Respiratory symptoms and 30 year mortality from obstructive lung disease and pneumonia

Association between body mass index and respiratory symptoms in US adults: a national cross-sectional study

The correlation between body mass index (BMI) and the development of cough, shortness of breath, and dyspnea is unclear. Therefore, this study aimed to investigate the association between these parameters. Data from individuals who participated in the National Health and Nutrition Examination Survey between 2003 and 2012 were analyzed. Weighted logistic regression analysis and smoothed curve fitting were used to examine the correlation between BMI and respiratory symptoms. In addition, the relationship between BMI, chronic obstructive pulmonary disease (COPD), and bronchial asthma was examined. Stratified analysis was used to discover inflection points and specific groups. Weighted logistic regression and smoothed curve fitting revealed a U-shaped relationship between BMI and respiratory symptoms. The U-shaped relationship in BMI was also observed in patients with bronchial asthma and COPD. Stratified analysis showed that the correlation between BMI and wheezing and dyspnea was influenced by race. In addition, non-Hispanic black individuals had a higher risk of developing cough than individuals of the other three races [OR 1.040 (1.021, 1.060), p < 0.0001], and they also exhibited an inverted U-shaped relationship between BMI and bronchial asthma. However, the association of BMI with cough, wheezing, dyspnea, COPD, and asthma was not affected by sex. High or low BMI was associated with cough, shortness of breath, and dyspnea, and has been linked to bronchial asthma and COPD. These findings provide new insights into the management of respiratory symptoms and respiratory diseases.

Correlation between serum iron levels and pulmonary function: A cross-sectional analysis based on NHANES database 5319 cases

Pulmonary function, one of the main indicators of respiratory system assessment, is difficult to measure in specific cases. The study investigated the association between serum iron levels and pulmonary function. The cross-sectional study was conducted using data from 5319 participants from the 2010-2012 National Health and Nutrition Examination Survey. Forced expiratory volume in 1 second (FEV1), forced vital capacity (FVC), and forced expiratory flow from 25% to 75% of FVC were used as indicators of pulmonary function to analyze the relationship of serum iron and pulmonary function. Univariate and stratified analyses, multiple equation regression analysis, smoothed curve fitting analysis, and threshold effect analysis were performed to explore the relationship between pulmonary function and serum iron concentrations. Threshold effect analysis revealed a nonlinear relationship between serum iron levels and FVC, as well as FEV1, with inflection points observed at 8.1 (µmol/L) and 8.4 (µmol/L), respectively. When serum iron concentrations fell below the inflection point, there was no statistically significant relationship between serum iron and FVC (P = .065) or FEV1 (P = .095) (P > .005). However, when serum iron concentrations exceeded the inflection point, both FVC (β = 6.87; 95% confidence interval [CI] = 3.95, 9.79; P < .0001) and FEV1 (β = 7.09; 95% CI = 4.54, 9.64; P < .0001) exhibited a positive correlation with increasing serum iron levels. Additionally, forced expiratory flow from 25% to 75% of FVC (mL/s) demonstrated a positive association with serum iron (β = 6.72; 95% CI = 2.30, 11.13; P = .0029). Serum iron level was positively correlated with pulmonary function within a certain range of serum iron concentration. Serum iron level may be a protective factor for pulmonary function.

The impact of sport on the physical, psychological and social wellbeing of people with chronic breathlessness: A mixed-methods systematic review

OBJECTIVE

Sport participation may have quality-of-life benefits for people with chronic breathlessness; however, its feasibility and impact on health are unknown. We aimed to synthesise the scientific literature concerning the impact of sport for people with chronic breathlessness.

DATA SOURCES

Searches of MEDLINE, CINAHL, PsycINFO, Embase, SPORTDiscus and Google Scholar were conducted (May 2023).

REVIEW METHODS

Studies were included if they assessed the impact of sport with participants who were likely to suffer from chronic breathlessness due to an underlying condition (e.g. severe asthma, heart failure). A convergent-segregated approach to synthesis in accordance with the JBI methodology for mixed-methods reviews was utilised, including meta-analytic and meta-aggregation analyses.

RESULTS

A total of 22 studies met the inclusion criteria. Studies sampled 1017 participants from 13 different countries, with sample sizes ranging from 5 to 185. Causes of breathlessness consisted of chronic respiratory diseases (9 studies) and coronary heart disease (13 studies). Design-wise, 18 reported quantitative methods, 3 qualitative, and 1 mixed-methods.

CONCLUSIONS

Sports were well-adhered to with only minor/unrelated adverse events reported. Improvements in exercise capacity were observed although there was no impact on health-related quality of life. Other quantitative outcomes extracted varied widely across studies, making it difficult to draw firm conclusions. Participation in sports was reliably recorded at intensity consistent with moderate-to-vigorous activity despite being self-paced. Qualitative themes emphasised the positive elements of sport participation, namely, social cohesion, the capacity to incorporate culture, and the idea that participation is enjoyable rather than a necessary chore to maintain one's health.

