Background: When assessing the association between a factor X and a subsequent outcome Y in observational studies, the question that arises is what are the variables to adjust for to reduce bias due to confounding for causal inference on the effect of X on Y. Disregarding such factors is often a source of overestimation because these variables may affect both X and Y. On the other hand, adjustment for such variables can also be a source of underestimation because such variables may be the causal consequence of X and part of the mechanism that leads from X to Y. Methods: In this paper, we present a simple method to compute control variables in the presence of age at onset data on both X and a set of other variables. Using these age at onset data, control variables are computed that adjust only for conditions that occur prior to X. This strategy can be used in prospective as well as in survival analysis. Our method is motivated by an argument based on the counterfactual model of a causal effect. Results: The procedure is exemplified by examining of the relation between panic attack and the subsequent incidence of MDD. Conclusions: The results reveal that the adjustment for all other variables, irrespective of their temporal relation to X, can yield a false negative result (despite unconsidered confounders and other sources of bias).

This study investigates the patterns in nonword repetition performance of children with a developmental language disorder and bilingual children. It has been shown by previous research that both children with developmental language disorder and bilingual children tend to perform poorly in nonword repetition tasks. As these tasks are one of the tools often used for diagnosing markers of DLD in young children, diagnosing bilinguals with DLD proves to be difficult, since both of the groups exhibit a poor performance. An analysis of the patterns found in NWR performance of bilingual children and children with DLD might shed more light onto the issue. The study focuses on analysing the performance in a widely used assessment task - The Children's Test of Nonword Repetition. Three samples of data were analysed. The first sample of data consisted of monolingual English-speaking children diagnosed with a developmental language disorder. The second sample of data consisted of Czech-English bilingual children from international schools in Prague who started acquiring English at the time of birth, i.e. simultaneous bilinguals. The third and final sample consisted of Czech- English bilingual children from international schools in Prague who started acquiring English after one year of age, i.e. sequential bilinguals....

Föreliggande studie undersökte relationen mellan startålder och slutlig behärskning i fonologi och icke-fonologi (ett samlingsbegrepp för morfosyntaktisk och idiomatisk brytning). Deltagarna var 200 spansktalande andraspråkstalare av svenska, 20 modersmålstalare av svenska (kontrollgrupp) och 28 lyssnare med svenska som modersmål. Slutlig förmåga i fonologi och icke-fonologi mättes genom två brytningsbedömningar av lyssnargruppen, en där talarnas faktiska röster användes för att mäta fonologisk förmåga och en där en syntetisk röst användes för att mäta icke-fonologisk förmåga. Studiens resultat visade att det fanns en stark negativ korrelation mellan startålder och slutlig behärskning för både fonologisk och icke-fonologisk förmåga. Korrelationen var starkare för fonologi än för icke-fonologi. Starålder visades även vara den starkaste prediktorn för inföddlik slutlig behärskning, även efter kontroller av andra prediktorer som ålder, vistelsetid i Sverige och grad av andraspråksanvändning (% i förhållande till L1). Sannolikheten att tillägna sig en inföddlik slutlig behärskning var högre ju tidigare startålder talarna hade och endast talare med startålder mellan 1 och 16 uppvisade inföddlikhet i både fonologi och icke-fonologi. Fler talare uppvisade inföddlikhet i icke-fonologi än i fonologi, vilket kan bero på den unika motoriska begränsning tillägnande av fonologi har.

