Time trends in the prevalence of asthma, family history of asthma and atopy in Roman schoolchildren were assessed. The study population consisted of all children (aged 6–14 yrs) attending two primary schools in Rome, situated in urban areas that differed markedly in socioeconomic conditions and environmental pollution. Three questionnaire-based surveys were conducted in 1974, 1992 and 1998 in 2,259, 1,229 and 1,139 children. The prevalence of asthma in males and females increased significantly during 1974–1992 and remained stable from 1992–1998. In age groups born in the subsequent 4-yr periods it increased almost linearly, for children born from 1962–1965 to 1982–1985 (4.4%–12.5%), and remained remarkably stable in children born after 1985. Because the prevalence of asthma had a steeper trend in males than in females (approximately 0.55%·yr−1versus0.25%·yr−1), the male:female asthma ratio increased (1:38 in 1974; 1:84 in 1992 and 1:62 in 1998). No single environmental factor, including area of residence, seemed to influence the prevalence of asthma. Family history of asthma and atopy also increased steadily (0.72%·yr−1and 0.30%·yr−1respectively) more than doubling during the 24-yr study period. The strong relationship between asthma and a family history of atopy not only persisted but also strengthened over time (23.3% of asthmatic children belonged to families with atopic illnesses in 1974 but 44.2% in 1998). The environmental factors that might explain the almost three-fold rise in childhood asthma between 1974 and 1992 remain unknown but the genetic background of the disease has presumably remained unchanged since the early 1970s. The fact that the prevalence of asthma increased no further during the past 6 yrs suggests that the progressive induction of asthma symptoms in genetically predisposed subjects is a self-limiting process that has probably come to an end in the authors' study area.

Student's t -test and the chi-square test were used for the statistical analysis. RESULTSIn all, 282 refluxing and 112 nonrefluxing units were assessed. Renal damage was detected in 188 of 282 units with VUR (67%) and in 18 of 112 (16%) contralateral nonrefluxing kidneys. The mean AU was 18.7% in kidneys with VUR and 29% in nonrefluxing units ( P < 0.001). The mean ( SD ) AU decreased from lower to higher grades of VUR, i.e. grade 0 VUR (group A), 28.97 (9.71); grade 1-3 (group B), 21.28 (8.33); grade 4-5 (group C), 14.78 (8.02). The differences were statistically significant (A vs B, B vs C, both P < 0.001). Renal damage was differently distributed in the three groups: 69 of 109 kidneys (63%) in group C (MS prevalent), 39 of 173 (22.5%) in group B (SS prevalent) and 17 of 112 (15.2%) in group A. There was no significant difference in the distribution of renal damage subtypes in patients aged 2 years (SS 19.6% vs 17.9%, MS 29.6% vs 30.1%, small size 48.2% vs 46.3%). The VUR was severe (group C) in 65% of patients aged <2 years and in 46% aged >2 years (chi-square, P = 0.016). CONCLUSIONSVUR is commonly associated with renal damage. Age (< or >2 years) did not significantly influence the kidney lesion subtype. Reduced parenchymal function (AU) progressively decreased with the severity of VUR. Focal MS, reduced size and relative uptake were significantly more common in severe VUR, leading to multifocal lesions and hypo-dysplasia. Renal scarring was present in up to 15% of contralateral nonrefluxing kidneys. Severe VUR behaved differently from lesser VUR in the renal scan parenchymal uptake.

No abstract

The marked time-related increase in the size of the histamine wheals could help to explain the trend toward an increased prevalence of positive allergen skin test reactions reported during the past years. The causes of increased skin reactivity to histamine remain conjectural.

The aim of this study was to determine the relationship of salivary cotinine levels with individual and household smoking habits and with the season in a sample (n = 146) of Italian schoolchildren aged 9-14 yrs. Active smoking and environmental tobacco smoke were measured by means of a confidential standardized interview with each participating child and by a self-reported questionnaire administered to the parents. Saliva samples were obtained twice: during winter from all children and during spring from a randomly selected subgroup. "Active smokers" were significantly more likely to be males and to live with smoking family members. Frequency of detectable cotinine both in "nonsmokers" and "active smokers" was significantly correlated with the number of cigarettes smoked by household members. However, for any level of smoking by parents detectable cotinine was more likely to be found in "active smokers" than in "nonsmokers". In "nonsmokers", the proportion of subjects with detectable cotinine decreased significantly in spring compared to winter, a finding not observed in "active smokers". In conclusion, we have demonstrated that passive smoking produces most effect in winter, and is linked to the amount and style of the parents' smoking, mainly related to smoking in presence of children. Conversely, salivary cotinine detected in spring appears to be derived mainly from active smoking.