Body weight and mortality in COPD: focus on the obesity paradox

The positive association between overweight, obesity, and cardiovascular and all-cause mortality is well established, even though this relation is typically U shaped with an increased risk also in low-weight subjects. However, being overweight or obese has been associated with a better prognosis in subjects suffering from chronic diseases, id est the "obesity paradox". In both community-dwelling and hospitalized patients with COPD, several studies have reported a significant protective effect of obesity on all-cause mortality, indicating that also in obstructive pulmonary diseases, an obesity paradox may be present. Interestingly, the "paradox" is more evident for subjects with severe bronchial obstruction (i.e., a lower FEV1), while in mild-moderate conditions, the weight-related mortality shows a behavior similar to that observed in the general population. Several factors may confound the relation between COPD, obesity and mortality. The lower FEV1 found in obese people may be linked to a restrictive defect rather than to an obstructive one. Due to the modified chest wall mechanical properties-related to increased fat mass-obese COPD patients may present, respect to their lean counterpart, a lower lung hyperinflation which is associated with higher mortality. The traditional classification of COPD attributes to obese "blue bloaters" a low-grade emphysema in opposition to lean "pink puffers"; the fact that emphysema extent is related to mortality may bias the relationship between weight and survival. It is also to underline that the majority of the studies, consider BMI rather than body composition (a better predictor of mortality) when studying the intriguing relation between weight, COPD, and mortality. Reverse bias has also to be taken into account, hypothesizing that an unintentional weight loss may be the deleterious factor related to mortality, rather than considering obesity a protective one. Further prospective studies are needed to shed light on the complexity of this emerging issue.

LEVEL OF EVIDENCE

Level V: Narrative Review.

Adult eczema in Italy: prevalence and associations with environmental factors

BACKGROUND

Studies on the prevalence of eczema and atopic dermatitis (AD), and on the factors associated with these diseases, have been mostly performed in children, whereas studies on adult populations are lacking.

OBJECTIVES

To determine the prevalence of eczema and AD in the Italian adult population, and to investigate risk factors associated with the disease.

METHODS

A postal screening questionnaire was administered to 18 357 randomly selected subjects aged 20-44 years in the Gene-Environment Interaction in Respiratory Diseases study, which involved seven centres distributed across northern, central and southern Italy. The questionnaire included items on the occurrence of doctor-diagnosed eczema, asthma and hay fever, socio-demographic characteristics and environmental exposures.

RESULTS

In all, 10 464 (57.0%) subjects responded to the questionnaire. The prevalence of current eczema was 8.1% (95% CI: 7.6-8.7%), while the prevalence of eczema with asthma and/or hay fever (EAH), which was adopted as proxy of AD, was 3.4% (95% CI: 3.1-3.8%). About 60% of the subjects with current eczema reported the onset of the disease in adulthood. In multi-variable models, the prevalence of eczema was significantly associated with female sex, older age, living close to industrial plants, high levels of heavy traffic near home and living in central-southern Italy.

CONCLUSIONS

Eczema and EAH are highly prevalent in Italian young adults, especially in women. Our results suggest that adult onset is not unusual, and that environmental factors may influence the occurrence of eczema and EAH.

Lung cancer: can staging improvement ensure a better survival?

Lung cancer is among the most common cancers in the world. Despite advances in defining the molecular mechanisms involved in lung oncogenesis and the remarkable efforts made to improve screening programs for secondary cancer prevention, patients' prognosis remains poor. Moreover, wide international inequalities remain apparent, even among developed countries. Here we analyze and discuss the findings of the extensive work by Walters S et al., recently published in "Thorax", which aimed to clarify whether differences in stage at diagnosis might explain these divergences. A better understanding of why survival differences between different states still exist will facilitate policy design to increase lung cancer overall survival itself and to bring it up to the highest international standards. It is the first international population-based study of lung cancer survival by stage at diagnosis and includes nearly 60,000 patients. By using a well detailed and appropriate statistical approach, authors conclude that improvement in outcomes is primarily related to a proper initial disease staging and that socioeconomic international and interregional inequalities might play a relevant role in this scenario. Our review takes in consideration both the methodological and scientific issues of the paper, focusing on the potential consequences in lung cancer management and on the need, in the post genomic era, of a molecular-based epidemiologic approach.

