During the past year we have completed extensive analyses of the data from both the child and adult components of the NHANES surveys and have published several papers. First, we reported the first prevalence rates and demographic correlates of DSM-IV disorders in a nationally representative sample of children ages 8-15 using NHANES 2001-2004 (Merikangas et al, 2010). Second, we investigated the association of childhood headache with biomarkers for cardiovascular and cerebral-vascular disease among 11,770 children aged 4 to 19 years old in NHANES 1999 -2004 data. We found mean values for homocysteine, C reactive protein, and body mass index were higher in children with than without headaches, and more children with headaches were in the highest quintile for these factors. Serum and red cell folate were lower in children with headache. More children with headache (32% in children <12 years) than without headache (18%) were in the highest quintile of risk for 3 or more of these factors. The findings indicate that these important risk factors for long-term vascular morbidity cluster with severe or recurrent headache in childhood or adolescence. Recognition of the subgroup among children with headache in whom these risk factors concentrate may permit improved preventive management (Nelson, 2010). We also examined ethnic differences in 12-month prevalence estimates patterns of service utilization of DSM-IV major depressive disorder, ADHD, and conduct disorder. Our results indicate that there were no differences in the prevalence of major depressive disorder or anxiety disorders or conduct disorder between ethnic subgroups. However, Mexican-American youth had lower one-year prevalence rates, and lower rates of mental health service use among those with ADHD compared to non-Hispanic Whites. Inclusion of parental country of birth in analyses accounted for the observed ethnic differences in the prevalence of ADHD and differences in service utilization. Non-Hispanic Blacks had more symptoms of panic disorder, while Mexican-Americans had more symptoms of eating disorders. The manuscript describing these findings has been submitted for publication. We have also analyzed prevalence of physician diagnosed sleep disorders and their demographic and biological correlates. We found that females had greater rates of incomnia, whereas males had higher rates of sleep apnea. There were also pronounced ethnic differences in the prevalence of insomnia, restless leg syndrome (RLS) and sleep apnea, with higher rates of RLS and sleep apnea in whites compared to either Hispanics of non-hispanic blacks, and greater rates of insomnia among Hispanics and non-hispanic blacks. The rates of insomnia and RLS were fairly statble across adulthood, while a steep increase in rates of sleep apnea with increasing age. A better understanding of the prevalence of sleep disorders will help us understand the public health impact of these disorders, and our analyses of the comorbidity and biomarkers are a significant step towards understanding the biologic mechanisms of sleep, sleep disorders, and associated conditions. We also have investigated whether and to what degree smoking affect the onset and clinical correlates of DSM-IV diagnosed depression and anxiety in adolescents, and how this comorbidity affects smoking behavior among 4240 adolescents, 12-19 years of age, from NHANES. We found that ever smokers had more than two times the odds of DSM-IV anxiety and depression as compared to never smokers. Furthermore, smokers were more likely to suffer impairment across multiple domains, and seek mental health services for depression. These effects were increased in daily and dependent smokers as compared to non-daily and non-dependent smokers, respectively. Smokers with co-morbid with depression/anxiety were also more likely to have increased levels of cigarette consumption. The onset of smoking tended to occur prior to the onset of the first symptom of anxiety and depression in 60.3% and 63.1% of the youth, respectively. Regarding temporal ordering, there was no clear causal pathway. We have recently begun to examine the correlates of mental disorder at symptom level and the association with the patterns and determinants of service utilization.Future analyses will then examine the risk factors and biological correlates of these conditions in the general population. We will prioritize our analyses to address the key study questions that are the focus of our own research. Public Health Impact: These findings that provide the first estimates of mental disorders in a nationally representative sample of youth highlight the high magnitude of mental disorders that lead to impairment in U.S. youth, and the striking lack of mental health service use in children with severe disorders particularly anxiety disorders. This research also broadens our knowledge and provides new information on cardiovascular disorders and biomarkers in U.S. adults and youth. These results are a significant first step towards research to understand biologic mechanisms, identify more homogeneous subgroups in clinical and genetic studies, and develop better clinical management.
