Patients who frequently miss doses of blood pressure medication may lose most of its protective benefits against heart attacks and strokes, according to an analysis of more than 91,000 people presented at ESC Congress 2026.
An estimated 1.4 billion adults worldwide aged 30 to 79 have hypertension, a major contributor to cardiovascular illness and death. Although blood pressure medications are proven to reduce cardiovascular risk, approximately half of patients do not take their prescriptions as directed.
Researchers from the University of Oxford analysed individual patient data from nine clinical trials comparing blood pressure treatment with placebo or less intensive regimens. Participants were divided into two groups: those taking at least 80% of their prescribed medication (higher adherence) and those taking less than 80% (lower adherence).
The findings revealed a striking contrast in outcomes. Among patients with higher adherence, systolic blood pressure was 5.2 mmHg lower in the treatment group compared with controls. For those with lower adherence, the difference was just 3.0 mmHg.
More significantly, patients who consistently followed their treatment plans experienced an 11% reduction in major cardiovascular events, including strokes, heart attacks and heart failure requiring hospitalisation. Those with lower adherence showed no statistically significant reduction in these events.
Even in the structured setting of clinical trials, adherence declined over time. Whilst 88% of participants met the higher adherence threshold during the first year, only 79% did so by the fifth year.
The researchers recommend routine adherence assessments, better patient education and practical strategies such as simplifying medication schedules, combining treatments into single pills and prescribing longer-acting drugs to limit the consequences of occasional missed doses.
Source: Yang Q et al. Impact of adherence on antihypertensive treatment benefits. Presented at ESC Congress 2026.