The Ash Twins Blog

People are curious about the validity of psychiatric diagnoses. For the psychiatric disorders, there are no objective tests (like a blood concentration or imaging finding) to reliably confirm a diagnosis. Instead, psychiatrists look for characteristic patterns of symptoms to make their diagnoses. The most popular source for diagnostic criteria on psychiatric disorders is the Diagnostic and Statistical Manual, edition IV, DSM-IV for short. The DSM-IV operationalizes the diagnosis of psychiatric disorder based on symptoms which tend to cluster together. For example, someone with major depressive disorder must have 5/9 depressive symptoms (depressed mood, changes in sleep patterns, decreased interest in or pleasure from activities of life, guilt feelings, decreased energy, inability to concentrate, changes in weight or appetite, increase or decrease in spontaneous movements [called psychomotor agitation/retardation], and suicidal ideation) for over 2 weeks. These criteria are created for research purposes (to be able to directly compare different studies) and are based in clinical studies of common symptoms. For many psychiatric disorders, there is not a lot of good research to objectively define or assess the validity of diagnostic criteria.

For schizophrenia, the DSM-IV criteria are two or more of the following symptoms:

1. delusions – beliefs that have no basis in reality which are held despite evidence to the contrary
2. hallucinations – seeing, hearing, or feeling things that aren’t there
3. disorganized speech – saying random things; no logical thought process
4. disorganized or catatonic behavior – e.g. staring at the wall without responding to external stimuli
5. Negative symptoms – no spontaneous speech, flat affect (schizophrenics’ faces often look like a mask), avolition

Only one symptom is required if the delusions are bizarre (i.e. “The CIA has implanted a microchip in my brain so that aliens can control my thoughts”) or the hallucinations consist of a running commentary of voices or voices conversing with each other. The symptoms must cause significant occupational impairment. It’s called schizophrenia if symptoms last over 6 months, schizophreniform disorder if symptoms last between 1 and 6 months, and brief psychotic episode if under 1 month.  There are five subtypes of schizophrenia, with paranoid – which predicts prominent hallucinations and delusions – being the most common. Add mood symptoms (like depression or mania [which have their own DSM criteria]) and you call it schizoaffective disorder.

It is estimated that a bit less than 1% of the population suffers from schizophrenia. It has a strong genetic component, as 10% of siblings of schizophrenics also have schizophrenia, and 46% of individuals with two parents with schizophrenia or an identical twin with schizophrenia also develop schizophrenia. 14% of individuals with a nonidentical twin with schizophrenia also develops schizophrenia, suggesting a role for in utero predisposing insults. The prevalence is the same world-wide, and no significant environmental predisposing factors have been identified. Symptoms first begin to develop in the early- to mid-twenties, with males presenting a few years earlier than females. These facts confirm that schizophrenia is a definite biological disease.

The diagnosis of schizophrenia, unfortunately, is still as much an art as a science. The DSM-IV criteria have been severely criticized: To cite on example, if a patient’s delusions are bizarre, that one symptom is enough to diagnose schizophrenia, but the definition of bizarre is vague, and there is poor inter-rater reliability in categorizing delusions as bizarre or nonbizarre. It is difficult to assess the reliability of DSM IV diagnosis, because there is no “gold-standard” test to verify that someone has schizophrenia. In assessing a diagnostic test for Alzheimer disease, in contrast, one could verify the test postmortem by looking at brain tissue under a microscope – Alzheimer neurons are blighted with amyloid plaques and neurofibrillary tangles. For schizophrenia, the best we can do is check in with diagnosed patients several years later and see if they have gotten worse, as schizophrenia tends to be a chronic progressive disease. Using this criteria, the DSM has a 93% specificity and 51% sensitivity for diagnosis of schizophrenia in first-episode psychotics. In other words, only 7% of patients were incorrectly diagnosed with schizophrenia (false-positives), but 49% with schizophrenia were not diagnosed as such (false-negatives). This experiment is but one of many: there have been dozens of studies testing the reliability of schizophrenia diagnosis, each one using different experimental parameters. Jansson and Parnas review them here.

The differential diagnosis of schizophrenia is complex. Duration of symptoms differentiates schizophrenia from schizophreniform disorder (as above). If only delusions are present, and these are nonbizarre (“I know my spouse is cheating on me”) the diagnosis is delusional disorder. Substance toxicity (especially cocaine and PCP) can cause psychosis: these are differentiated with drug tests and by detox. Neurological disorders (defined by visible brain pathology) like dementia, tumors, epilepsy, or encephalitis can also present with psychosis.

