The main aim of the thesis was to measure antidepressant (AD) non-compliance, to determine which factors are closely associated with AD non-compliance and the consequences of prolonged AD non-compliance in the private health sector of South Africa. The empirical study followed an observational, prospective, cohort study using longitudinal medicine claims data provided by a nationally representative Pharmaceutical Benefit Management company (PBM) from 1 January 2006 to 31 December 2011. Failure to respond to AD treatment and achieving remission has severe neurobiological and clinical consequences. The clinical consequences include increased social and functional impairment, higher risk for recurrence and relapse of a depressive episode, a weak treatment outcome, significant increase in treatment cost, over-utilization of health care systems, and ultimately an increased suicide risk. However, the neurobiological consequences are much more far reaching. One of the more serious yet under-recognized neurobiological complications of AD non-compliance is the development of antidepressant discontinuation syndrome (ADS), which is the result of non-compliance or the abrupt discontinuation of AD treatment. Altered serotonergic dysfunction appears central to ADS so that how an antidepressant targets serotonin will determine its relative risk for inducing ADS and thereby affect later treatment outcome. Low ADS risk with agomelatine versus other antidepressants can be ascribed to its unique pharmacokinetic characteristics as well as its distinctive actions on serotonin, including melatonergic, monoaminergic and glutamatergic-nitrergic systems. After the first four months only 34% (n=12 397) of patients were compliant. What’s more a statistically significant association was found between active ingredient consumed and compliance (p < 0.0001). Only 26.2% of patients who received amitriptyline-containing products were complaint compared to 38.8% and 38.7% in the cases of venlafaxine and duloxetine, respectively. The current study found that females have a significantly higher prevalence of MDD and HIV/AIDS when compared to males. The co-morbidity between HIV/AIDS and major depressive disorder (MDD) had a significant effect on AD treatment compliance as patients diagnosed with both HIV/AIDS and MDD (74.43. ± 32.03, 95%Cl: 71.51-77.34) displayed a lower compliance vs. MDD patients (80.94% ± 29.44, 95%Cl: 80.56-81.33). Noteworthy, observations were that 75% (p < 0.0217; Cramer’s V = 0.0388) of venlafaxine and 28.6% (p < 0.0197; Cramer’s V = -0.0705) of the paroxetine items were compliant in patients diagnosed with both HIV/AIDS and MDD. The overall compliance (35.19% acceptable compliance; n = 42 869) of patients taking both ADs and GDs was weak. In the group receiving both AD and GDs, an increased AD treatment period was associated with a significant increase (p < 0.0001) in AD compliance (406.60 days; 95%Cl: 403.20 – 409.90 vs. 252.70 days; 95%Cl: 250.20 – 255.20). In this cohort amitriptyline (29.57%), mirtazapine (31.36%) and fluoxetine (32.29%) were associated with the lowest levels of compliance, while duloxetine (40.67%) was found to have the highest compliance. Lastly, ADs with highest non-compliance were associated with an increase use in GDs. Alprazolam (n = 10 201) and zolpidem (n = 9 312) were the most frequently dispensed GDs in combination with AD treatment. In conclusion the current study confirms that AD non-compliance is as big an obstacle in developing countries as it is in developed countries. Antidepressant treatment non-compliance has far reaching consequences especially with the development of ADS which further complicates MDD and might be a precursor for the development of TRD. Several factors were found to be closely associated with AD treatment non-compliance which include; pharmacological class of AD, gender, chronic co-morbid illnesses and a short treatment period. / PhD (Pharmacy Practice), North-West University, Potchefstroom Campus, 2015

The main aim of the thesis was to measure antidepressant (AD) non-compliance, to determine which factors are closely associated with AD non-compliance and the consequences of prolonged AD non-compliance in the private health sector of South Africa. The empirical study followed an observational, prospective, cohort study using longitudinal medicine claims data provided by a nationally representative Pharmaceutical Benefit Management company (PBM) from 1 January 2006 to 31 December 2011. Failure to respond to AD treatment and achieving remission has severe neurobiological and clinical consequences. The clinical consequences include increased social and functional impairment, higher risk for recurrence and relapse of a depressive episode, a weak treatment outcome, significant increase in treatment cost, over-utilization of health care systems, and ultimately an increased suicide risk. However, the neurobiological consequences are much more far reaching. One of the more serious yet under-recognized neurobiological complications of AD non-compliance is the development of antidepressant discontinuation syndrome (ADS), which is the result of non-compliance or the abrupt discontinuation of AD treatment. Altered serotonergic dysfunction