<p>This thesis presents research investigating structural neural correlates of major depressive disorder (MDD). Although there are clear clinical differences between early- and late-onset MDD, they are still subject to the same diagnostic criteria and treatment strategy. Whether these differences translate into differences in cortical structure was examined in this study. By directly comparing early-onset (EOD) and late-onset (LOD) patients, we test whether age-of-onset results in changes in the extent or spatial pattern of cortical thinning.</p> <p>Chapter 1 provides a general background on the cerebral cortex, followed with a focus on cortical thickness. Chapter 2 presents a comprehensive review of the clinical and neurobiological literature on major depressive disorder as it pertains to age-of-onset. Three working hypotheses regarding the differences between early- and late-onset depression are presented and discussed.</p> <p>The results presented in this thesis show that there are both differences and similarities in cortical thickness between patients with EOD and LOD, with differences reflecting spatial extent, region-specificity, and magnitude of thickness differences. We confirmed the hypothesis of greater thinning in the dorsal lateral prefrontal cortex in depressed patients compared to healthy controls. We also correlated cortical thickness with clinical variables, which resulted in the finding of a positive correlation in the posterior cingulate cortex with illness severity.</p> <p>Few studies have used age-of-onset as a factor, which may account for some of the heterogeneity and inconsistent results seen in studies of MDD. We found that depression onset in early life is associated with greater disturbances in cortical thickness than LOD, possibly reflecting atypical development. These results provide novel insights into vulnerability and how development of depression is differentially affected by age.</p> / Master of Science (MSc)

This study examines the relationship between adolescent depressive symptomology and substance abuse. From a literature study six hypotheses were developed. A quantitative empirical study, undertaken in a South African high school, investigated the level of adolescent depressive symptomology and substance abuse, as well as the relationship between the two. The influence of various moderator variables was also examined. In line with most international studies, the relationship between adolescent depressive symptomology and substance abuse was found to be significant. This research has shown that adolescent depressive symptomology is significantly and positively correlated with earlier age of onset of substance abuse as well as frequency of usage. There appear to be gender differences in the way adolescents deal with their depression in terms of substance abuse. In addition, risk factors for depression and substance abuse were confirmed. Recommendations have been made based on these results. / Psychology of Education / M.Ed. (Guidance and Counselling)

This study examines the relationship between adolescent depressive symptomology and substance abuse. From a literature study six hypotheses were developed. A quantitative empirical study, undertaken in a South African high school, investigated the level of adolescent depressive symptomology and substance abuse, as well as the relationship between the two. The influence of various moderator variables was also examined. In line with most international studies, the relationship between adolescent depressive symptomology and substance abuse was found to be significant. This research has shown that adolescent depressive symptomology is significantly and positively correlated with earlier age of onset of substance abuse as well as frequency of usage. There appear to be gender differences in the way adolescents deal with their depression in terms of substance abuse. In addition, risk factors for depression and substance abuse were confirmed. Recommendations have been made based on these results. / Psychology of Education / M.Ed. (Guidance and Counselling)

Les fonctions cognitives reposent sur la communication dynamique de régions cérébrales interconnectées. Dans la maladie d’Alzheimer (MA), les travaux antérieurs suggèrent que le processus neuropathologique cible de façon précoce un ou plusieurs systèmes anatomo-fonctionnels spécifiques. La dysfonction du réseau par défaut a été objectivée de façon consistante. Cependant, ses relations avec les symptômes cliniques et avec l’atteinte des régions du lobe temporal interne qui lui sont fonctionnellement connectées restent à clarifier. L’IRM fonctionnelle de repos est une technique pertinente pour caractériser in vivo chez l’Homme la connectivité cérébrale.Par une approche des systèmes neuraux, ce travail de thèse a pour objectif de caractériser la réorganisation fonctionnelle neuronale dans la MA, ses corrélats cliniques, ainsi que l’influence de l’âge de début des symptômes. Par le recueil et l’analyse des données neuropsychologiques, en IRMf de repos et en IRM structurale, acquises chez des sujets avec des troubles de la mémoire et avec une forme mnésique légère de MA, notre travail apporte des éclairages : i) sur l’implication du réseau temporal antérieur dans la mémoire déclarative décontextualisée et ses modifications dans le cours de la MA ; ii) sur les similitudes et spécificités des systèmes anatomo-fonctionnels ciblés dans les deux formes cliniques distinctes - à début précoce et tardif - de la MA ; iii) sur la réorganisation de l’organisation topologique cérébrale dans son ensemble de ces deux formes de la maladie. / Cognitive functions rely on the dynamic interplay of connected brain regions. Previous studies suggest that in Alzheimer disease (AD), early pathological changes target one or several specific anatomo-functional networks. Dysfunction of the default mode network is a consistent finding. However, its relationship with clinical symptoms and interconnected medial temporal regions remains to be clarified. Resting state functional MRI (fMRI) is an emerging method aimed at characterizing in vivo brain connectivity in the Human.Using a neural system approach, the aim of this thesis was to characterize neuronal functional reorganization in AD, its clinical correlates, and to determine the influence of age at onset. Neuropsychological data, structural and fMRI were obtained in subjects with early memory impairment and mild “amnestic” AD. This work provides new insights into : i) the functional role of the anterior temporal network in context-free declarative memory and its changes throughout the course of AD; ii) the common and specific features in targeted anatomo-functional networks between early and late onset AD ; iii) the reorganization of whole brain topological properties in the two forms of the disease.

