Estimated 125,000 deaths.
Every year in the US.

The scale of the problem

Every year in the United States, an estimated 125,000 people die from causes linked to not taking their prescribed medications, according to Li et al., 2024. That is a huge toll, yet it receives a fraction of the attention.

The same paper estimates that medication non-adherence costs the US healthcare system just under $300 billion each year. Separately, Cutler and Everett, NEJM 2010 report that as many as half of all patients do not take their prescribed medications faithfully, and that more than $100 billion a year is spent on avoidable hospitalizations as a result.

Who is most affected

Non-adherence is not evenly distributed. Some groups may face higher risk:

• Chronic disease patients: In developed countries, adherence among patients with chronic conditions such as hypertension, diabetes, heart disease, and asthma averages only about 50%, according to the World Health Organization.
• Elderly adults: Many older adults take several medications. In CDC data, 37% of Americans aged 60 and older used five or more prescription drugs (CDC NCHS Data Brief 42, 2010). Managing complex regimens without support systems makes missed doses and errors more likely.
• Patients without caregiver support: People who live alone or lack family involvement in their health have no one to notice a missed dose, which can make non-adherence harder to catch.
• Patients with cognitive decline: Memory impairment from Alzheimer's, dementia, or mild cognitive impairment makes medication management nearly impossible without external systems.
• Low-income populations: Cost can be a major driver of non-adherence, but forgetting or not understanding regimens also plays a part even when medications are affordable.

Why people don't take their medications

Understanding the causes of non-adherence is essential to addressing it. Common reasons include:

• Forgetting: Patients simply forget, especially with complex regimens or multiple daily doses
• Side effects: Patients stop medications due to side effects, often without telling their doctor
• Cost: Patients skip doses or split pills to stretch a prescription
• Feeling better: Patients stop when symptoms improve, believing they no longer need the medication
• Complexity: Multiple medications, different timing windows, food interactions, and confusing instructions lead to errors and abandonment

The economic cost

The roughly $300 billion figure represents estimated direct US healthcare costs: hospitalizations, ER visits, and additional treatments required when medication non-adherence causes a condition to worsen. It does not include indirect costs such as lost productivity, caregiver burden, or long-term disability.

Costs are only part of the picture. Non-adherence also shapes how often people end up in hospital.

More specifically, published research estimates the following:

• About 1 in 10 US hospitalizations, according to Li et al., 2024
• More than $100 billion a year spent on avoidable hospitalizations, according to Cutler and Everett, NEJM 2010
• As many as half of all patients not taking their prescribed medications faithfully, from the same article

Hypertension: the silent epidemic of non-adherence

Hypertension (high blood pressure) provides one of the clearest examples of how non-adherence can lead to preventable harm. Nearly half of US adults have high blood pressure (48.1%, about 119.9 million people, in 2017 to March 2020 data from the CDC, 2024), and antihypertensive medications are among the most commonly prescribed drugs in the world. Taking them consistently matters.

Uncontrolled hypertension raises the risk of stroke, heart attack, and kidney disease, which can dramatically reduce quality of life.

Diabetes: the adherence gap that causes complications

For people with Type 2 diabetes, taking medication consistently supports blood sugar control, which shapes long-term outcomes. In Stratton et al., BMJ 2000, each 1% reduction in average HbA1c was associated with a 21% lower risk of diabetes-related death. That is why it matters to know whether doses are actually being taken.

Missed doses can leave blood sugar higher than it needs to be, even when a person can afford their prescriptions.

What actually improves adherence

Several approaches are commonly used to help people take their medications consistently:

• Reminders: Text, app, or alarm-based reminders can help people remember doses
• Family involvement: When family members are aware of a regimen and ask about it, a person is not managing alone
• Simplified regimens: Fewer daily doses and clearer instructions make a regimen easier to follow
• Doctor communication: Knowing that a doctor will review adherence can encourage people to take their medications
• Accountability systems: A record of whether each dose was taken makes gaps visible early

The opportunity

Medication non-adherence is not a hopeless problem. The approaches that help are well known, and they do not require major changes to how healthcare is delivered. What they require is a system that patients will actually use daily, that keeps families informed, and that gives physicians actionable data.

That is what Eva is built to be.