appears central to ADS so that how an antidepressant targets serotonin will determine its relative risk for inducing ADS and thereby affect later treatment outcome. Low ADS risk with agomelatine versus other antidepressants can be ascribed to its unique pharmacokinetic characteristics as well as its distinctive actions on serotonin, including melatonergic, monoaminergic and glutamatergic-nitrergic systems. After the first four months only 34% (n=12 397) of patients were compliant. What’s more a statistically significant association was found between active ingredient consumed and compliance (p < 0.0001). Only 26.2% of patients who received amitriptyline-containing products were complaint compared to 38.8% and 38.7% in the cases of venlafaxine and duloxetine, respectively. The current study found that females have a significantly higher prevalence of MDD and HIV/AIDS when compared to males. The co-morbidity between HIV/AIDS and major depressive disorder (MDD) had a significant effect on AD treatment compliance as patients diagnosed with both HIV/AIDS and MDD (74.43. ± 32.03, 95%Cl: 71.51-77.34) displayed a lower compliance vs. MDD patients (80.94% ± 29.44, 95%Cl: 80.56-81.33). Noteworthy, observations were that 75% (p < 0.0217; Cramer’s V = 0.0388) of venlafaxine and 28.6% (p < 0.0197; Cramer’s V = -0.0705) of the paroxetine items were compliant in patients diagnosed with both HIV/AIDS and MDD. The overall compliance (35.19% acceptable compliance; n = 42 869) of patients taking both ADs and GDs was weak. In the group receiving both AD and GDs, an increased AD treatment period was associated with a significant increase (p < 0.0001) in AD compliance (406.60 days; 95%Cl: 403.20 – 409.90 vs. 252.70 days; 95%Cl: 250.20 – 255.20). In this cohort amitriptyline (29.57%), mirtazapine (31.36%) and fluoxetine (32.29%) were associated with the lowest levels of compliance, while duloxetine (40.67%) was found to have the highest compliance. Lastly, ADs with highest non-compliance were associated with an increase use in GDs. Alprazolam (n = 10 201) and zolpidem (n = 9 312) were the most frequently dispensed GDs in combination with AD treatment. In conclusion the current study confirms that AD non-compliance is as big an obstacle in developing countries as it is in developed countries. Antidepressant treatment non-compliance has far reaching consequences especially with the development of ADS which further complicates MDD and might be a precursor for the development of TRD. Several factors were found to be closely associated with AD treatment non-compliance which include; pharmacological class of AD, gender, chronic co-morbid illnesses and a short treatment period. / PhD (Pharmacy Practice), North-West University, Potchefstroom Campus, 2015

Patients with MDD demonstrate impairments in various components of affective processing, which are believed to persist in the remitted phase of the illness and are believed to underlie the vulnerability for future relapse. Despite advances in neuropsychiatry, the neuroanatomical site of action of various treatment modalities remains unclear, leaving clinicians without an algorithm to guide optimal treatment selection for individual patients. This thesis sought to characterize differences in brain activation during affective processing between MDD treatment responders (RS) and non-responders (NR) by combining clinical and neuroimaging variables in a repeat-measure functional magnetic resonance imaging (fMRI) investigation. We induced increases in positive and negative affect using visual stimuli under fMRI conditions in 21 MDD subjects and 18 healthy controls (HC). Based on previous neuroimaging investigations and preclinical animal data, we hypothesized that increased activation of the amygdala and the pregenual cingulate during negative affect induction (NAI), and decreased activity of the ventral striatum during positive affect induction (PAI), would differentiate ultimate NR from RS. Following the first scan, treatment with fluoxetine and olanzapine was initiated in the MDD group, with follow-up scans at one- and six-weeks thereafter. We hypothesized that decreases in depressive symptoms would be associated with decreased activation of the ventromedial prefrontal cortex (PFC) and amygdala during NAI and increased activation of the hippocampus during PAI. Eleven MDD subjects met criteria for clinical remission at study endpoint. Based on trait differences between MDD and HC, we hypothesized that differences observed during NAI would be limited to brain regions involved in regulation of the affective state, including the dorsolateral PFC and the anterior midcingulate cortex. The results of the analyses confirmed the a-prior hypotheses and additionally demonstrated differential activation of the insular, medial temporal, and premotor cortex during repeat PAI and NAI between HC, RS, and NR. These findings provide: i) a neuroanatomical target of successful antidepressant therapy during PAI/NAI; ii) a differential effect of depressive symptoms and dispositional affect on brain activation during PAI/NAI; and iii) an a-prior method to differentiate RS from NR, and iv) demonstrate the need for additional treatment to prevent relapse in the remitted state.

