Metric 35

Average Number of Concurrent Medications Per Older Patient

Metric Category: Appropriateness

About the Metric


The average number of concurrent medications prescribed per older patient. 


The total number of medication prescriptions in the US has increased by 85% over the last two decades. In particular, prescription drug use in patients aged 65 years or older has increased dramatically. Older patients are at a particularly high risk for drug-related injuries such as falls and medication interactions. Polypharmacy has been associated with increased medical cost, increased hospitalizations, and increased mortality.

Metric Ratings

Expert Consensus
Clinician Buy-in
Economic Impact
Reduction in Avoidable Harm
Applicability to Medicare Data
Applicability to Medicaid

Applicable to EHR Data?

Requires Pharmacy Data?

How It Works


The total number of concurrent medications summed across the patients from the denominator. For each patient, the number of concurrent medications is defined as the maximum number of concurrent medications in use on any day during the study period. The fill date and days of supply should be used to calculate the days of medication use. Overlapping days of the same medication should be credited by shifting the start date of the subsequent prescription to the day after the previous prescription was completed. Medications of the same generic name and different dosage strength should be considered the same medication. Only prescription medications with at least 30 days of supply should be included.


The number of patients aged 65 years or older who filled any prescription by a given primary care physician during the study period. 

Inclusion Criteria

All patients aged 65 years or older who filled any prescription during the study period. 

Exclusion Criteria

Patients who had an organ transplant in the past, are taking transplant immunosuppression medications, chemotherapy, or have HIV. 



GAM™ Thresholds

Minimal number of patients required in the denominator Clinical threshold of what constitutes a pattern of concern Clinical threshold of what constitutes an outlier
11 6-7.7 >7.7