Body mass index and the risk of asthma in adults

Self-reported prevalence of asthma and its associated factors among adult rural population in Bangladesh: a cross-sectional study using WHO PEN protocol

OBJECTIVE

For over a decade, the prevalence of asthma remained unchanged at around 7% in Bangladesh. Although asthma causes significant morbidity among both children and adults, updates on epidemiological data are limited on the prevalence in Bangladesh. This study attempted to determine the prevalence of asthma, and its modifiable and non-modifiable lifestyle predictors in a rural population of Bangladesh.

METHOD

This study was part of a cross-sectional study that applied the WHO Package of Essential Noncommunicable Disease Interventions via census in a rural area of Bangladesh, where self-reported data on asthma were recorded. Data on anthropometric measurement, sociodemographic characteristics and behavioural risk factors were collected following the standard protocol described in the WHO STEP-wise approach to surveillance (STEPS) questionnaire. Analysis included descriptive statistics to assess the prevalence of asthma and its risk factors, and binary logistic regression to determine contributing factors.

RESULT

The overall prevalence of asthma was 4.2%. Asthma was predominant among people above 60 years (8.4%). Higher asthma was noted among males (4.6%), self-employed (5.1%), with a family history of asthma (9.1%), with comorbidities besides asthma (7.8%) and underweight (6.0%) compared with their counterparts. The OR of having asthma was 1.89, 1.93, 1.32, 1.50, 2.60, 0.67, 0.67 and 0.78 if a respondent was 45 years old or more, married, underweight, ever smoker, with a family history of asthma, housewife, employed and consumed red meat, respectively, while considering all other variables constant, compared with their counterparts.

CONCLUSION

The study emphasised asthma to be a public health concern in Bangladesh, although it seems to have decreased over the last decade. Among others, red meat intake and nutritional status were strongly associated with asthma, and the linkage among these is still a grey area that needs further exploration.

Asthma exacerbations and body mass index in children and adolescents: experience from a tertiary care center

The prevalence and incidence of asthma continue to rise globally. Obesity has been identified as a potential risk factor for asthma exacerbations. The association between body mass index (BMI) and asthma is not well studied in some regions. This study aims to investigate the impact of BMI on pediatric asthmatic patients. This retrospective study was conducted at the Aga Khan University Hospital from 2019 to 2022. Children and adolescents with asthma exacerbations were included. The patients were classified into four groups based on their BMI: underweight, healthy weight, overweight, and obese. The demographic characteristics, medications used, predicted forced expiratory volume in 1 second (FEV1) measurements, asthma exacerbations per year, length of stay per admission, and the number of patients requiring high dependency unit (HDU) care were recorded and analyzed. Our results demonstrated that patients in the healthy weight category had the highest percentage of FEV1 (91.46±8.58) and FEV1/forced vital capacity (FVC) (85.75±9.23) (p<0.001). The study found a significant difference in the average number of asthma exacerbations per year between the four groups. Obese patients had the highest number of episodes (3.22±0.94), followed by the underweight group (2.42±0.59) (p<0.01). The length of stay per admission was significantly shorter for patients with a healthy weight (2.0±0.81), and there was a statistically significant difference observed in the number of patients requiring HDU care among the four groups, as well as in the average length of stay at the HDU (p<0.001). Elevated BMI is related to an increased number of annual asthma exacerbations, a low FEV1 and FEV1/FVC, an increased length of stay at admission, and an increased stay in the HDU.

The obstetric aspects of maternal asthma

Asthma is the commonest chronic medical condition encountered in pregnancy. Poor asthma control and exacerbations are frequently encountered due to treatment non-adherence, pregnancy-related aggravating factors such as increased susceptibility to viral infections, and comorbidities that are commonly associated. Asthma-related inflammatory reactions and placental effects, the effect of medications, and respiratory symptoms and hypoxia are probably to interact to result in an increased adverse obstetric outcomes including miscarriage, foetal congenital anomalies, pregnancy hypertensive disorders, gestational diabetes, preterm labour and birth, antepartum haemorrhage, low birthweight and foetal growth restriction (FGR), caesarean delivery, postpartum haemorrhage (PPH), maternal intensive care admission, and even mortality, while the offspring also has increased long-term morbidity. Interdisciplinary management with frequent assessment by symptoms, spirometry, and biomarkers, together with removal of risk factors such as smoking and appropriate instigation of treatment including short courses of systemic corticosteroid, could ensure optimal and tailored treatment to control symptoms, prevent exacerbations, and ultimately enhancing maternal and perinatal outcomes.

Sex Differences in Airway Remodeling and Inflammation: Clinical and Biological Factors

Asthma is characterized by an increase in the contraction and inflammation of airway muscles, resulting in airflow obstruction. The prevalence of asthma is lower in females than in males until the start of puberty, and higher in adult women than men. This sex disparity and switch at the onset of puberty has been an object of debate among many researchers. Hence, in this review, we have summarized these observations to pinpoint areas needing more research work and to provide better sex-specific diagnosis and management of asthma. While some researchers have attributed it to the anatomical and physiological differences in the male and female respiratory systems, the influences of hormonal interplay after puberty have also been stressed. Other hormones such as leptin have been linked to the sex differences in asthma in both obese and non-obese patients. Recently, many scientists have also demonstrated the influence of the sex-specific genomic framework as a key player, and others have linked it to environmental, social lifestyle, and occupational exposures. The majority of studies concluded that adult men are less susceptible to developing asthma than women and that women display more severe forms of the disease. Therefore, the understanding of the roles played by sex- and gender-specific factors, and the biological mechanisms involved will help develop novel and more accurate diagnostic and therapeutic plans for sex-specific asthma management.

A nationwide survey of the association between nonalcoholic fatty liver disease and the incidence of asthma in Korean adults

Background

Asthma and nonalcoholic fatty liver disease (NAFLD) are chronic diseases known to be associated with metabolic abnormalities. We aimed to clarify the association between NAFLD and asthma incidence in a large population-based cohort.

Methods and findings

We selected 160,603 individuals without comorbidities from the National Health Insurance Service-National Sample cohort between 2009 and 2014. NAFLD was defined using a surrogate marker, fatty liver index (FLI). During a median of 5.08 years’ follow-up, 16,377 subjects (10.2%) were newly diagnosed with asthma and categorized into three groups according to FLI. The cumulative incidence of asthma was higher in subjects with higher vs. lower FLIs (FLI < 30, 10.1%; 30 ≤ FLI < 60, 10.8%; FLI ≥ 60, 10.5%). Higher FLI was associated with an increased incidence of asthma (Hazard ratios (HR)_{highest vs. lowest FLI}, 1.25; 95% CI, 1.15–1.36). The results using another definition of NAFLD, as measured by the hepatic steatosis index (HSI), were similar to the primary results. This association was more pronounced in women than in men (HR 1.46; 95% CI, 1.13–1.64 vs. HR 1.07; 95% CI, 0.94–1.20).

Conclusions

This study demonstrated that NAFLD, as measured by FLI and HSI, may influence the incidence rates of asthma in adults, especially in women.

