The Prevalence and Comorbidity Rates of ADHD Among School-Age Children in Turkey.

Objective: The aim of the present study was to explore the prevalence and comorbidity rates of ADHD in a community sample of school-age children. Method: Participants were 1,508 children aged 6 to 14 years. Parents and teachers of each child completed the Turgay Diagnostic and Statistical Manual of Mental Disorders (4th ed.; DSM-IV) Disruptive Behavior Disorders Rating Scale (T-DSM-IV-S). Screen-positive cases were interviewed using the Schedule for Affective Disorders and Schizophrenia for School-Age Children-Present and Lifetime Version (K-SADS-PL). Diagnoses were based on DSM-IV criteria. Results: The prevalence rate of ADHD was 8%. Children from extended families had extremely high rates (46.4%) of ADHD. Sixty percent of children with ADHD had one or more comorbid diagnoses. The most common comorbidities were learning disorders (35.7%) and oppositional defiant disorder (22.6%). Conclusion: The prevalence and comorbidity rates of ADHD in school-age children in Turkey are similar to those found in previous studies in other countries.

Increased urinary 6-hydroxymelatoninsulfate levels in attention deficit hyperactivity disorder diagnosed children and adolescent.

There are some studies in attention deficit hyperactivity disorder (ADHD) which note altered circadian rhythms, suggesting abnormalities in melatonin physiology. In order to better characterize the possible melatonin alteration in ADHD, in this study we aimed to detect daytime, nighttime and 24 h levels of 6-hydroxymelatoninsulfate (6-OH MS) in the patients diagnosed with ADHD. Twenty-seven patients between 6 and 16 years-old, who had been diagnosed initially with ADHD, but without other physical and psychiatric disease history and who had not taken psychotropic pharmacotherapy for six months, plus 28 healthy volunteer controls, were included in the study. Urine samples were collected during the whole 24 h cycle, daytime and nighttime separately to assess the time-dependent excretion of the 6-OH MS, which is the main urine metabolite of melatonin. The Enzyme-Linked Immunosorbent Assay (ELISA) method was used for measuring the urine 6-OH MS level. Daytime (15.4 (8.9-24.8) ng/ml vs 6.9 (2.5-15.9) ng/ml, p=0.002), nighttime (102.9 (65.3-197.7) ng/ml vs 61.5 (37.2-114.4) ng/ml, p=0.012) and 24 h (54.1 (34.6-83.9) ng/ml vs 27.3 (14.3-48.9) ng/ml, p=0.000) 6-OH MS levels median (25p-75p) were found to be significantly higher in the ADHD group. After adjustment for age and sex, there was a statistically significant difference between the ADHD group (59.8 ± 4.9) and control group (33.8 ± 4.8) in 24-h 6-OH MS levels (F(1, 51)=13.673, p=.001, partial η2=.211). There was no relationship between 6-OH MS levels and Conners Parent Rating Scale short form subscale scores for the ADHD group. These findings indicate that melatonin production is increased in ADHD cases. Further research is needed to determine and thereby understand the mechanisms underlying the higher melatonin production, to assess the impact of altered melatonin on the pathophysiology of ADHD.