Primary Headache Disorders

This observational, case-control study will evaluate differences in serum uric acid and related hematologic and biochemical parameters between adolescents (12-18 years) with primary headache and age-/sex-matched controls without recurrent headaches or chronic medical/psychiatric disorders. Cases will meet International Classification of Headache Disorders, 3rd edition (ICHD-3) criteria verified by a pediatric neurologist after comprehensive clinical assessment. The study will also collect sociodemographic data and anthropometrics to calculate BMI. Primary outcome is the between-group difference in serum uric acid levels at enrollment. Secondary outcomes include group differences in ferritin, creatinine, BUN, complete blood count indices (Hb, WBC, neutrophils, lymphocytes, platelets, MPV), and BMI.