Study finds heart-related side effects of ADHD drugs, yet benefits outweigh risks

New Delhi: A new study has found that ADHD medications could have cardiovascular side effects, such as increased blood pressure and heart rate, even as the benefits were found to outweigh the risks of taking these drugs.

Published in The Lancet Psychiatry journal, the study is the largest and most comprehensive analysis of the cardiovascular effects of drugs used to manage the neurodevelopmental disorder, researchers said.

"When it comes to taking any medication, risks and benefits should always be assessed together. We found an overall small increase in blood pressure and pulse for the majority of children taking ADHD medications," lead author Samuele Cortese, University of Southampton, UK, said.

A patient with ADHD suffers from short attention spans and can display hyperactivity or restless behaviour. Symptoms are usually diagnosed in childhood, which can sometimes continue into adulthood.

"Other studies show clear benefits in terms of reductions in mortality risk and improvement in academic functions, as well as a small increased risk of hypertension, but not other cardiovascular diseases. Overall, the risk-benefit ratio is reassuring for people taking ADHD medications," Cortese said.

The researchers said that there have been concerns regarding the drugs' cardiovascular side effects, and that data in this aspect is unclear.

They added that those with existing heart conditions should discuss the side effects of ADHD medications with a cardiologist before starting treatment.

For the analysis, the team looked at the results of over 100 trials involving about 22,700 children, adolescents and adults with ADHD. The randomised controlled trials assessed the effects of drugs, including amphetamines, atomoxetine and bupropion, on pulse and blood pressure.

The researchers found that all ADHD medications, except guanfacine, were generally associated with small increases in blood pressure, heart rate and ECG parameters.

"Amphetamines, atomoxetine, lisdexamfetamine, methylphenidate and viloxazine led to increments in haemodynamic values (blood pressure and cardiac output) in children and adolescents, adults, or both," the authors wrote.

The study found no significant differences between stimulants, including methylphenidate and amphetamine, and non-stimulants (atomoxetine and viloxazine) with regard to their effects on blood pressure and heart rate.

Stimulants are fast-acting drugs that boost the levels of brain chemicals — dopamine and norepinephrine — crucial for regulating mood, attention and motivation.

"Practitioners should monitor blood pressure and pulse in patients with ADHD treated with any pharmacological intervention, and not stimulants only," the authors wrote.

Prevalence of ADHD in the world is estimated to be about 8 per cent among children and teenagers, with boys twice as likely to be diagnosed than girls, according to an article published in the Journal of Indian Association for Child and Adolescent Mental Health in February.

In India, prevalence can range from about a per cent to up to almost 30 per cent, with higher rates among boys (9.4 per cent) than girls (5.2 per cent), it said.