Artemis Tsitsika

A genome-wide association study of anorexia nervosa

Anorexia nervosa (AN) is a complex and heritable eating disorder characterized by dangerously low body weight. Neither candidate gene studies nor an initial genome-wide association study (GWAS) have yielded significant and replicated results. We performed a GWAS in 2907 cases with AN from 14 countries (15 sites) and 14 860 ancestrally matched controls as part of the Genetic Consortium for AN (GCAN) and the Wellcome Trust Case Control Consortium 3 (WTCCC3). Individual association analyses were conducted in each stratum and meta-analyzed across all 15 discovery data sets. Seventy-six (72 independent) single nucleotide polymorphisms were taken forward for in silico (two data sets) or de novo (13 data sets) replication genotyping in 2677 independent AN cases and 8629 European ancestry controls along with 458 AN cases and 421 controls from Japan. The final global meta-analysis across discovery and replication data sets comprised 5551 AN cases and 21 080 controls. AN subtype analyses (1606 AN restricting; 1445 AN binge–purge) were performed. No findings reached genome-wide significance. Two intronic variants were suggestively associated: rs9839776 (P=3.01 × 10−7) in SOX2OT and rs17030795 (P=5.84 × 10−6) in PPP3CA. Two additional signals were specific to Europeans: rs1523921 (P=5.76 × 10−6) between CUL3 and FAM124B and rs1886797 (P=8.05 × 10−6) near SPATA13. Comparing discovery with replication results, 76% of the effects were in the same direction, an observation highly unlikely to be due to chance (P=4 × 10−6), strongly suggesting that true findings exist but our sample, the largest yet reported, was underpowered for their detection. The accrual of large genotyped AN case-control samples should be an immediate priority for the field.

Risk factors and psychosocial characteristics of potential problematic and problematic internet use among adolescents: A cross-sectional study

BackgroundProblematic internet use (PIU) is associated with a plethora of psychosocial adversities. The study objectives were to assess the determinants and psychosocial implications associated with potential PIU and PIU among adolescents.MethodsA cross-sectional study design was applied among a random sample (n = 866) of Greek adolescents (mean age: 14.7 years). Self-completed questionnaires, including internet use characteristics, Young Internet Addiction Test, and Strengths and Difficulties Questionnaire, were utilized to examine the study objectives.ResultsAmong the study population, the prevalence rates of potential PIU and PIU were 19.4% and 1.5%, respectively. Multinomial logistic regression indicated that male gender (Odds Ratio, OR: 2.01; 95% Confidence Interval, 95% CI: 1.35-3.00), as well as utilizing the internet for retrieving sexual information (OR: 2.52; 95% CI: 1.53-4.12), interactive game playing (OR: 1.85; 95% CI: 1.21-2.82), and socialization, including chat-room use (OR: 1.97; 95% CI: 1.36-2.86) and email (OR: 1.53; 95% CI: 1.05-2.24), were independently associated with potential PIU and PIU. Adolescents with potential PIU had an increased likelihood of concomitantly presenting with hyperactivity (OR: 4.39; 95% CI: 2.03-9.52) and conduct (OR: 2.56; 95% CI: 1.46-4.50) problems. Moreover, adolescent PIU was significantly associated with hyperactivity (OR: 9.96; 95% CI: 1.76-56.20) and conduct (OR: 8.39; 95% CI: 2.04-34.56) problems, as well as comprehensive psychosocial maladjustment (OR: 8.08; 95% CI: 1.44-45.34).ConclusionsThe determinants of potential PIU and PIU include accessing the internet for the purposes of retrieving sexual information, game playing, and socialization. Furthermore, both potential PIU and PIU are adversely associated with notable behavioral and social maladjustment among adolescents.

Determinants of Internet Addiction among Adolescents: A Case-Control Study

Internet Addiction (IA) is associated with adverse psychosocial development and mental disorders. The study aims were to evaluate the psychosocial profiles and psychiatric comorbidities associated with IA among adolescents. A case-control study was conducted among 129 adolescents in the outpatient setting of the Adolescent Health Unit of the Second University Department of Pediatrics in Athens, Greece. The case group consisted of 86 adolescents with IA as evaluated following psychiatric interview with two independent examiners. The control group consisted of 43 adolescents without IA, frequency matched for age and gender with case group participants. The study findings indicated that adolescents with IA were significantly more likely to have divorced parents (p = 0.012) and/or dysfunctional familial relationships (p < 0.0001). The proportion of adolescents with poor academic performance (p < 0.0001) and unexcused school absences (p = 0.004) was greater among those with IA. Moreover, approximately two-thirds of the adolescents with IA were engaged in high-risk behaviors (p < 0.0001). Finally, adolescents with IA were 3.89 times more likely to present with comorbid psychiatric conditions (CI 95%: 1.19–12.70), including depression (10.5 vs. 0%; p = 0.022). Adolescent IA is associated with deterred familial functions, poor academic performance, engagement in high-risk behaviors, and an augmented likelihood for depression.

