Thesis (M.A.)--York University, 2007. Graduate Programme in Kinesiology and Health Science. / Typescript. Includes bibliographical references (leaves 54-62). Also available on the Internet. MODE OF ACCESS via web browser by entering the following URL: http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&res_dat=xri:pqdiss&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&rft_dat=xri:pqdiss:MR29310

Background: Several neuropsychiatrie disorders have shown season of birth associations. Low cerebrospinal fluid (CSF) levels of the serotonin metabolite 5-HIAA and the dopamine metabolite HVA have been associated with suicidal behaviour, impulsivity, and aggression. This thesis investigated associations between the season of birth, the CSF levels of three monoamine metabolites (including MHPG of norepinephrine), the scales of the diagnostic interview for borderline patients (DIB), and psychiatric diagnoses. Also, the methods of suicide were investigated in relation to the season of birth. Methods: We studied a clinical sample of 241 patients in Stockholm with mood, anxiety and adjustment disorders with respect to the CSF levels of monoamine metabolites in relation to the season of birth, and in relation to the DIB in an overlapping sample. We also analysed all completed suicides during the 42 years 1952- 1993inVästerbottenin northern Sweden (1466 cases) by multiple logistic regressions to relate suicide methods with season of birth, gender, age, urban-rural residence, marital status, year of suicide, and season of suicide. For the 20 years 1961- 1980 (693cases), psychiatric in-patient and out-patient records were also examined for any history of psychiatric contacts and psychiatric diagnoses. In two mutually independent samples, we investigated the DIB in relation to the season of birth. Results: In the Stockholm sample, those born during February to April had significantly lower CSF levels of 5-HIAA, and those born during October to January had significantly higher CSF levels of HVA, HVA/5-HIAA, and HVA/MHPG, as well as (non-significantly) higher levels of 5-HIAA. Those with an intermediate score of section II (impulse action patterns) of the DIB had significantly higher CSF levels of 5-HIAA and HVA, and they were significantly more likely to have been born during October to January. In the Västerbotten register, those born during February to April were significantly more likely to have preferred hanging rather than poisoning or petrol gases, and conversely for those born during October to January. These associations with suicide methods were found for the total sample and for those without any history of psychiatric contacts, but not for those with psychiatric contacts. Conclusions: Suicidal behaviour shows statistically significant variation according to the season of birth, most probably mediated by a variation in an independent trait of vulnerability to suicide based on neurodevelopmental parameters, particularly the serotonergic system. The suicidal process differs between those who seek psychiatric care compared to those who do not, reflecting differences in the diagnostic spectra and in the extent of mental illness. / <p>Härtill 6 delarbeten.</p>

The phenomenon of seasonality of birth in schizophrenia is important in the study of the etiology of this mental disorder because it helps to give directions for further research. Patients' hospital files from 1981 to 1991 of two of the largest hospitals with psychiatric wards in Taiwan were reviewed, and dates of birth collected on 3346 patients diagnosed with schizophrenia. After adjusting for the variations of the total monthly births in the population, an Auto-Regressive Integrated Moving Average (ARIMA) model was applied. Results support a seasonality phenomenon and indicate a disproportional excess of births in schizophrenia in the cold months (Nov. to Feb.) compared to the hot months (May to Aug.). These findings are compatible with many other studies in other countries and climates. Further investigations of season-related environmental factors in the etiology of schizophrenia are recommended.

Background: Schizophrenia is a chronic, debilitating mental disorder characterized by positive (e.g., hallucinations, delusions) and negative (e.g., catatonia, flat affect) signs and symptoms. Many studies suggest that individuals born in winter or spring months are at increased risk for schizophrenia. Study Objectives: 1) To determine whether season of birth affects risk for schizophrenia in the Irish Study of High Density Schizophrenia Families (ISHDSF). 2) To examine, by computer simulation, power to detect genetic associations with schizophrenia under a variety of conditions and using different analytic strategies. 3) To test whether specific genes are associated with schizophrenia in the Irish Case Control Schizophrenia Study (ICCSS), using different analytic strategies to account for season of birth. Methods: A case-control design was used to examine the relationship between schizophrenia and season of birth. Cases were individuals from the ISHDSF diagnosed with schizophrenia. Controls were the general population of Ireland, with data provided by Ireland’s Central Statistics Office (CSO). The birth frequencies for each month or quarter were compared in the two groups by a chi square test. Computer simulations were conducted to examine power to detect schizophrenia susceptibility loci using either all cases or only cases born in high-risk months, under different conditions and models for how genetic risk and season of birth interact to influence risk for schizophrenia. Data for six genetic markers from the ICCSS were analyzed for evidence of association, using all cases, and then using only cases born in high-risk months. Setting and Study Participants: ISHDSF families were ascertained through inpatient psychiatric care facilities serving >95% of the Irish population. Diagnoses were established using DSM-III-R criteria, and birthdates were recorded for all individuals. The Irish CSO provided aggregate, population-level data for number of births in Ireland by month for the years 1976-2000 and by quarter for the years 1900-2000. The ICCSS is a sample of schizophrenic and control individuals who have been genotyped at many loci across the genome. Schizophrenics were ascertained through in- and outpatient psychiatric facilities, had diagnoses verified by an expert, and their birthdates recorded. Controls were selected from several sources, e.g. blood donation centers, and denied any lifetime history of schizophrenia. For each subject in the ICCSS, all four grandparents were born in Ireland or the United Kingdom. Results: Number of births in each month was compared for schizophrenics in the ISHDSF and general population controls, resulting in a chi square of 19.44 (p value ~ 0.054, 11 df). Simulations revealed that, in some circumstances, power to detect genetic associations was increased by restricting cases to those born in high-risk months. Analysis of data from the ICCSS revealed that restricting cases to high-risk birth months increased the evidence for association for three of six markers tested, two of which were associated with the gene FBXL21. Conclusions: Birth in the months of March, April, or May appears to be associated with elevated risk for schizophrenia in the ISHDSF. In attempting to find susceptibility loci for schizophrenia, restricting genetic association analyses to schizophrenics born in high-risk months may result in increased power to detect genetic association in some circumstances.