Objectifs: Malgré que les patients souffrant de dépression majeure (DM) rapportent souvent des symptômes douloureux, la relation entre la douleur et la dépression n’est pas encore claire. Ce n’est que récemment que des études employant des paradigmes de sommation temporelle ont pu offrir une explication préliminaire de la cooccurrence de la douleur et de la dépression. Notre étude vise à évaluer la contribution des procédés spinaux et surpraspinaux dans la sensibilisation de la douleur dans la DM en utilisant un paradigme de sommation temporelle. Participants : Treize sujets sains et quatorze patients souffrant de DM ont été inclues dans l’analyse finale. Méthodes : Pour induire une sommation temporelle, nous avons utilisé des stimulations intermittentes du nerf sural de basses et hautes fréquences. La sensibilisation spinale de la douleur a été quantifiée en mesurant la variation de l’amplitude du réflex de retrait nociceptif (NFR) entre les deux conditions de stimulations, ainsi que la sensibilisation supraspinale de la douleur a été obtenue en mesurant le changement dans l’appréciation verbale de la douleur entre ces deux conditions. Résultats : Nous avons observé une sensibilisation plus élevée de la réponse NFR chez les patients dépressifs durant la condition de stimulation à haute fréquence, un effet qui n’a pas été reflété par une sensibilisation amplifiée des appréciations subjectives de la douleur durant l’expérience. Néanmoins, nous avons observé une association entre la sensibilisation spinale et les symptômes somatiques douloureux chez les patients DM. Conclusion : Ces résultats suggèrent une sensibilisation spinale amplifiée dans la DM, ce qui pourrait expliquer la prévalence élevée des symptômes somatiques douloureux chez ces patients. / Objectives: Although patients suffering from major depressive disorder (MDD) often complain from painful symptoms, the relationship between pain and depression has yet to be clearly characterized. Only recently have studies employing temporal summation paradigms offered some preliminary insight into the co-occurrence of pain and depression. This study sets out to evaluate the contribution of spinal and supraspinal processes in pain sensitization in MDD using a temporal summation paradigm. Subjects: Thirteen healthy controls and fourteen MDD patients were included in the final analysis. Methods: To induce temporal summation, we used low- and high-frequency intermittent stimulations of the sural nerve. Spinal pain sensitization was quantified by measuring the change in the amplitude of the nociceptive-specific flexion reflex (NFR) response, and supraspinal pain sensitization was obtained by measuring change in subjective pain rating, from the low- to high-frequency stimulation condition. Results: We found an increased sensitization in the NFR response in MDD patients in the high-frequency condition, which did not translate into an increased amplification of their subjective responses during testing. However, we found a positive association between spinal sensitization and painful somatic symptoms in MDD patients. Conclusion: Together, these results suggest increased spinal pain sensitization in MDD, which might explain the high prevalence of painful somatic symptoms in these patients.

Introduction : L'électroconvulsivothérapie (ECT) est un traitement non pharmacologique du trouble dépressif résistant. Bien que son efficacité ait été démontrée dans cette indication, les mécanismes cérébraux qui sous-tendent ce processus restent très imprécis. Il n'existe actuellement pas de travail étudiant l'effet d'une ECT efficace au niveau des modifications structurofonctionnelles cérébrales. Il semble primordial de poursuivre l'étude des corrélats neuroanatomiques précoces et plus tardifs sous tendant les processus neurofonctionnels responsables de l'amélioration de la clinique. Méthodes : Il s'agit d'une étude mono centrique menée sur le CHU de Toulouse. Chez des patients présentant un trouble dépressif résistant, des évaluations cliniques et en IRM multimodale sont réalisées à 4 temps. La 1ère évaluation a lieu avant le début de la cure, la 2ème après une 1ère ECT, la 3ème après une 1ère ECT efficace et la 4ème après rémission.Résultats: Concernant le volume de l'hippocampe et de l'amygdale à la première visite n'était pas diffèrent du volume à la troisième visite (t(135) = .329, p = .94). Au contraire, il y avait une différence significatif entre le volume de deux structures entre la première et la quatrième visite (t(135) = -2.47, p = .039) et entre la troisième et la quatrième visite (t(135) = -3.51, p = .002). Concernant la diffusivité moyenne en tant que l'effet des visites tend vers la significativité pour la DM (F(2,136) = 2.67, p = .072). En IRM resting state, il existe une hypoconnectivité précoce entre (i) l'hippocampe Droit et le cortex Cingulaire antérieur dorsal (t = -6.20 ; pFDR : 0.0123) ; (ii) l'hippocampe Droit et le noyaux caudé gauche ( t = -7.69 ; pFDR : 0.0035) et (iii) le vermis cervelet et le precuneus (t = -5.93 p FDR : 0.0363). Il existe une hyperconnectivité entre V4 et V1 entre (i) le cortex orbito frontal médian droit et le gyrus occipital médian (t = 6.58 ; p FDR : 0.0146) et (ii) le gyrus frontal inférieur droit et le cortex fronto median gauche (t = 6.83 ; pFDR : 0.0104). Il