Interrogation of coded healthcare data to facilitate identification of patients with a rare neurotransmitter disorder; Aromatic L-Amino acid decarboxylase deficiency

Abstract

Background and aims

Aromatic L-Amino Acid Decarboxylase deficiency (AADCd) is a rare, phenotypically heterogenous neurotransmitter disorder, posing challenges for diagnosis. We aimed to assess the efficacy and acceptability of interrogating routine hospital data to identify possible AADCd patients.

Methods

Design: Mixed methods feasibility study.

Setting: UK Secondary and tertiary care hospitals.

Procedure: A Structured Query Language (SQL) query was applied to hospital datasets to produce filtered lists of patients, ranked according to the presence of AADCd-consistent diagnostic and procedural codes. Findings were collected using a study proforma. No patient data was reported to the research team.

Results

Seven sites (five tertiary) participated. Data collection spanned June 01, 2022 to October 31, 2023. 340 medical records were reviewed, of which 76 patients had previously been investigated for a possible neurotransmitter disorder, 4 were currently being investigated, 31 were suitable for investigation, with 9 subsequently approached for further testing. No patients were identified as having AADCd. Thematic feedback included accuracy and technical, application challenges. Three sites reported this method could help identify AADCd patients.

Conclusions

Medical record interrogation to identify potential AADCd patients is feasible. Challenges including operational capacity, technical issues and uncertainty regarding efficacy remain.