Trends in the prevalence of asthma and allergic rhinitis in Italy between 1991 and 2010

The prevalence of asthma increased worldwide until the 1990s, but since then there has been no clear temporal pattern. The present study aimed to assess time trends in the prevalence of current asthma, asthma-like symptoms and allergic rhinitis in Italian adults from 1990 to 2010. The same screening questionnaire was administered by mail or phone to random samples of the general population (age 20-44 yrs) in Italy, in the frame of three multicentre studies: the European Community Respiratory Health Survey (ECRHS) (1991-1993; n = 6,031); the Italian Study on Asthma in Young Adults (ISAYA) (1998-2000; n = 18,873); and the Gene Environment Interactions in Respiratory Diseases (GEIRD) study (2007-2010; n = 10,494). Time trends in prevalence were estimated using Poisson regression models in the centres that repeated the survey at different points in time. From 1991 to 2010, the median prevalence of current asthma, wheezing and allergic rhinitis increased from 4.1% to 6.6%, from 10.1% to 13.9% and from 16.8% to 25.8%, respectively. The prevalence of current asthma was stable during the 1990s and increased (relative risk 1.38, 95% CI 1.19-1.59) from 1998-2000 to 2007-2010, mainly in subjects who did not report allergic rhinitis. The prevalence of allergic rhinitis has increased continuously since 1991. The asthma epidemic is not over in Italy. During the past 20 yrs, asthma prevalence has increased by 38%, in parallel with a similar increase in asthma-like symptoms and allergic rhinitis.

ADRB2 Gly16Arg polymorphism, asthma control and lung function decline

Arg/Arg homozygotes for the Gly16Arg polymorphism in the β₂-adrenoreceptor gene (ADRB2) have a reduced response to short-acting β₂-agonists but no effect has been associated with long-acting β₂-agonists (LABAs). We selected 604 subjects with current asthma from the European Community Respiratory Health Study to evaluate whether asthma control and lung function decline were associated with Gly16Arg polymorphism, and to test whether LABA or inhaled corticosteroid (ICS) use modified these effects. There was an increased risk of noncontrolled asthma (OR 1.33, 95% CI 1.01-1.75; p = 0.046) for each Arg allele. Among nonusers of ICS, the odds ratio of noncontrolled asthma among Arg/Arg versus Gly/Gly subjects was 2.73 (95% CI 1.28-5.82; p = 0.009). No increased risk of noncontrolled asthma associated with the Arg allele was observed among ICS and/or LABA users. For each Arg allele, a mean ± se decrease in decline in forced expiratory volume in 1 s of 7.7 ± 2.5 mL·yr⁻¹ was found (p-value for trend 0.003), irrespective of ICS or LABA use. Arg/Arg subjects had an increased risk of bronchial hyperresponsiveness (BHR) versus Gly/Gly subjects, with an odds ratio of 2.51 (95% CI 1.12-5.63; p = 0.025) if they did not use ICS. The Arg allele was associated with poorer asthma control, a steeper lung function decline and BHR. Absence of genotypic effects on asthma control among ICS users may be due to reversed β₂-adrenoreceptor desensitisation.

The Gene-Environment Interactions in Respiratory Diseases (GEIRD) Project

The role of genetic and environmental factors, as well as their interaction, in the natural history of asthma, allergic rhinitis and chronic obstructive pulmonary disease (COPD) is largely unknown. This is mainly due to the lack of large-scale analytical epidemiological/genetic studies aimed at investigating these 3 respiratory conditions simultaneously. The GEIRD project is a collaborative initiative designed to collect information on biomarkers of inflammation and oxidative stress, individual and ecological exposures, diet, early-life factors, smoking habits, genetic traits and medication use in large and accurately defined series of asthma, allergic rhinitis and COPD phenotypes. It is a population-based multicase-control design, where cases and controls are identified through a 2-stage screening process (postal questionnaire and clinical examination) in pre-existing cohorts or new samples of subjects. It is aimed at elucidating the role that modifiable and genetic factors play in the occurrence, persistence, severity and control of inflammatory airway diseases, by way of the establishment of a historical multicentre standardized databank of phenotypes, contributed by and openly available to international epidemiologists. Researchers conducting population-based surveys with standardized methods may contribute to the public-domain case-control database, and use the resulting increased power to answer their own scientific questions.

Quality-of-life and asthma-severity in general population asthmatics: results of the ECRHS II study

BACKGROUND

Health-related quality-of-life (HRQL) has been poorly studied in large samples of asthmatics from the general population. HRQL and its relationship to asthma-severity were assessed among 900 asthmatics enrolled in the European Community Respiratory Health Survey.