Respiratory symptoms and respiratory deaths: A multi-cohort study with 45 years observation time

This study determined the association between respiratory symptoms and death from respiratory causes over a period of 45 years. In four cohorts of random samples of Norwegian populations with 103,881 participants, 43,731 persons had died per 31 December 2016. In total, 5,949 (14%) had died from respiratory diseases; 2,442 (41%) from lung cancer, 1,717 (29%) chronic obstructive pulmonary disease (COPD), 1,348 (23%) pneumonia, 119 (2%) asthma, 147 (2%) interstitial lung disease and 176 (3%) other pulmonary diseases. Compared with persons without respiratory symptoms the multivariable adjusted hazard ratio (HR) for lung cancer deaths increased with score of breathlessness on effort and cough and phlegm, being 2.6 (95% CI 2.1–3.2) for breathlessness score 3 and 2.1 (95% CI 1.7–2.5) for cough and phlegm score 5. The HR of COPD death was 6.4 (95% CI 5.4–7.7) for breathlessness score 3 and 3.0 (2.4–3.6) for cough and phlegm score 5. Attacks of breathlessness and wheeze score 2 had a HR of 1.6 (1.4–1.9) for COPD death. The risk of pneumonia deaths increased also with higher breathlessness on effort score, but not with higher cough and phlegm score, except for score 2 with HR 1.5 (1.2–1.8). In this study with >2.4 million person-years at risk, a positive association was observed between scores of respiratory symptoms and deaths due to COPD and lung cancer. Respiratory symptoms are thus important risk factors, which should be followed thoroughly by health care practitioners for the benefit of public health.

Chronic breathlessness and sleep problems: a population-based survey

OBJECTIVES

This study aimed to explore the relationship (presence and severity) between chronic breathlessness and sleep problems, independently of diagnoses and health service contact by surveying a large, representative sample of the general population.

SETTING

Analysis of the 2017 South Australian Health Omnibus Survey, an annual, cross-sectional, face-to-face, multistage, clustered area systematic sampling survey carried out in Spring 2017.Chronic breathlessness was self-reported using the ordinal modified Medical Research Council (mMRC; scores 0 (none) to 4 (housebound)) where breathlessness has been present for more than 3 of the previous 6 months. 'Sleep problems-ever' and 'sleep problem-current' were assessed dichotomously. Regression models were adjusted for age; sex and body mass index (BMI).

RESULTS

2900 responses were available (mean age 48.2 years (SD=18.6); 51% were female; mean BMI 27. 1 (SD=5.9)). Prevalence was: 2.7% (n=78) sleep problems-past; 6.8% (n=198) sleep problems-current and breathlessness (mMRC 1-4) was 8.8% (n=254). Respondents with sleep problemspast were more likely to be breathless, older with a higher BMI and sleep problems-present also included a higher likelihood of being female.After adjusting for age, sex and BMI, respondents with chronic breathlessness had 1.9 (95% CI=1.0 to 3.5) times the odds of sleep problems-past and sleep problems-current (adjusted OR=2.3; 95% CI=1.6 to 3.3).

CONCLUSIONS

There is a strong association between the two prevalent conditions. Future work will seek to understand if there is a causal relationship using validated sleep assessment tools and whether better managing one condition improves the other.

How to Assess Breathlessness in Chronic Obstructive Pulmonary Disease

Activity-related breathlessness is the most problematic symptom of chronic obstructive pulmonary disease (COPD), arising from complex interactions between peripheral pathophysiology (both pulmonary and non-pulmonary) and central perceptual processing. To capture information on the breathlessness experienced by people with COPD, many different instruments exist, which vary in applicability depending on the purpose and context of assessment. We reviewed common breathlessness assessment instruments, providing recommendations around how to assess the severity of, or change in, breathlessness in people with COPD in daily life or in response to exercise provocation. A summary of 14 instruments for the assessment of breathlessness severity in daily life is presented, with 11/14 (79%) instruments having established minimal clinically importance differences (MCIDs) to assess and interpret breathlessness change. Instruments varied in their scope of assessment (functional impact of breathlessness or the severity of breathlessness during different activities, focal periods, or alongside other common COPD symptoms), dimensions of breathlessness assessed (uni-/multidimensional), rating scale properties and intended method of administration (self-administered versus interviewer led). Assessing breathlessness in response to an acute exercise provocation overcomes some limitations of daily life assessment, such as recall bias and lack of standardized exertional stimulus. To assess the severity of breathlessness in response to an acute exercise provocation, unidimensional or multidimensional instruments are available. Borg's 0-10 category rating scale is the most widely used instrument and has estimates for a MCID during exercise. When assessing the severity of breathlessness during exercise, measures should be taken at a standardized submaximal point, whether during laboratory-based tests like cardiopulmonary exercise testing or field-based tests, such as the 3-min constant rate stair stepping or shuttle walking tests. Recommendations are provided around which instruments to use for breathlessness assessment in daily life and in relation to exertion in people with COPD.

Breathlessness, Anxiety, Depression, and Function-The BAD-F Study: A Cross-Sectional and Population Prevalence Study in Adults

CONTEXT

Breathlessness is associated with depression, but its relationship to anxiety or impaired function is less clear.

OBJECTIVES

This study evaluated associations between chronic breathlessness and anxiety, depression, and functional status in the general population.

METHODS

This cross-sectional study of consenting adults (18 years and older) used an online survey. Quota sampling (n = 3000) was used reflecting the 2016 national census for sex, age, and place of residence. Other data included Four-Item Patient Health Questionnaire for depression and anxiety, the modified Medical Research Council (mMRC) Breathlessness Scale, and the Australia-modified Karnofsky Performance Scale. Multinomial logistic regression assessed predictors.

