Genetic and Perinatal Risk Factors for Asthma Onset and Severity: A Review and Theoretical Analysis

Control and severity of asthma during pregnancy are associated with asthma incidence in offspring: two-stage case–control study

“…As expressed by Dombrowski, in pregnancy, ''poor control of asthma leading to chronic or episodic fetal hypoxia is thought to be important'' [20]. As childhood asthma has been associated with an impaired development of the lungs [21,38,39], uncontrolled maternal asthma during pregnancy, especially in the course of asthma exacerbations, could trigger a transient but important hypoxic state in the fetus that, by affecting lung development, could subsequently increase the likelihood of the baby to develop asthma during childhood [23].…”

“…Environmental triggers, such as maternal allergen exposure or maternal infections during pregnancy, along with maternal antibodies and intra-uterine cytokine profile, have been suspected to promote the skewing towards the expression of a Th2-type immunity in the fetus [1,[24][25][26][27][28]. In addition, the influence of genetic factors on asthma susceptibility is known to be important [23]. Consequently, and in agreement with a recently proposed hypothesis [19], a pregnant female with uncontrolled and severe asthma during pregnancy might be providing her child with an environment and polymorphisms that could increase the risk of developing asthma.…”

“…As up to 55% of patients suffering from asthma with moderate-to-severe severity may have experienced asthma exacerbations at least once during pregnancy [17,18], this could be proposed as an important feature in the development of childhood asthma. Moreover, potential explanatory hypotheses include impaired lung development, which may result from maternal hypoxia occurring among moderate-to-severe asthmatic females experiencing uncontrolled asthma during pregnancy, or may be due to the fact that those females may have characteristics enhancing the propensity of a child to develop a T-lymphocyte helper (Th) type 2-biased immunity [10,[19][20][21][22][23][24][25][26][27][28].…”

Assessment of Impact of Environmental Causative Factors on Severity of Asthma in Children

“…Risk factors are genetic predisposition (family history of atopy or asthma), perinatal factors (low birth weight, prematurity), exposure to allergens, infec tions (respiratory infections, especially those caused by respiratory syncytial virus), environmental air pollu tion, tobacco smoke, diet and obesity. 11 Some of the differences are attributable to differences in the environ mental exposures and healthcare infrastructure in India while others could be truly genetic or ethnic in origin. The review of literature shows a large variation in data with respect to the prevalence of asthma.…”

Prevalence of Asthma among School Children Belonging to High and Low Socio Economic Status

“…Genetic predisposition is indicated by family history of atopy or asthma. Urbanization, air pollution and environmental tobacco smoke exposure are also contributing factors in children as in adults 4. Low birth weight, prematurity, respiratory infections, especially those caused by respiratory syncytial virus, diet and obesity are other risk factors which showed varying influence on asthma 5 . It is important to establish in a predisposed individual, which environmental factors might influence the development of asthma.…”