Airway response to exercise and methacholine in children with respiratory symptoms

Article Abstract:

Asthma is used to describe respiratory conditions that are accompanied by increased resistance to air flow and enhanced sensitivity of the bronchi, or lower airways. The diagnosis of asthma may be difficult due to the lack of specific symptoms. The enhanced responsiveness of the airways to a variety of stimuli may serve as an indicator for the diagnosis of asthma. However, only two-thirds of asthmatics have enhanced airway responsiveness, and one-third of asthmatics with increased bronchial responsiveness have no symptoms. The severity of increased bronchial responsiveness and the ability to reverse this condition must be considered in the diagnosis of asthma. The stimuli used to test airway responsiveness include exercise, histamine, and methacholine; their effects have not been extensively studied. (Histamine is responsible for allergic symptoms; methacholine constricts the bronchi, or lower airway.) The effects of exercise and methacholine on airway responsiveness were assessed in 30 children with atopy and 30 nonatopic children (7 to 8 years). Atopy is the ability to produce high levels of immunoglobulin E, an immune protein directed against common allergens, or substances that produce symptoms of allergy (such as nasal congestion, tearing, sneezing, wheezing, coughing, and itchy rash). The effects of exercise and methacholine were not correlated in children with symptoms of asthma. However, the airways of atopic children were more responsive to the two stimuli than those of nonatopic children. Analysis indicated that although increased bronchial sensitivity to exercise and methacholine is associated with a diagnosis of asthma, the relation between methacholine and exercise is complex. This suggests that exercise and methacholine are involved in two separate mechanisms which lead to impaired airway function. (Consumer Summary produced by Reliance Medical Information, Inc.)

Diagnosis, Physiological aspects, Exercise, Allergy in children, Pediatric allergy

---

Longitudinal study of cholesterol values in 68 children from birth to 11 years of age

Article Abstract:

Coronary artery disease is a major cause of illness and death in industrialized countries. This disease is strongly related to dietary factors, and effective programs to decrease disease occurrence have been started in the United States. Change in the United Kingdom has been slow, however. The disease process is thought to begin in childhood, a time when lifestyles are also formed. This study of blood lipid (fat) levels in 68 British children (37 female and 31 male) was done to provide reference values; blood tests were performed regularly from birth to age 11. Average blood cholesterol levels increased rapidly from 1.8 millimoles per liter (mmol/l) at birth to about 4.2 mmol/l at four months of age, and were then stable at between 4 and 5 mmol/l up to age 11. Girls tended to have higher levels than boys. Blood cholesterol levels were higher than those reported for American children. Levels of HDL (high-density-lipoprotein) cholesterol, for which higher levels are associated with lower risk of coronary artery disease, were not correspondingly higher, with average values of 1.22 mmol/l at age 5 and 1.53 mmol/l at age 10. Commonly used American standards consider that for total cholesterol, levels above 5.18 mmol/l (200 milligrams per deciliter) indicate a need for dietary intervention. Forty-two percent of the children in this study met or exceeded this level. These results are suggestive when considering the continuing high rate of coronary artery disease in Great Britain. Britain should follow the American example and provide public education about the need to alter dietary habits, addressed to whole families, including children. (Consumer Summary produced by Reliance Medical Information, Inc.)

Health aspects, United Kingdom, Prevention, Children, Demographic aspects, Coronary heart disease, Child health, Hypercholesterolemia, Great Britain

---

Natural history of asthma in childhood - a cohort study

Article Abstract:

Information about the natural history of asthma is limited, although this respiratory disorder affects at least 10 percent of children. Recurrent wheezing has been linked to atopy, a type of allergy to which susceptibility is inherited, and atopy is associated with an increased risk of developing childhood asthma. The natural history of childhood asthma was assessed in 67 infants with a high risk of atopy. The children were followed for 11 years. Atopy developed in 35 children and tended to be more prevalent among older children. Eczema, a chronic inflammatory skin disorder, affected 46 percent of children; wheeze was prevalent in 63 percent; and hay fever developed in 56 percent. The prevalence of hay fever increased with age, whereas that of eczema decreased with age. The prevalence of wheeze peaked before the age of two years and then increased. Wheezing initially developed before two years of age in 21 children, but did not recur thereafter. Wheezing developed after two years of age in 21 children, including 17 with persistent wheezing at 11 years and 12 with increased sensitivity to histamine, which constricts the airways. Atopy developed in 10 children who developed wheezing before two years of age and 20 children with persistent wheezing at 11 years. The findings suggest that childhood asthma is a mixed condition and supports the relation between wheezing and atopy. (Consumer Summary produced by Reliance Medical Information, Inc.)

Evaluation, Causes of, Risk factors, Allergy, Wheeze, Wheezing

Similar abstracts:

• Abstracts: Pharmacokinetics of prednisolone in children with nephrosis
• Abstracts: Pulpal responses to ionomer cements - biological characteristics
• Abstracts: Steroid hormone abnormalities in women with severe idiopathic constipation. DNA probes for diagnosis of intestinal infection
• Abstracts: Clinical and endocrine response to pulsatile intravenous gonadotropins in refractory anovulation. The role and use of progestogens
• Abstracts: The long-term course of Lyme arthritis in children. The overdiagnosis of Lyme disease. Leflunomide or methotrexate for juvenile rheumatoid arthritis

This website is not affiliated with document authors or copyright owners. This page is provided for informational purposes only. Unintentional errors are possible.