existe une diminution significative des symptomes de depression entre la V4 et la V1 à l'échelle d'Hamilton (V4: 3,08 ET : 1,62 ; V1 : 23,17 ET : 3,21 ; p <0.001).Conclusion : Il semble exister des modifications structuro-fonctionnelle à l'issu de la cure d'ECT sans modifications structurelles et micro structurelles précoces. / Background: Electroconvulsive Therapy (ECT) is a non-pharmacological treatment of resistant depressive disorder. Although its efficacy has been demonstrated in this indication, the brain mechanisms underlying this process remain very imprecise. There is currently no work studying the effect of one effective ECT on cerebral structural changes. It seems essential to continue the study of the early and late neuroanatomical correlates underlying neurofunctional processes responsible for improving the clinic. Methods: This is a mono-centric study conducted on the Toulouse University Hospital. In patients with resistant depressive disorder, clinical and multimodal MRI assessments are performed at 4-step intervals. The first evaluation takes place before the beginning of the treatment, the 2nd after a 1st ECT, the 3rd after a 1st effective ECT and the 4th after remission. Results: Regarding the volume of the hippocampus and amygdala at the first visit was not different from the volume at the third visit (t (135) = .329, p = .94). On the contrary, there was a significant difference between the volume of two structures between the first and the fourth visit (t (135) = -2.47, p = .039) and between the third and fourth visits (t (135) = -3.51, p = .002). For mean diffusivity, the effect of visits showed a trend toward significance for MD (F (2.136) = 2.67, p = .072). In the MRI resting state, there is early hypoconnectivity between (i) the right hippocampus and the dorsal anterior cingulate cortex (t = -6.20, pFDR: 0.0123); (ii) right hippocampus and left caudate nucleus (t = -7.69, pFDR: 0.0035) and (iii) vermis cerebellum and precuneus (t = -5.93 p FDR: 0.0363). There is hyperconnectivity between V4 and V1 between (i) the right medial orbit frontal cortex and the medial occipital gyrus (t = 6.58; p FDR: 0.0146) and (ii) the right inferior frontal gyrus and left fronto medial cortex (t = 6.83, pFDR: 0.0104). There is a significant decrease in the symptoms of depression between V4 and V1 at the Hamilton scale (V4: 3.08 AND: 1.62, V1: 23.17 AND: 3.21, p <0.001). Conclusion: There appears to be structural-functional changes at the end of the ECT course. However, we do not find early structural and micro structural changes.

O HCL-32 é um questionário de 32 itens, de auto-aplicação, onde os sintomas são avaliados através de respostas do tipo \"sim\" (presente ou típico) ou \"não\" (não está presente ou atípico). Além disso, o HCL-32 tem 8 seções para avaliar a gravidade e o impacto dos sintomas sobre os diferentes aspectos da vida do paciente. A pontuação é obtida pela soma das respostas positivas para os 32 itens sobre hipomania. A versão original do HCL-32 foi traduzido e adaptado para o português brasileiro. A primeira versão do HCL-32 foi traduzida por nós, revisados por especialistas em transtornos de humor, bem como por um professor de português brasileiro. Foi então retro-traduzida por um professor de inglês americano. Dos indivíduos inicialmente selecionados, foram excluídos 27, 11 devido à presença de comorbidades com abuso de substância, e 16 devido à incapacidade de preencher corretamente o questionário. Assim, nossa amostra final ficou composta por 81 pacientes com TB (37 TBI; 44TBII), 42 com TDM, e 362 sujeitos de uma população não clínica. A consistência interna foi elevada, com um alfa de Cronbach de 0,793 para todo o HCL-32 VB, indicando que os itens do questionário são suficientemente homogêneos. Indivíduos com TB tiveram a maior pontuação no HCL-32 VB. A média de respostas afirmativas foi significativamente diferente de acordo com o diagnóstico. Analisamos a capacidade em diferenciar os diagnósticos através da curva ROC. A área sob a curva foi de 0.702, indicando a boa capacidade da escala para distinguir entre diagnósticos. A melhor combinação de sensibilidade (0.75) e especificidade (0.58) ocorreu com uma pontuação acima de 18. Esta pontuação distinguiu entre pacientes com TB e TDM. Para comparar as propriedades discriminativas do HCL-32 VB e MDQ VB, foram calculadas a sensibilidade e especificidade de ambos os questionários. A HCL-32 VB teve uma sensibilidade de 0.75 e especificidade de 0.58. O MDQ teve sensibilidade de 0.70 e especificidade de 0.58. Assim, a HCL-32 BV apresentou maior sensibilidade, mas a mesma especificidade que o MDQ. A análise fatorial resultou em nove fatores com autovalores > 1, explicando 53,1% da variância total. De acordo com o teste Scree, foi preferida uma solução com três fatores. O primeiro fator, com autovalor de 4,90, explicou 15,3% da variância e foi composto por 10 itens. Essa subescala reflete questões relacionadas com ativação/elação. O segundo fator, com autovalor de 3,48 (10,88% da variância), composto por 11 itens e sua estrutura inclui questões relacionadas com \"irritabilidade / comportamento de risco\". O terceiro fator, com autovalor de 1,56 (4,87% da variância), ficou composto por cinco itens e sua estrutura reflete questões relacionadas com \"desinibição / ativação