RESULTS

About 2977 respondents had all relevant scores (female 51.2%; median age 45.0 [range 18-92]). Prevalence of breathlessness (mMRC ≥2) was 2.4%, anxiety 6.0%, depression 2.7%, coexisting anxiety/depression 6.1%, and poorer functional status (Australia-modified Karnofsky Performance Scale ≤60) 1.6%. In multinomial regression, depression, anxiety, and coexisting anxiety/depression were predicted by younger age, longer duration of breathlessness, and poorer functional status. The highest proportions of people with breathlessness were found in the coexisting anxiety/depression group (10.6%) and depression only group (8.8%). Poorest function was in the coexisting anxiety/depression group with 11.6%. The relationship between poorer functional status and coexisting anxiety/depression was significant (odds ratio 0.90; 95% CI 0.89, 0.92). Adjusted odds ratio for breathlessness and depression only was 3.0 (95% CI 1.2, 7.8).

CONCLUSION

Clinically important breathlessness (mMRC ≥2) was associated with depression, anxiety, and coexisting anxiety/depression. Poorer function that is associated with psychological morbidity in the general population requires further research.

Breathlessness in Elderly Adults During the Last Year of Life Sufficient to Restrict Activity: Prevalence, Pattern, and Associated Factors

OBJECTIVES

To investigate relationships between age, clinical characteristics, and breathlessness sufficient to have people spend at least half a day a month in bed or to cut down on their usual activities (restricting breathlessness) during the last year of life.

DESIGN

Secondary data analysis.

SETTING

General community.

PARTICIPANTS

Nondisabled persons aged 70 and older (N=754).

MEASUREMENTS

Monthly telephone interviews were conducted to determine the occurrence of restricting breathlessness. The primary outcome was percentage of months with restricting breathlessness reported during the last year of life.

RESULTS

Data regarding breathlessness were available for 548 of 589 (93.0%) participants who died (mean age 86.7, range 71-106; 38.8% male) between enrollment (March 1998 to October 1999) and June 2013; 311 of these (56.8%) reported restricting breathlessness at some point during the last year of life, but none reported it every month. Frequency increased in the months closer to death, irrespective of cause. Restricting breathlessness was associated with anxiety (0.25 percentage points greater in months with breathlessness per percentage point months reported anxiety, 95% confidence interval (CI)=0.16-0.34, P<.001), depression (0.14, 95% CI=0.05-0.24, P=.003), and mobility problems (0.07, 0.03-0.1, P<.001). Percentage months of restricting breathlessness was greater if chronic lung disease was noted at the most-recent comprehensive assessment (6.62 percentage points, 95% CI=4.31-8.94, P<.001), heart failure (3.34 percentage points, 95% CI=0.71-5.97, P=.01), and ex-smoker status (3.01 percentage points, 95% CI=0.94-5.07, P=.004) but decreased with older age (-0.19 percentage points, 95% CI=-0.37 to -0.02, P=.03).

CONCLUSION

Restricting breathlessness increased in this elderly population in the months preceding death from any cause. Breathlessness should be assessed and managed in the context of poor prognosis.

Can variability in the effect of opioids on refractory breathlessness be explained by genetic factors?

OBJECTIVES

Opioids modulate the perception of breathlessness with a considerable variation in response, with poor correlation between the required opioid dose and symptom severity. The objective of this hypothesis-generating, secondary analysis was to identify candidate single nucleotide polymorphisms (SNP) from those associated with opioid receptors, signalling or pain modulation to identify any related to intensity of breathlessness while on opioids. This can help to inform prospective studies and potentially lead to better tailoring of opioid therapy for refractory breathlessness.

SETTING

17 hospice/palliative care services (tertiary services) in 11 European countries.

PARTICIPANTS

2294 people over 18 years of age on regular opioids for pain related to cancer or its treatment.

PRIMARY OUTCOME MEASURES

The relationship between morphine dose, breathlessness intensity (European Organisation for Research and Treatment of Cancer Core Quality of Life Questionnaire; EORTCQLQC30 question 8) and 112 candidate SNPs from 25 genes (n=588).

SECONDARY OUTCOME MEASURES

The same measures for people on oxycodone (n=402) or fentanyl (n=429).

RESULTS

SNPs not in Hardy-Weinberg equilibrium or with allele frequencies (<5%) were removed. Univariate associations between each SNP and breathlessness intensity were determined with Benjamini-Hochberg false discovery rate set at 20%. Multivariable ordinal logistic regression, clustering over country and adjusting for available confounders, was conducted with remaining SNPs. For univariate morphine associations, 1 variant on the 5-hydroxytryptamine type 3B (HTR3B) gene, and 4 on the β-2-arrestin gene (ARRB2) were associated with more intense breathlessness. 1 SNP remained significant in the multivariable model: people with rs7103572 SNP (HTR3B gene; present in 8.4% of the population) were three times more likely to have more intense breathlessness (OR 2.86; 95% CIs 1.46 to 5.62; p=0.002). No associations were seen with fentanyl nor with oxycodone.

CONCLUSIONS

This large, exploratory study identified 1 biologically plausible SNP that warrants further study in the response of breathlessness to morphine therapy.

