One third to a half of all US patients do not take their medications as prescribed, and this is costing the nation $290 billion - 13% of total health expenditures - every year, says a new report.

Such poor levels of compliance are fuelling - and are fuelled by - the rising tide of chronic disease, says the report, by researchers at the New England Healthcare Institute (NEHI). In general, people with chronic illnesses are worse at taking their medications as prescribed than those with acute conditions, and medication persistence – the length of time a patient continues to take a prescribed drug – tends to be very low among this group. As a result, they frequently experience preventable worsening of disease, making them vulnerable to serious medical risks. For example, according to one study of patients with diabetes and heart disease, mortality rates among those who did not take their medications as prescribe were nearly double the rates of those who did adhere to their regimens, the researchers report.

The problem also increases the likelihood of hospitalisations due to poor health outcomes, resulting in significant excess costs, they add. For instance, patients with diabetes who fail to take their medications as directed have almost twice the total annual health care costs as those who take them correctly, at $16,498 compared to $8,886, and these increased costs affect all purchasers of health care services, including individuals, families and employers. For a typical medium-sized employer with $10 million in claims, the $290 billion national cost of poor adherence may mean an additional $1 million in avoidable health care spending each year, says the Institute, which, in a report issued two years ago on waste and inefficiency in the US health care system, estimated that a full third of the USA’s annual $2.4 billion health care spend could be eliminated without reducing the quality of care.

With 75% of US health care spending going on the treatment of chronic disease, the widespread problem of poor medication adherence presents a serious roadblock to efforts to improve health care efficiency and affordability, say the researchers. However, they add, the current debate on health reform presents an ideal opportunity for policymakers to assess the evidence for improving adherence.

The study identifies the underlying causes of failure to take medication as directed as, fundamentally, confusing regimes, burdensome costs and forgetfulness or other patient behaviours, and, it says, the four most promising solutions to addressing these causes for public and private policymakers to pursue are:

- creating health care teams: while physicians play a key role in improving medication adherence, the issue’s complexities require additional support through care teams - incorporating nurses, pharmacists and other clinicians – which increase the number of checks on adherence as patients move through the system;

- patient engagement and education: counselling by primary care providers or pharmacists to ensure that patients understand the importance of their medicines in improving their condition is critical;

- payment reform: realigning reimbursement incentives would encourage providers to invest in resources such as counselling services that would improve patient outcomes by increasing medication adherence; and

- leveraging health information technologies: secure, reliable and robust information flows via technology such as e-health records, e-prescribing and clinical decision support systems would give providers a full sense of their patients’ current medications, including whether they have filled or refilled a prescription.