Risk Factors for the Onset of Bipolar Disorder and Factors Influencing Recognition: Results from NEMESIS

Abstract

Aims:

Risk factors for the onset of bipolar disorder and factors influencing recognition were examined in a general population sample.

Method:

In the Netherlands Mental Health Survey and Incidence Study (NEMESIS) symptoms of depression, mania, psychosis and substance use were assessed among 7076 respondents with the Composite International Diagnostic Interview at baseline, after one and after three years. In a reappraisal study among 40 respondents with bipolar disorder confirmed by the Structured Clinical Interview for DSM-IV (SCID) data on illness and treatment history were collected.

Results:

Predictive values of subclinical depression and (hypo)mania for bipolar disorder ranged from 14.3% to 50%. Cannabis use at baseline increased the risk for manic symptoms during follow-up (OR 2.70, 95%CI:1.54-4.75) (Henquet et al., 2006). Comorbid subclinical psychosis in respondents with subclinical mania had predictive value for future diagnosis of bipolar disorder (positive predictive value of 3% versus 10% respectively) (Kaymaz et al., 2007). The majority of the respondents with a SCID diagnosis bipolar disorder consulted a health professional, only 12.5% received a diagnosis of bipolar disorder and agreed with the diagnosis. Only these respondents used a moodstabilizer and had contact with a psychiatrist. Type of bipolar disorder, number of mood episodes and age of onset did not influence recognition.

Conclusion:

Subclinical depression and (hypo)mania, and comorbity of subclinical psychosis and mania are predictive for future diagnosis of bipolar disorder. Cannabis use affects the expression of manic symptoms. Self-recognition of bipolar disorder is an important factor in treatment seeking and receiving adequate treatment.