One striking finding was a decadelong lag between the onset of symptoms reaching thresholds for diagnosis and the onset of first treatment.2 This long delay could have adverse consequences for illness outcome and represents a major public health target. Age of onset appeared to have both genetic/familial and environmental determinants.3 Subjects with a history of both extreme early life adversities (i.e., physical or sexual abuse) and a positive family history of mood disorder had the earliest onset of bipolar illness. Those who had neither of these factors had late-onset illness.
Suicide attempts
Prior to network entry, 25 to 50% of our study population had made a serious suicide attempt (defined as requiring medical attention and/or hospitalization), pointing to bipolar disorder’s potential lethality.
History of abuse A history of physical or sexual abuse in childhood or adolescence was a prominent risk factor for attempted suicide.4 With either type of abuse there was an approximate 15% increase in incidence of suicide attempts over the baseline rate of about 25%. More than 55% of patients with a history of both physical and sexual abuse had made a serious suicide attempt. The frequency of physical and sexual abuse was also positively related to increased incidence of suicide attempts. Taken together, these data suggest a “stressor dose-response” relationship between adverse childhood or adolescent experiences and an increased incidence of suicide attempts.
Table 2
FACTORS THAT APPEAR TO INCREASE SUICIDE RISK IN BIPOLAR DISORDER*
| Course-of-illness characteristics |
| Early onset |
| More time ill |
| More time depressed |
| More-severe depression |
| Social and medical support |
| Loss of significant other |
| Lack of a confidant |
| Single motherhood |
| Decreased access to health care |
| Lack of medical insurance |
| Demographics |
| Less education |
| Lower income |
| Being single |
| Comorbidities |
| Axis I |
| Eating disorders |
| Anxiety disorders |
| Axis II |
| Cluster A, B, C |
| Medical |
| Traumatic life events |
| Sexual abuse |
| Physical abuse |
| Genetics |
| Family history of suicide and drug abuse |
| * Identified in the SFBN cohort |
Comorbidities Other factors that appear to be associated with bipolar disorder and increased risk of attempted suicide include anxiety and eating disorders, early onset of symptoms, at least four previous hospitalizations for depression, and medical comorbidity (Table 2). Limited access to psychiatric and medical services and inadequate health insurance also were correlated with having made a serious suicide attempt. Thus, lack of medical care might exacerbate demoralization and increase the risk of suicide.
Family history of suicide or serious suicide attempts and drug abuse were associated with an increase in suicide attempts, but family history of unipolar or bipolar illness were not. These data are consistent with other studies suggesting that vulnerability to suicide may have a separate genetic component from that of mood disorders per se.
Severity of illness Increased severity of bipolar illness also was associated with prior psychosocial stressors3 and serious suicide attempts. We confirmed self-reported history, using daily mood charting, the clinician-rated Inventory of Depressive Symptomatology (IDS-C), and the Young Mania Rating Scale (YMRS) to rate increase in percentage of time ill, percentage of time depressed, and severity of depression.
Clinical implications We are uncertain how directly these data regarding suicide attempts relate to completed suicide. However, patients with bipolar disorder are among those at highest risk for completed suicide, and a prior serious attempt is often a precursor to completed suicide.5,6
Factors that appear particularly related to increased risk of suicide in patients with bipolar disorder are family history of suicide, history of early psychosocial stressors, comorbid personality disorders, substance abuse, and a relatively severe course of bipolar illness. Patients with these risk factors need support for two types of psychosocial stressors:
- poor access to health care
- stressors related to concurrent events (e.g., occurring with new affective episodes).
It may also be important for clinicians to consider the prophylactic use of lithium because of its demonstrated ability to reduce mortality in bipolar illness.7 Additionally, we need data on the efficacy of new drugs in preventing affective episodes and reducing suicidal ideation and acts.
Common comorbidities
We found considerable axis I lifetime comorbidities in the SFBN cohort (Table 3), including a 42% incidence of anxiety disorder and a similarly high rate of substance abuse. In addition to bipolar disorder, patients averaged approximately two lifetime comorbid diagnoses:
- 35% had none
- 65% had one or more
- 42% had two or more
- 24% had three or more.
Table 3
PSYCHIATRIC COMORBIDITY IN BIPOLAR OUTPATIENTS (%)*.
| Any substance abuse disorder | 42% |
| Alcohol | 33 |
| Marijuana | 16 |
| Stimulant | 9 |
| Sedative | 8 |
| Opiate | 7 |
| Hallucinogens | 6 |
| Any anxiety disorder | 42% |
| Panic disorder | 20 |
| Social phobia | 16 |
| Simple phobia | 10 |
| OCD | 9 |
| PTSD | 7 |
| GAD | 3 |
| Other | 3 |
| Any eating disorder | 11% |
| Bulimia nervosa | 8 |
| Anorexia nervosa | 4 |
| * Lifetime comorbid axis I disorders based on Structured Clinical Interview for DSM-IV (SCID) interviews with 288 SFBN patients. | |
Men with bipolar disorder had a higher absolute prevalence of alcoholism, but the relative risk compared with the general population was much higher in women (odds ratio 7.35) compared with men (odds ratio 2.77). In women, alcohol use and abuse were related to history of social phobia, greater number of depressive episodes prior to network entry, and history of abusing more than one substance. In men, alcohol comorbidity was related to history of alcohol abuse in first-degree relatives and history of early physical abuse.