sexual. Os parâmetros psicométricos de HCL-32 VB sugerem que é um instrumento útil para a detecção de hipomania em pacientes com transtornos de humor. O HCL-32 VB é um questionário rápido de auto-aplicação e de fácil interpretação / The HCL-32 is a 32-item self-administered questionnaire where symptoms are assessed through yes (present or typical) or no (not present or untypical) answers. In addition, the HCL-32 has 8 other sections evaluating the severity and impact of the symptoms on different aspects of patient\'s life. The score is obtained by adding the positive responses to the 32 symptoms of hypomania. The original version of the HCL-32 was translated and adapted to Brazilian Portuguese .The first draft of the Brazilian version was translated by us, reviewed by experts in mood disorders, as well as by a Brazilian-Portuguese teacher. It was then back-translated by an English (American) teacher. Of the individuals initially enrolled, 27 individuals were excluded; 11 due to the presence of comorbidities with substance abuse, and 16 due to inability to properly fill the questionnaires. Accordingly, our final sample comprised of 81 patients with BP (37 BPI; 44 BPII), 42 with MDD, and 362 subjects from a nonclinical population. Internal consistency was high, with a Cronbach\'s alpha of 0.793 for the entire HCL-32 BV, indicating that the items of the questionnaire are sufficiently homogeneous. Individuals with BP had the highest HCL-32 BV scores. The mean number of affirmative responses to the list of symptoms was significantly different according to diagnosis. We analyzed the scale\'s discrimination for BP trough the ROC curve. The area under the curve was 0.702 indicating the good ability of this screening scale. The best combination of sensitivity (0.75) and specificity (0.58) happened with a score above 18. This score discriminates between BP patients and MDD. To compare the discriminative properties of HCL-32 BV and MDQ, we calculated the sensitivity and specificity of both questionnaires. The HCL-32 BV had a sensitivity of 0.75 and specificity of 0.58. The MDQ had sensitivity of 0.70 and specificity of 0.58. Hence, the HCL-32 BV showed higher sensitivity but the same specificity than the MDQ. The factor analysis resulted in 9 factors with eigenvalues > 1, explaining 53.1% of the total variance. According to the Scree test, a 3-factor solution was preferred. The first factor, with an Eigenvalue of 4.90, explained 15.3% of the variance and comprised 10 items . This subscales structure reflects questions related to active/elated symptoms. The second factor, with an Eigenvalue of 3.48 (10.88% of the variance), comprised 11 items and its structure includes questions associated with irritable/risk-taking items. The third factor, with an Eigenvalue of 1.56 (4.87% of variance), comprised 5 itens and its structure reflect questions related to disinhibition/activation sexual. The psychometric parameters of HCL-32 BV suggest it as a useful instrument for the detection of hypomania in patients with mood disorders. HCL-32 BV is a brief, self-administered questionnaire of easy application and interpretation

Made available in DSpace on 2016-03-22T17:26:38Z (GMT). No. of bitstreams: 1 Tese F_bio Coelho.pdf: 893978 bytes, checksum: 2b754c3c09e0ebf28b38d7a14eb830f0 (MD5) Previous issue date: 2012-01-16 / Objective: To describe the prevalence of major depressive disorder (MDD) during pregnancy in teenager mothers, and assess its association with sociodemographic characteristics, obstetric history and psychosocial variables. Methods: A cross-sectional study with a sample of pregnant teenagers enrolled in the national public health system in the urban area of Pelotas, southern Brazil. Sample size was estimated in 871 participants. MDD was assessed with the Mini International Neuropsychiatric Interview; the Abuse Assessment Screen was used to identify physical abuse within the last 12 months and during pregnancy; social support was assessed with the Medical Outcomes Survey Social Support Scale. Results: Forty three (4.94%) refused to participate, resulting in 828 participants. Prevalence of MDD was 17.8%; violence within the last 12 months was reported by 9.2%, while 5.8% had suffering violence during pregnancy; mean (SD) overall social support score was 87.40 (±11.75). After adjustment, we found the highest prevalence ratios of MDD in adolescents with less than 8 years of education, followed by those with previous episodes of MDD and in those with lower overall social support. Conclusion: MDD is a relatively common condition in pregnant teenagers and seems to be more frequent in a group of young mothers who were both socioeconomic and psychosocially underprivileged / Objetivo: Descrever a prevalência de transtorno depressivo maior (TDM) durante a gestação em adolescentes e verificar sua associação com características sócio-demográficas obstétricas e psicossociais. Método: Estudo transversal com uma amostra de gestantes adolescentes que recebem acompanhamento pré-natal pelo sistema único de saúde na zona urbana da cidade de Pelotas, RS. O tamanho estimado da amostra foi de 871 participantes. TDM foi avaliado com o Mini International Neuropsychiatric Interview; o Abuse Assessment Screen foi utilizado para identificar abuso físico no ultimo ano e durante a atual gestação; o suporte social foi mensurado com o Medical Outcomes Survey Social Support Scale. Resultados: Quarenta e três (4.94%) recusaram-se a participar, resultando em 828 participantes. A prevalência de TDM foi de 17.8%; violência nos últimos 12 meses foi identificada em 9.2%, enquanto 5.8% sofreram violência durante a gestação; a média (DP) geral na escala de suporte social foi de 87.40 (±11.75). Após ajuste, maiores razões de prevalência de TDM foram encontradas em adolescentes com menos de 8 anos de estudo, seguidas por aquelas com episódios anteriores de depressão e por aquelas com menor suporte social. Conclusão: TDM é uma condição comum in gestantes adolescentes, sendo mais frequente em um grupo de mães desprivilegiadas do ponto de vista sócio-econômico e psicossocial