INTRODUÇÃO: A puberdade reuni as mudanças físicas da adolescência como o crescimento pondoestatural e a evolução da maturação sexual. Um marco importante da puberdade no sexo feminino é a menarca. Para sua ocorrência é necessária a interação de múltiplos fatores, destacando-se por sua importância a condição nutricional, da qual faz parte um teor de gordura corporal suficiente para deflagrar não só a primeira menstruação, como também a manutenção dos ciclos menstruais regulares. OBJETIVOS: Este estudo avaliou a associação entre indicadores de estado nutricional (peso, estatura, circunferência braquial e índice de massa corpórea) e de maturidade (idade e maturação sexual) para ocorrência da menarca e avaliou a percepção da imagem corporal em relação a presença ou não deste evento. MÉTODOS: Trata-se de um estudo transversal, retrospectivo, observacional, de 98 adolescentes femininas, entre 10 e 19 anos, do subdistrito do Butantã, São Paulo, Brasil, que comparou dois grupos: as que apresentaram menarca até três meses antes da pesquisa (27) e as que ainda não haviam menstruado (71). Os dados são provenientes de um banco de dados, coletados na década de 80, mediante questionários padrão, em pesquisa domiciliar e fizeram parte de estudos anteriores. A variável resposta foi a menarca e as explanatórias foram peso, estatura, circunferência braquial e índice de massa corpórea, idade, desenvolvimento mamário, impressão da estatura e impressão da condição nutricional. O processamento e análise dos dados foi realizado no Departamento Materno- Infantil da Faculdade de Saúde Pública da Universidade de São Paulo, digitados em planilha Excel® e analisados pelo programa EpiInfo versão 3.5.3 CDC e WHO Anthro versão 3.2.2 OMS. As variáveis foram descritas através de suas distribuições, frequências, médias, desvios-padrão e medianas. Testes paramétricos e não paramétricos foram usados na dependência da distribuição normal ou não das variáveis. Os indicadores que apresentaram significância estatística nos modelos univariados e apresentaram baixa correlação entre si foram testados em modelo de regressão logística para controle das variáveis de confusão. A análise da percepção da autoimagem foi realizada pela correlação entre impressão da estatura e condição nutricional com classificação do referencial gráfico. RESULTADOS: Peso, estatura, circunferência braquial, índice de massa corpórea sempre foram superiores para adolescentes com menarca em relação às sem menarca (diferença estatisticamente significativa). A primeira menstruação ocorreu mais frequentemente no estágio de desenvolvimento M4 de Tanner, com média idade de 13,26 anos. Todas as variáveis estudadas se mostraram associadas à ocorrência da menarca nas análises univariadas. No modelo multivariado, o índice de massa corpórea se revelou o principal desencadeante da menarca. Mostraram-se também associados à primeira menstruação: o desenvolvimento mamário e a idade. Foi observada uma correlação positiva entre a percepção da imagem corporal e a classificação gráfica nas meninas com e sem menarca. CONCLUSÃO: O estado nutricional, traduzido pelo índice de massa corpórea, destacou-se como principal fator desencadeante para a ocorrência da menarca, mesmo frente aos indicadores neuroendócrinos e a idade, confirmando a relevância da força do ambiente sobre a herança. Não houve diferença da percepção da imagem corporal para meninas com e sem menarca / INTRODUCTION: Puberty gathers the physical changes of adolescence such as the growth spurt and evolution of sexual maturation. An important biologic mark of puberty in females is menarche. For its occurrence an interaction of multiple factors are required, mainly the nutritional status whose body fat, depending on its amount, might trigger not only the first period, but also the maintenance of regular menstrual cycles. OBJECTIVES: This study evaluated the association between indicators of nutritional status (weight, height, arm circumference and body mass index) and maturity (age and sexual maturity) for the occurrence of menarche and it assessed the perception of body image compared with the presence or absence of this event. METHODS: It is a cross-sectional, retrospective, observational study of 98 female