METHODS

Among asthmatics, 864 completed the short form-36 (SF-36) questionnaire and 477 also completed the Asthma Quality-of-life Questionnaire (AQLQ). A 4-class asthma-severity scale, combining clinical items, forced expiratory volume in 1 s and the level of treatment and the different asthma-severity components (each of the clinical items and hospitalization) were studied in relation to HRQL.

RESULTS

Mean SF-36 Physical Component Summary (PCS) and Mental Component Summary (MCS) scores (45.5 and 48.8 respectively) were lower than expected in a general population. The mean total AQLQ score was 5.8. The AQLQ score and to a lesser extent the PCS score were significantly related to the 4-class asthma-severity scale, although the risk of having a lower HRQL score did not vary proportionally across the levels of severity. Asthma-severity had no impact on the MCS score. Asthma attack frequency and hospitalization were associated with both total AQLQ and PCS scores, whereas nocturnal symptoms and lung function were more strongly related to the AQLQ and PCS score respectively.

CONCLUSION

In population-based asthmatics, the specific AQLQ questionnaire, and also to a lesser extent the generic SF-36 questionnaire, were sensitive to asthma-severity. Frequencies of asthma attacks, of nocturnal symptoms and hospitalization for asthma have independent impact on HRQL.

The socio-economic burden of asthma is substantial in Europe

BACKGROUND

Few data are available on the asthma burden in the general population. We evaluated the level and the factors associated with the asthma burden in Europe.

METHODS

In 1999-2002, 1152 adult asthmatics were identified in the European Community Respiratory Health Survey (ECRHS)-II and the socio-economic burden (reduced activity days and hospital services utilization in the past 12 months) was assessed.

RESULTS

The asthmatics with a light burden (only a few reduced activity days) were 13.2% (95% CI: 11.4-15.3%), whereas those with a heavy burden (many reduced activity days and/or hospital services utilization) were 14.0% (95% CI: 12.1-16.1%). The burden was strongly associated with disease severity and a lower quality of life. Obese asthmatics had a significantly increased risk of a light [relative risk ratio (RRR) = 2.17; 95% CI: 1.18-4.00] or a heavy burden (RRR = 2.77; 95% CI: 1.52-5.05) compared with normal/underweight subjects. The asthmatics with frequent respiratory symptoms showed a threefold (RRR = 2.74; 95% CI: 1.63-4.61) and sixfold (RRR = 5.76; 95% CI: 3.25-10.20) increased risk of a light or a heavy burden compared with asymptomatic asthmatics, respectively. Moreover, the lower the forced expiratory volume in 1 s % predicted, the higher the risk of a heavy burden. The coexistence with chronic cough/phlegm only increased the risk of a heavy burden (RRR = 1.88; 95% CI: 1.16-3.06). An interaction was found between gender and IgE sensitization, with nonatopic asthmatic females showing the highest risk of a heavy burden (21.6%; 95% CI: 16.9-27.1%).

CONCLUSIONS

The asthma burden is substantial in Europe. A heavy burden is more common in asthmatics with obesity, frequent respiratory symptoms, low lung function, chronic cough/phlegm and in nonatopic females.

Changes in the use of anti-asthmatic medication in an international cohort

The aim of this study was to describe changes in pharmacotherapy for asthma since the early 1990s in an international cohort of young and middle-aged adults. A total of 28 centres from 14 countries participated in a longitudinal study. The study included 8,829 subjects with a mean follow-up time of 8.7 yrs. Change in the prevalence of use for medication was expressed as absolute net change (95% confidence interval) standardised to a 10-yr period. The use of anti-asthmatics was found to have increased by 3.1% (2.4-3.7%) and the prevalence of symptomatic asthma by 4.0% (3.5-4.5%). In the sample with asthma in both surveys (n=423), the use of inhaled corticosteroids increased by 12.2% (6.6-17.8%). Despite this, only 17.2% were using inhaled corticosteroids on a daily basis at follow-up. Females with continuous asthma were more likely, compared with males, and smokers with asthma, to have started using inhaled corticosteroids since the first survey. The use of anti-asthmatics has increased in a pattern consistent with current consensus on treatment. However, despite increased use of inhaled corticosteroids, a large majority of subjects with symptomatic asthma do not use this treatment on a daily basis, particularly males and smokers with asthma.