O Transtorno Depressivo Maior (TDM) é uma condição neuropsiquiátrica que resulta em um substancial sofrimento pessoal, incapacidade e custos sociais. Devido à inacessibilidade ao encéfalo humano por questões práticas, éticas e às limitações encontradas pelo uso de modelos animais, o desenvolvimento de modelos in vitro acurados torna-se fundamental para o estudo desta doença. Neste aspecto, o surgimento da tecnologia de células-tronco pluripotentes induzidas humanas (hiPSCs) apresenta-se como uma importante ferramenta, uma vez que permite a recapitulação da diversidade genética dos pacientes e possibilita a produção de tipos celulares de interesse para o estudo da doença, como neurônios e glia. Entretanto, até o momento, não há registros da produção de modelos in vitro a partir de hiPSCs de pacientes com TDM. Visando preencher esta lacuna, o presente estudo teve por objetivo a produção e caracterização de dois tipos de modelos in vitro a partir de hiPSCs de pacientes com TDM: neurônios serotoninérgicos, uma cultura celular em monocamada, e organóides cerebrais, uma cultura celular em suspensão. 5 linhagens de hiPSCs de pacientes foram diferenciadas em neurônios com sucesso e no ensaio de imunocitoquímica, expressaram os marcadores 5-HT (serotonina), T5-HT (transportador de serotonina), nestina (presente em diferentes tipos de células neuronais) e Tuj1 (proteína do citoesqueleto, neurônio-específica), confirmando o fenótipo de neurônios serotoninérgicos. As céluas diferenciadas obtiveram também resultados positivos nos testes de imageamento de cálcio e de medidas da alteração no potencial de membrana, indicando que os neurônios diferenciados eram fisiologicamente funcionais. De 5 linhagens de hiPSCs (sendo uma controle e as outras 4 de pacientes com TDM), somente 1 linhagem sobreviveu ao processo de diferenciação, originando organóides cerebrais e apresentou expressão dos marcadores Sox2 (progenitoras neurais) e Tuj1 (neurônios maduros), indicando ainda uma estruturação correta da citoarquitetura, com as progenitoras localizadas mais internamente, na zona ventricular, ao redor dos lúmens preenchidos com líquido e com os neurônios maduros localizados na placa cortical, região mais externa dos agregados celulares. Apesar de o processo de produção dos organóides cerebrais necessitar de aperfeiçoamento e melhor padronização, a produção destes dois tipos de modelos in vitro, feitos a partir de hiPSCs de pacientes com TDM configura-se como um importante passo para a futura redução do uso de modelos animais em pesquisa, elucidação de mecanismos subjacentes à doença, identificação de biomarcadores diagnósticos e triagem de fármacos de maneira personalizada, visando permitir tratamentos mais baratos, adequados e eficientes para o TDM / Major Depressive Disorder (MDD) is a neuropsychiatric condition that results in substantial personal distress, disability, and social costs. The inaccessibility to the human brain due to practical and ethical issues and the limitations encountered by the use of animal models turn the development of accurate in vitro models into an essential factor to study this disease. In this regard, the emergence of human induced pluripotent stem cell technology (hiPSCs) is an important tool, since it allows the recapitulation of patient\'s genetic diversity and allows the production of cell types of interest for studying the disease, such as neurons and glia. However, to date, there are no records of the production of in vitro models from hiPSCs of patients with MDD. In order to fill this gap, the present study aimed at the production and characterization of two types of in vitro models from hiPSCs of patients with MDD: serotonergic neurons, a monolayer cell culture, and cerebral organoids, a suspension cell culture. 5 patients\' hiPSCs lines were successfully differentiated into neurons and, in the immunocytochemistry assay, they expressed the 5-HT (serotonin), T5-HT (serotonin transporter), nestin (present in several neuronal cell types) and Tuj1 (cytoskeleton protein, neuron-specific), confirming the phenotype of serotonergic neurons. Differentiated cells also obtained positive results in calcium imaging tests and measurements of membrane potential changes, indicating that differentiated neurons were physiologically functional. Of 5 hiPSCs lines (one control and the other 4 of patients with MDD), only 1 survived to the differentiation process, originating cerebral organoids which presented expression of Sox2 (neural progenitor) and Tuj1 (mature neurons) markers and a correct structuring of the cytoarchitecture, with the progenitors located more internally in the ventricular zone, around the lumens filled with liquid and with the mature neurons located in the cortical plate, the outermost region of the cellular aggregates. Although the cerebral organoids production process needs improvement and better standardization, the production of these two types of in vitro models, made from hiPSCs of patients with MDD, is an important step for the future reduction of animal models use, elucidation of disease underlying mechanisms, identification of diagnostic biomarkers and drug screening in a personalized manner, in order to allow cheaper, more adequate and more efficient treatments for MDD

