Initial non-adherence to antihypertensive medications in the United States: a systematic literature review.

An important component of hypertension management is the initiation and continuation of antihypertensive medications. Non-adherence during the long-term use of antihypertensive medications is well studied. However, there is a paucity of research about the frequency and clinical consequences of failing to take the first dose of an antihypertensive, a treatment challenge known as initial medication non-adherence (IMN). This systematic literature review summarizes the published evidence from 2010 to 2019 on the prevalence, associated factors, consequences, and solutions for IMN to antihypertensive medications in the United States. Of the fifteen studies identified, nine studies reported the prevalence of IMN, two studies examined patient-reported reasons for IMN, and four studies evaluated interventions aimed to lower IMN. It is estimated that 5-34% of patients do not obtain their new antihypertensive medications. Factors and reasons cited include patient demographics, patient beliefs or perceptions about medications, cost or financial barriers, and clinical characteristics, such as a new hypertension diagnosis or higher co-morbid disease burden. The clinical, economic, and patient-reported outcomes of IMN are not well researched. In addition, interventions to address IMN have yielded inconsistent results. Significant opportunities exist for further research into this dimension of patient behavior to better understand and address IMN to new antihypertensive medications.