adolescents between 10 and 19 years old, in the sub-district of Butantan, Sao Paulo, Brazil, which compared two groups: those that had menarche up to three months before the survey (27) and those that had not menstruated (71). The data come from a database, collected in 80, through standard questionnaires on household survey. These data have already been part of previous studies. The variable response was the menarche, and the explanatory variables were weight, height, arm circumference, body mass index, age and breast development, height perception and nutritional status perception. The processing and analysis of data were performed in the Department of Maternal and Child School of Public Health, University of São Paulo, typed in Excel ® spreadsheet and analyzed by using EpiInfo version 3.5.3 CDC and WHO Anthro version 3.2.2 WHO. The variables were described according to their distributions, frequencies, means, standard deviations and medians. Parametric and non-parametric tests were used depending on the normal distribution of the variables or not. The indicators that showed statistical significance in the univariate models and showed low correlation between them were tested in a logistic regression model for the control of the confusion variables. The analysis of the perception of selfimage was performed by correlation between height and nutritional status perception with reference graph. RESULTS: Weight, height, arm circumference, body mass index were always higher for the adolescents who had menarche than for those who did not (statistically significant difference). The first period occurred more often in adolescents in stage of breast development M4, at the mean age of 13.26. In univariate analysis, all variables were associated with the occurrence of menarche. In the final model of logistic regression the body mass index was the main trigger of menarche. The other variables associated with the menarche were: breast development and age. It was a positive correlation between the perception of body image and graphical classification in girls with and without menarche. CONCLUSIONS: The nutritional status, reflected by body mass index, stood out as the main triggering factor for the occurrence of menarche, even against neuroendocrine indicators and age, confirming the relevance of the strength of the environment on the inheritance. There was no difference in the perception of body image for girls with and without menarche

INTRODUÇÃO: A puberdade reuni as mudanças físicas da adolescência como o crescimento pondoestatural e a evolução da maturação sexual. Um marco importante da puberdade no sexo feminino é a menarca. Para sua ocorrência é necessária a interação de múltiplos fatores, destacando-se por sua importância a condição nutricional, da qual faz parte um teor de gordura corporal suficiente para deflagrar não só a primeira menstruação, como também a manutenção dos ciclos menstruais regulares. OBJETIVOS: Este estudo avaliou a associação entre indicadores de estado nutricional (peso, estatura, circunferência braquial e índice de massa corpórea) e de maturidade (idade e maturação sexual) para ocorrência da menarca e avaliou a percepção da imagem corporal em relação a presença ou não deste evento. MÉTODOS: Trata-se de um estudo transversal, retrospectivo, observacional, de 98 adolescentes femininas, entre 10 e 19 anos, do subdistrito do Butantã, São Paulo, Brasil, que comparou dois grupos: as que apresentaram menarca até três meses antes da pesquisa (27) e as que ainda não haviam menstruado (71). Os dados são provenientes de um banco de dados, coletados na década de 80, mediante questionários padrão, em pesquisa domiciliar e fizeram parte de estudos anteriores. A variável resposta foi a menarca e as explanatórias foram peso, estatura, circunferência braquial e índice de massa corpórea, idade, desenvolvimento mamário, impressão da estatura e impressão da condição nutricional. O processamento e análise dos dados foi realizado no Departamento Materno- Infantil da Faculdade de Saúde Pública da Universidade de São Paulo, digitados em planilha Excel® e analisados pelo programa EpiInfo versão 3.5.3 CDC e WHO Anthro versão 3.2.2 OMS. As variáveis foram descritas através de suas