The Population Burden of Chronic Symptoms that Substantially Predate the Diagnosis of a Life-Limiting Illness

Many people in our communities live with symptoms for years or decades, something of relevance to hospice/palliative care clinicians and researchers. The proportion of people in the community at large who have a chronic symptom is likely to approximate the proportion of people referred to hospice/palliative care services with that same chronic symptom that pre-dates their life-limiting illness. Such patients may have different responsiveness to, and expectations from, symptomatic therapies, thus requiring more advanced approaches to symptom control. For researchers evaluating the impact of hospice/palliative care services, failing to account for people with long-term refractory symptoms pre-dating their life-limiting illness may systematically underestimate services' benefits. Observational symptom prevalence studies reported in hospice/palliative care to date have not accounted for people with long-term refractory symptoms, potentially systematically overestimating symptoms attributed to life-limiting illnesses. Cross-sectional community prevalence rates of key chronic refractory symptoms largely unrelated to their life-limiting illness reflect the likely prevalence on referral to hospice/palliative care: fatigue (up to 35%); pain (12%-31%); pain with neuropathic characteristics (9%); constipation (2%-29%); dyspnea (4%-9%); cognitive impairment (>10% of people >65 years old; >30% of people >85 years old); anxiety (4%); and depression (lifetime incidence 2%-15%; one year prevalence 3%). Prospective research is needed to establish (1) the prevalence and severity of chronic symptoms that pre-date the diagnosis of a life-limiting illness in people referred to hospice/palliative care services, comparing this to whole-of-population estimates; and (2) whether this group is disproportionately represented in people with refractory symptoms.

Long-term prognosis in community-acquired pneumonia

PURPOSE OF REVIEW

Pneumonia is considered the leading infectious diseases cause of death and the seventh leading cause of death overall in the US. There is significant interest in understanding the relationship between community-acquired pneumonia (CAP) and mortality.

RECENT FINDINGS

Most clinical studies examining patients with CAP have used an arbitrary in-hospital or 30-day mortality as a short-term mortality clinical end point. However, long-term mortality (arbitrary >3 months) factors, incidence, prediction, and implications on patient care are important issues that require further evaluation in patients with CAP. This review focuses on the most recent literature assessing the importance and the frequency of long-term associated outcomes in patients with CAP, the risk factors, and possible implications for future strategies. Multiple risk factors that include age, sex, comorbid conditions, type of pneumonia, and severity of illness are associated with higher long-term mortality. In addition, several biomarkers were demonstrated to be independently associated with long-term mortality.

SUMMARY

Despite advances in the understanding of long-term mortality among CAP patients, there is still a high unacceptable long-term mortality. Public health programs should address this important gap, considering the high level of complexity factors in patients with CAP.

Palliative care for patients with chronic obstructive pulmonary disease: current perspectives

Chronic obstructive pulmonary disease (COPD) is a chronic respiratory illness with a myriad of disabling symptoms and a decline in the functional parameters that affect the quality of life. The mortality and morbidity associated with severe COPD is high and the patients are mostly housebound and in need of continuous care and support. The uncertain nature of its prognosis makes the commencement of palliative care and discussion of end-of-life issues difficult even in the advanced stage of the disease. This is often compounded by inadequate communication and counseling with patients and their relatives. The areas that may improve the quality of care include the management of dyspnea, oxygen therapy, nutritional support, antianxiety, and antidepressant treatment, and advance care planning. Hence, it is necessary to pursue a holistic care approach for palliative care services along with disease-specific medical management in all such patients to improve the quality of life in end-stage COPD.

The ability of self-rated health to predict mortality among community-dwelling elderly individuals differs according to the specific cause of death: data from the NEDICES cohort

BACKGROUND

The biomedical and psychosocial mechanisms underlying the relationship between self-rated health (SRH) and mortality in elderly individuals remain unclear.

OBJECTIVE

To assess the association between different measurements of subjective health (global, age-comparative, and time-comparative SRH) and cause-specific mortality.

METHODS

Neurological Disorders in Central Spain (NEDICES) is a prospective population-based survey of the prevalence and incidence of major age-associated conditions. Data on demographic and health-related variables were collected from 5,278 subjects (≥65 years) in the baseline questionnaire. Thirteen-year mortality and cause of death were obtained from the National Death Registry. Adjusted hazard ratios (aHR) for SRH and all-cause and cause-specific mortality were estimated by Cox proportional hazard models.

RESULTS

At baseline, 4,958 participants (93.9%) answered the SRH questionnaire. At the end of follow-up, 2,468 (49.8%) participants had died, of whom 723 (29.2%) died from cardiovascular diseases, 609 (24.7%) from cancer, and 359 (14.5%) from respiratory diseases. Global SRH independently predicted all-cause mortality (aHR for 'poor or very poor' vs. 'very good' category: 1.39; 95% confidence interval (CI): 1.15-1.69). Analysis of cause-specific mortality revealed that global SRH was an independent predictor for death due to respiratory diseases (aHR for 'poor or very poor' vs. 'very good' category: 2.61; 95% CI: 1.55-4.39), whereas age-comparative SRH exhibited a gradient effect on the risk of death due to stroke. Time-comparative SRH provided small additional predictive value.

CONCLUSIONS

The predictive ability of SRH for mortality largely differs according to the specific cause of death, with the strongest associations found for respiratory disease and stroke mortality.