Psa Elevation during Intravesical Therapy for Superficial Bladder Carcinoma

PSA is commonly accepted as an indication for prostate biopsy. We determined PSA value in 81 consecutive patients treated with intravesical immuno- (59 cases) or chemotherapy (22 cases) for superficial bladder cancer. Blood samples were obtained before and after the induction course of instillation therapy and at 3, 6 and 12 months. We observed a clinical significant elevation of average PSA in 27 cases (45%) during BCG therapy and a return at the baseline levels within 12 months. Histological findings obtained in 10 patients shown inflammatory pictures in 9 cases. Prostate carcinoma was found only in one case with elevated PSA at 12 months. No significant differences of PSA levels were noted in patients treated with chemotherapy.

Our findings confirm that PSA increase in patients during intravesical BCG therapy is self-limited. Prostate biopsies in these patients are not mandatory and could be delayed while monitoring PSA.

Chronic cough and phlegm in young adults

The Global Initiative for Chronic Obstructive Lung Disease (GOLD) guidelines underline that the presence of chronic cough and sputum production before airflow obstruction offers a unique opportunity to identify subjects at risk of chronic obstructive pulmonary disease for an early intervention. Current epidemiological data on these subjects are scant. Between 1998-2000, the authors evaluated the prevalence and characteristics of these symptoms by a multicentre cross-sectional survey of Italian people aged between 20-44 yrs from the general population (Italian Study on Asthma in Young Adults (ISAYA)). Besides the questions on asthma, more than 18,000 subjects answered the question: "Have you had cough and phlegm on most days for as much as 3 months per year and for at least two successive years?" The adjusted prevalence of subjects with chronic cough and phlegm was 11.9%, being 11.8% in males and 12.0% in females. From these subjects approximately 20% reported coexisting asthma and approximately 30%, predominately females, were nonsmokers. The survey showed that sex (female), smoking and low socioeconomic status were significantly and independently associated with chronic cough and phlegm, current smoking playing the major role. The prevalence of subjects with chronic cough and phlegm is startlingly high among young adults. Further follow-up studies are needed to establish how many of them will go on to develop chronic obstructive pulmonary disease.

The impact of climate and traffic-related NO2 on the prevalence of asthma and allergic rhinitis in Italy

BACKGROUND

Environmental factors are likely to be involved in explaining the wide geographical variation in asthma and atopic diseases that has been documented in many recent epidemiological studies.

AIM

To evaluate to what extent climate and outdoor NO2 pollution can explain the geographical variation in the prevalence of asthma and allergic rhinitis, and to estimate the relative risk for exposure to different levels of these two factors.

METHODS

The impact of climate and long-term exposure to nitrogen dioxide (NO2) pollution on asthma and allergic rhinitis was assessed in a cross-sectional study, carried out during 1998 to 2000 on young adults aged 20 to 44 years (n = 18 873), living in 13 areas from two different Italian climatic regions (subcontinental and Mediterranean).

RESULTS

Mediterranean areas had a significantly higher prevalence of asthma-like symptoms (P < 0.001), higher annual mean temperature (16.2 degrees C vs. 12.9 degrees C), lower temperature range (16.0 C degrees vs. 22.1 degrees C) and lower NO2 levels (31.46 microg/m3 vs. 57.99 microg/m3) than subcontinental ones. Mediterranean climate was associated with an increased risk of wheeze (OR = 1.23; 95% CI 1.13 to 1.35), tightness in the chest (OR = 1.21; 95% CI 1.11 to 1.33), shortness of breath (OR = 1.21; 95% CI 1.08 to 1.36) and asthma attacks (OR = 1.19; 95% CI 1.07 to 1.31). After adjusting for climate, an increase of 18.3 microg/m3 in NO2 levels moderately increased the risk of asthma attacks (OR = 1.13; 95% CI 0.98 to 1.32), tightness in the chest (OR = 1.11; 95% CI 0.98 to 1.26) and wheeze (OR = 1.11; 95% CI 0.96 to 1.28). When the levels of outdoor NO2 exposure rose, the prevalence of allergic rhinitis increased significantly in the Mediterranean region (OR = 1.38; 95% CI 1.12 to 1.69), but not in the subcontinental one (OR = 1.03; 95% CI 0.83 to 1.28).

CONCLUSION

Our results show that the prevalence of asthma increases when annual mean temperature increases and temperature range decreases. Furthermore, climate interacts with NO2 outdoor exposure, increasing the risk for allergic rhinitis in people exposed to high stable temperatures. A long-term role for the effect of traffic pollution on asthma is also suggested.