Medication use by seniors is a concern for physicians and for the public.  Seniors comprise 1% of the population, but account for 25% of prescription drug use.  Many seniors are taking multiple medications, and as the population ages the number of people taking a large number of medications will increase.  Medications are usually helpful, but can be associated with a variety of problems including falls, cognitive impairment and hospital admission.  One aspect that may increase the risk of adverse drug reactions is the prescribing physician’s knowledge of the medications the patient is already taking.  This issue was recently studied at the Geriatric Day Hospital at St. Mary’s of the Lake.  Patients attend the Day Hospital twice weekly for rehabilitation and assessment and one of the major activities at the program is the review and evaluation of patients’ medications.  Because of this role, the Day Hospital was chosen as the site to study the accuracy of family physicians’ knowledge of patients’ medications and to determine whether a lack of knowledge was associated with potential adverse drug reactions.

Over a one-year period, 120 people living independently in the community and attending Day Hospital were enrolled in the study.  The pharmacist at the Day Hospital did a thorough assessment to try to determine the medications the patient had taken in the last month, including over the counter and prescribed medications.  This sometimes involved discussions with family members, caregivers and the patient’s pharmacist.  The family physician was then contacted to get the patient’s medication list as documented in the chart.  The two lists were then compared and any discrepancies between the lists recorded as additions (the patient was taking something not on the MD’s list) or deletions (patient not taking something on the MD’s list).  Any differences in dosage or timing were also noted.

To determine whether these medication “mix-ups” could have a negative effect on the patient, any addition or deleted medication was reviewed to see if it fulfilled the criteria for being “inappropriate” to be used by an older person.  This was done using a previously published list of drugs to avoid in the elderly.  To see if the medication mix-ups increased the potential risk of drug interactions, a computer program was used to identify any possible interactions in the patient and physicians’ lists.

The average number of medications taken by patients in the preceding month was 10.5 , including over-the-counter medications (OTC’s).  One hundred and fifteen of 120 patients had at least one difference between the medications they were actually taking and the list in the family physician’s chart. More than 6 discrepancies between lists were found in 37% of patients.  The majority of these differences involved OTC’s, which is understandable as the patient may take these without informing the doctor. Unfortunately, nearly 40% of prescribed medications had some difference between how or what the patient was taking and what the doctor thought they were taking.

The most common type of mix-up was the addition of a medication.  This may have occurred when the patient saw another physician or the medication use might have never been documented accurately by the family physician.  Only 10% of drug mix-ups were medications judged to be “inappropriate”.  However, there was an increased risk of potential drug interactions in the list of what the patient was actually taking compared to the risk in the list from the family physician

What are the important messages from this study?  The first thing is to be aware that it is very hard for the family physician to keep up to date with which medications their older patient is taking.  It is, therefore, very important that patients try to keep an up-to-date list and to inform the physician of changes made by specialists or other physicians.  Another important point is that over the counter medications, including herbal preparations, hould be viewed as potentially harmful and that the family doctor should be made aware of frequent use of any such product.  Regular review and visual inspection of medications should be considered by family physicians for their frail elderly patients.  The use of the  “brown bag review” where patients are asked to bring all of their medications to the doctor’s office can be helpful.  Keeping patients knowledgeable about their own medication schedules and health issues is a reasonable place for health professionals to start to decrease the risk from this problem.

Dr. Chris Frank is a physician within the Division of Geriatric Medicine.