The primary objective of this research was to study the effects of agro-ecological regions (as represented by the veld types in four different areas), sex, season of birth, the interaction between sex and season of birth as well as the interaction between veld type and season of birth on selected anthropometrical measurements (body dimension measurements). The correlations between these selected anthropometrical measurements were also investigated in this study. Data from four herds of Nguni cattle comprising of 416 animals (Loskop South, Fort Hare, Kroonstad and Warmbaths with 115, 106, 97, and 98 animals respectively) was analysed. Measurements were taken in different seasons at each area or location. Statistical analyses of the data were done using the general linear model (GLM) procedure of the Statistical Analysis System (SAS, 2002). The results of this study indicate that veld type, sex and the interaction between sex and veld type did not significantly (P < 0.05) affect the growth (selected anthropometrical measurements) of Nguni cattle. In all the four agro-ecological regions (veld type in the different regions), season of birth, the interaction between sex and season of birth (Sex*BS) and the interaction between season of birth and veld type (V*BS) showed a significant effect (P< 0.05) on selected body dimensions. Animals that were born during the winter and spring seasons were heavier (P<0.05, 333.37 kg and 336.95 kg respectively) than those born in summer (270.35 kg) and autumn (286.29 kg). The same can be said of other body dimensions (M, L, HW, HG, SH and HH), whereby the animals that were born during winter and spring seasons had higher values (P<0.05) than their counterparts born in summer and autumn. This tendency was also observed for SC although the difference was not statistically significant. In conclusion, the study suggested that season of birth, the interaction between sex and season of birth (Sex*BS) and the interaction between veldtype (agro-ecological region) and season of birth (V*BS) are important sources of variation in growth of beef cattle, with special reference to Nguni cattle. It is therefore recommended that season of birth and its interaction with both veld type and sex should be given considerable attention in any extensive beef production system (with special reference to the Nguni breed) employed in South Africa. Knowledge of the influence of agro-ecological factors on the growth of beef cattle is of great importance for measuring production capacity, designing and implementing strategies to alter the extensive beef production system and thus to increase the output to ensure a more sustainable economic advantage. / Dissertation (Magister Institutionis Agrariae (Animal Production))--University of Pretoria, 2007. / Animal and Wildlife Sciences / unrestricted

The relative age effect (RAE) is associated with (dis)advantages in competitive sports. While the RAE in elite male soccer reveals a skewed birthdate distribution in relation to a certain cut-off date, research of RAE in elite female soccer is affected by small number of samples and conflicting results. The purpose of this study was to investigate the RAE in elite adult German soccer regarding gender and competition level. The sample comprised 680 female and 1,083 male players of the two top German leagues during the 2019/20 season and German national teams (A-Team to Under 19). Differences between the observed and expected birthdate distributions were analyzed using chisquare statistics and effect sizes followed by calculating odds ratios. Results showed a statistically significant RAE with small effect size across all players included for both genders (female players: P < 0.001, W = 0.16, male players: P < 0.001, W = 0.23). The identified RAE was based on an over-representation of players born at the beginning of the year. According to gender and competition level, RAEs were more pronounced in German male soccer. While significant RAEs were found among males in the first two leagues (first league: P < 0.001, W = 0.19, second league: P < 0.001, W = 0.26), the RAE of females was more pronounced in the second league (first league: P = 0.080, W = 0.16, second league: P = 0.002, W = 0.20). The analysis of RAE regarding the national teams revealed a statistically significant RAE with large effect size for only the youngest investigated age group of male players (Under 19: P = 0.022, W = 0.52). Our data show an RAE in female and male German adult soccer, which could be accompanied by a loss of valuable elite players during the youth phase of the career. Consequently, the pool of talented players at the adult level would be limited.

