Bipolar Disorder and Substance Addiction

Bipolar Disorder and Substance Addiction

Bipolar Disorder

Bipolar disorder, also known as manic depression, is a psychiatric condition that affects more than 5.7 million people in the U.S. roughly equal to 2.6% of the national population above 18 years of age. Patients are usually diagnosed in their late teens and more than 50% of all cases are diagnosed before age 25. [NIMH] the disorder is characterized by unusual mood swings that affect the person's ability to carry on his day-to-day activities. These "mood episodes" range from overexcited state called mania and periods of very low emotional state called depression. These mood variations can be short-term or prolonged and seriously affect the patient's ability to perform normal functions. Majority of patients with bipolar disorder also have substance abuse problem. Several studies (Strakowski, et al., 1998, Merikangas, et al., 2007, etc.) have reported a high prevalence of substance use disorder among adults with bipolar disorder. [Willens et.al, 2008] Some studies have also reported a high rate of SUD among patients with early onset disorder. SUD is also highly observed among adolescents with bipolar disorder. A brief overview of BP disorder and some recent studies that focus on its association with substance addiction would provide important insight into the complex spectrum of bipolar disorder and its treatment.

Bipolar Disorder

There are four main types of BP disorder namely Bipolar 1, bipolar 2, Bipolar disorder not otherwise specified (BP NOS) and cyclothymic disorder. BP1 is characterized by manic or mixed episodes that last for more than one week. There is a distinct change from normal behavior and hospital treatment is necessary. BP2 refers to a pattern of depressive episodes alternating with manic episodes without neither of them being fully blown. BP-NOS refers to special cases where the symptoms exhibited do not fit in to either BP1 or BP2 and are of very short duration. Finally cyclothymic disorder refers to a milder form of BP wherein the patient has episodes of hypomania with mild depression over a two-year period. BP disorders usually last a lifetime and appropriate medical treatment is necessary to control the symptoms and to enable the patients lead full productive lives.

BP and Comorbid substance addiction

Frank et.al (2006) was a Pittsburgh study that analyzed 170 patients who were enrolled in the 'Maintenance therapies for Bipolar Disorder' (MTBD). Of these 101 were women and 69 were men. The MTBD program had qualification requirements such as confirmed lifetime diagnosis of bipolar I disorder, age between 18 and 65 and the most recent episode within the last 5 years. Psychiatric evaluation tests such as 'Schedule for Affective Disorders and Schizophrenia' (SADS) and 'Research Diagnostic Criteria' (RDC) was conducted for all the subjects at the time of intake. Also, data pertaining to the history of substance abuse was obtained using NIMH Life Charting Protocols. The researchers also used the 'Hamilton Depression Rating Scale' (HADS) and the 'Bech-Rafaelsen Mania Scale' (BRMS) to assess depression and mixed mania episodes. Statistical chi square tests were used to compare patients with and without substance use. The final data analysis revealed that 59.4% (N=101) had a previous history of substance abuse. Overall the subjects in the 'substance usage (SU) group had more depressive episodes compared to the non-SU group. (Median of 6 as against 3). The study also clearly showed that secondary SU was associated with early onset of BP (mean age=18.9 vs. 21.8, t-test=?2.1, p=.036) as well as more manic episodes (median 3.5 vs. 3, Mann-Whitney test, p=0.047) compared to primary substance usage. It was found that 6.9% of the subjects used substance for the first time just after the first BD mania episode clearly suggesting substance use as a coping mechanism among this group. Also the fact that 49.5% of the subjects had previous history of SA coupled with the fact that 5 out of the ten subjects developed their first mania episode immediately following their substance discontinuance suggests a potential substance usage related sensitization process in the onset of BP disorder. [Frank et.al, 2006)]

Baethge et.al (2005) examined substance use disorders in patients with first episode BP 1 disorder using 'Structured Clinical Interview for DSM-IV Axis I Disorders' (SCID). The study included a total of 172 patients who were admitted in the McLean hospitals between 1989 and 1996 for clinically diagnosed first lifetime manic/mixed BP 1 episodes. All the 172 subjects underwent follow-up assessment at 6,12 and 24 months respectively. Results from the study indicate that 37 (33.0%) were substance addicts at entry and this increased to 38.8% at the end of the study period. Statistical analysis further revealed that cannabis dependent subjects had more prolonged manic episodes (mean=26.8%, SD=34.0%, versus mean=11.5%, SD=19.1%; ratio=2.3:1), whereas alcohol dependant subjects had increased episodes of depression (mean=11.9%, SD=22.9%, in mania vs. mean=21.9%, SD=29.5%, in depression; ratio=1:1.8). Also morbidity was higher among polysubstance abusers. [Baethge et.al, 2005]

A more recent study by Wilens et.al (2009) analyzed 105 bipolar adolescent probands and 98 non-mood disordered control subjects. The first-degree relatives of the subjects were also assessed. This study by the Massachusetts General Hospital used DSM-IV-based structured interviews. The researchers interviewed primary caregivers, adolescent subjects and their siblings. Data pertaining to substance abuse was gathered using the DSM-IV Kiddie Schedule for Affective Disorders (KSADS) diagnostic criteria. The results indicated that subjects with BP disorder had an overall higher rate of substance use disorder (controls 4% and BPD 34%). Alcohol abuse (controls 3%, BPD 23%) and drug abuse (controls 1%, BPD 22%) were higher among the BP subjects. Statistical analysis also revealed that 14% of BP subjects had both alcohol and drug use disorder compared to none in the control group. This study clearly showed that there was a clear association between BP disorder and different types of substance use disorders. [Wilens et.al (2009)]