Elevated Serum Leptin Levels in Patients With Eosinophilic Chronic Rhinosinusitis

Background: Eosinophilic chronic sinusitis (ECRS) is a subtype of CRS with nasal polyps (CRSwNP) that is frequently comorbid with asthma. Notably, ECRS patients often show a high recurrence of NPs after surgical resection. Leptin is a hormone produced by adipocytes that has been implicated in airway inflammatory diseases. However, to date, the role of leptin in ECRS has not been investigated. Objective: To determine whether the serum levels of leptin are altered in patients with ECRS. Methods: In total, 40 patients with ECRS, 15 patients with non-eosinophilic CRS (non-ECRS), and 12 individuals without CRS (control) were included in this study. Patient's serum leptin levels were assessed, and the number of eosinophils in their NPs were measured through a histological evaluation of the three densest areas with cellular infiltrate beneath the epithelial surface. Finally, nasal fibroblast cultures established from NPs were stimulated with varying concentrations of recombinant leptin in vitro to determine whether leptin affects eotaxin-3 (Chemokine (C-C motif) ligand 26 :26: CCL26) expression. Results: The serum leptin levels in both the ECRS and non-ECRS groups were significantly higher than those in the control subjects (p < 0.0001 vs. ECRS; p < 0.05 vs. non-ECRS). Furthermore, ECRS patients displayed significantly elevated serum leptin levels compared to non-ECRS patients (p < 0.001), although there was no difference in body mass index between the groups. Notably, serum leptin levels were correlated with the proportion of eosinophils in peripheral blood (r = 0.3575, p < 0.01) and the number of eosinophils in NPs (r = 0.5109, p < 0.0001). Serum leptin levels were also correlated with eotaxin-3 mRNA expression in NPs (r = 0.5374, p < 0.01). Finally, leptin significantly augmented eotaxin-3 expression in nasal fibroblasts established in vitro from NPs in a leptin receptor-dependent manner (p < 0.05). Conclusion: Leptin levels are elevated in ECRS patients and may both promote and indicate the severity of ECRS as well as systemic type 2-biased inflammatory responses. Combined, these data indicate that circulating leptin may play a significant role in the development of eosinophilic inflammation in NPs.

Obesity as a Condition Determined by Food Addiction: Should Brain Endocannabinoid System Alterations Be the Cause and Its Modulation the Solution?

Obesity is a complex disorder, and the number of people affected is growing every day. In recent years, research has confirmed the hypothesis that food addiction is a determining factor in obesity. Food addiction is a behavioral disorder characterized by disruptions in the reward system in response to hedonic eating. The endocannabinoid system (ECS) plays an important role in the central and peripheral control of food intake and reward-related behaviors. Moreover, both obesity and food addiction have been linked to impairments in the ECS function in various brain regions integrating peripheral metabolic signals and modulating appetite. For these reasons, targeting the ECS could be a valid pharmacological therapy for these pathologies. However, targeting the cannabinoid receptors with inverse agonists failed when used in clinical contexts as a consequence of the induction of affective disorders. In this context, new classes of drugs acting either on CB1 and/or CB2 receptors or on synthetic and degradation enzymes of endogenous cannabinoids are being studied. However, further investigation is necessary to find safe and effective treatments that can exert anti-obesity effects, normalizing reward-related behaviors without causing important adverse mood effects.

Association between prevalence of obstructive lung disease and obesity: results from The Vermont Diabetes Information System

BACKGROUND

The association of obesity with the development of obstructive lung disease, namely asthma and/or chronic obstructive pulmonary disease, has been found to be significant in general population studies, and weight loss in the obese has proven beneficial in disease control. Obese patients seem to present with a specific obstructive lung disease phenotype including a reduced response to corticosteroids. Obesity is increasingly recognized as an important factor to document in obstructive lung disease patients and a critical comorbidity to report in diabetic patients, as it may influence disease management. This report presents data that contributes to establishing the relationship between obstructive lung disease in a diabetic cohort, a population highly susceptible to obesity.

METHODS

A total of 1003 subjects in community practice settings were interviewed at home at the time of enrolment into the Vermont Diabetes Information System, a clinical decision support program. Patients self-reported their personal and clinical characteristics, including any history of obstructive lung disease. Laboratory data were obtained directly from the clinical laboratory, and current medications were obtained by direct observation of medication containers. We performed a cross-sectional analysis of the interviewed subjects to assess a possible association between obstructive lung disease history and obesity.

RESULTS

In a multivariate logistic regression model, a history of obstructive lung disease was significantly associated with obesity (body mass index ≥30) even after correcting for potential confounders including gender, low income (<$30,000/year), number of comorbidities, number of prescription medications, cigarette smoking, and alcohol problems (adjusted odds ratio (OR) = 1.58, P = 0.03, 95% confidence interval (CI) = 1.05, 2.37). This association was particularly strong and significant among female patients (OR = 2.18, P = < 0.01, CI = 1.27, 3.72) but not in male patients (OR = 0.97, P = 0.93, CI = 0.51, 1.83).

CONCLUSION

These data suggest an association between obesity and obstructive lung disease prevalence in patients with diabetes, with women exhibiting a stronger association. Future studies are needed to identify the mechanism by which women disproportionately develop obstructive lung disease in this population.

Screening for Anxiety Disorders Among Schoolchildren with Asthma

The aim of this study was to perform screening for anxiety disorders among children with asthma and to reveal factors associated with general anxiety disorder and its specific forms.

This was a cross-sectional study conducted among out-patients with asthma during routine visits to pediatricians. They were screened for anxiety disorders using SCARED self-reported questionnaire. Additional data were collected using specially designed questionnaire as well as the patient files. Statistical analysis was performed by the SPPS software using descriptive statistics and logistic regression.

Study population consisted mostly of schoolchildren (n=58), 8-12 years old, and adolescents (13-17 years) (n=13). Approximately 33.8% respondents were positive for general anxiety disorder. The most common were separation anxiety and social anxiety, recorded among 49.3% and 32.4% of patients, respectively. Generalized anxiety and panic/somatic disorder were recorded in the same percentage of patients (21.3%), while avoiding school was the least frequent (14.08%). Influence of numerous factors was tested, but only the following showed significant effects: peak expiratory flow test was associated with general anxiety disorder, patient’s age and gender with PD, and living place, asthma control according to GINA and age on GAD. Parent’s smoking was associated with SAD, age and patient’s weight status with SPH, and GINA asthma control with SA.

These findings suggest that anxiety disorders are common among children and adolescents with asthma. Various factors can be associated with general anxiety disorder and its specific forms, but some of them being preventable as avoiding smoking in the family.

Evaluation of Interleukin-6, Leukotriene B-4, and Nitric Oxide Levels in Exhaled Breath Condensate of Asymptomatic Obese Individuals: Are Obese Patients Under Risk of Developing Asthma?

Objective

If systemic inflammation in relation with obesity causes asthma, the detection of increased airway inflammation among obese individuals who do not have any respiratory symptoms can be also beneficial in indentifying obese patients who are at risk of developing asthma. The aim of this study was to evaluate the systemic and airway inflammation of asymptomatic obese and non-obese individuals.

Materials and Methods

Obese and non-obese individuals with no respiratory symptoms were included. Inflammatory biomarkers such as C-reactive protein (CRP), exhaled breath condensate (EBC) interleukin-6 (IL-6), EBC leukotriene B-4 (LTB-4), and EBC nitric oxide (NO) levels of obese and non-obese individuals were determined.