distribuições, frequências, médias, desvios-padrão e medianas. Testes paramétricos e não paramétricos foram usados na dependência da distribuição normal ou não das variáveis. Os indicadores que apresentaram significância estatística nos modelos univariados e apresentaram baixa correlação entre si foram testados em modelo de regressão logística para controle das variáveis de confusão. A análise da percepção da autoimagem foi realizada pela correlação entre impressão da estatura e condição nutricional com classificação do referencial gráfico. RESULTADOS: Peso, estatura, circunferência braquial, índice de massa corpórea sempre foram superiores para adolescentes com menarca em relação às sem menarca (diferença estatisticamente significativa). A primeira menstruação ocorreu mais frequentemente no estágio de desenvolvimento M4 de Tanner, com média idade de 13,26 anos. Todas as variáveis estudadas se mostraram associadas à ocorrência da menarca nas análises univariadas. No modelo multivariado, o índice de massa corpórea se revelou o principal desencadeante da menarca. Mostraram-se também associados à primeira menstruação: o desenvolvimento mamário e a idade. Foi observada uma correlação positiva entre a percepção da imagem corporal e a classificação gráfica nas meninas com e sem menarca. CONCLUSÃO: O estado nutricional, traduzido pelo índice de massa corpórea, destacou-se como principal fator desencadeante para a ocorrência da menarca, mesmo frente aos indicadores neuroendócrinos e a idade, confirmando a relevância da força do ambiente sobre a herança. Não houve diferença da percepção da imagem corporal para meninas com e sem menarca / INTRODUCTION: Puberty gathers the physical changes of adolescence such as the growth spurt and evolution of sexual maturation. An important biologic mark of puberty in females is menarche. For its occurrence an interaction of multiple factors are required, mainly the nutritional status whose body fat, depending on its amount, might trigger not only the first period, but also the maintenance of regular menstrual cycles. OBJECTIVES: This study evaluated the association between indicators of nutritional status (weight, height, arm circumference and body mass index) and maturity (age and sexual maturity) for the occurrence of menarche and it assessed the perception of body image compared with the presence or absence of this event. METHODS: It is a cross-sectional, retrospective, observational study of 98 female adolescents between 10 and 19 years old, in the sub-district of Butantan, Sao Paulo, Brazil, which compared two groups: those that had menarche up to three months before the survey (27) and those that had not menstruated (71). The data come from a database, collected in 80, through standard questionnaires on household survey. These data have already been part of previous studies. The variable response was the menarche, and the explanatory variables were weight, height, arm circumference, body mass index, age and breast development, height perception and nutritional status perception. The processing and analysis of data were performed in the Department of Maternal and Child School of Public Health, University of São Paulo, typed in Excel ® spreadsheet and analyzed by using EpiInfo version 3.5.3 CDC and WHO Anthro version 3.2.2 WHO. The variables were described according to their distributions, frequencies, means, standard deviations and medians. Parametric and non-parametric tests were used depending on the normal distribution of the variables or not. The indicators that showed statistical significance in the univariate models and showed low correlation between them were tested in a logistic regression model for the control of the confusion variables. The analysis of the perception of selfimage was performed by correlation between height and nutritional status perception with reference graph. RESULTS: Weight, height, arm circumference, body mass index were always higher for the adolescents who had menarche than for those who did not (statistically significant difference). The first period occurred more often in adolescents in stage of breast development M4, at the mean age of 13.26. In univariate analysis, all variables were associated with the occurrence