Stability of admission diagnoses; data from a specialized in-patient treatment facility for dual diagnosis.

We investigated the stability of diagnoses during admission over an 11-year period in patients admitted to a highly specialized integrated dual diagnosis treatment facility in Denmark using diagnosis coded in patient charts.
Admission and discharge diagnoses from patient files were examined for stability of primary diagnosis and association with year of admission, age, sex, and duration of admission, in 1570 patients from 2007 to 2017.
A vast proportion (69.6%) of the patients retained their diagnosis during a 3-month admission. Stability was highest for schizophrenia spectrum diagnoses and lowest for unspecified diagnosis. Type of primary diagnosis, age, and length of admission was associated with lower likelihood of a stable primary diagnosis.
Long-term admission for psychiatric patients with substance use disorder (SUD) was significantly associated with stability of diagnosis. The finding calls for longer observation of dual diagnosis patients to ensure that relevant diagnosis is given, and consequently that the appropriate clinical treatment such as psychopharmacological as well as non-pharmacological intervention can be applied.