RESUMO
OBJECTIVE: To confirm prior findings that the larger the maximum monthly increase in solar insolation in springtime, the younger the age of onset of bipolar disorder. METHOD: Data were collected from 5536 patients at 50 sites in 32 countries on six continents. Onset occurred at 456 locations in 57 countries. Variables included solar insolation, birth-cohort, family history, polarity of first episode and country physician density. RESULTS: There was a significant, inverse association between the maximum monthly increase in solar insolation at the onset location, and the age of onset. This effect was reduced in those without a family history of mood disorders and with a first episode of mania rather than depression. The maximum monthly increase occurred in springtime. The youngest birth-cohort had the youngest age of onset. All prior relationships were confirmed using both the entire sample, and only the youngest birth-cohort (all estimated coefficients P < 0.001). CONCLUSION: A large increase in springtime solar insolation may impact the onset of bipolar disorder, especially with a family history of mood disorders. Recent societal changes that affect light exposure (LED lighting, mobile devices backlit with LEDs) may influence adaptability to a springtime circadian challenge.
Assuntos
Transtorno Bipolar/epidemiologia , Radiação Eletromagnética , Internacionalidade , Estações do Ano , Adolescente , Adulto , África/epidemiologia , Idade de Início , Ásia/epidemiologia , Austrália/epidemiologia , Europa (Continente)/epidemiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , América do Norte/epidemiologia , Sistema Solar , América do Sul/epidemiologia , Luz Solar , Adulto JovemRESUMO
OBJECTIVE: New Mexico (NM) has the highest rate of non-firearm-related homicide in the USA and ranks 20th in firearm-related homicides. Because non-firearm-related homicides are inadequately described in the literature, characterisation of non-firearm-related homicide victims will enhance efforts to reduce homicides. METHODS: Homicide victims were identified through the Office of the Medical Investigator. Age-specific and age-adjusted homicide death rates were calculated for 2001-3 by sex and race/ethnicity, and associations between covariates and non-firearm-related homicide were measured. RESULTS: Non-firearm-related homicides comprised 33% of US homicide victims, 47% of NM homicide victims, and 74% of NM American Indian (AI) homicide victims. Of 212 NM non-firearm-related homicide victims, 37% had been beaten, 32% had been stabbed, and 12% had been strangled. Females comprised 30% of non-firearm-related homicide victims and 18% of firearm-related homicide victims. A blood alcohol concentration (BAC) >or=0.08 mg/dl was detected among 43% of non-firearm-related (61% of AI) and 33% of firearm-related (50% of AI) homicide victims. Non-firearm-related homicide rates were highest among AI men aged 25-34 years (31/100,000). Non-firearm-related homicide victims were more likely than firearm-related victims to be AI (adjusted odds ratio (AOR) 4.20; 95% CI 2.16 to 8.16) and female (AOR 2.05; 95% CI 1.27 to 3.31), and to have had a BAC >or=0.08 mg/dl (AOR 1.65; 95% CI 1.08 to 2.52). CONCLUSIONS: Homicide-prevention efforts among AIs in NM should focus on non-firearm-related homicides. The association between excessive drinking and non-firearm-related homicide should be further characterised. Continued surveillance for non-firearm-related homicides will assist these efforts.