Dyspnea severity, changes in dyspnea status and mortality in the general population: the Vlagtwedde/Vlaardingen study

Dyspnea is a predictor of mortality. The effects of dyspnea severity and changes in dyspnea status on all-cause and cause-specific mortality remain unclear. The Vlagtwedde/Vlaardingen study started in 1965 and subjects were re-examined every 3 years until 1989/1990. Vital status of all 8,465 subjects on December 31st, 2008 was assessed. Associations between mortality and dyspnea severity and changes in dyspnea status were investigated using Cox regression adjusted for gender, age, FEV1% predicted, place of residence, smoking and BMI. After 43 years of follow-up, 2,883 (39%) of 7,360 subjects examined for dyspnea severity had died, 1,386 (19%) due to cardiovascular disease, 267 (4%) due to chronic obstructive pulmonary disease (COPD). Subjects with moderate and severe dyspnea had increased all-cause and cardiovascular mortality [moderate: HR=1.3 (95% CI 1.2-1.5) and 1.4 (1.1-1.6), severe: 1.5 (1.1-2.0) and 1.9 (1.3-2.6) respectively] compared to asymptomatics. Severe dyspnea was significantly associated with COPD mortality [3.3 (2.0-5.2)]. Subjects who lost dyspnea had hazard ratios for all-cause and cause-specific mortality comparable to asymptomatics. Persistent dyspnea and dyspnea development were risk factors for all-cause, cardiovascular and COPD mortality [persistent: 2.0 (1.4-2.8), 1.9 (1.2-3.3) and 3.3 (1.2-8.9), development: 1.5 (1.2-1.8), 2.0 (1.5-2.6) and 3.8 (2.3-6.3) respectively]. Additionally, dyspnea effects on mortality were more pronounced in overweight/obese and older subjects and in subjects with better lung function. These results show that dyspnea is associated with mortality in a severity-dependent manner. Furthermore this study is the first showing that dyspnea remission normalizes mortality risk. Having or developing dyspnea is a risk factor for mortality.

Cost-effectiveness of screening for abdominal aortic aneurysm in the Netherlands and Norway

Background

The aim of this study was to determine the cost-effectiveness of ultrasound screening for abdominal aortic aneurysm (AAA) in men aged 65 years, for both the Netherlands and Norway.

Methods

A Markov model was developed to simulate life expectancy, quality-adjusted life-years, net health benefits, lifetime costs and incremental cost-effectiveness ratios for both screening and no screening for AAA. The best available evidence was retrieved from the literature and combined with primary data from the two countries separately, and analysed from a national perspective. A threshold willingness-to-pay (WTP) of €20 000 and €62 500 was used for data from the Netherlands and Norway respectively.

Results

The additional costs of the screening strategy compared with no screening were €421 (95 per cent confidence interval 33 to 806) per person in the Netherlands, and the additional life-years were 0·097 (−0·180 to 0·365), representing €4340 per life-year. For Norway, the values were €562 (59 to 1078), 0·057 (−0·135 to 0·253) life-years and €9860 per life-year respectively. In Norway the results were sensitive to a decrease in the prevalence of AAA in 65-year-old men to 1 per cent, or lower. Probabilistic sensitivity analyses indicated that AAA screening has a 70 per cent probability of being cost-effective in the Netherlands with a WTP threshold of €20 000, and 70 per cent in Norway with a threshold of €62 500.

Conclusion

Using this model, screening for AAA in 65-year-old men would be highly cost-effective in both the Netherlands and Norway.

The association between symptoms and exposure is stronger in dropouts than in non-dropouts among employees in Norwegian smelters: a five-year follow-up study

Purpose

We have investigated the association between respiratory symptoms and dust exposure among employees in 18 Norwegian smelters using a longitudinal design.

Methods

All employees (N = 3,084) were examined annually for 5 years (12,996 health examinations). At each examination, the subjects reported if they had respiratory symptoms, coded as 1 (yes) or 0 (no), on a respiratory questionnaire. Symptom score was constructed as the sum of symptoms (0–5). Full-time workers in the production line were classified as line operators; subjects never exposed in the production line were regarded as non-exposed. The remaining individuals were classified as non-line operators. A job-exposure matrix regarding dust exposure was also available. Analyses of repeated measurements were performed using generalised linear mixed model with log-link (Poisson regression). Adjustments were made for overdispersion.

Results

The mean age at inclusion was 39.0 years, and 89% were men. The median dust exposure in tertiles 1–3 was 0.19, 1.76 and 3.47 mg/m³. The longitudinal analyses showed that the association between symptoms-score ratio (SSR) and job category was significantly stronger in dropouts compared with non-dropouts (p = 0.01). Among the dropouts, SSR was 1.61 (95% confidence interval: 1.27–2.05) and 1.39 (1.09–1.77) in line operators and non-line operators compared with non-exposed employees, respectively. The corresponding SSR for subjects who completed the study was 1.13 (1.01–1.27) and 1.12 (1.00–1.26), respectively. Similarly, among the dropouts, the SSR between the second and the first tertile was 1.28 (1.05–1.55) and 1.37 (1.13–1.66) between the third tertile and the first tertile.

Conclusions

Line operators had more respiratory symptoms than non-exposed employees. This effect was significantly stronger in dropouts than in those who continued their jobs, indicating that there is a selection of subjects without respiratory symptoms in this industry.