A Depressão é um transtorno mental grave e com alta prevalência, de difícil tratamento e fator de risco para inúmeras outras doenças e disfuncionalidades. Seus principais sintomas são o humor deprimido e a anedonia. Considera-se que a personalidade afeta a vulnerabilidade individual para a depressão além de influenciar os tipos de sintomas e complicações experimentadas pelo paciente. O presente trabalho aborda o tema do Transtorno Depressivo Maior em relação a características de temperamento e caráter, baseado no modelo psicobiológico de Cloninger. Questiona-se quais estariam associadas à Depressão Maior e ainda, quais outras se revelam protetoras da saúde e do bem estar físico, mental e social. Foi realizado um estudo transversal cujo objetivo foi comparar características de temperamento e caráter entre sujeitos com Transtorno Depressivo Maior moderado a grave e um grupo controle de sujeitos saudáveis, sem transtornos neuropsiquiátricos. Os pacientes deprimidos estavam sem uso de antidepressivos há pelo menos três semanas no momento da avaliação. Participaram 103 sujeitos (69 mulheres e 34 homens) em cada grupo, pareados por sexo e idade. Os mesmos preencheram o Inventário de Temperamento e Caráter (ITC), um teste autoaplicável e que avalia quatro dimensões de temperamento (Busca de Novidades, Evitação de Danos, Dependência de Recompensa e Persistência) e três de caráter (Autodirecionamento, Cooperatividade e Autotranscendência), cada qual com suas subdimensões. Foi realizada a comparação de dados sociodemográficos entre os grupos e a correlação entre as 7 dimensões de temperamento e caráter com escalas que avaliam afeto e humor no grupo de deprimidos e outras características do Transtorno Depressivo Maior, como tipo, idade de início da Depressão e número de episódios depressivos. Foi realizada a comparação das médias com o teste-t e das frequências com o chi-quadrado. Correlações foram realizadas para analisar as diferentes variáveis com o coeficiente de correlação de Pearson e nível de significância em 5% e com o teste de correção Bonferroni, estabelecendo nível de significância 0,007 para a comparação das 7 dimensões e 0,002 para as 25 subdimensões. Os resultados mostraram que pacientes com depressão apresentaram um escore maior de Evitação de Danos (M=25,58, DP=7,15) e um escore menor de Autodirecionamento (M=21,65, DP=8,03) comparados ao grupo controle (M=15,39, DP=6,09; M=33,43, DP=5,89, respectivamente, p<0,001). Por outro lado, sujeitos do grupo controle, além do Autodirecionamento, apresentaram também escores maiores em Cooperatividade (M=34,14, DP=4,85) comparados aos pacientes com depressão (M=29,44, DP=6,93, p<0,001). Por ser um estudo transversal não foi possível abordar a questão de traço ou estado-dependência destas dimensões de personalidade na Depressão Maior / Depression is a severe mental disorder of high prevalence, difficult treatment and risk factor for several other diseases and disorders. Its main symptoms are depressed mood and the anhedonia or loss of interest. There is evidence that personality affects the individual vulnerability for depression, as well as influences the types of symptoms and complications experimented by the patient. This work investigated the relationship between Major Depressive Disorder and temperament and character traits, based on Cloninger`s psychobiological model. We investigated which traits may be associated to Major Depression; furthermore, which others may reveal themselves protective of health and physical, mental and social welfare. A cross-sectional study was performed with the objective of comparing temperament and character traits between subjects with moderate to severe Major Depressive Disorder and a control group composed of healthy subjects without neuropsychiatric disorders. The depressed patients were antidepressant-free for at least three weeks at the time of the assessment. One hundred and three subjects (69 women and 34 men) participated in each group, matched by gender and age. These individuals filled out the Temperament and Character Inventory (TCI), a self-administered test which evaluates four dimensions of temperament (Novelty Seeking, Harm Avoidance, Reward Dependence and Persistence) and three of character (Self-Directedness, Cooperativeness and Self- Transcendence), each one with their own subscales. A comparison of sociodemographic data between the groups and the correlation between the seven dimensions of temperament and character was performed. Scales were used to assess affect and mood in the group of depressed individuals, as well as