Bipolar disorder a common feature in urban primary care practice

According to a study in the February 23 issue of JAMA. Nearly 10 percent of patients screened at a general medicine clinic in an urban area were found to have a history of bipolar disorder.

Bipolar disorder consists of episodes of manic and depressive symptoms, according to background information in the article. One or more episodes of manic or hypomanic symptoms such as elevated or irritable mood, racing thoughts, a decreased need for sleep, talkativeness, and excessive involvement in risk-taking activities are necessary to diagnose a bipolar disorder. Hypomania and mania share the same symptoms, but hypomania is less severe. Patients with bipolar disorders are more likely to seek treatment during an episode of depression than hypomania or mania.

Determining whether depression is part of a bipolar disorder is essential for appropriate pharmacological management, because treating patients with bipolar disorder with an antidepressant alone (that is, without a mood-stabilizing drug such as lithium) risks triggering mania, hypomania and rapid cycling between depression and mania.

In a study conducted by Amar K Das, M.D., Ph.D., of the New York State Psychiatric Institute and Columbia University, New York, and colleagues, to estimate the lifetime prevalence of bipolar disorder for patients in an urban general medicine clinic and to compare demographic, clinical, and treatment characteristics of patients who screen positive for a history of bipolar disorder with those who do not.

The study of 1,157 patients between 18 and 70 years of age who were seeking primary care at an urban general medicine clinic serving a low-income population. The study was conducted between December 2001 and January 2003.A diagnosis of bipolar disorder was determined by various questionnaires and surveys and reviewing data on past mental health treatments and records.

The researchers found that the prevalence of positive screening results for lifetime bipolar disorder was 9.8 percent and did not differ significantly by age, sex, or race/ethnicity. Eighty-one patients (72.3 percent) who screened positive for bipolar disorder sought professional help for their symptoms, but only 9 (8.4 percent) reported receiving a diagnosis of bipolar disorder. Seventy-five patients (68.2 percent) who screened positive for bipolar disorder had a current major depressive episode or an anxiety or substance use disorder. Of 112 patients, only 7 (6.5 percent) reported taking a mood-stabilizing agent in the past month. Primary care physicians recorded evidence of current depression in 47 patients (49 percent) who screened positive for bipolar disorder, but did not record a bipolar disorder diagnosis either in administrat ive billing or the medical record of any of these patients. Patients who screened positive for bipolar disorder reported worse health-related quality of life as well as increased social and family life impairment compared with those who screened negative.

"The high estimated prevalence in this clinical setting (9.8 percent) may be related to the low socioeconomic status of the population. In a national study, lifetime prevalence of bipolar disorder was highest (5.7 percent) among participants with the lowest annual household income (less than $20,000/year). In our clinical sample, nearly nine in ten participants reported a household income below $18,000 per year, and the rate of screening positive for lifetime bipolar disorder was inversely associated with household income. These findings are consistent with community-based studies that have shown that economically disadvantaged individuals have higher rates of mental disorders than their more affluent counterparts," the authors write.

"In an urban general medicine practice, screening positive for bipolar disorder is relatively common but frequently under recognized and is associated with poor health-related quality of life, impairment in social activities and family life, and current suicidal ideation. A significant proportion of primary care participants who screened positive for bipolar disorder present with major depression or an anxiety or substance use disorder. These participants are at risk for adverse events if prescribed antidepressant monotherapy," the authors write. "To improve the recognition and reduce the morbidity of bipolar disorders in primary care, further efforts are needed by primary care physicians to screen selectively for past hypomania or mania among participants with known depression, anxiety, or substance use conditions."