Mortality from non-malignant respiratory diseases among workers in the Norwegian silicon carbide industry: associations with dust exposure

Objectives

Increased mortality from asthma, chronic bronchitis and emphysema has previously been reported among workers in the silicon carbide (SiC) industry. The objective of the present study was to evaluate the influence of specific exposure factors on mortality from obstructive lung diseases (OLD), using a newly revised job-exposure matrix.

Materials and methods

1687 long-term workers employed in 1913–2003 in the Norwegian SiC industry were characterised with respect to cumulative exposure to quartz, cristobalite, SiC particles and SiC fibres. Standardised mortality ratios (SMRs) for underlying causes of death, 1951–2007, were calculated stratified by category of cumulative exposure, and Poisson regression analyses of OLD were performed using cumulative exposure variables.

Results

An increased total mortality (SMR 1.1, 95% CI 1.0 to 1.2) and increased mortality from cancer, non-malignant respiratory diseases and external factors, were observed. The SMR of OLD was increased at the highest level of cumulative exposure to all investigated exposure factors. In the internal analyses, a twofold increased risk of OLD was observed with increasing levels of cumulative exposure to SiC particles. In a multivariate model, SiC particles showed the most stable increased risk estimate when controlled for other exposure factors, among workers with less than 15 years of employment. Among workers with more than 15 years of employment, crystalline silica, primarily cristobalite, seemed to be the most important exposure factor.

Conclusion

Exposure to SiC and crystalline silica may contribute to OLD development among SiC industry workers in different time windows, and possibly through different mechanisms.

Associations between mortality, asthma, and health-related quality of life in an elderly cohort of Swedes

BACKGROUND

Asthma is a common chronic health condition among the elderly and an important cause of morbidity and mortality. Some studies show that subjective assessments of health-related quality of life (HRQL) are important predictors of mortality and survival. The primary aim of this study was to investigate whether low HRQL was a predictor of mortality in elderly subjects and whether such an association differed between subjects with and without asthma.

METHODS

In 1990, a cohort in middle Sweden was investigated using a respiratory questionnaire. To assess HRQL, the generic instrument Gothenburg Quality of Life (GQL) was used. The participants were also investigated by spirometry and allergy testing. The present study was limited to the subjects in the oldest age group, aged 60-69 years in 1990, and included 222 subjects with clinically verified asthma, 148 subjects with respiratory symptoms but no asthma or other lung diseases, and 102 subjects with no respiratory symptoms. Mortality in the cohort was followed during 1990-2008.

RESULTS

Altogether, 166 of the 472 subjects in the original cohort had died during the follow-up period of 1990-2008. Mortality was significantly higher in men, in older subjects, in smokers, and subjects with a low forced expiratory volume in one second (FEV(1)). There was, however, no difference in mortality between the asthmatic and the nonasthmatic groups. A higher symptoms score for GQL was significantly related to increased mortality. No association between HRQL and mortality was found when limiting the analysis to the asthmatic group, although the asthmatics had a lower symptom score for GQL compared to the other groups.

CONCLUSION

A higher symptom score in the GQL instrument was significantly related to increased mortality, but this association was not found when analyzing the asthmatic group alone. The negative prognostic implications of a low HRQL in the whole group and the fact that the asthmatic group had a lower HRQL than the other group supports the use of HRQL instruments in clinical health assessments.

Risk factors for chest illness in chronic spinal cord injury: a prospective study

OBJECTIVE

Chest illnesses commonly cause morbidity in persons with chronic spinal cord injury. Risk factors remain poorly characterized because previous studies have not accounted for factors other than spinal cord injury.

DESIGN

Between 1994 and 2005, 403 participants completed a respiratory questionnaire and underwent spirometry. Participants were contacted at a median of 1.7 yrs [interquartile range: 1.3-2.5 yrs] apart over a mean (SD) of 5.1 +/- 3.0 yrs and asked to report chest illnesses that had resulted in time off work, spent indoors, or in bed since prior contact.

RESULTS

In 97 participants, there were 247 chest illnesses (0.12/person-year) with 54 hospitalizations (22%). Spinal cord injury level, completeness of injury, and duration of injury were not associated with illness risk. Adjusting for age and smoking history, any wheeze (relative risk = 1.92; 95% confidence interval: 1.19, 3.08), pneumonia or bronchitis since spinal cord injury (relative risk = 2.29; 95% confidence interval: 1.40, 3.75), and physician-diagnosed chronic obstructive pulmonary disease (relative risk = 2.17; 95% confidence interval: 1.08, 4.37) were associated with a greater risk of chest illness. Each percent-predicted decrease in forced expiratory volume in 1 sec was associated with a 1.2% increase in risk of chest illness (P = 0.030).

CONCLUSIONS

In chronic spinal cord injury, chest illness resulting in time spent away from usual activities was not related to the level or completeness of spinal cord injury but was related to reduced pulmonary function, wheeze, chronic obstructive pulmonary disease, a history of pneumonia and bronchitis, and smoking.

Aspects of healthcare utilisation in self-reported obstructive lung disease

INTRODUCTION

Utilisation of healthcare resources because of pulmonary diseases have previously been presented according to lung function or symptom severity. We aimed to compare the associations of symptoms and lung function to healthcare and social service utilisation in subjects with self-reported obstructive lung diseases (OLDs) (asthma, chronic obstructive pulmonary disease, chronic bronchitis, emphysema).

