Misidentification of mental health symptoms in presence of organic diseases and delirium during psychiatric liaison consulting.

OBJECTIVE: To identify predictors of misidentification of organic mental disorders and delirium in patients undergoing psychiatric liaison consultation.

METHODS: Data were collected at Santa Casa de São Paulo between July of 2009 and March of 2013. We included in our analysis all inpatients for whom the requesting service judged that a psychiatric consultation was required for a possible mental health condition. Outcomes of interest were the instances of misidentification where a condition was initially deemed to be of a psychiatric nature, whereas the final diagnosis by the liaison psychiatric team was of an organic disease or delirium. Our predictors were the clinical specialty of the requesting service, requester and patient characteristics. A series of generalised linear models were used to evaluate misidentification risks.

RESULTS: A total of 947 subjects met our inclusion criteria, 14.6% having a final liaison diagnosis of organic mental disorder and 8.1% of delirium. Older patients were significantly associated with increased risk of misidentification for both organic conditions (OR 3.01 - 95% CI 2.01, 4.5) and delirium (OR 3.92 - 2.4, 6.39).

CONCLUSIONS: Educational interventions in general hospitals focused on preventing psychiatric misdiagnosis should target in-hospital services where patients tend to be older.