The aim of the study was to determine the association between vitamin D and attention deficit hyperactivity disorder (ADHD), and difference in the level of vitamin D in ADHD children and control. This a case-control study carried out in school health and primary health care clinics. A total of 1,331 children and adolescents who were diagnosed with ADHD based on clinical criteria and standardized questionnaires were enrolled in this study and were matched with 1,331 controls, aged 5-18 years old. Data on body mass index (BMI), clinical biochemistry variables including serum 25-hydroxyvitamin D were collected. The study found significant association between ADHD and vitamin D deficiency after adjusting for BMI and sex (adj. OR 1.54; 95 % CI 1.32-1.81; P < 0.001). Majority of the ADHD children were in the age group 5-10 years (40.7 %), followed by 11-13 years (38.4 %). The proportion of BMI <85th percentile was significantly over represented in ADHD group as compared to healthy control (87.8 vs. 83 %; P < 0.001, respectively), while on the other hand, BMI >95th percentile was over represented in the control than ADHD group (7.6 vs. 4.6 %; P < 0.001, respectively). Mean values of vitamin D (ng/mL) were significantly lower in ADHD children (16.6 ± 7.8) than in healthy children (23.5 ± 9.0) (P < 0.001). There was significant correlation between vitamin D deficiency and age (r = -0.191, P = 0.001); calcium (r = 0.272, P = 0.001); phosphorous (r = 0.284, P = 0.001); magnesium (r = 0.292, P = 0.001); and BMI (r = 0.498, P = 0.001) in ADHD children. The vitamin D deficiency was higher in ADHD children compared to healthy children.

Background:It has been reported that ferritin and iron deficiency may be related to the path physiology of attention deficit hyperactivity disorder (ADHD).Aim:The aim of this study was to determine the association between iron deficiency and ADHD and the impact and role of iron deficiency on the development of ADHD in children.Subjects and Methods:The study based on the case-control study age- and sex-matched control and conducted at the School Health and Primary Healthcare Clinics, Qatar. A total of 630 children with ADHD aged 5-18 and 630 controls aged 5-18 years old. Sociodemographic and clinical data were collected, including physician diagnosis. The health status of the subjects was assessed by ascertaining clinical presentations and symptoms, family history, body mass index (BMI), iron deficiency, ferritin, serum 25-hydroxyvitamin D, calcium, magnesium, and phosphorus levels. Descriptive, univariate, and multivariate statistical analysis were performed.Results:Mean age (standard deviation [SD] in years) for ADHD and control children were 11.54 (3.83) versus 11.50 (3.62). There were statistically significant differences between ADHD versus control children for vitamin D [16.81 (7.84) vs. 22.18 (9.00) ng/ml], serum iron [82.11 (13.61) vs. 85.60 (12.47) ng/ml], ferritin [36.26 (5.93) vs. 38.19 (5.61) ng/ml], hemoglobin [12.02 (2.13) vs. 12.89 (2.02) g/dL], magnesium [0.82 (0.08) vs. 0.88 (0.06) mmol/L], serum calcium level [2.35 (0.12) vs. 2.39 (0.14) mmol/L], and phosphorous [1.47 (0.30) vs. 1.54 (0.26) mmol/L]. Of total 630 of ADHD children, 116 (18.4%) had severe vitamin D deficiency (<10 ng/ml). Multivariate logistic regression analysis revealed that serum vitamin D level, serum iron, ferritin, serum calcium level, physical activity, nervous behavior, consanguinity, BMI, and child order were considered as the main factors associated with the ADHD after adjusting for age, gender, and other variables.Conclusion:The study indicates that low serum iron, ferritin levels, and vitamin D deficiency may be associated with ADHD.

BackgroundFew epidemiological data on autism spectrum disorders (ASD) exist for Arabic countries. We conducted the first survey of ASD in Qatar, a population with high consanguinity level.MethodsThis cross‐sectional survey was conducted from 2015 to 2018 in Qatar school‐age children (N = 176,960) from national and immigrant families. Children diagnosed with ASD were identified through medical centers and special needs schools. Records were abstracted and supplemented by parental interviews. Additionally, children attending 93 schools were screened; ASD case status was confirmed in random samples of screen‐positive and screen‐negative children. Prevalence was estimated after taking into account different sampling fractions and participation rates at each survey phase.ResultsOne thousand three hundred and ninety‐three children already diagnosed with ASD were identified. Among 9,074 school survey participants, 760 screen‐negative children and 163 screen‐positive children were evaluated; 17 were confirmed to have ASD including five children newly diagnosed. Prevalence was 1.14% (95% CI: 0.89–1.46) among 6‐ to 11‐year‐olds. ASD was reported in full siblings/extended relatives in 5.9% (95% CI: 0.042–0.080)/11.8% (95% CI: 0.095–0.146) families. First‐degree consanguinity in Qatari cases (45%) was comparable to known population levels. Among 844 ASD cases (mean age: 7.2 years; 81% male), most children experienced language delay (words: 75.1%; phrase speech: 91.4%), and 19.4% reported developmental regression. At the time of the survey, persisting deficits in expressive language (19.4%) and peer interactions (14.0%) were reported in conjunction with behavioral problems (ADHD: 30.2%; anxiety: 11.0%). In multivariate logistic regression, ASD severity was associated with parental consanguinity, gestational diabetes, delay in walking, and developmental regression.ConclusionsASD prevalence in Qatar is consistent with recent international studies. The methods employed in this study should help designing comparable surveys in the region. We estimated that 187,000 youths under age 20 have ASD in Gulf countries. This figure should assist in planning health and educational services for a young, fast‐growing population.