UK data links medical cannabis to improvements in ADHD patients

New findings from the UK link medical cannabis treatment to improvements in quality of life among ADHD patients.

A new study using data from the UK Medical Cannabis Registry suggest that patients prescribed cannabis-based medicinal products (CBPMs) for attention-deficit/hyperactivity disorder (ADHD) showed improvements in sleep, anxiety and overall quality of life.

ADHD is one of the most common conditions for which medical cannabis is prescribed in the UK, closely following chronic pain and anxiety disorders. 

The prevalence of neurodevelopmental conditions has also been on the rise in recent years, with 2.6 million people in the UK now diagnosed with ADHD. 

A total of 68 patients enrolled on the registry through a private cannabis clinic, Sapphire Clinics, were included in the study of which 55 were male and 13 female.

The majority of participants (81%) had been consuming cannabis medicinally prior to accessing the treatment on prescription. Just over half (56%) were prescribed flower alone, with 6% prescribed sublingual oils and 38% prescribed a combination of both. 

Patient-reported outcomes measures were assessed at one, three, six and 12 months after beginning treatment using standardised questionnaires to determine quality of life, anxiety and sleep scores. 

READ MORE: Rise in patients with ‘unmet’ mental health needs seeking medicinal cannabis

Improvements in anxiety severity and sleep were identified at all time points, with clinically significant improvements in generalised anxiety (GAD-7) scores observed in 50% of patients at 1 month, 42.65% at 3 months, 39.71% at 6 months and 26.47% at 12 months.

Clinically significant improvements in quality of life were found at one, three and six month assessments. 

Researchers also noted a reduction in use of other ADHD medications among the patient group. Prescription of lisdexamfetamine was reduced by 38% during the study, methylphenidate by 15% and dexamfetamine by 14% – all of which can cause negative side-effects, according to the authors.

Adverse events from CBPMs were reported by 11 participants and most of these were described as moderate. 

“This case series is the first of its kind in assessing the clinical outcome of patients from the UKMCR with a primary diagnosis of ADHD prescribed CBMPs for up to 12 months,” the authors state.

“These results suggest that CBMPs may play a role in alleviating symptoms and co-morbid anxiety and sleep disruption associated with ADHD, though these are preliminary findings. CBMPs were well-tolerated throughout this study and the majority of patients (83.82%) did not report any adverse events.”

They add that due to the limitations of the study a ‘causal relationship cannot be drawn’ from the findings and further research, including randomised controlled trials (RCTs) should be carried out on the potential of cannabis-based medicines in ADHD. 

They conclude: “The findings from this study guide further investigation to assess the therapeutic efficacy and long-term safety profile of CBMPs. Comparative analysis should be performed on patients in the UKMCR for future evaluations, and importantly, it is essential to conduct high-quality RCTs for the treatment of ADHD whilst controlling for potential confounding factors.”