The article at Frischer et al on maternal smoking and peak melt variability in this issue of Chest (see page 1133) is notable the one and the other for its subject matter and its methods With regard to the modes there is an increased interest in the use of peak roll on in both asthma research and care.

The article at Frischer et al on maternal smoking and peak melt variability in this issue of Chest (see page 1133) is notable the one and the other for its subject matter and its methods

With regard to the modes there is an increased interest in the use of peak roll on in both asthma research and care.[1] Peak result has certain disadvantages. Peak roll on is primarily an index of large airway flow[2] Its major determinants are large airway size, expiratory respiratory muscle power and lung and chest wall recoil. It is more variable and les reproducible than the [FEVsub1][34] It lacks sensitivity in detecting small airway obstruction or mild disease.[5] lately interest has been focused upon using peak flow variability, set forthed in a variety of ways, as an index of bronchial responsiveness.[6,7] Although there is a reasonably pious correlation between these two indices, their relationship may be complementary. Additionally, peak run lacks specificity, identifying only a subset of responsive subjects[8] Despite these difficulties and uncertainties, the originates of Frischer et al are consistent with those of Martinez et al,[9] who originate an association between bronchial responsiveness to carbachol and parental smoking in 9-year-old lads The ability of Frischer and coworkers to demonstrate significant correlations of peak liquefy variability with maternal smoking is likely to stimulate further research upon peak flow monitoring as an important area of asthma investigation.

With regard to proceeds the association of maternal cigarette smoking with peak come variability demonstrated by Frischer et al highlights the importance of maternal cigarette smoking in relation to asthma incidence and severity.

It has been well known that maternal cigarette smoking aggravates asthma symptoms[10,11] and bronchial responsiveness[11,12] in patients with an established diagnosis of the disease. This increase in clinical and physiologic measures of severity is correlated with an increased use of health services, notably urgency room visits,[13] and a decrease in asthma severity with maternal smoking cessation.[14] Thus, there is no question that maternal cigarette smoking is an important exacerbating factor in established disease.

Three things remain unclear: Does maternal cigarette smoking influence the progressive growth of asthma? What is the relative importance of pre- versus postnatal exposure? What is the mechanism on which maternal smoking exerts its effects?

In considering mechanisms and susceptible subgroup the data are conflicting, at best. At least couple studies have linked maternal cigarette smoking to skin-test reactivity in older children.[9,15] Neither consideration considered the relative importance of pre- versus postnatal position Other studies have failed to confirm the association of maternal smoking and skin-test reactivity.[16] Frischer and coworkers support a nonatopic mechanism, as their positive association was confined to nonatopic enthralls They note, however, that lack of an association in the atopic bring under rules might possibly be due to smoking cessation among atopic families. A summary of all existing data proposes that the conflicting results with regard to atopy may be explained through lack of large longitudinal studies that clearly establish the prenatal and postnatal in all senses status of the child, measure the relevant covariates, and pursue the cohort longitudinally from birth one as well as the other to eliminate selection away from smoking in the highly susceptible and to allow for a determination of the relative importance of pre- versus postnatal exposure

of the like kind studies take on added importance because there is a growing dead body of evidence suggesting that maternal cigarette smoking, either in utero or during the first year of life, is associated with the growth of asthma. At least three studies have documented that maternal cigarette smoking is associated with the charge of asthma and infantile eczema during the first year of life.[17-19] Weitzman and coworkers[17] performed a cross-sectional analysis in which they examined the relationship of maternal cigarette smoking to asthma incidence during the first year of life using data from a national health interview measure and estimate The odds of developing asthma in infants of smoking mothers was 20 relative to infants of nonsmoking mothers. The influence of family history of allergy, lower respiratory tract illness, and diet was not examined. Martinez and coworkers,[18] utilizing data from the Tucson Epidemiologic cogitation found a similar estimate for the issue of maternal cigarette smoke exposing and its influence on asthma during the first 2 years of life. In that research the effect seemed to predominate in women of reasonable socioeconomic status, as indicated through less than a high denomination education. Again, the relative importance of pre- versus postnatal front and the effect of other putative risk factors, mainly allergy and lower respiratory tract illness, were not examined. In a randomized mastery trial of allergen avoidance and its influence forward allergic disorders of infancy, parental cigarette smoking was originate to be a risk factor for the exhibition of allergy, whether only common parent or both parents smok The magnitude of the meaning was equal to the issue of allergen exposure in this study[19] Although this research independently controlled for allergen prospect and diet, the relative importance of pre- versus postnatal exposing to environmental tobacco smoke was not examined.

...