Vocal cord dysfunction (VCD) is a functional respiratory tract disorder resulting from paradoxical adduction of the vocal cords, complicates the diagnosis and management of common respiratory tract problems, including asthma. The recognition of VCD in a patient with atypical or difficult-to-control asthma is critical in minimizing symptoms and potential side-effects associated with treatment of severe asthma. The symptoms of VCD are not unique to the disorder and include cough, wheeze, stridor, dyspnea, hoarseness, and choking. (more…)

In 2004, there were 2.4 million children aged 5 to 14 years, or 5.9% of this population group, with a self-reported asthma attack, with no decrease in prevalence since 1997 1 in spite of the much improved therapies available. In this interval, the number of physician office visits for asthma doubled, from 1.7 to 3.3 million which many leads to asthma morbidity and asthma mortality. (more…)

The genetic basis of asthma heritability has been extensively studied and the studies are yielding some understanding. There is, as yet, no set genetic pattern that predicts presence of asthma or defines it severity. There are usually reasons or risk of asthma factors that makes someone susceptible to asthma and respiratory allergy problems. Asthma doesn’t just happen randomly to anyone without asthma gene factors risk factors.

Let’s consider some asthma risk factors and see how they increase the chance that a individual will have the asthma signs or symptoms of cough, wheezing, as well as shortness of breathing associated with the disease. After determining your personal risk factors for asthma, decide on the ones you can control as well as try to make some lifestyle changes. Avoidance of the risk factors you can control is important in preventing asthma symptoms. While you cannot change your own gender to family history, you can avoid smoking with asthma, breathing polluted air, and obesity. Take control of your asthma by controlling the asthma risk factors. By understanding all of the risk factors, you are able to prevent to control your asthma.

Genetic factors cannot explain the rise in asthma prevalence, morbidity, or mortality. However, a small change in the prevalence of relevant environmental exposures could explain a significant rise in disease prevalence among genetically susceptible individuals. Gene-environment interaction, defined as the co-participation of genetic and environmental factors, is particularly relevant to the etiology of asthma morbidity, especially in individuals who experience a disproportionate burden of environmental exposures. Relevant exposures include smoking, stress, nutritional factors, infections, allergens, and occupational asthma exposures. In addition, racial/ethnic variability in the distribution of genetic polymorphisms can potentially modify the response to pharmacotherapeutic agents, such as the ß 2 -adrenergic receptor. A genetic polymorphism in the ß 2 -adrenergic receptor gene has been associated with asthma severity, as well as with the susceptibility to develop asthma among individuals who smoked.

Childhood asthma happens more frequently in boys than in girls. It is still not known precisely why this occurs even though some experts find a young male’s airway size is small compared to the female’s airway, that may contribute to increased risk of wheezing after a cold or perhaps other viral infection. Around age 20, the ratio of asthma between people is the same. At age 40, more females than men have adult asthma.

The inherited genetic makeup predisposes you to having asthma. In fact, it’s thought that three-fifths of all asthma cases are hereditary. Based on CDC report, if a person has a parent with asthma, there is 3 to 6 times more probably to develop asthma than someone who does definitely not have a parent with asthma.

” class=”index-image” width=”120″ />
A general pattern of factors influencing development of asthma seems to be emerging, including family allergy history/ asthma genetics, smoking, diet, obesity, and inactivity, all of which seem to influence the development of asthma and disease outcomes (Table bellow).

Many clinical or area studies have reported substantially higher rates of asthma prevalence, hospitalization, and mortality among racial and ethnic minorities. However, asthma is also most common among low socioeconomic groups, regardless of race. While black children have higher rates of asthma than white children, most studies have found that black race is not a significant correlate of asthma after controlling for location of residence and socioeconomic status (SES). The basis for the effects of poverty and urban residence on asthma prevalence is not known. One potential asthma factor is allergen exposure and allergen sensitization are common in urban environments. Black children in inner city Atlanta are exposed to high levels of dust mites and cockroach allergen, and a high proportion of the children with asthma were sensitized to these allergens. Litonjua and colleagues also concluded that a large proportion of racial/ethnic differences in asthma prevalence can be explained by factors related to income, area of residence, and level of education.

