In a new study, researchers from the University of Leeds suggested that around 10 percent of UK primary care patients prescribed antidepressants for either depression or anxiety may actually have bipolar disorder (BD).
This is significant given the fact that BD affects nearly 2 percent of the world's population and is the sixth leading cause of disability worldwide, according to the National Health Service (NHS).
BD is a brain disorder that causes dramatic shifts in mood, energy and the ability to think clearly. Patients often have extreme high and low moods, known as mania and depression, which are different from the normal ups and downs of everyday life. If left untreated, these symptoms usually get worse.
BD is often difficult to diagnose because many patients don’t see their mania as a significant symptom and neglect to mention it to their doctors.
Misdiagnosis can lead to inappropriate treatment. When an antidepressant is prescribed without a mood stabilizer, the mood of a patient with BD can become even further destabilized.
To assess how many UK patients were misdiagnosed, researchers used NHS data to look at 236 patients from 21 practices in England who were prescribed antidepressants. All patients were between the ages of 16 and 40, as 95 percent of BD cases begin before age 40.
All patients were given a mood disorder questionnaire (MDQ) and interviewed.
Around 10 percent of the patients met the criteria for BD. Undiagnosed BD was more common in younger patients who reported more severe episodes of depression.
"Bipolar disorder is a serious problem, with high levels of disability and the risk of suicide," said study co-author Tom Hughes, MD, in a press release."When it is present in depressed patients it can easily be overlooked. We hope this study will be of some help to them and to their patients in helping the better recognition of this important and disabling condition."
Dr. Hughes is a consultant psychiatrist at the NHS Foundation Trust and the University of Leeds.
Dr. Hughes and team urge health care professionals to review the life histories of patients with anxiety or depression, especially younger patients who are not responding well to treatment, for evidence of BD.
This study will be published in the February issue of the British Journal of General Practice.
The National Institute for Health Research funded this research. No conflicts of interest were disclosed.