Online Social Networking in Adolescence: Patterns of Use in Six European Countries and Links With Psychosocial Functioning

PURPOSE Online communication tools, such as social networking sites (SNS), have been comprehensively embraced by adolescents and have become a dominant daily social practice. Recognizing SNS as a key context of adolescent development, this study aimed to investigate associations between heavier SNS use, and adolescent competencies and internalizing problems. METHODS Data was collected in six European countries: Greece, Spain, Poland, the Netherlands, Romania, and Iceland. Participants were 10,930 adolescents aged 14-17 years (F/M: 5,719/5,211; mean age 15.8 ± .7 years); 62.3% were aged 14-15.9 years and 37.7% were aged 16-17.9 years. Participants reported on their use of online communication tools, and their general competencies and internalizing problems (Youth Self Report). RESULTS SNS are both ubiquitous--used by 70% of adolescents--and engaging, given that 40% of users spend 2 or more hours daily on SNS (labeled heavier SNS use). Heavier SNS use was associated with more internalizing problems, and the relation was consistently more pronounced among younger adolescents. Moreover, heavier SNS use was associated with lower academic performance and lower activities scores, especially for younger adolescents. In contrast, among older adolescents heavier SNS use was positively associated with offline social competence. CONCLUSIONS Although heavier SNS use is associated with higher social competence for older adolescents, it is also associated with increased internalizing problems and diminished competencies in academics and activities, especially for younger adolescents. Age, capturing developmental differences in social and regulatory skills, appears to moderate the effects of heavier SNS use on adolescent functioning.

Adolescent pornographic internet site use: a multivariate regression analysis of the predictive factors of use and psychosocial implications.

The study objectives were to evaluate the prevalence, predictors, and implications of pornographic Internet site (PIS) use among Greek adolescents. A cross-sectional study was conducted among 529 randomly selected Greek high school students. The prevalence of overall PIS use was 19.47% (n = 96). Among PIS users, 55 (57.29%) reported infrequent and 41 (42.71%) reported frequent PIS use. The predictors of infrequent PIS use included male gender (adjusted odds ratio [AOR] = 8.33; 95% confidence interval [CI] = 3.52-19.61), Internet use for sexual education (AOR = 5.26; 95% CI = 1.78-15.55), chat rooms (AOR = 2.95; 95% CI = 1.48-5.91), and purchases (AOR = 3.06; 95% CI = 1.22-7.67). The predictors of frequent PIS use were male gender (AOR = 19.61; 95% CI = 4.46-83.33), Internet use for sexual education (AOR = 7.39; 95% CI = 2.37-23.00), and less than 10 hours per week Internet use (AOR = 1.32; 95% CI = 1.10-1.59). Compared to non-PIS users, infrequent PIS users were twice as likely to have abnormal conduct problems (odds ratio [OR] = 2.74; 95% CI = 1.19-6.28); frequent PIS users were significantly more likely to have abnormal conduct problems (OR = 4.05; 95% CI = 1.57-10.46) and borderline prosocial score (OR = 4.22; 95% CI = 1.64-10.85). Thus, both infrequent and frequent PIS use are prevalent and significantly associated with social maladjustment among Greek adolescents.

Cyberbullying victimization prevalence and associations with internalizing and externalizing problems among adolescents in six European countries

More than one in five of European adolescents reported cyberbullying victimization.The prevalence rate of cyber victimization was higher among girls than boys.The prevalence rate was highest in Romania while the lowest was in Spain.Externalizing, internalizing and academic problems were associated with cyber victimization. Cyberbullying victimization is an important adolescent health issue. The cross-national study aimed to investigate the prevalence of cyber victimization and associated internalizing, externalizing and academic problems among adolescents in six European countries. A cross-sectional school-based study of 14-17year-old adolescents (N=10,930; F/M: 5719/5211; mean age 15.8?0.7years) was conducted in Spain, Poland, the Netherlands, Romania, Iceland and Greece. In total, 21.4% of adolescents reported cyber victimization in the past 12months. Reports were more frequent among girls than boys (23.9% vs. 18.5%), and among the older adolescents compared to the younger ones (24.2% vs. 19.7%). The prevalence was highest in Romania and Greece (37.3% and 26.8%) and lowest in Spain and Iceland (13.3% and 13.5%). Multiple logistic regression analysis indicated that cyber victimization was more frequent among adolescents using the internet and social networking sites for two or more hours daily. Multiple linear regression analysis showed that externalizing, internalizing and academic problems were associated with cyber victimization. Overall, cyber victimization was found to be a problem of substantial extent, concerning more than one in five of the studied European adolescents. Action against cyber victimization is crucial while policy planning should be aimed at the prevention of the phenomenon.

Serum S100β Protein in Children With Acute Recurrent Headache: A Potentially Useful Marker for Migraine

Objective.—To examine the role of glia‐derived S100β protein and to evaluate its use as a biochemical marker in childhood acute recurrent headache.

Prevalence of different HPV types and estimation of prognostic risk factors based on the linear array HPV genotyping test.

