Researchers are calling for GPs to review life histories when diagnosing patients after they found that one in 10 people between 18 and 40 being treated for depression in primary care have unrecognised bipolar disorder.
The team, from the Leeds and York partnership NHS trust interviewed and sent questionnaires to young patients aged between 18 and 40 who were taking antidepressants and found that 7.3% of them had unrecognised bipolar disorder.
After adjusting the data, the researchers estimated the nationwide prevalence of unrecognised bipolar disorder in this group was 10% – higher than previous estimates that had put the number recognised in primary care between 0.5% and 4.3%.
A diagnosis of bipolar was found to be more common among younger patients and those who reported more severe episodes of depression.
NICE guidelines state GPs should ‘not use questionnaires in primary care to identify bipolar disorder in adults and the researchers found that using mood disorder questionnaires was not efficient in routine case finding.
However, they suggested the questionnaires might be a helpful supplement to those who are considering a referral to a specialist.
The researchers conclude that GPs should review patients for evidence of unrecognised bipolar disorder – which often presents as depression – before making a diagnosis.
They write: ‘Primary care clinicians should review life histories for evidence of unrecognised bipolar disorder, particularly bipolar II disorder, when seeing patients with depression or anxiety disorder, particularly younger patients and those who are not doing well.’
Professor Roger Jones, editor of the BJGP, said: ‘[The researchers] recommend that general practitioners look carefully at patients with depression and anxiety disorders, particularly younger patients and those who are not doing well with their treatment.
‘By reviewing life histories for evidence of symptoms this could provide people with better treatment and quicker recovery.’
This article was amended at 12pm on 3 February to clarify that one in ten young people treated for depression may have bipolar, and not that one in ten bipolar disorders were unrecognised, as the previous version had stated