Results

Forty-five obese individuals (body mass index [BMI]≥30) and 31 non-obese individuals (BMI≤25) as a control group were included in this study. The mean age of the obese group (38.7±11.4 years) was significantly higher than the one of the non-obese group (29.5±8.6 years; p<0.001). There was no significant relationship between gender and BMI (χ² =1.471, p=0.225). CRP levels were significantly higher in the obese group (6.94±8.28) than the non-obese group (3.29±0.39; p<0.001). The levels of EBC IL-6 in obese and non-obese group were found as 22.61±12.53 and 21.08±14.39, respectively (p=0.624). There was no significant difference between EBC NO levels of the obese group and non-obese group (24.35±10.9 vs. 21.56±7.83; p=0.226). No significant difference was found between the EBC LTB-4 level in the obese group and the non-obese group (36.39±89.82 vs. 16.64±17.45; p=0.231).

Conclusion

Increased systemic inflammation in obese individuals who had no respiratory symptoms might indicate the tendency of asthma. However, airway inflammation was not significantly different between groups. Therefore the relationship between obesity and asthma should be investigated in future large-scale studies determining the direct effects of adipokines on airways.

Obesity and childhood asthma

PURPOSE OF REVIEW

Asthma is a common chronic disease of the airways characterized by recurrent respiratory symptoms, bronchoreactivity, and airway inflammation. The high toll on quality of life has led to sustained efforts to understand the factors leading to asthma inception and poor disease control. Obesity is another increasingly common pediatric disease, which appears to increase the risk for incident asthma and worsened disease severity. Currently, our understanding of how obesity affects asthma risk and affects its phenotypic characteristics remains incomplete. The current review describes our current understanding of the epidemiology, clinical characteristics, and management considerations of obesity-related asthma in children.

RECENT FINDINGS

The epidemiologic relationship between obesity in children and incident asthma remains confusing despite numerous longitudinal cohort studies, and appears to be influenced by early life exposures, patterns of somatic growth and underlying familial risks of allergic disease. Children with comorbid obesity and asthma demonstrate diverse phenotypic characteristics which are still becoming clear.

SUMMARY

Like any child with asthma, a child with comorbid obesity requires an individualized approach adhering to current best-practice guidelines and an understanding of how obesity and asthma may interact.

Association between Body Mass Index and Prevalence of Asthma in Korean Adults

We evaluated the association between body mass index (BMI) and the prevalence of asthma. Using data from the 2015 Korean Community Health Survey, 214,971 participants aged between 19 and 106 years were included in this study. Asthma was defined based on the self-report of physician diagnosis. BMI was classified as underweight (<18.5 kg/m²), normal weight (18.5 kg/m²≤BMI<23.0 kg/m²), overweight (23.0 kg/m²≤ BMI<27.4 kg/m²), and obese (≥27.5 kg/m²) based on the BMI categories for Asians by the World Health Organization. Multiple logistic regression analysis was performed with sampling weights to evaluate the association between BMI and asthma after adjusting for age, educational level, income, type of residential area, smoking status, alcohol consumption, physical activity, hypertension, and diabetes. In men, BMI had an inverted J-shaped association with the prevalence of asthma, with an odds ratio of 1.88 (95% confidence interval [CI]: 1.89-2.24) for underweight and 1.12 (95% CIs: 0.97-1.29) for obesity. In women, BMI had a J-shaped association with the prevalence of asthma, with an odds ratio of 1.05 (95% CIs: 0.91-1.22) for underweight and 2.29 (95% CIs: 2.06-2.56) for obesity. In conclusion, in a nationally representative sample of Korean adults, the association between BMI and the prevalence of asthma varied between the sexes. This suggests that malnutrition and obesity are involved in the pathophysiology of asthma.

Prevalence and impact of risk factors for poor asthma outcomes in a large, specialist-managed patient cohort: a real-life study

Background

Risk factors for poor asthma outcomes may have considerable influence on the control level and medical care of asthmatic patients. Our objective was to conduct a study that provides data on the level of symptom control and the frequency of specific risk factors for poor asthma outcomes on a large patient cohort.

Methods

A cross-sectional, non-interventional real-life study was conducted among asthmatic patients treated by respiratory specialists in Hungary. Asthma control and risk factor assessment were done according to Global Initiative for Asthma guideline (Box 2–2). In the data analysis, phase descriptive statistics, graphical outputs, and Fisher’s exact tests were used.

Results

Of 12743 patients enrolled by 187 specialists, asthma was well controlled in 36.0%, partially controlled in 29.29%, and uncontrolled in 34.71% of the cases. The most common comorbidities were rhinitis/sinusitis (66.84%), cardiovascular diseases (43.81%), and gastroesophageal reflux disease (20.11%). The following risk factors had the strongest relationship with uncontrolled disease: incorrect inhaler technique causing side effects (odds ratio, OR 4.86, 3.51–6.8), previous severe exacerbation (OR 4.79, 4.02–5.72), high short-acting beta agonist (SABA) use (OR 4.46, 4.03–4.93), incorrect inhaler technique associated with an exacerbation (OR 3.91, 3.06–5.03), and persistently low forced expiratory volume in 1 s (FEV₁, OR 3.14, 2.8–3.52). The most frequent risk factors were smoking (OR 1.47, 1.36–1.59) and obesity (OR 1.34, 1.24–1.45). Furthermore, high loss of control was associated with an initial low FEV₁ (OR 2.21, 2.01–2.44), frequent oral corticosteroid (OCS) use (OR 1.83, 1.64–2.05), poor adherence to treatment (OR 2.51, 2.21–2.86), and allergen exposure (OR 1.63, 1.47–1.81).

Conclusions

This study indicated that the presence of risk factors for poor asthma outcomes listed by the Global Initiative for Asthma document significantly influenced actual control level in a real-world large patient cohort, with high SABA use, previous severe exacerbation, incorrect inhaler technique, persistently low FEV₁, and poor adherence to treatment having the highest impact.

Type 2 Diabetes and Asthma: Systematic Review of the Bidirectional Relationship

BACKGROUND AND OBJECTIVE

Obesity is an important contributor to the risk of both asthma and Type 2 Diabetes (T2DM). However, it has been suggested that T2DM and asthma are also independently associated. The aim of this systematic review was to synthesize the evidence for an independent relationship between T2DM and asthma.

METHODS

MEDLINE and EMBASE were searched for studies reporting the relationship between asthma and T2DM in adults. Given a potential bidirectional relationship, articles relating to T2DM as a risk factor for asthma, and asthma as a risk factor for T2DM were examined separately.

RESULTS

Eight studies were identified for inclusion in the review (n=2,934,399 participants). Four studies examined incident diabetes in those with asthma. The pooled (random effects model) adjusted hazard ratio for incident T2DM in asthma was 1.37 (95%CI 1.12-1.69; p <0.001) after controlling for BMI. Four studies reported prevalence or incidence rates of asthma in people with T2DM; higher rates of asthma in those with T2DM were reported in all four studies. Meta-analysis of results was not possible due to methodological heterogeneity. The quality of included studies was good, but due to small numbers, publication bias cannot be excluded.

CONCLUSION

The published literature suggests a bidirectional independent relationship between T2DM and asthma, although we cannot exclude publication bias.

A review of obesity and asthma across the life span

OBJECTIVE

This literature review aims to compare obese-asthmatic adults and children, and to characterize differences and similarities between the two subgroups from epidemiological, demographical, phenotypical, and physiological perspectives.

