mL. Among the COPD patients, none of the disease variables were associated with MBL deficiency. No association was found between MBL deficiency and COPD or COPD severity.

Validation of self-reported figural drawing scales against anthropometric measurements in adults

OBJECTIVE The aim of the present study was to validate figural drawing scales depicting extremely lean to extremely obese subjects to obtain proxies for BMI and waist circumference in postal surveys. DESIGN Reported figural scales and anthropometric data from a large population-based postal survey were validated with measured anthropometric data from the same individuals by means of receiver-operating characteristic curves and a BMI prediction model. SETTING Adult participants in a Scandinavian cohort study first recruited in 1990 and followed up twice since. SUBJECTS Individuals aged 38-66 years with complete data for BMI (n 1580) and waist circumference (n 1017). RESULTS Median BMI and waist circumference increased exponentially with increasing figural scales. Receiver-operating characteristic curve analyses showed a high predictive ability to identify individuals with BMI > 25·0 kg/m2 in both sexes. The optimal figural scales for identifying overweight or obese individuals with a correct detection rate were 4 and 5 in women, and 5 and 6 in men, respectively. The prediction model explained 74 % of the variance among women and 62 % among men. Predicted BMI differed only marginally from objectively measured BMI. CONCLUSIONS Figural drawing scales explained a large part of the anthropometric variance in this population and showed a high predictive ability for identifying overweight/obese subjects. These figural scales can be used with confidence as proxies of BMI and waist circumference in settings where objective measures are not feasible.

The Association of Gum Bleeding with Respiratory Health in a Population Based Study from Northern Europe

Background There is little knowledge about how oral and respiratory health is interrelated even though the mucosa of the oral cavity and airways constitutes a continuum and the exposures to these are partly similar. Aims To investigate whether gum bleeding is related to asthma, respiratory symptoms and self-reported COPD. Methods A postal questionnaire including questions about respiratory and oral health was sent to general population samples in seven Northern European centres. In 13,409 responders, gum bleeding when brushing teeth was reported always/often by 4% and sometimes by 20%. Logistic regressions accounted for age, smoking, educational level, centre and gender. Effects of BMI, cardio-metabolic diseases, early life factors, gastro-oesophageal reflux, dental hygiene, nasal congestion, and asthma medication were addressed. Results Gum bleeding always/often was significantly associated with ≥3 asthma symptoms (OR 2.58, 95% CI 2.10–3.18), asthma (1.62 [1.23–2.14]) and self-reported COPD (2.02 [1.28–3.18]). There was a dose-response relationship between respiratory outcomes and gum bleeding frequency (≥3 symptoms: gum bleeding sometimes 1.42 [1.25–1.60], often/always 2.58 [2.10–3.18]), and there was no heterogeneity between centres (pheterogeneity = 0.49). None of the investigated risk factors explained the associations. The observed associations were significantly stronger among current smokers (pinteraction = 0.004). Conclusions A consistent link between gum bleeding and obstructive airways disease was observed, not explained by common risk factors or metabolic factors. We speculate that oral pathogens might have unfavourable impact on the airways, and that the direct continuity of the mucosa of the oral cavity and the airways reflects a pathway that might provide novel opportunities for interventions.

Cleaning at Home and at Work in Relation to Lung Function Decline and Airway Obstruction

Rationale: Cleaning tasks may imply exposure to chemical agents with potential harmful effects to the respiratory system, and increased risk of asthma and respiratory symptoms among professional cleaners and in persons cleaning at home has been reported. Long‐term consequences of cleaning agents on respiratory health are, however, not well described. Objectives: This study aimed to investigate long‐term effects of occupational cleaning and cleaning at home on lung function decline and airway obstruction. Methods: The European Community Respiratory Health Survey (ECRHS) investigated a multicenter population‐based cohort at three time points over 20 years. A total of 6,235 participants with at least one lung function measurement from 22 study centers, who in ECRHS II responded to questionnaire modules concerning cleaning activities between ECRHS I and ECRHS II, were included. The data were analyzed with mixed linear models adjusting for potential confounders. Measurements and Main Results: As compared with women not engaged in cleaning (&Dgr;FEV1 = −18.5 ml/yr), FEV1 declined more rapidly in women responsible for cleaning at home (−22.1; P = 0.01) and occupational cleaners (−22.4; P = 0.03). The same was found for decline in FVC (&Dgr;FVC = −8.8 ml/yr; −13.1, P = 0.02; and −15.9, P = 0.002; respectively). Both cleaning sprays and other cleaning agents were associated with accelerated FEV1 decline (−22.0, P = 0.04; and −22.9, P = 0.004; respectively). Cleaning was not significantly associated with lung function decline in men or with FEV1/FVC decline or airway obstruction. Conclusions: Women cleaning at home or working as occupational cleaners had accelerated decline in lung function, suggesting that exposures related to cleaning activities may constitute a risk to long‐term respiratory health.

Pneumothorax size measurements on digital chest radiographs: Intra- and inter- rater reliability

PURPOSE Detailed and reliable methods may be important for discussions on the importance of pneumothorax size in clinical decision-making. Rheas method is widely used to estimate pneumothorax size in percent based on chest X-rays (CXRs) from three measure points. Chois addendum is used for anterioposterior projections. The aim of this study was to examine the intrarater and interrater reliability of the Rhea and Choi method using digital CXR in the ward based PACS monitors. MATERIALS AND METHODS Three physicians examined a retrospective series of 80 digital CXRs showing pneumothorax, using Rhea and Chois method, then repeated in a random order two weeks later. We used the analysis of variance technique by Eliasziw et al. to assess the intrarater and interrater reliability in altogether 480 estimations of pneumothorax size. RESULTS Estimated pneumothorax sizes ranged between 5% and 100%. The intrarater reliability coefficient was 0.98 (95% one-sided lower-limit confidence interval C 0.96), and the interrater reliability coefficient was 0.95 (95% one-sided lower-limit confidence interval 0.93). CONCLUSION This study has shown that the Rhea and Choi method for calculating pneumothorax size has high intrarater and interrater reliability. These results are valid across gender, side of pneumothorax and whether the patient is diagnosed with primary or secondary pneumothorax.