July 3, 2014 — A study of children in Denmark had found higher rates of heart problems among children who take Ritalin (methylphenidate), or other stimulant drugs for the treatment of attention deficit hyperactivity disorder (ADHD).
The results of the study were based on data from 714,000 children, including 8,300 who were diagnosed with ADHD. All of the children were born in Denmark between 1990 and 1999.
Researchers estimated that children with ADHD on stimulants were 2.2-times as likely to have a cardiovascular diagnosis compared to children with ADHD who did not use stimulant drugs. Surprisingly, higher doses were not associated with more heart problems.
The incidence of cardiovascular side effects appears to be low. There were only 111 diagnoses among 8,300 children with ADHD, for an overall incidence of 0.17% and a yearly risk of less than 1%.
Adverse events reported in the study include:
- arrhythmias (23%)
- hypertension (8%)
- ischemic heart disease (2%)
- pulmonary heart disease (<1%)
- cardiac arrest (<1%)
- heart failure (2%)
- heart disease caused by rheumatic fever (2%)
- heart disease not otherwise specified (14%)
- cerebrovascular disease (9%)
- cardiovascular disease not otherwise specified (40%)
In the last decade, many experts have raised concern about the over-diagnosis of ADHD among American children. The most popular stimulant ADHD medication, Ritalin (methylphenidate), already carries warnings about the possible risk of heart problems, priapism, and other severe side effects.