Dr. Grossi's Blog

Bipolar Spectrum Disorder

Dr. Philip Grossi
Thursday, 27 January 2011

I thought I would devote this blog to bipolar spectrum disorder because its explanation and description occupies so much time in the office due to its commonality, complexity and extraordinary variety of presentation and life course.  It is in a sense a great masquerader because it can appear in the guise of a panic or anxiety disorder, a major depressive disorder or even as an acute paranoid psychosis or post traumatic stress disorder and/or coexists with other problems. This is then being posted mostly for patients to refer to and to reduce the time needed for my oral presentations. 

Bipolar I (BPI or the older term Manic Depressive) has a lifetime prevalence of 1.0%, Bipolar II (BPII) has a lifetime prevalence of 1.1%, Bipolar NOS (BPNOS) has a lifetime prevalence of 2.4%.  C. Moreno and colleagues and J.C. Blader and colleagues have found increased BP diagnosis in adult and pediatric populations.  Hirschfeld, Olfson, and McIntyre and their respective colleagueal groups have studied primary care groups and found that those patients manifesting and being treated for significant depressive symptomatology have an approximately 30% chance of falling in the bipolar spectrum.

What would account for the increased diagnosis of bipolar disorder?  Several explanations have been advanced.  A much wider conceptualization of bipolar disorder starting in earnest in the mid 1980s, overdiagnosis especially in young populations (possibly influenced by drug company marketing), much increased attention in the lay press, and finally some genetic explanation involving anticipation (younger age of onset) as well as assortative mating.

Prompt diagnosis of bipolar spectrum disorder is important because it reduces the risk of suicide, chronicity, and risk of relapse, to say nothing about the increased quality of life that is made possible.  Numerous studies have found that the average length of time between symptomatic presentation and diagnosis is between eight  to ten years.  Three years ago Patty Duke, the child movie star, spoke to a group of psychiatrists about her own experience.  She developed symptoms in the late teen years but was not diagnosed until she was 35 years old.  During those intervening sixteen or seventeen years she spent months at a time in bed arising only to go to the toilet and thinking repeatedly about suicide.   This delay in diagnosis is the rule rather than the exception.

illustration to bipolar spectrum disorder blog

I do not plan to review the diagnostic criteria for bipolar disorders because they are readily available at many sites including several links which can be accessed from the home page of this site.  However, I will review some of the clinical findings that help to differentiate BP spectrum from unipolar depression.  Any depressed person should be appraised for  bursts of increased energy and decreased need for sleep (hypomania).  BP spectrum disorders have an earlier age of onset, usually before 25 years of age.  An individual who meets criteria for a major depressive disorder who is not yet 20 years old has a much higher likelihood of developing into a bipolar patient than individuals who develop depression later in life. Cyclicality is the watchword for BP spectrum since mood swings is the major pathology rather than depression. This results in briefer periods that are symptom-free. The depression in BP spectrum tend to have some distinguishing characteristics, including a more abrupt onset that those with major depression.  BP spectrum patients tend to experience mood destabilization with sleep deprivation and transmeridian travel (this is common in Silicon Valley due to the amount of international travel).  Females in the BP spectrum tend to experience postpartum depressions with greater frequency and tend to have worse premenstral upset (dysphoria). While there is no absolutely diagnostic presentations of depression which dictate a specific diagnosis, atypical depressive presentations tend to be more common in BP spectrum.  Atypical depressive presentations include increased appetite and weight gain, hypersomnia (more time in bed, more time sleeping, naps) and overwhelming fatigue sometimes called leaden paralysis.  Typical depressions usually manifest insomnia, agitation, and weight loss. In arriving at a diagnosis, it is important to take into account the course of illness over time.  Central to BP spectrum is hypomanic states which include irritability, talkativeness, and racing thoughts, increased energy and decreased need for sleep.  Often these can only be elicited by talking to family member as the patient often seems to seal off these episodes from consciousness. Finally, we shouldn't forget that these are highly heritable disorders.  Therefore, looking at the family tree is important especially at the first degree relatives.  There are studies that show that the risk of having a BP spectrum disorder goes up 10 fold if one has a bipolar parent.

McIntyre and colleagues found that medical comorbities were prevalent in BP spectrum patients. Epilepsy, multiple sclerosis, migraine, circulatory disorders, and metabolic syndrome are much more common in BP spectrum than in the general population. Metabolic syndrome is an constellation of deviations from health that include insulin resistance, central adiposity, elevated lipid lab profile, elevated BMI, and hypertension.  In BP spectrum patients metabolic syndrome is supported by unfavorable lifestyle (smoking, poor diet, physical inactivity) and the effects of treatments used to treat BP spectrum including atypical anti-psychotics and some mood stabilizers. Substance abuse is also common in BP spectrum.  By some estimates, 60% of bipolar spectrum patients have an alcohol abuse problem at some time during their life.

When I make the diagnosis of BP spectrum disorder, I present this as a statistical or probabilistic statement.  There is no test for bipolar disorder, no gene or genes have been identified as causative, no brain image that is diagnostic and therefore the certainty of the diagnosis is somewhat less that 100%.  Still, prompt diagnosis and treatment is crucial to securing a positive outcome for a patient which should offer the chance for a "normal" life.