ABSTRACT
Bronchial reactivity to carbachol, estimated by the PD65, the provocation dose of inhaled carbachol inducing a 65% increase of baseline respiratory resistance, was measured in 355 asthmatic children (age 8.7 +/- 2.6 years) and 149 healthy children (age 11.8 +/- 2.3 years). The frequency distribution of PD65 showed apart from 2 minima at 480 micrograms and 960 micrograms 2 significant peaks at 240 micrograms (p = 0.003) and 1200 micrograms (p = 0.01) to carbachol, reflecting a hyperreactive class (PD65 < 480 micrograms), an intermediate class (481 micrograms < PD65 < 960 micrograms) and a normo-reactive class (PD65 > 961 micrograms). The intermediate class is characterised by a considerable overlap between "health" and "disease". However, taking into account the degree of air pollution in which healthy children are living (best related factor to specificity) and the type of initial lung function disorder in asthmatic children, (the MEF50 to be the best related factor for specificity), weighed specificity and sensitivity improved from 64 to 88%. Evaluating bronchial responsiveness in children, such interfering factors should be strongly considered.
Subject(s)
Asthma/physiopathology , Bronchi/physiology , Adolescent , Bronchi/physiopathology , Bronchial Hyperreactivity , Bronchial Provocation Tests , Carbachol , Child , Child, Preschool , Female , Humans , Male , Sensitivity and SpecificityABSTRACT
To investigate the effects of air pollution on the respiratory health of children, a study was undertaken in the southern part of Switzerland covering 312 school children who lived in two zones with significantly different concentrations of NO2. In the more urban area the mean NO2 measured over a period of 10 months was 36.2 +/- 9.5 micrograms/m3 (25 14-day values greater than 40) compared to the mean of the second, rural area of 26.2 +/- 10.4 micrograms/m3 (6 14-day values greater than 40). Respiratory health was evaluated by determination of bronchial reactivity to Carbachol in 5 diagnostic groups (healthy: 109; healthy with positive family history of atopy: 60; allergic but not asthma: 59; asthma: 55; and "unclear cough": 29) by the technique of group specific sampling. The study shows differences in the incidence of bronchial hyperreactivity in children (PD65 less than 900 micrograms Carbachol). Within the 5 diagnostic groups, however, this distinction was significant only in the group of healthy subjects (p less than 0.005). In the other diagnostic groups the influence of the various trigger factors such as respiratory tract infections, allergen exposure, parental smoking and (last but not least) drug treatment seems to be as important as that of air pollution.
Subject(s)
Air Pollutants/adverse effects , Allergens , Respiration/drug effects , Respiratory Hypersensitivity/chemically induced , Adolescent , Asthma/chemically induced , Bronchial Provocation Tests , Carbachol , Child , Female , Humans , Male , Nitrogen Dioxide/adverse effects , Rural Population , Switzerland , Urban PopulationABSTRACT
If hypoglycemia unawareness in diabetes is related to human insulin, its use would mean an increased risk of unconscious hypoglycemia. In a prospective study in 59 children treated from onset of diabetes by either human or porcine insulin of equal purity for a mean observation period of more than 3 years, no significant difference in the incidence of hypoglycemic coma was detected: 9/29 (31%) of the children treated by human insulin compared to 8/30 (27%) of those treated by porcine insulin had 1 or more severe hypoglycemic episodes. At the time of the first coma there was no significant difference in age, duration of diabetes, insulin dose, or HbA1 between the groups. Thus, human insulin is not considered to be an additional risk factor for the development of hypoglycemic coma in diabetic children.
