Despite Statistics Canada reporting that a small portion of older Canadians used cannabis in 2015 (1.6 % of adults over the age of 50)1, with the recent legalization of cannabis and the transition of a significant cohort of the Baby Boomer generation into retirement, it is anticipated that levels of cannabis use among adults over the age of 50 will increase.
The decreasing stigma around cannabis use, as a result of a nationwide Health Canada public education program and continued ongoing mainstream media coverage, will also affect use among older Canadians. Additionally, older adults, who are often living with multiple medical ailments, are at significant risk of self-medicating with legalized cannabis, often relying on information supplied by marketing campaigns from suppliers that are based on scant or low-quality scientific evidence or research.
Older adults commonly cite medical issues as the reason for their cannabis use. Older Canadians are likely to use cannabis to relieve chronic pain, reduce anxiety or depression, and as a sleep aid. While there has been a number of research studies on the medicinal uses of cannabis, the evidence tends to be of mid- to low quality and often vulnerable to bias.2
Similar to other populations, older adults are also at an increased risk of cannabis use disorder with frequent use. Unfortunately, diagnosing cannabis use disorder within this group can be challenging. Many of the effects of cannabis use can be misdiagnosed as symptoms of dementia, as studies have shown that cognitive changes due to cannabis often persist long after stopping chronic use. It is important for practitioners to take a thorough history, gain collateral information from family members, and explore the patient’s reasons for starting cannabis use in the first place, to determine an appropriate diagnosis.
Additionally, substance use among seniors is often associated with other mental illnesses including depression and generalized anxiety disorder, and can be exacerbated by psychosocial issues often experienced by older adults such as loneliness, bereavement and chronic illness and/or disability.3
Practitioners should also take note of potential interactions with other medications, which symptoms can include: an increased risk of cognitive impairment or confusion, mood altering properties, an increased risk of arrhythmias, and light-headedness and dizziness (leading to an increased risk of falls).
There may also be an increased incidence risk of cannabis toxicity with this population, as self-medicating behaviour can lead to a lack of dosage control. Additionally, this risk may also be exacerbated by the upcoming legalization of edible cannabis products in Canada, which will occur by October 2019. Therefore, is it very important that practitioners provide education around cannabis intoxication and impaired driving with their older adult clients.
Cannabis toxicity in the elderly can often have a different clinical presentation than in the general population. Older adults may experience more severe effects from mild cannabis doses, with higher risks associated, such as changes in walking and gait, changes in blood pressure and arrhythmias, and even loss of consciousness or coma.
More detailed clinical guidelines for health practitioners are currently being developed by the Coalition for Seniors’ Mental Health and are due to be published sometime in early 2019.
1 Statistics Canada 2015
2 Healthydebate.ca (https://healthydebate.ca/2017/06/topic/marijuana-seniors)