A Novel Algorithm for Identifying Generalized Pustular Psoriasis Flares Using Natural Language Processing and Outpatient Electronic Health Records (Preprint)

BACKGROUND Generalized pustular psoriasis (GPP) is a systemic, neutrophilic, inflammatory disease characterized by chronic symptoms and periods of flaring, which can be potentially life-threatening. The rarity of GPP and inconsistent documentation complicate real-world identification of GPP flares. OBJECTIVE We developed an algorithm to identify outpatient encounters indicative of GPP flares using structured data and unstructured clinical notes from electronic health records (EHRs). METHODS De-identified patient-level EHR data (2017–2024) from six specialty dermatology networks in the USA were accessed. Eligible outpatient encounters had (1) an International Classification of Diseases, 10th Revision, Clinical Modification diagnosis code for GPP, (2) a dermatologist-defined diagnosis status of “inadequately controlled” or “worsening” disease (gold standard indicator of flare), and (3) available clinical notes. Natural language processing (NLP) of clinical notes identified the most common terms (eg, clinical manifestations, treatment) by flare status. RESULTS Multivariable logistic regression models and leave pair-out cross-validation selected models yielding the highest area under the receiver-operating characteristic plot (AUROC) (discriminative ability for flares) from 1,354 encounters (679 patients: 81% female, 84% Caucasian, mean age 58 years). The final model combined NLP terms and EHR variables and yielded a higher discriminative ability (AUROC=0.72; sensitivity=0.68; specificity=0.66) than either NLP terms or EHR data alone. CONCLUSIONS Although not fully discriminative, the model could be used in future to identify GPP flares from EHR data. CLINICALTRIAL N/A