Active Choice Nudge to Increase Screening for Primary Aldosteronism in At-Risk Patients

Background: Primary aldosteronism (PA) is the most common cause of secondary hypertension, yet screening remains startlingly infrequent. We describe: 1) PA screening practices in a large, diverse health system, 2) the development of a computable phenotype for PA screening, and 3) the design and pilot deployment of an electronic health record (EHR)-based active choice nudge to recommend PA screening.

Study design: A multidisciplinary team developed a multi-pronged intervention to improve PA screening informed by guidelines, expertise, and multivariable analyses of factors associated with screening. The intervention included EHR-based tools to automatically identify screen-eligible patients, an active choice nudge recommending screening for these patients, and screening result interpretation. The intervention was piloted across two primary care practices for seven months. Screening frequencies were compared to clinics not receiving the intervention.

Results: The baseline frequency of screening of eligible patients within one year was 1.4%. Higher mean systolic blood pressure (OR=1.4; p<0.001), more antihypertensive medications (OR=1.3; p=0.002), lower minimum serum potassium (OR=2.0; p=0.001), specialist care (OR=3.0; p<0.001), and Black race (OR=1.5; p=0.001) were associated with a higher likelihood of screening. The refined computable phenotype identified a subcohort with a higher frequency of positive screening (8.6% versus 4.1%; p=0.03). In a pilot study of an active choice nudge, a greater proportion of eligible patients were screened in the intervention clinics (16.4%) than in the non-intervention clinics (1.8%; p<0.001).

Conclusion: PA screening rates are low. This pilot study suggests an EHR-based nudge leveraging a precise computable phenotype can dramatically increase appropriate PA screening.