Brief Oral Papers
Systems-Based Practice and Administrative Psychiatry
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Margaret R. Puelle, MD
Senior Instructor
University of Rochester
Rochester, New York
Daniel Maeng, PhD
Assistant Professor
University of Rochester Medical Center
Rochester, New York
Francisco Tausk, MD
Professor of Dermatology, Allergy, Immunology and Rheumatology
University of Rochester
Rochester, New York
Hochang Lee, MD, FACLP (he/him/his)
John Romano Professor and Chair
University of Rochester Medical Center
Rochester, New York
Background/Significance: Patients with delusional parasitosis (DP) suffer from the false, fixed belief that they are infested by bugs, worms, or inanimate objects and are intermittently encountered in dermatology and other specialty settings. Treatment with antipsychotics is often effective, but DP patients are reluctant to seek psychiatric care and seen by non-psychiatrists who are uncomfortable prescribing antipsychotics 1. Due to difficulty in establishing a therapeutic relationship, DP patients seek out multiple physicians, including repeat use of the emergency departments (ED), in pursuit of diagnosis and treatment 2. Most prior studies have been limited to single-center, retrospective case series, and the pattern and magnitude of overutilization of healthcare by these patients has not been well characterized. Conclusion/Implications: Early identification and treatment of delusional parasitosis through integrative behavioral health care in non-psychiatric settings has the potential to improve outcomes and decrease ineffective health care overutilization. 1. Reich A, et al. Delusions of Parasitosis: An Update. Dermatol Ther (Heidelb). 2019;9(4):631. 2. Foster AA, et al. Delusional infestation: Clinical presentation in 147 patients seen at Mayo Clinic. J Am Acad Dermatol. 2012;67(4):673.e1-673.e10.
Methods: Using a multi-payer claims database of 12 Western New York Counties, we identified a group of DP patients (n=18; Study Group) via two methods: 1) a psychodermatology clinic that utilizes ICD 10 codes L98.8 and B88.9 only for DP 2) patients for whom any dermatologist billed using an ICD 10 code for a psychotic disorder (F2*). For comparison, we identified general dermatology patients with other psychotic disorders (n=634; Comparison Group 1) and mood disorders (n=34,729; Comparison Group 2). We compared the annual rates of ED visits, inpatient admissions, and outpatient visits (primary care, specialists, and mental health providers) among the three groups.
Results: The DP patients had similar rates of ED visits as dermatology patients with other psychotic disorders (2.64 vs. 2.52 per year) however the DP group had twice as many inpatient admissions of any type (0.96 vs. 0.48 per year) and 44% more specialist visits (12.6 vs. 8.76 per year). Compared to dermatology patients with mood disorders, the DP group were admitted 8 times as often (0.96 vs. 0.12 admissions per year) and saw specialists twice as often (12.6 vs. 6.84 visits per year). They had a higher rate of primary care visits (9.36 per year) than either comparison group (8.28 and 5.4 visits per year for patientsts with psychosis or mood disorders, respectively). In contrast, DP patients saw mental health providers for 0.84 visits per year, a fraction of the rates for patients with psychotic or mood disorders (4.8 and 2.52 visits per year).
Discussion: As far as we know this is the first study examining the pattern and magnitude of healthcare utilization among DP patients in comparison to general dermatology patients with psychiatric comorbidities. Our analysis confirmed that DP patients are frequent utilizers of the ED, specialty services, and primary care, while their use of mental health services is minimal. Since most providers are ill-trained to treat psychotic symptoms, DP patients are unlikely to receive effective treatment.