METHODS

Literature search was conducted using Pubmed database with "obesity," "asthma," "epidemiology," "cluster analysis," "demography," "mechanics," and ''FeNO'' as search terms.

METHODS

Articles investigating epidemiological, demographic, phenotypical variation, and mechanical aspects of breathing specifically in obese asthmatics were identified. The studies were then divided according to age: children (<18 years of age) and adults (>18 years of age).

RESULTS

Increase in asthma incidence and prevalence is observed in both obese-asthmatic children and adults. Asthma prevalence is greater in adult females regardless of ethnic background, and in men of African American and Hispanic ethnicities. Degree of weight gain and early onset of menarche appears to directly affect asthma severity in adolescent girls and females. Airway hyperresponsiveness and fractional exhaled nitric oxide do not have any positive correlation with high BMI in obese-asthmatic children and adults. Obesity also alters lung mechanics in asthmatics, but the impact is different for children and adults likely due to differential effect of obesity on central and peripheral airway.

CONCLUSION

Existing literature suggests both similarities and differences in obese-asthmatic children and adults. The most pertinent differences are related to gender, ethnicity, and lung functions.

Asthma in the elderly and late-onset adult asthma

Elderly asthmatics are at a higher risk for morbidity and mortality from their asthma than younger patients. There are important age-related physiologic and immunologic changes that complicate the presentation, diagnosis, and management of asthma in the aged population. Evidence suggests that elderly asthmatics are more likely to be underdiagnosed and undertreated. Additionally, elderly patients with asthma have highest rates of morbidity and mortality from their disease than younger patients. The underlying airway inflammation of asthma in this age group likely differs from younger patients and is felt to be non-type 2 mediated. While elderly patients are underrepresented in clinical trials, subgroup analysis of large clinical trials suggests they may be less likely to respond to traditional asthma therapies (ie, corticosteroids). As the armamentarium of pharmacologic asthma therapies expands, it will be critical to include elderly asthmatics in large clinical trials so that therapy may be better tailored to this at-risk and growing population.

Prevalence and associated factors for self-reported asthma in a Canadian population: The Canadian Community Health Survey, 2014

BACKGROUND

Asthma prevalence is increasing among adults, yet limited information regarding the association between adult asthma and environmental and personal exposures is available using large nationally representative population-based survey.

OBJECTIVE

To determine the prevalence of asthma and associated factors for self-reported asthma in a Canadian population aged 12 years and older by using the Canadian Community Health Survey (CCHS) 2014 cross-sectional cohort.

METHODS

We used data from the 2014 CCHS. Asthma was determined through self-reported health professional diagnosis. Information regarding covariates of importance, such as socio-economic status, life style variables, was obtained. A weighted logistic regression analysis was performed with appropriate technique for clustering effects.

RESULTS

Estimated self-reported asthma prevalence of 8.1% in the greater than 12 years old Canadian population was observed. We found that a substantial proportion of Canadians (aged 12 and older) reported having asthma and geographical differences and differences between specific provinces in asthma prevalence. Women had higher prevalence of asthma than men, but the relationship depended on age and body mass index (BMI). Interactions between household income and smoking status were observed to predict the probability of asthma.

CONCLUSIONS

Additional studies are needed to determine which factors influence the asthma prevalence between sex, BMI as well as smoking status and household income and its interactions with each other.

Obesity, Oxidative Stress, Adipose Tissue Dysfunction, and the Associated Health Risks: Causes and Therapeutic Strategies

Obesity is gaining acceptance as a serious primary health burden that impairs the quality of life because of its associated complications, including diabetes, cardiovascular diseases, cancer, asthma, sleep disorders, hepatic dysfunction, renal dysfunction, and infertility. It is a complex metabolic disorder with a multifactorial origin. Growing evidence suggests that oxidative stress plays a role as the critical factor linking obesity with its associated complications. Obesity per se can induce systemic oxidative stress through various biochemical mechanisms, such as superoxide generation from NADPH oxidases, oxidative phosphorylation, glyceraldehyde auto-oxidation, protein kinase C activation, and polyol and hexosamine pathways. Other factors that also contribute to oxidative stress in obesity include hyperleptinemia, low antioxidant defense, chronic inflammation, and postprandial reactive oxygen species generation. In addition, recent studies suggest that adipose tissue plays a critical role in regulating the pathophysiological mechanisms of obesity and its related co-morbidities. To establish an adequate platform for the prevention of obesity and its associated health risks, understanding the factors that contribute to the cause of obesity is necessary. The most current list of obesity determinants includes genetic factors, dietary intake, physical activity, environmental and socioeconomic factors, eating disorders, and societal influences. On the basis of the currently identified predominant determinants of obesity, a broad range of strategies have been recommended to reduce the prevalence of obesity, such as regular physical activity, ad libitum food intake limiting to certain micronutrients, increased dietary intake of fruits and vegetables, and meal replacements. This review aims to highlight recent findings regarding the role of oxidative stress in the pathogenesis of obesity and its associated risk factors, the role of dysfunctional adipose tissue in development of these risk factors, and potential strategies to regulate body weight loss/gain for better health benefits.

Association between obesity and asthma - epidemiology, pathophysiology and clinical profile

Obesity is a risk factor for asthma, and obese asthmatics have lower disease control and increased symptom severity. Several putative links have been proposed, including genetics, mechanical restriction of the chest and the intake of corticosteroids. The most consistent evidence, however, comes from studies of cytokines produced by the adipose tissue called adipokines. Adipokine imbalance is associated with both proinflammatory status and asthma. Although reverse causation has been proposed, it is now acknowledged that obesity precedes asthma symptoms. Nevertheless, prenatal origins of both conditions complicate the search for causality. There is a confirmed role of neuro-immune cross-talk mediating obesity-induced asthma, with leptin playing a key role in these processes. Obesity-induced asthma is now considered a distinct asthma phenotype. In fact, it is one of the most important determinants of asthma phenotypes. Two main subphenotypes have been distinguished. The first phenotype, which affects adult women, is characterised by later onset and is more likely to be non-atopic. The childhood obesity-induced asthma phenotype is characterised by primary and predominantly atopic asthma. In obesity-induced asthma, the immune responses are shifted towards T helper (Th) 1 polarisation rather than the typical atopic Th2 immunological profile. Moreover, obese asthmatics might respond differently to environmental triggers. The high cost of treatment of obesity-related asthma, and the burden it causes for the patients and their families call for urgent intervention. Phenotype-specific approaches seem to be crucial for the success of prevention and treatment.

Different risk factor patterns for adult asthma, rhinitis and eczema: results from West Sweden Asthma Study

BACKGROUND

Atopic diseases including asthma, rhinitis and eczema have increased in the second half of the past century. This has been well studied among children and adolescents but with the exception of asthma to a much lesser extent in adults. The adult risk factor pattern of atopic diseases, in particular of eczema, and their relation to allergic sensitization are yet to be fully elucidated. Studies among adults that have compared the risk factor pattern for these conditions in the same material are very few. The objective of this study was to compare the risk factor patterns for asthma, rhinitis and eczema in a randomly selected adult population.

