Variability and trends in the consumption of drugs for treating attention-deficit/hyperactivity disorder in Castile-La Mancha, Spain (1992-2015).

INTRODUCTION: Attention-deficit/hyperactivity disorder (ADHD) is one of the most common behavioural disorders of childhood; its prevalence in Spain is estimated at 5-9%. Available treatments for this condition include methylphenidate, atomoxetine, and lisdexamfetamine, whose consumption increases each year.

MATERIAL AND METHODS: The prevalence of ADHD was estimated by calculating the defined daily dose per 1,000 population per day of each drug and the total doses (therapeutic group N06BA) between 1992 and 2015 in each of the provinces of Castile-La Mancha (Spain). Trends, joinpoints, and annual percentages of change were analysed using joinpoint regression models.

RESULTS: The minimum prevalence of ADHD in the population of Castile-La Mancha aged 5 to 19 was estimated at 13.22 cases per 1,000 population per day; prevalence varied across provinces (p<.05). Overall consumption has increased from 1992 to 2015, with an annual percentages of change of 10.3% and several joinpoints (2000, 2009, and 2012). methylphenidate represents 89.6% of total drug consumption, followed by lisdexamfetamine at 8%.

CONCLUSIONS: Analysing drug consumption enables us to estimate the distribution of ADHD patients in Castile-La Mancha. Our data show an increase in the consumption of these drugs as well as differences in drug consumption between provinces, which reflect differences in ADHD management in clinical practice.