Major disparities in patient‐reported adherence compared to objective assessment of adherence using mass spectrometry: A prospective study in a tertiary‐referral hypertension clinic

摘要

Aim Many challenges exist in determining true rates of adherence to antihypertensive medications among individuals in a clinic setting. For the first time, we aimed to compare patient‐reported antihypertensive adherence with objective evidence using mass spectrometry spot urinalysis in a tertiary referral clinic setting. Methods A prospective observational single‐centre cohort study was performed in a tertiary referral hypertension clinic, encompassing antihypertensive initiation and persistence. Patients were referred with apparent treatment‐resistant hypertension or for suspected secondary causes. Participants completed a self‐reported assessment of antihypertensive adherence and provided a spot urine sample. The presence of antihypertensive medications and/or their respective metabolites was evaluated using high‐performance liquid chromatography tandem mass spectrometry. Patients were determined to be adherent if they demonstrated both self‐reported adherence and objective mass spectrometry evidence. Results Of all 105 eligible participants initially recruited, 73 (69.5) met the eligibility criteria. Only 27.4 (95 confidence interval 0.2‐0.4) of participants demonstrated true adherence to their self‐reported antihypertensives, despite 75.3 (0.6‐0.8) reporting adherence. Greatest medication adherence was achieved with angiotensin II receptor blockers (61), with calcium‐channel blockers and mineralocorticoid antagonists demonstrating least adherence (38). Conclusion In patients attending a tertiary hypertension clinic, the combined use of spot urine mass spectrometry and self‐reporting identifies higher rates of nonadherence when compared to either modality alone. Both techniques should be combined for more accurate detection of medication adherence.