of menarche. In the final model of logistic regression the body mass index was the main trigger of menarche. The other variables associated with the menarche were: breast development and age. It was a positive correlation between the perception of body image and graphical classification in girls with and without menarche. CONCLUSIONS: The nutritional status, reflected by body mass index, stood out as the main triggering factor for the occurrence of menarche, even against neuroendocrine indicators and age, confirming the relevance of the strength of the environment on the inheritance. There was no difference in the perception of body image for girls with and without menarche

Τα δημογραφικά χαρακτηριστικά και η συμπτωματολογία και της παρανοειδούς μορφής σχιζοφρένειας πρώιμης και όψιμης έναρξης μελετήθηκαν σε 88 ασθενείς, που νοσηλεύθηκαν στην Ψυχιατρική Κλινική του Πανεπιστημίου Πατρών, από 15-3-2005 έως 7-5-2008. Εξ’ αυτών, 60, 46 άνδρες και 14 γυναίκες, ενεφάνιζαν πρώιμη έναρξη της νόσου, πριν από την ηλικία των 30 ετών, ενώ 21, 8 άνδρες και 13 γυναίκες, ασθένησαν όψιμα, με έναρξη νόσου σε ηλικία ≥35 ετών. Συνεκρίθησαν τα δημογραφικά στοιχεία, η συχνότητα κατάχρησης ή εξάρτησης τον καπνό, οινόπνευμα και κάνναβη, τα στοιχεία προνοσηρών διαταραχών προσωπικότητας, ο αριθμός και ο τύπος των προδρόμων συμπτωμάτων, η διάρκεια της πρόδρομης φάσης και η συμπτωματολογία της ενεργού φάσης μεταξύ των ασθενών πρώιμης και όψιμης έναρξης, συνολικά και χωριστά για τα δύο φύλα, καθώς και μεταξύ ανδρών και γυναικών, στις δύο ηλικιακές ομάδες. Οι κλίμακες που εφαρμόσθηκαν ήταν οι SCID-I/P, PANSS, Calgary Depression Scale, SCID-II, καθώς και κλινική συνέντευξη για τα πρόδρομα συμπτώματα. Τα στοιχεία αναλύθηκαν με τις στατιστικές δοκιμασίες Wilcoxon rank-sum και χ2. Οι ασθενείς πρώιμης έναρξης, και ιδιαίτερα οι άνδρες, είχαν στατιστικώς σημαντικά μεγαλύτερη πιθανότητα να έχουν γεννηθεί σε αστική περιοχή σε σχέση με τους ασθενείς όψιμης έναρξης. Οι γυναίκες όψιμης έναρξης είχαν το μεγαλύτερο ποσοστό έγγαμης συμβίωσης από όλες τις άλλες ομάδες. Δεν παρατηρήθηκε στατιστικώς σημαντική διαφορά στη χρήση καπνού, οινοπνεύματος και κάνναβης μεταξύ των ομάδων πρώιμης και όψιμης έναρξης, συνολικά ή χωριστά στα δύο φύλα. Στην ομάδα πρώιμης έναρξης, οι άνδρες παρουσίαζαν σε μεγαλύτερη συχνότητα χρήση αλκοόλ και κάνναβης σε σχέση με τις γυναίκες. Παρομοίως, οι άνδρες όψιμης έναρξης κάπνιζαν και έτειναν να χρησιμοποιούν κάνναβη σε μεγαλύτερο ποσοστό από τις γυναίκες. Στην προνοσηρή περίοδο, οι πρώιμης έναρξης ασθενείς έχουν σημαντικά περισσότερα στοιχεία αποφευκτικής διαταραχής προσωπικότητας σε σχέση με τους όψιμης έναρξης. Αυτό το εύρημα πλησιάζει τη στατιστική σημαντικότητα και στο δείγμα των γυναικών. Οι ασθενείς όψιμης έναρξης, στο συνολικό δείγμα και στο δείγμα των ανδρών, εμφανίζουν στατιστικώς σημαντικά περισσότερα στοιχεία παθητικο-επιθετικής διαταραχής προσωπικότητας σε σχέση με τους ασθενείς πρώιμης έναρξης. Στην ομάδα με την πρώιμη έναρξη, οι άνδρες είχαν περισσότερα στοιχεία σχιζότυπης και παρανοειδούς διαταραχής προσωπικότητας από τις γυναίκες, ενώ οι τελευταίες είχαν περισσότερα στοιχεία καταθλιπτικής διαταραχής προσωπικότητας. Στους ασθενείς όψιμης έναρξης, οι άνδρες είχαν περισσότερα στοιχεία ιστριονικής, ναρκισσιστικής και αντικοινωνικής διαταραχής από τις γυναίκες. Στην πρόδρομη φάση, οι ασθενείς πρώιμης έναρξης παρουσιάζουν στατιστικώς σημαντικά μεγαλύτερο αριθμό αρνητικών συμπτωμάτων, στο συνολικό δείγμα και στο δείγμα των ανδρών. Στο συνολικό δείγμα, τα συμπτώματα της εκσεσημασμένης κοινωνικής απομόνωσης και της έκπτωσης της συγκέντρωσης παρατηρούνται σε στατιστικώς σημαντικά μεγαλύτερο ποσοστό στην ομάδα με την πρώιμη έναρξη σε σχέση με την ομάδα όψιμης έναρξης. Στους ασθενείς που νόσησαν πρώιμα, οι γυναίκες είχαν μικρότερη διάρκεια πρόδρομης περιόδου από τους άνδρες. Κατά την ενεργό φάση, η ομάδα πρώιμης έναρξης εμφάνιζε βαρύτερη συνολική αρνητική συμπτωματολογία, καθώς και βαρύτερα τα συμπτώματα της έλλειψης αυθορμητισμού και των διαταραχών της βούλησης. Αντίθετα, οι ασθενείς όψιμης έναρξης έτειναν νε έχουν βαρύτερο το σύμπτωμα της καχυποψίας/ιδεών δίωξης. Στο δείγμα των ανδρών, οι ασθενείς πρώιμης έναρξης είχαν στατιστικώς σημαντικά βαρύτερη συνολική αρνητική συμπτωματολογία, συναισθηματική