MATERIALS AND METHODS

Of 2819 participants aged 27-82 years in the Hordaland County Respiratory Health Survey, 200 subjects (7.1%) self-reported OLD. They answered 13 questions on respiratory symptoms and 5 questions on use of healthcare and social services. Altogether, 161 participants (81%) completed post-bronchodilation spirometry.

RESULTS

Use of anti-asthmatic drugs, regular physician's appointment, sick leave payment for the last 12 months, hospital admission for the last 12 months and disability pension were reported by 68%, 63%, 18%, 8% and 7% of those with self-reported OLD, respectively. Twenty per cent of subjects with self-reported OLD had not received any healthcare or social services. In adjusted multivariate logistic regression analyses, increase in the respiratory symptom score was significantly associated with more healthcare and social services. Lower forced expiratory volume in 1 s in % predicted, however, was not significantly associated with more use of healthcare and social services.

CONCLUSION

The majority (80%) of subjects in a general population with self-reported OLD received healthcare services. The utilisation of healthcare and social services was strongly associated to the burden of respiratory symptoms, and, to a lesser degree, to the level and pattern of lung function.

Association between respiratory symptom score and 30-year cause-specific mortality and lung cancer incidence

INTRODUCTION

Respiratory symptoms are among the main reasons why patients make contact with healthcare professionals and they are associated with several diseases.

OBJECTIVE

The aim of this study was to investigate the relationship between respiratory symptoms reported at one time and 30 years cause-specific mortality and incidence of lung cancer in an urban Norwegian population.

MATERIALS AND METHODS

A total of 19 998 men and women, aged 15-70 years, were in 1972 selected from the general population of Oslo. They received a postal respiratory questionnaire (response rate 89%). All were followed for 30 years for end-point mortality and for lung cancer. The association between respiratory symptoms, given as a symptom load, and end point of interest were investigated separately for men and women by multivariable analyses, with adjustment for age, occupational exposure to air pollution and smoking habits.

RESULTS

A total of 6710 individuals died during follow-up. Obstructive lung diseases (OLDs) and pneumonia accounted for 250 and 293 of the total deaths, respectively. Ischaemic heart disease (IHD) accounted for 1572; stroke accounted for 653 of all deaths. Lung cancer developed in 352 persons during follow-up. The adjusted hazard ratio for mortality from OLD and pneumonia, IHD and stroke increased in a dose-response manner with symptom score, more strongly for OLD and IHD than for pneumonia and stroke.

CONCLUSIONS

Respiratory symptoms were positively associated with mortality from OLD, pneumonia, IHD and stroke, and incidence of lung cancer. This association was significant for mortality from OLD and IHD.

Norwegian population surveys on respiratory health in adults: objectives, design, methods, quality controls and response rates

BACKGROUND AND AIMS

Quantifying the prevalence of asthma, chronic obstructive pulmonary disease (COPD) and restrictive pulmonary diseases in Norway is needed to document the burden of chronic respiratory inflammatory diseases on disability, health care costs and impaired quality of life. To introduce effective interventions for prevention, cure and care, there is a prerequisite to know the environmental causes. Furthermore, using relevant and precise phenotypes from community-based studies are important for detecting molecular-genetic causes for diseases.

METHODS

The Norwegian Population Survey Initiative on Respiratory Health in Adults has, for four decades, applied international standardised methods for the recording of respiratory symptoms, health status, exposure to risk factors, socio-economic factors and the use of health services. Measurements of spirometry, metacholine bronchial responsiveness, transfer factor for carbon monoxide, atopy as well as chest X-ray examinations have been used advocating the internationally accepted methods. All surveys had similar quality controls, supervision and training of the field-worker team.

RESULTS

From 1965 to 1999, random population samples, altogether including 178 690 individuals, have been invited by random sampling to seven surveys on respiratory health in the counties of Oslo (39 998 people) and Hordaland (138 692 people). The surveys were initiated in 1964, 1972, 1985, 1988, 1991 and two in 1998. The age span of those invited persons varied from 15 to 74 years at baseline. It included 43 330 women and 135 537 men. Altogether 130 075 (73%) persons participated by returning an answered questionnaire. Spirometry results are available from 41 335 persons at baseline. A biobank for DNA and blood markers has been established. Data from longitudinally clinical-epidemiological studies were available by 2007, for three surveys after 20 years, 10 years and 6-7 years, and also for parts of three other surveys, while one survey has been examined for cause-specific mortality after 30 years. The response rates of the baseline studies varied from 90% to 68% of those invited and, in general, it has declined over 35 years. The response rate of the longitudinal studies with follow-ups also declined with time after the baseline study.

CONCLUSIONS

Great challenges for future population-based studies are (i) to keep the participation rates high in community studies; (ii) to standardise the basic clinical-epidemiological methods over decades of follow-up and to systematically transfer these methods into new populations with different languages and cultures and (iii) to focus on important research questions on respiratory health for the community.

Impact of respiratory symptoms on lung cancer: 30-year follow-up of an urban population

We investigated the relationship between respiratory symptoms reported at one time and incidence of lung cancer the subsequent 30 years in an urban Norwegian population. A cohort of 19,998 persons, aged 15-70 years living in Oslo, was randomly selected for a respiratory survey in 1972. The response-rate was 89% and 17,670 respondents were followed up. The relationship between respiratory symptoms and lung cancer incidence was investigated separately for each symptom group, symptom score and sex, with adjustment for age, smoking habits and occupational exposure. Lung cancer developed in 352 persons (228 men and 124 women) during follow up. We found a significant positive association between the incidence of lung cancer and cough symptoms in both sexes, asthma-like symptoms among women and dyspnoea when walking uphill among men. The relative risk for lung cancer increased with the number of symptoms reported at baseline and was strongest the first decade and decreased with duration of follow up. This association was more pronounced for non-small cell lung cancer than for small cell lung cancer.

