Adults with attention-deficit/hyperactivity disorder (ADHD) are at higher risk of developing cardiovascular diseases than those who do not have the condition, according to research from Karolinska Institutet and Örebro University, in Sweden.
ADHD is a common neurodevelopmental disorder, with a global prevalence of around 2.5% in adults. The condition affects cognitive behaviour. People with ADHD can seem restless, may have trouble concentrating, and may appear to act on impulse.
ADHD often exists alongside other psychiatric and physical conditions, many of which have been liked to increased susceptibility to cardiovascular diseases. However, few previous studies have researched whether ADHD is independently associated with overall and specific cardiovascular diseases.
The findings are published in the journal World Psychiatry.
Adults with ADHD are twice as likely to suffer from cardiovascular diseases
In this study, the researchers sought to find correlations between ADHD and 20 different cardiovascular diseases. Importantly, this study considered ADHD separately from other known risk factors such as obesity, type 2 diabetes, smoking, sleep problems, and mental disorders.
“We found that adults with ADHD were more than twice as likely to develop at least one cardiovascular disease, compared with those without ADHD,” said the study’s first author Lin Li, a postdoctoral researcher at the Department of Medical Epidemiology and Biostatistics, Karolinska Institutet.
“When we accounted for other well-established risk factors for cardiovascular diseases, the association weakened but still remained significant, which indicates that ADHD is an independent risk factor for a wide range of cardiovascular diseases.”
The research team analysed data from the national registry of Sweden, which contains information on over five million people, 37,000 of whom have ADHD. After 12 years, 38% of individuals with ADHD had been diagnosed with at least one cardiovascular disease, compared to 24% of those without ADHD.
Men with ADHD are at greater risk
People with ADHD were found to have an elevated susceptibility to all cardiovascular diseases and especially high risk of cardiac arrest. The association was found to be stronger in men than in women. Contributing factors such as eating disorders and substance abuse were also found to significantly increase the risk of cardiovascular disease in people with ADHD.
The researchers note that due to the study’s observational nature, the findings cannot establish a causal relationship between ADHD and cardiovascular diseases.
“Clinicians need to carefully consider psychiatric comorbidity and lifestyle factors to help reduce the risk in individuals with ADHD, but we also need more research to explore plausible biological mechanisms, such as shared genetic components for ADHD and cardiovascular disease,” said the study’s last author Henrik Larsson, Professor at the School of Medical Sciences, Örebro University, and affiliated researcher at Karolinska Institutet.
The researchers also acknowledge that the study had some limitations, including a lack of data on some lifestyle-related factors. Information on factors such as diet and physical activity may have affected the findings.