METHODS

A questionnaire survey on atopic diseases was dispatched by mail to 30,000 randomly selected individuals in West Sweden aged 16-75 years and 62 % participated. A subgroup of 2000 individuals was selected for clinical examinations including blood sampling for specific serum Immunoglobulin E to common airborne allergens and 1172 attended.

RESULTS

The prevalence of current asthma was 11.8 %, current rhinitis 42.8 %, current eczema 13.5 and 2.3 % had all three conditions while 13.9 % had at least two conditions. No mutual risk factor was identified for all three conditions. Allergic sensitization was a strong risk factor for current asthma (OR 4.1 CI 2.7-6.3) and current rhinitis (OR 5.1 CI 3.8-6.9) but not so for current eczema. Obesity was a risk factor for current asthma and current rhinitis, while farm childhood decreased the risk for current asthma and current rhinitis. Occupational exposure to gas dust or fumes and female sex was associated with an increased risk of current asthma and current eczema.

CONCLUSIONS

There are different risk factor patterns for asthma, rhinitis and eczema in adults but some risk factors are overlapping between some of the conditions. The effect of mutable risk factors should be assessed further in longitudinal studies.

Is obesity a predisposing factor for free flap failure and complications? Comparison between breast and nonbreast reconstruction: Systematic review and meta-analysis

Obesity is a risk factor for postoperative morbidity in breast reconstruction. Although existing studies about nonbreast reconstruction are limited, previous research has demonstrated that obesity is not an important factor in poor outcomes in nonbreast reconstruction. Our study evaluates the effects of obesity on postoperative morbidity in nonbreast reconstruction in comparison to breast reconstruction. A systematic literature review and meta-analysis was performed using Medline, EMBASE, and Cochrane databases. Obesity was extracted for predictor variables and partial, total loss of flap, and complication were extracted for outcome variables. Subgroup analyses were performed according to reconstruction site. The Newcastle-Ottawa scale (NOS) was used to assess the quality of the studies, and the Cochrane risk of bias tool was used. Publication bias was evaluated using funnel plots. The search strategy identified 944 publications. After screening, 19 articles were selected for review. Partial flap loss, total flap loss, and complications in breast reconstruction occurred significantly more often in obese patients in comparison to nonobese patients (OR = 2.479, P = 0.021 for partial loss, OR = 3.083, P = 0.002 for total loss, OR = 2.666, P = 0.001 for complications). In contrast, partial flap loss, total flap loss, and complications in nonbreast reconstruction were not significantly different in obese patients in comparison to nonobese patients (OR = 0.786, P = 0.629 for partial loss, OR = 0.960, P = 0.961 for total loss, and OR = 1.009, P = 0.536 for complications). In contrast to the relationship between obesity and poor outcomes in breast reconstruction, our study suggests the obesity is not a predisposing factor for poor outcomes in nonbreast reconstruction. Long-term studies are needed to confirm these findings.

Bronchospasm in obese patients undergoing elective laparoscopic surgery under general anesthesia

Background

Existing data suggest that obesity correlates with airway hyper-reactivity. However, the incidence of bronchospasm during bariatric surgery in obese patients has not been well studied.

Methods

This was a prospective observational study comparing 50 obese versus 50 non obese patients undergoing elective laparoscopic surgery over a 2 year period. Bronchospasm was detected clinically by auscultation and was confirmed by measuring peak airway pressure during mechanical ventilation. Blood gases were measured at predetermined time intervals intraoperatively. Categorical variables were analyzed using Fisher’s exact test, while numerical variables within and between groups were compared using repeated measures general linear model.

Results

The incidence of bronchospasm was significantly higher in obese compared to non obese patients (P = 0.027). Peak airway pressures and blood gases differed significantly when comparing non obese patients versus obese patients without bronchospasm versus obese patients with bronchospasm. Hypoventilation resulting in gradual increase of arterial PaCO₂ was noted in all groups during surgery.

Conclusion

The incidence of bronchospasm is higher in obese patients compared to non obese patients undergoing elective laparoscopic surgery. Airway pressures and blood gas values in obese patients are somewhere between values in non obese patients and values in patients with bronchospasm, thereby implying that obesity is associated with a state where bronchial smooth muscles are not fully relaxed. Consideration of increased airway reactivity in obese patients undergoing laparoscopic surgery is important for improved patient care and uneventful anesthetic course.

A new childhood asthma phenotype: obese with early menarche

Three concomitant phenomena occur in the later years of childhood: increases in the incidence of asthma, obesity and early menarche. This article is an overview of the current epidemiologic, basic, genetic and epigenetic evidence about this relationship. As a consequence we propose that obese girls who have an early menarche (≤ 11 years of age) constitute a new asthma phenotype in childhood. Future studies need to be carried out in order to find the best control and treatment of this new asthma phenotype.

Adolescent Student Use of School-Based Salad Bars

BACKGROUND

Childhood obesity continues to be a public health problem in the United States. Increasing consumption of fruits and vegetables (F/V) is one strategy for decreasing high consumption of energy-dense, high-fat foods, thereby improving weight status. Many Orleans Parish public schools were provided with salad bars (SBs) to augment school lunch with increased access to F/V. This study identified factors associated with student use of SBs.

METHODS

Surveys examining SB use, demographics, food preference, nutrition knowledge, and social support were administered to students in the 7th to 12th grades (N = 702) in Orleans Parish (New Orleans, Louisiana). Generalized estimating equations, which incorporate clustering at the school level, helped to determine associations between independent variables and SB use.

RESULTS

Sixty percent of participants were SB users. Non-African-American students were more likely to be SB users than African-American students (odds ratio [OR] = 2.35, confidence interval [CI]: 1.35-4.07) and students who had high preference for healthy food were more likely to use the SB than those who had low preference (OR = 2.41, CI: 1.44-4.01). Students who encouraged others to consume F/V were more likely to use the SB than those who did not (p = .015).

CONCLUSIONS

Individual and interpersonal factors related to SB use can provide guidance in the development of school-based interventions to increase SB use and F/V consumption.

Sex difference in the association between obesity and asthma in U.S. adults: Findings from a national study

BACKGROUND

Obesity and asthma are both prevalent in the U.S. The a few studies that have examined the differences in association between obesity and asthma by sex provided mixed results. Reason for the sex differences is not well understood.

OBJECTIVE

Using U.S. nationally representative data we aimed to examine the association between obesity and asthma and potential sex differences.

METHODS

Data were obtained from the 2012 National Health Interview Survey (n = 33,153 adults, 4197 had asthma). Asthma was determined by a positive response to the question "Has a doctor or health care professional ever told you had asthma?" Obesity was determined as a Body Mass Index (BMI)≥30. Obese status was categorized as BMI = 30-34.9 (Class I obesity), BMI = 35-39.9 (Class II obesity), and BMI≥40 (Class III obesity).

RESULTS

The prevalence of asthma was 12.6% (11.0% in men, 14.2% in women), and was higher in the obese than non-obese individuals (16.6% vs. 11.1%, p < 0.0001). After controlling for potential confounders, Class I obesity (OR = 1.27, 95% CI = 1.11-1.44), Class II obesity (OR = 1.55, 95% CI = 1.31-1.84), Class III obesity (OR = 1.85, 95% CI = 1.54-2.21) were positively associated with asthma. The association between Class III obesity and asthma was stronger in women than men (2.11 (1.70-2.63) vs. 1.40 (1.01-1.96), p < 0.05), although the sex difference in the association between BMI and asthma was not significant. Positive associations between class II and class III obesity and asthma were observed among young and middle-aged women compared to young and middle-aged men. Stratified by allergic status, obesity remained being positively associated with asthma.