Respiratory symptoms and long-term cardiovascular mortality

BACKGROUND

Our aim was to investigate the association between respiratory symptoms and mortality from ischaemic heart disease (IHD) and stroke in a population during 30 years follow-up.

METHODS

In 1972, 19998 persons aged 15-70 years, living in Oslo, were selected for a respiratory survey (response 89%). Respiratory symptoms were divided into four groups and given a score. The association between respiratory symptoms and mortality from IHD and stroke were investigated separately for men and women, with adjustment for age, occupational exposure to air pollution and smoking habits.

RESULTS

IHD accounted for 1572 and stroke for 653 of all deaths. The adjusted hazard ratio (HR) for mortality from IHD in men varied from 1.3 (95% confidence interval, 1.1-1.5) to 3.0 (2.3-3.8) and in women from 1.2 (1.0-1.5) to 1.9 (1.4-2.5) for cough symptoms and severe dyspnoea, respectively. Symptom score predicted death from IHD, in a dose-response manner. The HR for mortality from stroke varied from 1.0 to 2.3 in men and from 1.1 to 1.5 in women for the symptom groups, but was significant only among men reporting severe dyspnoea and among women reporting moderate dyspnoea. For all respiratory symptoms, the excess risk for cardiovascular mortality decreased during follow-up, but IHD-mortality was still significantly increased the last decade.

CONCLUSION

We found a significant, positive association between respiratory symptoms and 30-year mortality from IHD. The positive association was weaker between respiratory symptoms and long-term mortality from stroke.

Palliative care in chronic obstructive pulmonary disease: a review for clinicians

Chronic obstructive pulmonary disease (COPD) is a progressive condition characterized by airflow obstruction which ultimately kills many patients. It is common in both men and women and there is a 24-30% 5-year survival rate in the UK for those with severe disease. The annual death rate in the UK from COPD approaches that from lung cancer. Patients' symptoms can be improved by drug therapy, but stopping smoking is also an effective way of improving the outcome in patients at all stages of COPD. Predicting prognosis has been difficult in COPD due to the variable illness trajectory. However, assessment of severity of lung function impairment, frequency of exacerbations and requirement for long term oxygen therapy can help identify patients entering the final 12 months of life. Symptom burden and impact on activities of daily living for patients with COPD are comparable with that of cancer patients, and palliative care approaches are equally necessary, yet few publications exist to guide clinicians in this area. An evidence base exists for the management of dyspnoea with oxygen therapy and opioid drugs. There is less evidence for the effective treatment of depression and anxiety, fatigue and pain, and treatment is based on experience and considered best practice. This review discusses the problems that patients experience and offers practical guidance. The management of patients should be shared between primary and secondary care, with multidisciplinary teams being involved at an early stage. Patients and their families require honest and clear communication about the condition and what to expect in the future. The strict application of advance care planning and directives may not be feasible or appropriate, but there is evidence that attitudes towards resuscitation and artificial ventilation can be explored without distress. The requirement by patients and carers for surveillance and timely support is acknowledged, but how to provide such input is as yet unclear, with little evidence to support the widespread implementation of nurse-led management interventions. The hospice movement has become increasingly involved in the management of life-threatening, non-malignant disease and should be involved in the multidisciplinary care of patients dying from COPD.

Palliative care in chronic obstructive pulmonary disease: a review for clinicians

Chronic obstructive pulmonary disease (COPD) is a progressive condition characterized by airflow obstruction which ultimately kills many patients. It is common in both men and women and there is a 24-30% 5-year survival rate in the UK for those with severe disease. The annual death rate in the UK from COPD approaches that from lung cancer. Patients' symptoms can be improved by drug therapy, but stopping smoking is also an effective way of improving the outcome in patients at all stages of COPD. Predicting prognosis has been difficult in COPD due to the variable illness trajectory. However, assessment of severity of lung function impairment, frequency of exacerbations and requirement for long term oxygen therapy can help identify patients entering the final 12 months of life. Symptom burden and impact on activities of daily living for patients with COPD are comparable with that of cancer patients, and palliative care approaches are equally necessary, yet few publications exist to guide clinicians in this area. An evidence base exists for the management of dyspnoea with oxygen therapy and opioid drugs. There is less evidence for the effective treatment of depression and anxiety, fatigue and pain, and treatment is based on experience and considered best practice. This review discusses the problems that patients experience and offers practical guidance. The management of patients should be shared between primary and secondary care, with multidisciplinary teams being involved at an early stage. Patients and their families require honest and clear communication about the condition and what to expect in the future. The strict application of advance care planning and directives may not be feasible or appropriate, but there is evidence that attitudes towards resuscitation and artificial ventilation can be explored without distress. The requirement by patients and carers for surveillance and timely support is acknowledged, but how to provide such input is as yet unclear, with little evidence to support the widespread implementation of nurse-led management interventions. The hospice movement has become increasingly involved in the management of life-threatening, non-malignant disease and should be involved in the multidisciplinary care of patients dying from COPD.