Nearly one in four Ontario seniors using mental health drugs

There have been significant changes in the use and cost of mental health drugs for elderly Ontarians, a new study from the Institute for Clinical Evaluative Sciences (ICES) shows, with almost one quarter of Ontario seniors now using at least one mental health-related medication.

“With many new and more expensive mental health drugs coming on the market over the last ten to twelve years, questions are now being raised about the cost-effectiveness of these medications,” said lead author and ICES senior scientist Dr. Muhammad Mamdani. “However, before we can conduct any comprehensive cost-effectiveness analyses, we need to know more about how these drugs are being used by elderly Ontarians and how much they are costing our healthcare system.”

In order to examine this issue, researchers tracked more than 1.4 million Ontarians aged 65 years or older between 1993 and 2002 that were prescribed antidepressants, antipsychotics, mood stabilizers, benzodiazepines (anti-anxiety medications), or acetylcholinesterase inhibitors (AChEIs) for Alzheimer’s disease. Within this study group, researchers assessed overall use, total and per person number of prescriptions dispensed, relative prescription market share for each drug group, and total and per person prescription cost. To estimate the prevalence of current users of mental health-related drugs among the older adult population, the study period was divided into quarterly intervals.

Overall Results:

• The prevalence of mental health-related drug users increased from 21% of the elderly (265,988 seniors) at the beginning of 1993, to 24% (361,753 seniors) by the end of 2002.
• These increases were associated with a 210% increase in total expenditures on mental health-related drugs from approximately $32 per Ontario senior ($40 million in total) in 1993 to $99 per Ontario senior ($149 million in total) in 2002.

Results by Drug Group:

Antidepressants

• The use of antidepressants among the older adult population increased from 6% in 1993 to 11% in 2002.
• The quarterly cost of antidepressant prescriptions more than doubled over the study period, from $50 to $105 per antidepressant user.
• Prescription costs for antidepressants accounted for 42% of all mental health-related drug costs in the elderly by the end of 2002.

Antipsychotics

• Antipsychotic use among the older adult population increased from 2% in 1993 to 3% in 2002.
• The quarterly cost of antipsychotics increased by approximately 490% over the study period from $33 to $194 per antipsychotic user, mainly because of the introduction of newer, more expensive atypical antipsychotics in the late 1990s.
• Prescription costs for antipsychotics accounted for 21% of all mental health-related drug costs in the elderly by 2002.

Mood stabilizers

• Mood stabilizer use among the older adult population increased from 0.7% in 1993 to 1% by the end of 2002.
• The quarterly cost of mood stabilizers per user of these drugs increased 82%, from approximately $43 at the beginning of 1993 to $78 by the end of 2002.
• Prescription costs for mood stabilizers accounted for 4% of all mental health-related drug costs in the elderly by the end of 2002.

Benzodiazepines

• Benzodiazepine use decreased from approximately 17% in the beginning of 1993 to 15% by the end of 2002.
• Quarterly benzodiazepine prescription costs per user decreased 34%, from approximately $23 per benzodiazepine user in the beginning of 1993 to $15 by the end of 2002.
• Prescription costs for benzodiazepines decreased from 49% of all mental health-related drug costs in the elderly in 1993 to 9% in 2002.

AChEIs

• AChEI use increased from 0.1% in the second quarter of 1999 (the date they were added to the Ontario Drug Benefits formulary), to 1.5% by the end of 2002.
• The quarterly cost of AChEI prescriptions per user was fairly stable at approximately $450 per AChEI user throughout the study period.
• Although AChEIs represented only 5.7% of all mental health-related drug prescriptions dispensed to the elderly in 2002, they represented approximately 25% of all mental health-related drug costs.

“More and more, guidelines to treat seniors with mental health disorders are calling for earlier recognition of disorders, more aggressive use of drugs, and an expansion of the clinical reasons for using these medications, to include milder forms of illness such as minor depression and mild cognitive impairment,” said Dr. Mamdani.

“However, with the increases in use and cost shown in our study, clearly we also need to balance our enthusiasm for these drugs with the assurance that they are producing optimal benefits for every elderly patient who uses them.”

The study, “Mental health related drug utilization among the older adult population: prevalence, trends and cost”, is in the October 2005 issue of the American Journal of Geriatric Psychiatry.

Author affiliations: ICES (Drs. Mamdani and Rochon); Sunnybrook and Women’s College Health Sciences Centre Department of Psychiatry (Drs. Rapoport, Shulman and Herrmann); Faculty of Pharmacy (Dr. Mamdani), Faculty of Medicine (all authors), University of Toronto; Baycrest Centre for Geriatric Care (Dr. Rochon).

ICES is an independent, non-profit organization that uses population-based health information to produce knowledge on a broad range of healthcare issues. Our unbiased evidence provides measures of health system performance, a clearer understanding of the shifting healthcare needs of Ontarians, and a stimulus for discussion of practical solutions to optimize scarce resources. ICES knowledge is highly regarded in Canada and abroad, and is widely used by government, hospitals, planners, and practitioners to make decisions about care delivery and to develop policy.

FOR FURTHER INFORMATION, PLEASE CONTACT:

• Julie Argles
• Media Relations Officer, ICES
• (416) 480-4780 or cell (416) 432-8143