Asthma Factors that Influence Disease Development and Severity

Income is a determinant of access to health care, and frequently, the quantity and quality of health care available. Persons who have low income, regardless of race or ethnicity, are more likely to be uninsured, to encounter delays or be denied care, to rely on hospital clinics in emergency departments for health services, and to receive substandard care. The usual socioeconomic indicators, education and personal or household income, serve only as surrogates for more complicated correlates of individuals within populations and multiple asthma factors that can impact both on prevalence of asthma and adverse outcomes from the disease.

Studies from Germany comparing the populations of East and West Germany have shown the prevalence of hay fever and asthma as significantly higher in West German children, suggesting that asthma environmental factors explain the difference in prevalence in these ethnically similar populations. Early exposure to infections (as with being in a day-care environment early in life) or exposure to endotoxin (as with growing up on a farm with close exposure to the farm animals) are associated with a decreased prevalence of asthma. In contrast, growing up in an urban environment or generally with an increased standard of living are associated with an increased prevalence of asthma. Such correlates are also present for atopic disorders other than asthma. In fact, Strachan, who noted that prevalence of hay fever was inversely related to family size, was the first to recognize the importance of early exposures on atopic disease. In the USA, asthma is more prevalent in African-Americans and Puerto Ricans. These findings are not explained by the observations on the role of social class in European studies. Given the ethnic differences between African-Americans and whites, these studies may represent gene-by-environment interaction producing varied phenotypic outcomes.

Anti-IgE therapy could be particularly beneficial for patients with concomitant asthma and rhinitis as it targets a common factor in the two diseases. Omalizumab is significantly more efficacious than placebo in preventing asthma exacerbations and in improving disease-related quality of life scores when added to standard asthma and rhinitis therapies. (more…)

Allergic rhinitis is a very common problem associated with poor quality of life, reductions in social and work activities and poor interpersonal relationships. The main goal of the management of allergic rhinitis is to improve the quality of life. Immunotherapy is a specific therapy for allergic rhinitis and several reports have documented the safety and efficacy of this treatment . Safety has been a key issue in immunotherapy and various modalities are being investigated to make allergy immunotherapy more tolerable and safe to administer. (more…)

This population-based cross-sectional study, funded by a UK government agency, aimed to establish the rate of sensitization to food allergens, reported food hypersensitivity, food avoidance and objectively assessed food hypersensitivity in 11- and 15-year-olds living on the Isle of Wight, UK. The researchers approached the teenagers via their schools, and a questionnaire completed by the parents and children formed the basis of capturing data to determine the prevalence of current reported food hypersensitivity and rates of food avoidance. This information was available on 775 individuals aged 11 years and 757 aged 15 years. (more…)

The prevalence of atopic dermatitis is increasing in Western societies. The hygiene hypothesis proposes that this is due to reduced exposure to environmental allergens and infections during early life. The authors examined factors associated with a diagnosis of atopic dermatitis at 3.5 years of age, especially those factors implicated by the hygiene hypothesis. The Auckland Birthweight Collaborative study is a case–control study of risk factors for small-for-gestational-age babies. Cases were born at term with birth weight at or below the 10th centile; controls were appropriate for gestational age, with birth weight above the 10th centile. (more…)

Asthma is a complex syndrome rather than a single disease entity. Different phenotypes with varying prognosis and determinants have been described, particularly over childhood years 2 and will be discussed in detail in the following. For example, transient early wheezing is characterized by the occurrence of wheezing in infants up to the age of 2 to 3 years which disappears thereafter. The main predictor of these wheezing illnesses is premorbid reduced lung function before the manifestation of any wheeze. These decrements in pulmonary function are in part determined by passive smoke exposure in utero 4 and result in symptoms of airway obstruction when infants get infected with respiratory viruses. (more…)

Natural history studies with the following design features provide a firm epidemiologic foundation for risk factor assessments and etiologic hypotheses:
(1) long-term cohort studies of a prospective design minimize biases resulting from poor parental recall;
(2) multiple evaluations over time provide important checkpoints during the dynamic period of childhood growth and development; and
(3) the inclusion of objective disease measurements strengthens these studies by validating subjective disease assessments (i.e. questionnaire data). (more…)