Hypertension: Could long-term use of ADHD meds increase risk?

Attention deficit hyperactivity disorder (ADHD) is a neurodevelopmental disorder. It has subtypes, and doctors are not entirely sure of the precise cause of ADHD.

The CDC estimates that 9.8% of children between the ages of three and seventeen have ever been diagnosed with ADHD in the United States. Children with ADHD may also have other conditions, such as autism spectrum disorder or anxiety.

ADHD can involve several behavioral components. Someone with ADHD may have difficulty in paying attention, act without thinking, and find it hard to sit still. The specifics can vary from person to person.

Treatment for ADHD can involve the use of certain medications that can help improve some behaviors and symptoms. Common medications include stimulants and non-stimulants. Sometimes, someone with ADHD may be on more than one medication to help with ADHD symptoms.

Researchers in the current study wrote that “[p]harmacological therapy, including both stimulants and nonstimulants, is recommended as the first-line treatment for ADHD in many countries. The use of ADHD medication has increased greatly in both children and adults during the past decades.”

Research is ongoing about the potential long-term effects of ADHD medication use. Gathering more data in this area can help doctors make informed decisions when prescribing ADHD medications.

This case-control study was conducted in Sweden. Researchers included 278,027 participants. Participants were ages 6–64 and had either received an ADHD diagnosis or were taking ADHD medication.

They looked at the timeframe of ADHD medication use, up to 14 years, and the incidence of several cardiovascular diseases, such as abnormal heart rhythms, heart failure, high blood pressure, and arterial disease. The researchers collected data via the National Inpatient Register, which records diagnoses, and the Swedish Prescribed Drug Register, which records data on dispensed medications.

In their analysis, they found that individuals taking ADHD medication were at a higher risk for cardiovascular disease, particularly within the first three cumulative years of taking ADHD medication.

After this, the associated risk remained more stable. Researchers found similar results among men and women and among children and adults.

Researchers further found that participants taking ADHD medication were particularly at risk for high blood pressure and arterial disease. However, the risk related to several other cardiovascular diseases was not statistically significant.

Dr. Keith C. Ferdinand, professor of medicine at the Tulane University School of Medicine, who was not involved in the study, noted to Medical News Today:

“This well-done, long term study did not did not observe any statistically significant increased risk for arrhythmias, heart failure, ischemic heart disease, thromboembolic disease, or cerebrovascular disease and should inform the public that these life threatening conditions were not clearly revealed as a driver of risks. Hence, it is reasonable to understand the real possibility of increased risk of hypertension and arterial disease, especially associated with stimulant medication use without suggesting that all ADHD medications, even used briefly, should always be avoided.”

Stimulant vs. non-stimulant medication for ADHD

The results also suggest that the risk for cardiovascular disease may be higher when taking stimulants rather than non-stimulants. The research points to the importance of weighing the risks and benefits of taking ADHD medication long-term.

Study authors Dr. Le Zhang and Dr. Zheng Chang explained to MNT:

“This longitudinal observational study found long-term exposure to ADHD medications was associated with an increased risk of CVDs [cardiovascular diseases], especially hypertension and arterial disease.”

“Clinicians should be vigilant in monitoring signs and symptoms of cardiovascular diseases, particularly among those receiving higher doses [of ADHD medications]. Treatment decisions, as always, should be based on careful[ly] weighing potential benefits and risks at individual patient level, rather than simple one-size-fits-all recommendations.”
— Study authors Dr. Le Zhang and Dr. Zheng Chang

This research does have certain limitations. First, it cannot prove that ADHD medication causes any cardiovascular disease problems.

It also only included individuals from one country, which could indicate the need for more diverse studies in the future. Future research can also have larger sample sizes.

Researchers note that there’s the possibility that there could have been some cases of cardiovascular disease that doctors had not diagnosed. They also note that there could have been exposure misclassification if participants did not take their medications the way medical professionals prescribed.

There is also the possibility of residual confounding, and results could have been affected by time-varying confounders. The research also did not look at the risk for cardiovascular disease among individuals who already had cardiovascular disease.

Study authors Dr. Le Zhang and Dr. Zheng Chang explained some components of future research to MNT:

“The current study did not examine the risk of CVD among individuals with pre-existing CVD. Further research needs to be done to examine the potential risks among individuals with pre-existing CVD. Individuals with pre-existing CVD represent a distinct clinical group that requires careful monitoring; thus, evaluating the risk among them necessitates a different study design that carefully considers the potential impact of prior knowledge and periodic monitoring.”