An epidemiologic study of the autoimmune diseases taken together has not been done heretofore. The National Patient Register of Denmark is used to estimate population prevalence of 31 possible or probable autoimmune diseases. Record linkage is used to estimate 465 pairwise comorbidities in individuals among the 31 diseases, and familial aggregation among sibs, parents and offspring. The prevalence of any of the 31 diseases in the population is more than 5%. Within individuals, there is extensive comorbidity across the 31 diseases. Within families, aggregation is strongest for individual diseases, and weak across diseases. These data confirm the importance of the autoimmune diseases as a group, and suggest that common etiopathologies exist among them.

Although there is growing evidence of links between the cortisol stress response and personality, the nature of the relationships and the underlying mechanisms require further clarification. The purpose of this study was to examine associations between personality traits and cortisol responses to stress using the Revised NEO Personality Inventory five-factor model of personality. In total, 68 healthy adults, aged 18-30 years, completed the personality assessment and underwent a laboratory psychological stress test that consisted of a 5 min speech and 5-min of mental arithmetic. Findings showed that in the sample as a whole, less Openness was associated with lower cortisol responses to the challenge. Cortisol responses also corresponded to certain personality dimensions in a gender-specific manner. Blunted cortisol responses were associated with higher Neuroticism in women and with lower Extraversion in men. These findings suggest that personality traits that have been traditionally associated with greater psychopathology were also associated with blunted HPA axis responses to stress.

The purpose of this study was to determine the prevalence, sociodemographic correlates, and comorbidity of recurrent headache in children in the United States. Participants were individuals aged 4 to 18 years (n = 10 198) who participated in the National Health and Nutrition Examination Surveys. Data on recurrent and other health conditions were analyzed. Frequent or severe headaches including migraine in the past 12 months were reported in 17.1% of children. Asthma, hay fever, and frequent ear infections were more common in children with headache, with at least 1 of these occurring in 41.6% of children with headache versus 25.0% of children free of headache. Other medical problems associated with childhood headaches include anemia, overweight, abdominal illnesses, and early menarche. Recurrent headache in childhood is common and has significant medical comorbidity. Further research is needed to understand biologic mechanisms and identify more homogeneous subgroups in clinical and genetic studies. Keywordsheadache; migraine; comorbidity; prevalence Headache is a common complaint in children and adolescents. The most frequent type of recurrent headache in young children is migraine, 1 while the frequency of tension type headache increases in the later years of childhood. Recurrent headaches can negatively impact a child's life in several ways, including school absences, decreased academic performance, social stigma, and impaired ability to establish and maintain peer relationships. The quality of life in children with migraine is impaired to a degree similar to that in children with arthritis or cancer. 2 There has been limited population-based research on headache and migraine in children, particularly in the United States. Most of our knowledge regarding the prevalence and demographic correlates of migraine is derived from school-based questionnaire studies in European countries [3][4][5][6] and some from the United States. 7,8 Prevalence estimates for headache in prepubertal children range from 2.4% to 17% for migraine and 4% to 5% for frequent or severe headache. For the postpubertal ages estimates are considerably higher, ranging from NIH-PA Author ManuscriptNIH-PA Author Manuscript NIH-PA Author Manuscript 5% to 18% for migraine and 9% to 29% for other frequent or severe headaches. Despite the impact of headache on pediatric health, only 1 population-based American study to date has examined the frequency of recurrent headache in children. 9 Individuals who suffer from migraine or severe headaches are also diagnosed with certain other medical conditions at a higher than expected frequency. Comorbidity can significantly influence the delivery of medical care as it may confound diagnosis and provide special therapeutic challenges. No population-based study to date has systematically examined the patterns of medical comorbidity of recurrent headache or migraine in childhood. Knowledge of other biologic systems involved would not only help physicians provide better care for their patients but may also ...

Migraineurs, specifically those with aura, exhibited less decline on cognitive tests over time vs nonmigraineurs. For the Mini-Mental State Examination, these effects were only apparent among those who were older than 50 years.

BACKGROUND-Although much is known about risk factors for the initiation of alcohol use, abuse and dependence, few population-based studies have examined the predictors of transitions across these stages.