The aim of the study was to evaluate the prevalence and risk factors of HPV in a gynecologic population attending outpatient clinics using two new molecular tests. The Amplicor HPV test and the Linear Array (LA) HPV Genotyping test were used for the detection of HPV DNA in 320 women. Multiple logistic regression was used to identify independent prognostic factors of HPV positivity. The agreement between the two methods in terms of their qualitative results was 89.3% (kappa: 0.63). Based on the LA results, the overall prevalence of HPV DNA was 49.1%, 95% confidence interval (95% CI: 43.5%, 54.7%). The prevalence of high‐risk HPV types was 30.3%. The predominant types were HPV‐6 (24.8%) and HPV‐16 (20.4%). Among women with normal cytology, the prevalence of HPV was much higher in those presenting other findings, such as inflammation, than those without other abnormal findings (49.5% vs. 31.5%). On the basis of multivariate analysis, the risk of HPV infection was higher among women with multiple sexual partners [>3 vs. 1: OR = 3.1, 95% CI: (1.5, 7.2)], Pap smear findings [low/high‐grade lesions vs. negative: OR = 2.8, 95% CI: (1.2, 6.5)], the presence of warts [yes vs. no: OR = 3.0, 95% CI: (1.5, 6.3)] and no history of child birth [no vs. yes: OR = 2.6, 95% CI: (1.0, 6.7)]. Younger age was an additional risk factor for HPV infection with carcinogenic genotypes [OR for 1 year increase = 0.93, 95% CI: (0.89, 0.98)]. J. Med. Virol. 81:2059–2065, 2009.

Association between problematic internet use, socio-demographic variables and obesity among European adolescents

BACKGROUND Overweight of children and adolescents continues to be an important and alarming global public health problem. As the adolescents time spent online has increased, problematic internet use (PIU) potentially leads to negative health consequences. This study aimed to examine the relation between PIU and overweight/obesity among adolescents in seven European countries and assess the effect of demographic and lifestyle factors recorded in the European Network for Adolescent Addictive Behaviour (EU NET ADB) survey (www.eunetadb.eu). METHODS A cross-sectional school-based survey of 14- to 17-year-old adolescents was conducted in seven European countries: Germany, Greece, Iceland, the Netherlands, Poland, Romania and Spain. Anonymous self-completed questionnaires included sociodemographic data, internet usage characteristics, school achievement, parental control and the Internet Addiction Test. Associations between overweight/obesity and potential risk factors were investigated by logistic regression analysis, allowing for the complex sample design. RESULTS The study sample consisted of 10 287 adolescents aged 14-17 years. 12.4% were overweight/obese, and 14.1% presented with dysfunctional internet behavior. Greece had the highest percentage of overweight/obese adolescents (19.8%) and the Netherlands the lowest (6.8%). Male sex [odds ratio (OR) = 2.89, 95%CI: 2.46-3.38], heavier use of social networking sites (OR = 1.26, 95%CI: 1.09-1.46) and residence in Greece (OR = 2.32, 95%CI: 1.79-2.99) or Germany (OR = 1.48, 95%CI: 1.12-1.96) were independently associated with higher risk of overweight/obesity. A greater number of siblings (OR = 0.79, 95%CI: 0.64-0.97), higher school grades (OR = 0.74, 95%CI: 0.63-0.88), higher parental education (OR = 0.89, 95%CI: 0.82-0.97) and residence in the Netherlands (OR = 0.49, 95%CI: 0.31-0.77) independently predicted lower risk of overweight/obesity. CONCLUSIONS The results indicate an association of overweight/obesity with PIU and suggest the importance of formulating preventive public health policies that target physical health, education and sedentary online lifestyle early in adolescence with special attention to boys.

Human Papilloma Virus infection in sexually active adolescent girls

PURPOSE Adolescents are a vulnerable group with regard to sexually transmitted infections, including Human Papilloma Virus (HPV). This is thought to be both because of their more liberal sexual behavior and also the relative immaturity of their genital tract. The aim of the study was to examine trends in HPV infection among sexually active adolescents attending for a sexual health screen. METHODS Sexually active adolescents were offered cervical screening, HPV typing and conventional genital cultures as part of a sexual health prevention protocol. Participating adolescents also completed a sexual health questionnaire. RESULTS Between January 2008 and July 2011, 149 sexually active girls were examined for reproductive health issues (mean age 17.3 years). 62 (42%) tested positive for HPV DNA, 30 were infected by multiple types and 54 had at least one high risk type identified. The most commonly identified HPV DNA was for low risk type 42 (15 cases, 7.8%), followed by high risk types 51 (14 cases, 7.3%) and 59 (11 cases, 5.7%). E6-E7 mRNA expression was detected in 16 girls (11%), of which half were for HPV 16. Girls who tested positive for HPV DNA and mRNA had similar age at sexual debut with those that tested negative (15.1 years in all groups) but had on average more sexual partners (4.1 vs 1.9 p=0.007). Only 9 girls in this cohort had been vaccinated against HPV. Approximately half of the girls reported using inadequate or no contraception. CONCLUSIONS HPV infection rate was high in our sample. Furthermore a high percentage was infected with high risk types and a proportion of girls demonstrated mRNA HPV expression. As age at first sexual intercourse drops, vaccination against HPV and sexual education should be instituted in early adolescence, in order to reduce long term reproductive sequelae of unsafe sexual practices.