Identifying prior signals of bipolar disorder using primary care electronic health records

Abstract

Background: Bipolar disorders (BD) are serious mental illnesses yet evidence suggests that the diagnosis and treatment of BD can be delayed by around 6 years. Aim: To identify signals of undiagnosed BD using routinely collected electronic health records. Design and setting: A nested case-control study conducted using the UK Clinical Practice Research Datalink (CPRD) GOLD dataset, an anonymised electronic primary care patient database linked with hospital records. Cases were adult patients with incident BD diagnoses between 1st January 2010 and 31st July 2017. Method: Cases were matched by age, sex, and registered general practice to 20 controls without recorded BD. Annual episode incidence rates were estimated and odds ratios from conditional logistic regression models were reported for recorded health events prior to index (diagnosis) date. Results: There were 2,366 patients with incident BD diagnoses and 47,138 matched control patients (median age 40 years; 60.5% females). Compared with controls, BD cases had higher incidence of diagnosed depressive, psychotic, anxiety and personality disorders recorded and escalating self-harm, up to 10 years before BD diagnosis. Sleep disturbance, substance misuse and mood swings were more frequent among cases than controls. Cases had more frequent face-to-face consultations and were more likely to miss multiple scheduled appointments and prescribed three different psychotropic medication classes in a given year. Conclusion: Psychiatric diagnoses, psychotropic prescriptions and health service use patterns might be signals of unreported BD. Recognising these signals could prompt further investigation for undiagnosed significant psychopathology, leading to timely referral, assessment and initiation of appropriate treatments.