ABSTRACT
AIM: Description of adolescent e-cigarette use over time. METHOD: In 2017 and 2019, 261 adolescents from North Rhine-Westphalia who had used e-cigarettes at least once a month (mean age: 14.9 years; 33.5â% female) took part in a questionnaire study. RESULTS: In 2017, 84 adolescents (32.2â%) reported exclusive e-cigarette use (single users), 177 adolescents were classified as dual users (67.8â%) because they consumed a tobacco product (conventional cigarette and/or hookah) in addition to e-cigarettes. During the observation period of 18 months, 83 adolescents (31.8â%) quit nicotine products altogether. Dual users quit nicotine less often than single users (Nâ=â39 or 22.0â% vs. Nâ=â44 or 52.4â%, pâ<â0.001). Seven single users (8.3â%) did not change their behavior, 11 began to use tobacco exclusively (13.1â%), another 22 (26.2â%) started dual use. Seventy-eight dual users (44.1â%) did not change their behavior, 57 (32.1â%) switched to tobacco use only, 3 dual users (1.7â%) stopped tobacco use, but continued to use e-cigarettes. Taken together, at the end of the study, 10 (5.6â%) of the remaining 178 adolescents consumed only e-cigarettes, while 168 (94.4â%) smoked tobacco or were dual-users. CONCLUSIONS: More than two thirds of all young e-cigarette users and more than three quarters of dual users also used nicotine products 18 months later. The remaining consumers showed a less frequent stay or switch to single use, instead a more frequent use of tobacco or dual use.
Subject(s)
Electronic Nicotine Delivery Systems , Nicotine/administration & dosage , Smoking/epidemiology , Tobacco Products/statistics & numerical data , Tobacco Use/epidemiology , Tobacco, Smokeless/statistics & numerical data , Vaping/epidemiology , Adolescent , Cohort Studies , Female , Humans , Male , Smoking/adverse effectsABSTRACT
CONTEXT: Epigenetic mutations of 11p15 encompassing IGF2 are present in short children with Silver-Russell syndrome (SRS) with high frequency (31-50%). It has been speculated that these mutations characterized by demethylation of ICR1 cause diminished IGF2 expression. OBJECTIVE: We aimed to determine the prevalence of pathologically low IGF-II serum levels in children with SRS. SUBJECTS: SRS was defined by birth weight or length below the 3rd percentile, lack of postnatal catch-up growth, and the presence of two of the following characteristics: typical face, relative macrocephaly, and skeletal asymmetry. Serum samples of 30 patients were available. Mean age was 5.4 +/- 2.1 yr. METHODS: The serum levels of IGF-I, IGF-II, IGF binding protein (IGFBP)-2, and IGFBP-3 were measured by RIA and compared with age-related reference values and with serum concentrations measured in age- and gender-matched controls born small for gestational age (SGA), but lacking major dysmorphic features. Analysis of genomic DNA was possible in a subgroup of children with SRS: the methylation status of the ICR1 locus on 11p15 and the parental origin of chromosome 7 were analyzed in 9 and 23 children, respectively. RESULTS: Demethylation of ICR1 was found in 44% and uniparental disomy in 17% of the tested children with SRS. The median IGF-II serum level in SRS was 441 microg/liter (range, 238-875). This was significantly higher than in the SGA controls: 387 microg/liter (range, 265-596) (P < 0.03), but below the median value of the age-related reference, which was 532 microg/liter. The four children with SRS and ICR1 demethylation had high-normal and normal IGF-II serum levels that were higher than the levels of their SGA controls. IGF-I, IGFBP-2, and IGFBP-3 serum levels were not different between the SRS children and their SGA controls. CONCLUSIONS: Our data render it unlikely that demethylation of ICR1 on 11p15 does cause diminished IGF-II serum levels in children with SRS. This observation does not exclude deficient IGF-II action before birth.