Impact of birth season on the years of life lost from respiratory diseases in the elderly related to ambient PM

BACKGROUND@#Ambient fine particle (PM@*METHODS@#A time-stratified case-crossover design was used to analyze YLL from respiratory diseases in the elderly related to ambient PM@*RESULTS@#Each 10 μg/m@*CONCLUSIONS@#Birth season which reflects the early-life PM

Associations between season of birth and age both at menarche and at menopause / 中华流行病学杂志

Objective To examine the associations between season of birth and factors as age at menarche,age at menopause and reproductive span.Methods A total of 285 186 female from the China Kadoorie Biobank,with complete data on critical variables and had menarche at 9-18 years old,were included.A total of 132 373 female with natural menopause were included for the analysis on age at menopause and reproductive span.Multiple linear regression models were used to assess the associations of birth season and the age at menarche,menopause,and reproductive span.Subgroup analyses were performed on birth cohorts and urban/rural residence.Results Compared with the Spring-born (March,April,and May),participants who were born in Summer (June,July,and August),Autumn (September,October,and November),and Winter (December,January,and February)appeared late on both age at menarche and menopause.Multivariable-adjusted coefficients (95％ CI)appeared as 0.14 (95％CI:0.13-0.16),0.26(95％CI:0.24-0.27),0.10 (95％CI:0.08-0.12) for age at menarche respectively and 0.14 (95％CI:0.08-0.20),0.18 (95％CI:0.12-0.24),0.09 (95％CI:0.03-0.16) for age at menopause respectively.No statistically significant association was found between the season of birth and reproductive span.The association was consistent between urban and rural residents and across the birth cohorts.Conclusions female born in spring showed both earlier age on both menarche and menopause,compared to the ones born in other seasons.Our findings suggested that exposures in early life with some degree of seasonal variation might influence the development of female reproductive system.

Associations between season of birth and age both at menarche and at menopause / 中华流行病学杂志

Objective To examine the associations between season of birth and factors as age at menarche,age at menopause and reproductive span.Methods A total of 285 186 female from the China Kadoorie Biobank,with complete data on critical variables and had menarche at 9-18 years old,were included.A total of 132 373 female with natural menopause were included for the analysis on age at menopause and reproductive span.Multiple linear regression models were used to assess the associations of birth season and the age at menarche,menopause,and reproductive span.Subgroup analyses were performed on birth cohorts and urban/rural residence.Results Compared with the Spring-born (March,April,and May),participants who were born in Summer (June,July,and August),Autumn (September,October,and November),and Winter (December,January,and February)appeared late on both age at menarche and menopause.Multivariable-adjusted coefficients (95％ CI)appeared as 0.14 (95％CI:0.13-0.16),0.26(95％CI:0.24-0.27),0.10 (95％CI:0.08-0.12) for age at menarche respectively and 0.14 (95％CI:0.08-0.20),0.18 (95％CI:0.12-0.24),0.09 (95％CI:0.03-0.16) for age at menopause respectively.No statistically significant association was found between the season of birth and reproductive span.The association was consistent between urban and rural residents and across the birth cohorts.Conclusions female born in spring showed both earlier age on both menarche and menopause,compared to the ones born in other seasons.Our findings suggested that exposures in early life with some degree of seasonal variation might influence the development of female reproductive system.

Caracterização e distribuição de cronotipos no sul do Brasil: diferenças de gênero e estação de nascimento / Characterization and distribution of chronotypes in southern Brazil: gender and season of birth differences

OBJETIVO: Investigar a tipologia circadiana e as diferenças de gênero em universitários do sul do Brasil. MÉTODOS: Voluntários (736) de 17 a 49 anos preencheram a versão brasileira do Questionário de Cronotipo (QC), tradução do Morningness-eveningness Questionnaire (MEQ) de Horne e Õstberg. Medidas de tendência central e dispersão e curva de distribuição dos escores do QC (Kolmogorov-Smirnov) foram calculadas de acordo com gênero (teste t de Student), idade, estação de nascimento e desconforto com o horário de verão (qui-quadrado). RESULTADOS: Foram incluídos 648 indivíduos (36 por cento homens, 64 por cento mulheres), com perdas de 12 por cento por questionários incorretos. A distribuição dos escores do QC evidenciou uma curva normal (amplitude = 18-77; média = 46,6; desvio-padrão = 10,8). Nesta amostra, 32 por cento foram vespertinos, 54 por cento intermediários e 14 por cento matutinos. As médias do QC foram significativamente diferentes (p = 0,003): homens (44,9 ± 10,8) comparados com mulheres (47,5 ± 10,7) e 70 por cento dos que nasceram na primavera e no verão foram vespertinos (p = 0,015), sem associação gênero-estação do ano. CONCLUSÃO: Homens e nascidos na primavera-verão evidenciaram preferência pela vespertinidade, não havendo diferença de gênero com relação à estação de nascimento. Nossos resultados estão de acordo com estudos realizados no hemisfério norte que mostraram, também, uma associação entre a estação de nascimento e o cronotipo.

OBJECTIVE: To analyze circadian typology (diurnal preference) and gender differences in a university student population from Southern Brazil. METHODS: Seven hundred and thirty six university student volunteers, with an age range 17-49 years, filled the Brazilian version of the Chronotype Questionnaire (CQ), the portuguese translation of the Horne and Õstberg's Morningness-Eveningness Questionnaire (MEQ). Central and dispersion tendencies measures and CQ scores distribution curve (Kolmogorov-Smirnov) were calculated according to gender (Student t), age, birth season, and daylight-saving time discomfort (qui-square). RESULTS: Six hundred and fourty eight individuals (36 percent men; 64 percent women) were included in this study, with 12 percent of losses due to incorrect questionnaires. CQ score distribution was correlated to the normal curve (range=18-77; mean=46.6; s.d.=10.8). In this sample, 32 percent were evening-types; 54 percent were intermediate-types, and 14 percent were morning-types. CQ means were significatively different (p=0.003) when males (44.9±10.8) were compared to females (47.5±10.7), and 70 percent of those born during spring and summer were evening-types (p=0.015).There was no gender-by-season association. CONCLUSIONS: Men, and Individuals born in spring and summer, presented eveningness preference, without gender-birth season interaction. Our results are also in agreement with studies performed in the Northern Hemisphere, which showed an association between birth season and diurnal preference.

The Relation of Mood Disorder to Season of Birth / 신경정신의학

To examine the relation of mood disorder to season of birth, we analyzed the data of 156 male and female mood disorder patients who were admitted to or visited NaJu National Mental Hospital from March 1997 to June 1997. The results of this study were as follows: 1) There was a significant difference of birth season distribution in patients with mood disorder compared with that of geneal population. We suggest that birth seasonal factors have influence on onset of mood disorder. 2) High onset rate in spring was noted in patients with mood disorders. Winter-born patients had a significantly low onset rate in autumn, and autumn-born patients had a significantly low onset rate in winter. The results suggest that seasonal factors affecting onset of schizophrenia are associated with onset of mood disorder. Further studies should follow to find out concrete and objective relation of mood disorder to season of birth.