Abstract Both genetic and biological and psychosocial environmental risk factors contribute to the aetiology of schizophrenia spectrum disorders. Among the much studied environmental risk indicators are parental Communication Deviance (CD) and the winter or spring birth of a child. Genetic and environmental risk factors do not function in isolation from each other, but gene-environment interactions play a major role in the aetiology of psychotic disorders. The aim of this doctoral thesis is to investigate the role of parental CD as a risk factor (together with other risk indicators) for thought disorders and schizophrenia spectrum disorders in an adoptive child. A systematised review was performed concerning the association between parental Communication Deviance and schizophrenia spectrum and thought disorders in offspring. A meta-analysis could only be performed for the association of parental CD with schizophrenia spectrum disorders in offspring. A large overall effect size was found (0.79, 95%CI 0.21–1.37). The studies included in the systematised review suggest that frequent parental CD and thought disorders in the offspring are connected with each other. The two original studies are based on the data derived from the total sample of the Finnish Adoptive Family Study (n=382). First, the association between parental Communication Deviance scored from individual and family Rorschach protocols and the characteristics of the adoptive child and the parents themselves was investigated. The variability of CD in the adoptive parents in individual and family Rorschach situations was most closely associated with the characteristics of the parents themselves. The association of an adoptive child’s thought and schizophrenia spectrum disorders with the child’s genetic risk for schizophrenia spectrum disorders, winter or spring birth, and parental Communication Deviance, and their interactions was also explored. The adoptive child’s thought disorders were associated only with parental CD. None of the risk indicators or their interactions predicted the adoptee’s schizophrenia spectrum diagnosis. In conclusion, the results indicate that the amount of Communication Deviance is a stable trait of an individual. It may be considered as a risk indicator for schizophrenia spectrum disorders in offspring and, with a lower level of confidence, also for thought disorders in offspring. / Tiivistelmä Skitsofreniaspektrin sairauksien varsinaisia syytekijöitä ei tunneta, mutta niillä on lukuisia sekä perimään että biologiseen ja psykososiaaliseen ympäristöön liittyviä riskitekijöitä. Nykytietämyksen mukaan riskitekijät eivät vaikuta sairauden syntyyn itsenäisesti, vaan perimän ja ympäristön vuorovaikutuksella on merkittävä osuus. Paljon tutkittuja ympäristöön liittyviä riskitekijöitä ovat lapsen talvi- tai kevätsyntymä ja vanhempien hajanainen kommunikaatio. Tässä väitöskirjassa tutkitaan vanhempien hajanaista kommunikaatiota adoptiolapsen ajatushäiriöiden ja skitsofreniaspektrin sairauksien riskitekijänä. Vanhempien hajanaisen kommunikaation ja lapsen skitsofreniaspektrin sairauksien ja ajatushäiriöiden yhteydestä laadittiin systemaattinen katsaus. Meta-analyysi voitiin tehdä vain skitsofreniaspektrin sairauksiin liittyen. Vanhempien hajanaisen kommunikaation ja lapsen skitsofreniaspektrin sairauksien välisellä yhteydellä havaittiin olevan suuri efektikoko (0,79, 95 % luottamusväli 0,21–1,37). Katsaukseen sisällytetyt tutkimukset viittaavat siihen, että vanhempien hajanaisella kommunikaatiolla ja lapsen ajatushäiriöillä on myös yhteys. Väitöskirjan alkuperäistutkimukset perustuvat Suomalaisen adoptiolapsiperhetutkimuksen aineistoon (n= 382). Aluksi tutkittiin vanhempien yksilö- ja perhe-Rorschach-tilanteissa mitatun hajanaisen kommunikaation määrän ja lapsen ja vanhempien ominaisuuksien välistä yhteyttä. Hajanaisen kommunikaation määrän vaihtelu selittyi pääosin vanhempien ominaisuuksilla. Seuraavaksi tutkittiin adoptiolapsen ajatushäiriöiden ja skitsofreniaspektrin sairauksien yhteyttä lapsen skitsofreniaspektrin sairauksille altistavan perimän, talvi- tai kevätsyntymän ja vanhempien hajanaisen kommunikaation kanssa. Huomioon otettiin myös riskitekijöiden yhteisvaikutukset. Mikään riskitekijä tai niiden yhteisvaikutus ei ollut yhteydessä lapsen skitsofreniaspektrin sairauteen. Lapsen ajatushäiriöt olivat yhteydessä ainoastaan vanhempien hajanaiseen kommunikaatioon. Tutkimuksen tulokset osoittavat, että vanhempien hajanainen kommunikaatio on kohtalaisen muuttumaton piirre, joka on lapsen skitsofreniaspektrin sairauksien riskitekijä. Tulokset viittaavat myös siihen, että vanhempien hajanainen kommunikaatio voi olla lapsen ajatushäiriöiden riskitekijä.