αμβλύτητα και έλλειψη αυθορμητισμού. Στο δείγμα των γυναικών δεν ανευρέθησαν στατιστικώς σημαντικές διαφορές. Στους ασθενείς όψιμης έναρξης, οι άνδρες εμφάνιζαν σημαντικά βαρύτερες παραληρητικές ιδέες σε σχέση με τις γυναίκες. Ως προς την καταθλιπτική συμπτωματολογία, δεν παρατηρήθηκαν διαφορές μεταξύ των ομάδων. Συνολικά τα παραπάνω ευρήματα υποδεικνύουν την τροποποιητική επίδραση του φύλου και της ηλικίας έναρξης στην κλινική εμφάνιση της παρανοϊκής μορφής σχιζοφρένειας, κατά την προνοσηρή περίοδο, πρόδρομη και ενεργό φάση, πιθανόν ως αποτέλεσμα των διεργασιών ανάπτυξης και ωρίμανσης του εγκεφάλου με την πάροδο της ηλικίας, στα δύο φύλα. / The demographic features and symptomatology of young and late onset paranoid schizophrenia were studied in a sample of 88 patients who were consecutively hospitalized in the Psychiatric Department of the University Hospital of Patras, from 3-15-2005 to 5-7-2008. The sample consisted of 60 patients, 46 men and 14 women, with young onset paranoid schizophrenia, before the age of 30, and 21 late onset patients, 8 men and 13 women, with onset of the illness after the age of 35 years old. Demographic features, rates of smoking and alcohol and cannabis use, premorbid personality disorder features, the number and type of prodromal symptoms, the duration of the prodromal period and the symptomatologies of the active phase were compared between young and late onset groups, in the total sample and separately for the two sexes, and between the two sexes in each age group. SCID-I/P, PANSS, Calgary Depression Scale, SCID-II, and a clinical interview for the prodromal symptoms were applied. Statistical analysis was performed by applying the Wilcoxon rank-sum and chi-square tests. Young onset patients, particularly men, were more likely to have been born in urban regions, compared with late onset patients. Late onset women were most frequently married, compared with all other groups. There was not any significant difference regarding use of nicotine, alcohol or cannabis between young and late onset patients. In the young onset group, men more frequently used alcohol and cannabis than women. Similarly, late onset men smoked and tended to use cannabis more often than late onset women. In the premorbid period, young onset patients have significantly more traits of avoidant personality disorder compared with late onset patients. This finding tended to be significant in the female sample, as well. Late onset patients had significantly more traits of passive-aggressive personality disorder than young onset patients, in the total and male sample. In the young onset group, men had significantly more traits of paranoid and schizotypal personality disorder than women, whereas women had more traits of the depressive personality disorder. In the late onset group, men had more histrionic, narcissistic and antisocial traits than women. In the prodromal phase, young onset patients present with significantly more negative prodromal symptoms, in the total and the male sample. In the total sample, marked isolation and impairment of concentration are observed at a significantly higher rate in the young onset group, than in late onset patients. Also, in the young onset group, women had significantly shorter duration of prodromal period than men. During the active phase, young onset patients had significantly heavier total score of negative symptomatology, heavier lack of spontaneity and heavier disturbances of volition. On the other hand, late onset patients tended to suffer from heavier suspiciousness/ideas of persecution. In the male sample, young onset patients had heavier total negative symptomatology, blunted affect and lack of spontaneity. There were not any significant differences in the female sample. In the late onset group, men had heavier delusions than women. There was not any significant difference regarding depressive symptoms among the groups. Our findings indicate the modulatory effect of age of onset and sex on the clinical presentation of paranoid schizophrenia, in the premorbid period, prodromal and active phases, possibly following the developmental and maturational procedures that take place in the brain, throughout the life span, in the two sexes.