‘Millions’ Prescribed Wrong Dose of Common Drugs

According to updated calculations published this week, over 11 million people in the United States may have been given the wrong prescription for a range of commonly used drugs.

Scientists from the Stanford University School of Medicine in California recently investigated the reliability of so-called pooled cohort equations (PCEs). PCEs help doctors to determine each patient’s overall risk of stroke or heart attack. Assessing cardiovascular risk helps to inform the physician about the exact level of medication that will be both effective and safe. These equations are available as online web tools and smartphone apps, and they are even built into digital medical records.

In recent years, some have called into question the accuracy of PCEs, asking whether the data that they rely on are outdated. If this were found to be the case, patients could potentially be at risk of taking dangerously high or ineffectively low doses of drugs.

Dr. Sanjay Basu, Ph.D., an assistant professor of primary care outcomes research at Stanford published his findings this week in the journal Annals of Internal Medicine.

The first issue was updating the data used to derive the equations. Some of the datasets are relatively old. For instance, one included information from people who were aged 30-62 in 1948. Diet, lifestyle and health risks have changed since those days. The study authors say that, because of the age of this information, people’s risks were being estimated at around 20% higher than they truly were. Dr. Basu notes that “relying on our grandparents’ data to make our treatment choices is probably not the best idea.”

“Another issue the researchers identified was the lack of African-Americans in the datasets. It is now known that cardiovascular risk is significantly higher in the African-American population. So, while many Americans were being recommended aggressive treatments that they may not have needed according to current guidelines, some Americans – particularly African-Americans – may have been give false reassurance and probably need to start treatment given our findings.” – Dr. Sanjay Basu, Ph.D.



To rectify these shortcomings, the researchers added new data to improve the PCEs’ accuracy. The data are currently maintained by the National Institutes of Health (NIH), and they have approved the new and updated equations.

As the PCEs guide medical decisions involving some of the most commonly used prescription drugs – such as aspirins, blood pressure medications, and statins – these changes could potentially save and extend thousands of lives.

My Take:
With all the emphasis on “evidence-based medicine” it’s a little disconcerting to find PCEs use such outdated data. When consulting with other physicians, they always want to see the studies and evidence-based studies are a relatively new development.

However, evidence-based studies (theoretically) only account for a third of clinical decision making. The second third is clinical experience and that’s where I expect the complaints about PCEs developed. What I have experienced as a physician over the course of forty-one years has merit, equal to if not greater than, the limitations of most studies.

The third piece of this equation is patient preference. Your desires for health care, your choices are also equal to (if not greater) than my clinical experience and all evidence-based studies.

The Bottom Line:
Physicians often equate evidenced-based medicine with evidenced based studies. It is vital that they include both their clinical experience and your needs and desires as the patient in any plan of treatment.

Source: June 5, 2018 National Institutes of Health