In the US, lack of adherence to medicine prescriptions has become an epidemic, raising concerns of health experts. “Studies have consistently shown that 20% to 30% of medication prescriptions are never filled, and that approximately 50% of medications for chronic disease are not taken as prescribed,” according to a review.

The Centres for Disease Control and Prevention (CDC) have estimated that the issue of non-adherence to prescribed medications causes at least 10% of hospitalisations, 30% to 50% of chronic disease treatment failures and approximately 125,000 deaths annually.

Despite the fact that it is potentially 100% preventable, most people still choose to skip their medications, which costs the US healthcare system between USD100 billion and USD289 billion each year.

The unseen costs behind non-adherence

One of the reasons why performance of new drugs released into the market does not always correspond with positive results achieved from clinical trials, as patients become slack in taking their medication.

“Drugs don’t work in patients who don’t take them,” said former Surgeon General C. Everett Koop.

Besides, there are cases where many patients do not get better, suffer unexpected relapses or even die when they do not follow the drug prescriptions given.

Studies have also shown that a third of kidney transplant patients do not take their anti-rejection medications, 41% of heart attack patients do not take their blood pressure medications and 50% of children with asthma either do not use their inhalers or use them inconsistently.

“When people don’t take the medications prescribed for them, emergency department visits and hospitalisations increase and more people die,” said Bruce Bender, co-director of the Centre for Health Promotion at National Jewish Health in Denver.

“Non-adherence is a huge problem, and there’s no one solution because there are many different reasons why it happens,” said Bender.

Difficult to address due to many factors involved

“There’s a societal push to do things naturally,” according to cardiologist Lisa Rosenbaum of Brigham and Women’s Hospital in Boston. “The emphasis on diet and exercise convinces some people that they don’t have to take medications.”

When she asked her heart attack patients why they were not taking their medications, there were various responses. Some patients said they did not want to be associated with sickness, whereas some were reluctant to take their medication as they are view them as “unnatural”. Another common response was that they were “not a pill person”.

Cost is also a major factor. According to Bender, “when the co-pay for a drug hits USD50 or more, adherence really drops.”

Hence, when patients were offered free medications, adherence improved by 6% with 11% fewer heart attacks and strokes, revealed Dr William Shrank, chief medical officer at the University of Pittsburgh Health Plan.

“There are so many reasons patients don’t adhere — the prescription may be too complicated, they get confused, they don’t have symptoms, they don’t like the side effects, they can’t pay for the drug, or they believe it’s a sign of weakness to need medication,” said Shrank.

“This is why it’s so hard to fix the problem — any measure we try only addresses one factor,” he added.

Strategies to reinforce adherence to medication

Despite the challenges, Shrank said there is still hope for improvement. For example, multiple drugs could be combined into one pill or packaged together, or dosing could be simplified.

Doctors and pharmacists could also adopt digital technology to communicate with patients and reinforce the importance of keeping up with their medications. While issuing a prescription, doctors should also explain about the potential side effects as patients may be afraid of adverse effects.

Kimberly DeFronzo, a Consumer Safety Officer in FDA's Centre for Drug Evaluation and Research, remarked that it is important to take the medicines as prescribed in order to get the best results, especially now that there are many antibiotic-resistant pathogens.

Thus, efforts from healthcare professionals as well as patients are important to avoid such preventable causes of morbidity. MIMS

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