Methylphenidate prescriptions in the city of Cologne: Overrepresentation of privately insured patients - Results of an analysis based on prescription data

Background: Attention-deficit/hyperactivity disorder (ADHD) is a chronic psychiatric disorder which most commonly affects children and adolescents. Treatment with methylphenidate (MPH) entails a dependency risk as MPH is a psychotropic drug. In Germany, according to pharmaco-epidemiological studies based on figures provided by the general health insurance scheme, MPH prescriptions have increased 40-fold over the past decade. Objective: We aimed to investigate MPH prescriptions issued by medical practitioners in the city of Cologne with a special focus on prescription practices and the proportion of MPH prescriptions issued for privately insured patients. Method: This is a descriptive study. The database consisted of all registered MPH prescriptions during the first two quarters of 2003 and included 2729 prescriptions issued by hospital and practice-based medical practitioners. Results: 23% of all MPH prescriptions were issued on private prescriptions, indicating an overrepresentation of privately insured patients who generally make up about 10 % of all insured persons in Germany. There was a high frequency of once-only prescriptions: 28% of all prescriptions fell into this category. In addition, prescribed daily doses were often lower or higher than age-specific recommended mean daily doses. Conclusion: The study provided evidence of inappropriate care patterns concerning MPH. A marked socio-economic gradient exists with regard to MPH prescriptions.