CONCLUSION

The prevalence of asthma was higher in women than men. Obesity (and BMI) was positively associated with asthma, overall or stratified by allergic status. The association between Class III obesity and asthma was stronger in women. Obesity and sex may be taken into consideration for the management of asthmatic patients.

Changes in prevalence of chronic obstructive pulmonary disease and asthma in the US population and associated risk factors

Chronic lower airway diseases, including chronic obstructive pulmonary disease (COPD) and asthma, are currently the third leading cause of death in the United States. We aimed to evaluate changes in prevalence of and risk factors for COPD and asthma among the US adult population. We evaluated changes in prevalence of self-reported doctor-diagnosed COPD (i.e. chronic bronchitis and emphysema) and asthma and self-reported respiratory symptoms comparing data from the 1988-1994 and 2007-2010 National Health and Nutrition Examination Surveys. To investigate changes in the severity of each outcome over the two periods, we calculated changes in the proportions of spirometry-based airflow obstruction for each outcome. Prevalence of doctor-diagnosed chronic bronchitis and emphysema decreased significantly mainly among males, while asthma increased only among females. The self-reported disease and the respiratory symptoms were associated with increased prevalence of airflow obstruction for both periods. However, the prevalence of airflow obstruction decreased significantly in the second period among those with shortness of breath and doctor-diagnosed respiratory conditions (chronic bronchitis, emphysema, and asthma). COPD outcomes and asthma were associated with lower education, smoking, underweight and obesity, and occupational dusts and fumes exposure. Chronic lower airway diseases continue to be major public health problems. However, decreased prevalence of doctor-diagnosed chronic bronchitis and emphysema (in males) and decreased prevalence of airflow obstruction in those with respiratory symptoms and doctor-diagnosed respiratory diseases may indicate a declining trend and decrease in disease severity between the two periods. Continued focus on prevention of these diseases through public health interventions is prudent.

Gender Associated High Body Mass Index in Allergic Diseases

BACKGROUND:

The increasing prevalence of allergic diseases and atopy is affected by sex, age and lifestyle factors. Obesity and excess weight are reported to be potential risk factors for atopy and specifically for asthma symptoms in children and adults.

OBJECTIVE:

To assess the relation between body mass index (BMI) and allergic diseases in patients of both genders, as well as association of BMI with atopy in healthy subjects.

METHODS:

BMI (kg/m²), skin-prick test and total serum immunoglobulin E levels were assessed in 139 subjects: 109 were patients with allergic diseases (M to F ratio was 51:58) and 30 were healthy controls (M to F ratio was 6:24).

RESULTS:

The study population was grouped into asthma, asthmarhinitis, rhinitis, Urticaria oreczema and controls by BMI and sex. Females with the highest BMI were in asthma and urticaria/eczema group. Males with the highest BMI were in asthmarhinitis and urticariaeczema group. High BMI was associated with atopy in both genders of healthy controls. High levels of total IgE were in male allergic patients.

CONCLUSION:

High BMI was associated with asthma in females, urticaria/eczema in both genders and atopy in both genders of healthy controls. Higher levels of total IgE were concluded in male patients.

Health and economic burden of obesity in elderly individuals with asthma in the United States

The health and economic burden of obesity among elderly individuals with asthma has not been adequately studied. This study assessed the association between obesity and asthma among the elderly and examined the impact of obesity on asthma-related and total health care costs among elderly individuals with asthma. This was a retrospective analysis of the 2006-2010 Medical Expenditure Panel Survey (MEPS) data. Individuals aged 65 years or older were included in the study. Individuals with asthma were identified by an International Classification of Diseases, Ninth Revision code of 493 or a Clinical Classification Code of 128. Individuals with a self-reported body mass index ≥ 30 kg/m(2) were considered to be obese. Logistic regression was used to assess the relationship between obesity and asthma. Generalized linear models with gamma distribution and log link were used to assess the relationship between obesity and asthma-related and total direct medical costs. All analyses were conducted while accounting for the complex survey design of MEPS. In all, 675 elderly individuals were identified as having asthma, 292 of whom were obese. Obese elderly individuals were more likely to suffer from asthma as compared to the nonobese (odds ratio, 1.71; 95% confidence interval [CI],1.37-2.12). Obesity was a significant predictor of asthma-related costs (β: 0.537; 95% CI: 0.18-0.89; P= 0.003) and total health care costs (β: 0.154; 95% CI: 0.08-0.23; P = 0.001) among elderly individuals with asthma after controlling for sociodemographics and comorbidities. Appropriate weight management measures should be recommended to obese elderly individuals with asthma to improve asthma control and reduce health care costs.

The effect of obesity on the level of fractional exhaled nitric oxide in children with asthma

BACKGROUND

Several studies have demonstrated a relationship between asthma and obesity. However, the results have been conflicting with regard to the relationship between fractional exhaled nitric oxide (FeNO), used as a marker of airway inflammation in asthmatic patients, and obesity. We aimed to evaluate the association of FeNO with obesity and obesity-related metabolic complications in asthmatic and nonasthmatic children.

METHODS

The study population included children aged between 6 and 17 years and consisted of 4 groups: obese asthmatics (n = 52), normal-weight asthmatics (n = 49), obese nonasthmatics (n = 51) and normal-weight nonasthmatics (n = 42). FeNO measurement and spirometry were performed for all patients. To evaluate the metabolic complications, serum lipids, glucose and insulin levels were measured. Insulin resistance (IR) was estimated by the homeostasis model assessment, HOMA-IR. All participants were evaluated for the presence of metabolic syndrome (MS).

RESULTS

The mean age for the 194 subjects participating in the study was 11.6 ± 2.5 years. The FeNO level of asthma patients with MS was not different from those without MS (14.5 ± 8.0 and 16.7 ± 8.7, respectively, p = 0.449). In the nonasthmatic group, subjects with MS had a higher FeNO level than subjects without MS (12.5 ± 5.1 and 17.3 ± 8.3, respectively, p = 0.014). Spearman's rank correlation coefficients revealed a positive correlation between FeNO and body mass index (BMI; p = 0.049, r(2): 0.204) in the nonasthmatic group and after multivariate regression analysis, BMI still persisted as an independent risk factor for FeNO.

CONCLUSION

We found a positive correlation between BMI and FeNO level which suggests a link between obesity and increased airway inflammation in nonasthmatic children.

Pediatric obesity and asthma quality of life

Widely researched as separate entities, our understanding of the comorbid effects of childhood obesity and asthma on quality of life is limited. This article discusses the effects of childhood obesity and asthma on self-reported quality of life in low-income African American teens with asthma. When controlling for the influence of symptom frequency, asthma classification, asthma self-efficacy, and asthma self-care levels, body mass index remains a most important factor in determining self-reported quality of life among teens with asthma. Although overweight and obesity did not change the effectiveness of the asthma intervention program, obesity did affect participants quality of life scores.

Leptin, adiponectin, and ghrelin levels in female patients with asthma during stable and exacerbation periods

OBJECTIVE

The mechanisms underlying the relationship between obesity and asthma have not been fully established. Data in the literature suggest that adipose tissue-derived hormones may be implicated. However, no definite conclusions regarding the role of leptin and adiponectin with asthma are available. No studies have examined the role of ghrelin in asthma.

