The research, published by the British Journal of Psychiatry, examined the rates of medical illness in 1,720 adult patients with bipolar disorder and compared them to 1,340 people who did not have the condition. They also looked at features of bipolar disorder that were most associated with co-occurring medical illnesses.
The study found that a high burden of medical illness was associated with a history of anxiety disorder, ‘rapid cycling’ mood episodes (where a person with the disorder experiences four or more episodes of mania or depression in one year), and suicide attempts during the bipolar illness.
The most common co-occurring medical illnesses were migraine, asthma, and elevated blood lipids (which are associated with high cholesterol). Each of these conditions was reported in one fifth of bipolar patients. Other illnesses found at increased rates in bipolar patients included hypertension, thyroid disease and osteoarthritis.
Researchers concluded that possible links between the mental health disorder and a range of physical illnesses should be taken into account by healthcare services in order to improve outcomes for patients with bipolar disorder.
Researcher Professor Nick Craddock said: “This study confirms what we see in the clinic: mental illness and physical illness commonly affect the same person and must both be taken into account when providing help and treatment.
“Increased rates of physical illness in people with bipolar disorder contribute to the poor health and early death that is experienced by too many patients.
“The research indicates that it is very likely there are shared biological mechanisms between bipolar disorder and several physical illnesses that explain why they often occur together in the same person.”
Commenting on the findings, NCMH Director Professor Ian Jones said “This research reaffirms the need for healthcare services to look at the bigger picture when treating patients with bipolar.”
“It shows how research can help improve our understanding of bipolar disorder, which in turn will enable us to improve diagnosis and treatment in the future. This emphasises the need for studies, such as NCMH, that enlist the help of large numbers of people with mental health problems”.