Attention deficit, hyperactivity disorder (ADHD) is familial and highly heritable. Several candidate genes involved in neurotransmission have been identified, however these confer minimal risk, suggesting that for the most part, ADHD is not caused by single common genetic variants. Advances in genotyping enabling investigation at the level of the genome have led to the discovery of rare structural variants suggesting that ADHD is a genomic disorder, with potentially thousands of variants, and common neuronal pathways disrupted by numerous rare variants resulting in similar ADHD phenotypes. Heritability studies in humans also indicate the importance of epigenetic factors, and animal studies are deciphering some of the processes that confer risk during gestation and throughout the post-natal period. These and future discoveries will lead to improved diagnosis, individualized treatment, cures, and prevention. These advances also highlight ethical and legal issues requiring management and interpretation of genetic data and ensuring privacy and protection from misuse.

Introduction:In this cross-sectional study, we aimed to determine the prevalence and characteristics of chronic ocular itch in an outpatient ophthalmology and optometry clinic.Methods:Four hundred patients from an outpatient ophthalmology and optometry clinic were enrolled. The presence and characteristics of chronic ocular itch were assessed by a questionnaire. Data regarding ophthalmologic, dermatologic, and systemic conditions as well as current medications were extracted from medical records.Results:Chronic ocular itch was present in 118 (29.5%) of 400 participants. Chronic ocular pruritus was significantly more prevalent in females [P=0.015; odds ratio (OR)=1.8; 95% confidence interval (CI), 1.1–2.8] and was significantly associated with the presence of allergic conjunctivitis [51.8% (n=45); P<0.001; OR=5.0; 95% CI, 3.0–8.3], dry eye syndrome [40.1% (75); P<0.001; OR=2.6; 95% CI, 1.7–4.1], blepharitis [43.8% (n=21); P=0.021; OR=2.0; 95% CI, 1.1–3.8], and atopic dermatitis [50.0% (n=10); P=0.023; OR=2.6; 95% CI, 1.1–5.8]. Chronic ocular itch was not significantly associated with systemic conditions, or the use of prescribed ophthalmologic medications.Discussion:Chronic ocular itch is common and may be related to ophthalmologic or dermatologic pathologies. The present findings highlight the importance of identifying and managing this uncomfortable symptom that may negatively impact the quality of life and sleep of affected patients.

No abstract

No abstract

No abstract