Review: Medicinal Cannabis Use in Denmark

In recent years we have witnessed a tremendous increase in the use of cannabis for medicinal use with a parallel increase in public demand for safe access to medicinal cannabis.

In 2016, the Danish parliament agreed to initiate a medicinal cannabis pilot program to create a secure framework for medicinal cannabis within the health care system. The initial pilot program was of four years duration but has now been extended. At the initiation of the pilot program, the Danish Medicinal Agency recommended cannabis for four patient groups. Chronic pain (with neuralgic component), multiple sclerosis, spinal cord injury, and side effects from chemotherapy. The pilot program has led to a more open debate on the use of medicinal cannabis. It has become clear that the use of medicinal cannabis has spread beyond the indication recommended by the Danish Medicinal Agency. 

A recent, fascinating paper (Kvamme, S.L. et al. 2021) has investigated the consumption and motives for the use of medicinal cannabis in the Danish population. The study was in the form of an electronic questionnaire made available online to users of medicinal cannabis. Questions were related to the characterization of subjects in the trial, motivation for use, duration and frequency of use, method of administration, evaluation of experienced effects, and adverse effects. The main results are summarized below:

  1. Responders were fairly evenly distributed among the different regions in Denmark relative to their populations. Also, responders represented a broad socioeconomic segment of the Danish people. The majority of responders were women (62.6%).
  2. The most common form of cannabis was CBD oil (65%), followed by “hash, pot or skunk” (36.2%) and THC oil (25.3%). Approximately one-third (37.8%) used CBD oil only. Cannabis oil was the most common form of intake (56.8%), especially among women.
  3. The most frequent conditions treated with medical cannabis were pain (32.0%), sleep disturbances (27.5%), stress (23.7%), anxiety (19.6%), and depression (19.6). Causes for pain were not well defined, but the total incidence of arthritis among the responders was 34.1%: osteoarthritis (22.7%), rheumatoid arthritis 8.1%, and psoriatic arthritis (3.3%). Only 7.1% used medicinal cannabis for cancer or cancer-related treatment. A majority (52.8%) used medicinal cannabis to replace a prescribed drug.
  4. Only 27.8% had asked their GP for a prescription for medicinal cannabis, and a minority (8.4%) of the respondents had a prescription for cannabis.
  5. Approximately 60% of the responders had used medicinal cannabis for more than a year, and 75.4% used cannabis 6-7 days a week.

Although the study’s primary aim was related to characterizing patterns of use and motives of use of medicinal cannabis, questions on the efficacy of cannabis were part of the questionnaire. Based on different rating scales, patients rated the perceived effectiveness of medicinal cannabis and its effect on their daily living.

The reported mean effect across all medical conditions was – based on a rating scale where 3.0 was “large improvement” – 2.82 (SD 0.92), meaning that the average responder had an obvious beneficial effect from cannabis. The highest mean benefit was on reduction in alcohol dependence (mean 3.25), the dependence on hard drugs (mean 3.13), and sleep disturbances (mean 3.16). Among responders with sleep disturbances, 70.1% indicated a mean of 4.3 hours of sleep without medicinal cannabis and 7.3 hours of sleep using cannabis. An additional 20.7% reported no improvements in hours slept but an improvement in sleep quality. A total of 87.5% agreed/strongly that the use of medicinal cannabis had a positive effect on their ability to handle practical chores in their daily life.

Side-effects were minimal, with “dryness of mouth” (22.2%) and “being high” (16.2%) as the two most common complaints.

It should be noted that there are many biases in the study when evaluating the efficacy of medicinal cannabis (no control group, bias in recruitment, etc.). However, it is well known that placebo effects tend to disappear with time. Furthermore, lack of adherence to prescribed drugs is a significant clinical problem, and we know that the main reason for the lack of adherence is the perceived lack of efficacy of the prescribed drug. The fact that the majority of the user have taken medicinal cannabis for more than a year with almost daily dosing support that the reported beneficial effect of using medicinal cannabis cannot be dismissed lightly.