Assessing appropriateness of drug therapy in older persons: Development and application of a medication assessment tool for long-term management of atrial fibrillation

BACKGROUND: Atrial fibrillation (AF) is highly prevalent in older persons and is associated with considerable morbidity and mortality. Assessing appropriateness of drug therapy in AF may be facilitated by application of medication assessment tools (MATs). OBJECTIVE: To develop, psychometrically evaluate and apply an innovative MAT for the long-term management of AF with particular relevance to older persons. METHODS: Key recommendations from clinical practice guidelines for the long-term management of AF were selected and review criteria defining appropriate drug therapy were constructed as a ‘qualifying statement’ followed by a ‘standard’. The developed MAT was given the designation MAT-AF. An application guide was compiled where justifications for non-adherence were specified. Content validity was tested by an expert group using a three-round Delphi process. Inter- and intra-observer reliability testing was conducted with agreement expressed by Cohen’s kappa and application time measured to assess feasibility. MAT-AF was applied to 150 patients with a diagnosis of AF admitted to a rehabilitation hospital. RESULTS: MAT-AF consists of 15 criteria sectioned into antithrombotic, rate control and rhythm control therapy. Content validity was demonstrated for all criteria. Reliability was confirmed with kappa values of 0.84 and 0.91 for inter- and intra-observer agreements. Mean application time for the two observers was 3.9 and 2.4 minutes, which decreased significantly in the second application conducted after a four-week interval (p<0.001). Overall adherence to applicable criteria was 59.8%. Non-adherence was evident for prescription of anticoagulation in patients with a CHA(2)DS(2)VASc score ≥1 (29.5%). Monitoring of laboratory parameters for digoxin was suboptimal. Ophthalmic and pulmonary monitoring and patient counselling regarding amiodarone therapy could not be assessed since relevant records were not readily available. CONCLUSION: MAT-AF application highlighted key aspects which need to be addressed to improve patient care.