Identifying and addressing cognitive problems is crucial for achieving important patient outcomes in major depressive disorder (MDD), including improvements in quality of life, work, and prognosis. The best predictor of poor functioning is presence of cognitive impairment when patient is considered to be in remission.
The best predictor of poor functioning is presence of cognitive impairment when patient is considered to be in remission
Both subjective and objective measures can be used to assess cognition. Subjective measures are easier to implement in a clinic setting, with questions on daily life cognition and mood symptoms. Objective measures are more time-consuming, traditionally require neuropsychological assessment, and impractical for busy clinicians.
Free screening tools are quick and easy to perform
To address this, the Cognition Task Force of the International Society for Bipolar Disorders (ISBD) has recently developed helpful and consensus-based recommendations for clinicians on cognitive assessment and management, which can also be applied to other mood disorders. Their website provides links to both subjective (COBRA - cognitive complaints in bipolar disorder rating assessment) and objective (SCIP - screen for cognitive impairment in psychiatry) assessment tools1. These free, validated, multi-lingual tools are quick (≤ 15 minutes) and easy for clinicians to perform. Thresholds of >14 for COBRA and <70 for SCIP have good specificity for cognitive symptoms. Ideally, testing should be done when the patient is in remission, as clinical status at the time will affect results, and educational level/IQ should also be taken into account.
If cognitive symptoms are detected, then the next step, Professor Vieta suggested, is to determine if the cause is primary or secondary2. Underlying secondary causes are important to identify, as many can be treated effectively. They include mood, comorbidities, lifestyle issues and medication.
Secondary causes are important to identify and treat cognitive symptoms
Subthreshold depressive symptoms can cause issues with cognition, even if patients think they have recovered, hence importance of targeting complete remission. Comorbidities may not be obvious, and the possibility of alcohol or substance use or illicit drug use, and anxiety disorders should be considered, as well as medical non-psychiatric conditions including hypothyroidism, metabolic syndrome, diabetes and hypertension. Medication may help some symptoms, but can also worsen cognitive symptoms, and dose and type of agent should be reviewed, although switching drugs may not be advisable if patient is stable. Polypharmacy is common, and a correlation has been found between the number of medications and cognitive symptoms.3
It is important to consider that patients may have a co-existing organic brain illness or dementia, and these patients should be referred for full diagnostic assessment. Other causes of primary cognitive impairment include obstetric complications, neurodevelopment abnormalities, or allostatic load of previous manic or psychotic episodes.
Several promising agents are being investigated
If no treatable secondary cause is found, Professor Vieta advised at least yearly screening to track cognition over time, and recommended using the new ISBD patient information booklet1, to give patients information and advice on managing their cognitive symptoms.
There was lively audience participation during the brainstorming time, with discussion of areas including improving cognitive reserve, associated risk of dementia in mood disorders, and possible therapeutic interventions.