METHODS

We assessed the circulating concentrations of leptin, adiponectin, and ghrelin in 32 postmenopausal stable asthma patients, 37 female asthmatics during exacerbations and 8 weeks later, and 22 controls. We examined the relationship between the three peptides and indexes of pulmonary function, airway inflammation, and atopy.

RESULTS

Stable asthma patients exhibited higher leptin and lower ghrelin concentrations compared with controls. Patients with severe asthma had higher leptin and lower adiponectin levels versus patients with mild to moderate asthma. Both leptin concentrations and leptin/adiponectin ratio served as markers for discriminating asthma patients from controls on the one hand, and severe from mild to moderate asthmatics on the other. Leptin levels were inversely correlated with both FEV(1)/FVC and FEF(25-75) in patients with mild to moderate asthma. Atopic asthma patients had higher leptin concentrations than nonatopic asthma patients. There was a positive correlation between serum leptin and total IgE levels in atopic asthmatics. Finally, serum leptin levels and leptin/adiponectin ratio were significantly increased during asthma exacerbations, while adiponectin and ghrelin levels were significantly decreased.

CONCLUSION

Our findings suggest that leptin, adiponectin, and ghrelin may play a significant role in the pathogenesis of asthma during both stable state and asthma exacerbation, independent of obesity.

Obesity lowers the threshold of allergic sensitization and augments airway eosinophilia in a mouse model of asthma

BACKGROUND

Clinical and epidemiological studies show a close association between obesity and the risk of asthma development. The underlying cause-effect relationship between metabolism, innate and adaptive immunity, and inflammation remains to be elucidated.

METHODS

We developed an animal model to study the interaction between metabolic abnormalities and experimentally induced asthma. Obesity-susceptible AKR mice were fed with high-fat diet (HFD) or normal low-fat diet (LFD) and subjected to a protocol of ovalbumin (OVA) sensitization and airway allergen challenges followed by assessment of inflammation and lung function.

RESULTS

AKR mice developed obesity and a prestage of metabolic syndrome following HFD. This phenotype was associated with an increase in proinflammatory macrophages (CD11b+/CD11c+) together with higher serum levels of interleukin 6. Obese mice showed increased susceptibility to allergic sensitization as compared to LFD animals. Anti-ovalbumin IgE antibody titers correlated positively and anti-OVA IgG2a antibodies titers correlated negatively with body weight. Airway eosinophilia showed a positive correlation with body weight, whereas mucus production did not change with obesity.

CONCLUSIONS

This obesity model demonstrates that HFD-induced obesity lowers the sensitization threshold in a model of asthma. This finding helps to understand why, particularly during childhood, obesity is a risk factor for the development of allergic asthma.

Underweight and overweight men have greater exercise-induced dyspnoea than normal weight men

INTRODUCTION

Persons with high or low body mass index (BMI), involved in clinical or mechanistic trials involving exercise testing, might estimate dyspnoea differently from persons with a normal BMI.

AIMS

Our objective was to investigate the relationship between BMI and dyspnoea during exercise in normal subjects with varying BMI.

MATERIAL AND METHODS

A total of 37 subjects undertook progressive exercise testing. Subjects were divided into three groups: underweight (UW), normal weight (NW), and overweight (OW). Dyspnoea was estimated using the visual analogue scale (VAS). Spirometry, maximum voluntary ventilation (MVV), and respiratory muscle strength (RMS) were measured.

RESULTS AND DISCUSSION

The intercept of the VAS/ventilation relationship was significantly higher in NW subjects compared to UW (P = 0.029) and OW subjects (P = 0.040). Relative to the OW group, FVC (P = 0.020), FEV(1) (P = 0.024), MVV (P = 0.019), and RMS (P = 0.003) were significantly decreased in the UW group. The greater levels of dyspnoea in UW subjects could possibly be due to decreased RMS. Healthy persons should aim to achieve an optimum BMI range to have the lowest exercise-induced dyspnoea.

BMI-based approach reveals direct impact of metal dust exposure on influenza-associated lung function decrement risk in smelters

Metal dust exposure strongly affects human health, especially for smelters. Little is known, however, about the impact of metal dust exposure on influenza-associated lung function decrement risk in smelters. Different body mass index (BMI) groups were also associated with respiratory diseases. The purpose of this study was to use a probabilistic risk assessment approach to explicitly link occupational metal dust exposure, BMI-correlated health effects, and influenza-associated lung function decrements to investigate potential risk among smelters. Here we showed that (i) influenza A-associated metal dust exposure in SiMn/FeMn/FeCr smelters had slightly higher health risks than that in FeSi/Si-metal's, (ii) BMI≥35 had the highest risk in respiratory infection exacerbations, and (iii) the estimated smelting metal dust induced forced expiratory volume in 1s (FEV(1)) decreasing rates were 0.59 and 1.11 m(3) mg(-1) for FeSi/Si-metal and SiMn/FeMn/FeCr smelters, respectively. Our results suggested that smelters better be aware of severe weight gains (e.g., BMIs from 27-40) because it is likely to lead to 17-25% decrements in lung function. This study provides a novel probabilistic risk assessment framework to quantitatively assess the occupational health risk posed by metal dust exposure associated with influenza infection based on BMI measures.

The Obesity Pandemic: Where Have We Been and Where Are We Going?

Obesity, a new pandemic, is associated with an increased risk of death, morbidity, and accelerated aging. The multiple therapeutic modalities used to promote weight loss are outlined with caution, especially for patients who are very young or old. Except for very rare single gene defects, the inheritance of obesity is complex and still poorly understood, despite active investigations. Recent advances that have shed light on the pathophysiology of obesity are the recognition that 1) excess fat is deposited in liver, muscle, and pancreatic islets; 2) fat tissue secretes a large number of active signaling molecules including leptin, adiponectin, and resistin, as well as free fatty acids; and 3) activated macrophages colonize the adipose tissue. Other candidates for key roles in the causes and consequences of obesity include 1) metabolic programming, where food acts as a developmental regulator; 2) the constellation of defects known as the "metabolic syndrome;" 3) cortisol overproduction in the adipose tissue; and especially, 4) insulin resistance. The possible etiologies of insulin resistance include cytokine excess, elevated free fatty acids, and hyperinsulinemia itself, as with transgenic overproduction of insulin in mice.

Influence of underweight on asthma control

BACKGROUND

Although the association between asthma control and body mass index (BMI) has been thoroughly investigated, most of this work has focused on the influence on asthma incidence or the effect of obesity on asthma control. To date, there have been no published studies on the influence of underweight on asthma control.

METHODS

The aim of this study was to investigate the influence of underweight, as defined by the Japan Society for the Study of Obesity (JASSO), on asthma control in Japanese asthmatic patients. Using data from questionnaire surveys administered by the Niigata Asthma Treatment Study Group, we compared asthma control, as measured by the Asthma Control Test (ACT), between a normal weight group (18.5kg/m2 =< BMI < 25kg/m2) and an underweight group (BMI < 18.5kg/m2).