other characteristics of the Major Depressive Disorder, such as type, age of depression onset and the number of depressive episodes. The means were compared with t-tests and frequencies with the chi-square test. Correlations were made to analyze the different variables with Pearson correlation coefficient and the significance level at 5% threshold. The Bonferroni correction test was also applied, establishing the significance level in 0.007 for the comparison of the 7 dimensions and 0.002 for the 25 subscales. The results showed that patients with depression presented a higher Harm Avoidance score (M=25,58, SD=7,15) and a lower Self-Directedness score (M=21,65, SD=8,03) when compared to the control group (M=15,39, SD=6,09; M=33,43, SD=5,89, respectively, p<0,001). On the other hand, subjects from the control group, as well as increased Self- Directedness, also had significantly higher scores on Cooperativeness (M=34,14, SD=4,85) compared to patients with depression (M=29,44, SD=6,93, p<0,001). As this is a crosssectional study, it was not possible to approach the matter of trace or state-dependency of these dimensions of the Major Depression Personality

Major depressive disorder (MDD) is a heritable and highly debilitating condition with antidepressants, first-line treatment, demonstrating low to modest response rates. No current biological mechanism substantially explains MDD but both neurostructural and neurochemical pathways have been suggested. Further explication of these may aid in identifying subgroups of MDD that are better defined by their aetiology. Specifically, genetic stratification provides an array of tools to do this, including the intermediate phenotype approach which was applied in this thesis. This thesis explores genetic overlap with regional brain volume and MDD and the genetic and non-genetic components of antidepressant response. The first study utilised the most recent published data from ENIGMA (Enhancing Neuroimaging Genetics through Meta-analysis) Consortium's genome-wide association study (GWAS) of regional brain volume to examine shared genetic architecture between seven subcortical brain volumes and intracranial volume (ICV) and MDD. This was explored using linkage disequilibrium score regression (LDSC), polygenic risk scoring (PRS) techniques, Mendelian randomisation (MR) analysis and BUHMBOX (Breaking Up Heterogeneous Mixture Based On Cross-locus correlations). Results indicated that hippocampal volume was positively genetically correlated with MDD (rg= 0.46, P= 0.02), although this did not survive multiple comparison testing. Additionally, there was evidence for genetic subgrouping in Generation Scotland: Scottish Family Health Study (GS:SFHS) MDD cases (P=0.00281), however, this was not replicated in two other independent samples. This study does not support a shared architecture for regional brain volumes and MDD, however, provided some evidence that hippocampal volume and MDD may share genetic architecture in a subgroup of individuals, albeit the genetic correlation did not survive multiple testing correction and genetic subgroup heterogeneity was not replicated. To explore antidepressant treatment resistance, the second study utilised prescription data in (GS:SFHS) to define a measure of (a) treatment resistance (TR) and (b) stages of resistance (SR) by inferring antidepressant switching as non-response. GWAS were conducted separately for TR in GS:SFHS and the GENDEP (Genome-based Therapeutic Drugs for Depression) study and then meta-analysed (meta-analysis n=4,213, cases=358). For SR, a GWAS on GS:SFHS only was performed (n=3,452). Additionally, gene-set enrichment, polygenic risk scoring (PRS) and genetic correlation analysis were conducted. No significant locus, gene or gene-set was associated with TR or SR, however power analysis indicated that this analysis was underpowered. Pedigree-based correlations identified genetic overlap with psychological distress, schizotypy and mood disorder traits. Finally, the role of neuroticism, psychological resilience and coping styles in antidepressant resistance was investigated. Univariate, moderation and mediation models were applied using logistic regression and structural equation modelling techniques. In univariate models, neuroticism and emotion-orientated coping demonstrated significant negative association with antidepressant resistance, whereas resilience, task-orientated and avoidance-orientated coping demonstrated significant positive association. No moderation of the association between neuroticism and TR was detected and no mediating effect of coping styles was found. However, resilience was found to partially mediate the association between neuroticism and TR. Whilst the first study does not indicate a genetic overlap between regional brain volumes and MDD, it demonstrates the utility of the intermediate approach in complex disease. Antidepressant resistance was associated with neuroticism both genetically and phenotypically, indicating its role as an intermediate phenotype. Nonetheless, larger sample sizes are needed to adequately address the components of antidepressant resistance. Further work in antidepressant non-response may help to identify biological mechanisms responsible in MDD pathology and help stratify individuals into more tractable groups.