RESULTS

Of the asthmatic patients who completed the 2008 and 2010 surveys, 1464 and 1260 cases were classified as being in the normal weight group, and 174 and 155 cases were classified as being in the underweight group. The ACT score (median, [interquartile range]) in the underweight group in 2008 (22, [19-24]) and 2010 (23, [19-25]) was significantly lower than that in the normal group in 2008 (23, [20-25]) and in 2010 (24, [21-25]).

CONCLUSIONS

This study is the first, large-scale investigation of the influence of underweight on asthma control, and we have confirmed an adverse influence in a clinical setting. A potential mechanism for this interaction was unknown. Further investigation will be required.

The moderating influence of asthma diagnosis on biobehavioral health characteristics of women of reproductive age

Promoting healthy behaviors to improve pregnancy outcomes requires an understanding of the factors influencing health behaviors among at-risk populations. We hypothesized that women with an asthma diagnosis would have poorer biobehavioral health risk factors and pregnancy outcomes compared to women without an asthma diagnosis. The Central Pennsylvania Women's Health Study (CePAWHS) included a population-based survey examining health status indicators, risk factors and outcomes, and detailed pregnancy histories among 2,002 women (ages 18-45). 213 asthmatics were identified. Compared with Non-asthmatic women (NA), Asthmatic (A) women reported lower rates of excellent health status (45% A vs. 65% NA, P < 0.001), were more likely to be overweight or obese (68% A vs. 50% NA, P < 0.001), and were more likely to have smoked cigarettes during their first pregnancy (25% A vs. 17% NA, P < 0.01). Psychological measures (psychosocial hassles, low self-esteem, depression) were reported more often in asthmatics than non-asthmatics. Also, asthmatics reported a higher incidence of gestational diabetes (10% A vs. 6% of NA, P = 0.05), preterm births (25% A vs. 16% NA, P < 0.01), and had a higher proportion of low birth weight infants (20% A vs. 13% NA, P = 0.03) compared with non-asthmatics. As predicted, asthmatics had poorer biobehavioral risk factors and outcomes compared to non-asthmatics. These findings illustrate the need to target asthmatic women of reproductive age, particularly in this largely rural setting, with interventions to reduce biobehavioral risk factors as part of a strategy to improve pregnancy outcomes.

Epidemiology and management of common pulmonary diseases in older persons

Pulmonary disease prevalence increases with age and contributes to morbidity and mortality in older patients. Dyspnea in older patients is often ascribed to multiple etiologies such as medical comorbidities and deconditioning. Common pulmonary disorders are frequently overlooked as contributors to dyspnea in older patients. In addition to negative impacts on morbidity and mortality, quality of life is reduced in older patients with uncontrolled, undertreated pulmonary symptoms. The purpose of this review is to discuss the epidemiology of common pulmonary diseases, namely pneumonia, chronic obstructive pulmonary disease, asthma, lung cancer, and idiopathic pulmonary fibrosis in older patients. We will review common clinical presentations for these diseases and highlight differences between younger and older patients. We will also briefly discuss risk factors, treatment, and mortality associated with these diseases. Finally, we will address the relationship between comorbidities, pulmonary symptoms, and quality of life in older patients with pulmonary diseases.

Obesity, obesity related disease, and disability

Background

Obesity increases the risk of many chronic diseases and contributes to functional disabilities. We assessed the relationship among obesity and obesity related chronic disease and disability in Korean adults.

Methods

This study used data from the 2005 Korean National Health and Nutrition Examination Survey. A total of 5,462 persons (2,325 men, 3,137 women) aged 20 years and older were included in this analysis. Obesity was measured by body mass index and abdominal obesity was by waist circumference. Information on the presence of chronic diseases was based on the self-report of having been diagnosed by physicians. Functional disability was assessed using the Korean activities of daily living (K-ADL) and the Korean instrumental ADL (K-IADL) scales.

Results

The relationship between obesity and prevalence of obesity-related chronic diseases was higher in the older aged group (>60 years for men, >70 years for women) than in the younger aged group. Waist circumference was more related to a higher prevalence of chronic diseases than body mass index in the younger aged group. Abdominal obesity increased the risk (odds ratio, 2.59; 95% confidence interval, 1.19 to 5.66) of having limitation in activities of daily living for the younger aged men after adjustments for age, smoking status, presence of chronic diseases, and body mass index. Body mass index was not associated with disability in either men or women.

Conclusion

The association between obesity and prevalence of chronic disease differed depending on age and sex. It is important to control abdominal obesity to prevent disability in younger aged men.

Association between body mass index and asthma among Japanese adults: risk within the normal weight range

BACKGROUND

Increasing amounts of data have shown that some Asian populations are more susceptible to increased weight and development of noncommunicable disease than Western populations. However, little is known about the association between increased weight, particularly within the normal range, and the development of asthma among Asian populations.

METHODS

To examine the association between increased body mass index (BMI) and asthma among Japanese adults, data from a nationwide population-based cross-sectional survey of asthma prevalence in Japan were analyzed (n = 22,962; age range 20-79 years). BMIs were classified into 7 categories considering WHO recommendations (cutoff points: 17.00, 18.50, 23.00, 25.00, 27.50 and 30.00), and the association between BMI and the prevalences of asthma as well as asthma symptoms were assessed by multivariate logistic regression.

RESULTS

The prevalences of obesity (BMI ≥ 30.00) in this population were relatively low (males 3.0%, females 2.3%). BMI categories of 25.00 or higher in both genders were significantly associated with an increased risk of asthma compared with the reference category (BMI 18.50-22.99). Even in females with a BMI of 23.00-24.99, the prevalence of asthma significantly increased (adjusted odds ratio 1.49, 95% confidence interval 1.16-1.92) compared with that in the reference category.

CONCLUSIONS

An increase in the prevalence of asthma among Japanese females starts at a BMI of 23.00, which was relatively lower than those reported from Western countries. This finding suggests that the Japanese population is likely to have asthma with a lesser degree of obesity than Western populations.

U-shaped association between body mass index and the prevalence of wheeze and asthma, but not eczema or rhinoconjunctivitis: the ryukyus child health study

BACKGROUND

Studies reporting on the association between obesity and allergies have mostly focused on asthma. Little is known about the relationship of obesity to other allergic diseases, and the information that is available has been inconsistent. We examined the association between body mass index (BMI) and the prevalence of wheeze, asthma, eczema, and rhinoconjunctivitis in Japanese schoolchildren.

METHODS

Study subjects were 24,399 children aged 6-15 years in Okinawa, Japan. Outcomes were based on diagnostic criteria from the International Study of Asthma and Allergies in Childhood. BMI was categorized into five groups; <5th, 5th to 35th, >35th to 65th, >65th to 95th, and >95th percentile groups. Adjustment was made for sex, age, region of residence, number of siblings, smoking in the household, physical activity, paternal and maternal history of allergic disorders, and paternal and maternal educational levels.

RESULTS

The prevalence values of wheeze, asthma, eczema, and rhinoconjunctivitis in the previous 12 months were 10.8%, 7.6%, 6.9%, and 7.6%, respectively. Compared with the referent category (>35th to 65th percentile group), higher percentile categories were positively associated with the prevalence of wheeze. A U-shaped relationship between BMI and asthma was observed. No material associations between BMI percentile categories and the prevalence of eczema or rhinoconjunctivitis were found.

CONCLUSION

These findings suggested that being either underweight or overweight might increase the likelihood of asthma among Japanese schoolchildren.