The patient I mentioned in the previous post, for example, presented with prominent running-commentary hallucinations and bizarre delusions, little or no negative symptoms, and a history of alcoholism. To make the diagnosis given the clinical information, we would do a CT and a drug test to rule out organic brain pathology and substance toxicity. Alcohol toxicity is an unlikely cause, because it usually presents with slurring of speech, confusion, and loss of consciousness – hallucinations and delusions are not prominent. Alcohol withdrawal , on the other hand, can cause visual and audial hallucinations, but these rarely if ever include running commentaries, and other withdrawal symptoms (like autonomic dysfunction and delirium tremens) would also be prominent. The characteristic presentation of alcohol-induced dementia, sometimes associated with Wernicke-Korsakoff syndrome, includes symptoms of memory loss, aphasia, and disorganized cognition – again, psychotic symptoms are rare.

After ruling out other causes of psychosis, the standard of care is to attempt treatment. If antipsychotic medicines work, and the patient reports a significant drop in symptoms, the diagnosis is likely correct. Psychiatrists can never be sure, though, so a healthy dose of skepticism about previously-diagnosed psychiatric disorders is always warranted. If a patient presents with psychosis but does not fit any of the defined categories, he or she can be labeled ‘psychotic disorder not otherwise specified.’

And patient reliability is also an issue. The DSM-IV classification of Malingering is “the intentional production of false or grossly exaggerated physical or psychological symptoms motivated by external incentives, such as avoiding military conscription or duty, avoiding work, obtaining financial compensation, evading criminal prosecution, obtaining drugs, or securing better living conditions” (Andreasen & Black 2006). The patient mentioned in the previous post, for example, could be faking his symptoms so that VA social workers would help him find a new place to live. Malingering is suspected when the patient stands to benefit from a specific diagnosis (i.e. patient is referred by an attorney), the symptoms reported are vague or contradictory, there is a marked discrepancy between patient’s subject symptoms and objective signs, or the patient has antisocial personality disorder. In this patient’s case, given his extended history of psychotic symptoms which dovetail exactly with the diagnostic criteria for schizophrenia, I find it unlikely that he is malingering, but if he has studied the DSM, he could theoretically have fabricated his entire presentation. There’s no way to know.

Last Monday, a middle-aged white male with a history of paranoid schizophrenia and alcohol dependence was admitted to the psych ward for passive suicidal ideation. I was sent to interview him.

He told me that his living situation had become “intolerable”: the other people living there were “rough characters” and there were a lot of “negative vibes” – “it’s a tough place”. It became so intolerable, in fact, that on Saturday he left the alcohol rehab center he lived in, checked into a motel down the street, and chugged a 1.5 liter bottle of Listerine (“It’s about 50 proof” he told me). The minty elixir knocked him out until the next day, at which point he staggered home. On Monday morning he came to the hospital and told his psychiatrist that he felt like the world would be better off without him. He was admitted for observation.

I had a long talk with the patient about his symptoms. Most notably, he hears thousands of voices in his head all day ever day. Some voices are good and some are bad. They  give a running commentary of things going on around him and talk to him about his “telepathy.” When asked about it, he says “yeah, I think I have telepathy. Maybe it’s the next stage in evolution or something. I don’t know.” He can read minds and feels that others can read his thoughts (it’s called ‘thought broadcasting’ in the textbook).

He has intricate and complicated visual hallucinations, too – the previous night, for instance, he saw himself wearing a golden breast plate with the 12 tribes of Israel burnished upon it. He called his visions “crazy” and “disgusting.” Some days he wakes up as figures from the bible, like Isaiah or Abraham, and he relives their religious adventures. He thinks he might have multiple personality disorder (called dissociative identity disorder in the DSM).

He is the highest-functioning schizophrenic I’ve met, and he’s a great story teller. If you met this guy in a store or at a bar, you would never know that he has thousands of voices roaring in his head. I had high hopes for him. Then I talk to my attending and the social worker on my team. They say he has been admitted dozens of times for the same thing. In fact, the patient left out a very important detail in the interview: he’s the Antichrist. He has a powerful demon living inside him, which he performs strange rituals to kill (like drinking Listerine – this is not the first time he has done that). One time, the doctor said, they sobered him up and discharged him, and he immediately got drunk and rolled around in an ant hill. He was readmitted the next morning, this time covered in ant bites. In fact, he has been kicked out by virtually every shelter and rehab center in the city. It was hard to believe we were talking about the same guy.

The next day, the patient reported that the volume of the voices had been turned way down. I asked him about the demon inside him, but he refused to elaborate: “Yeah, yeah.. how about we let sleeping dogs lie.” I see him every day on rounds and ask him how he’s doing, how are the meds working, are there any side effects, what’s his plan after discharge.

He is full detoxed from alcohol, he denies thoughts of hurting himself or others, and his hallucinations are relatively stable. He won’t even go back to his former home to get his belongings, he says, and he has another communal home in mind. We will discharge him later this week.

I started my clinical rotation in psychiatry this month, and my first assignment is at the Veteran’s Affairs inpatient psych ward.  I’m seeing some very interesting things, and I’ll try to describe them on the blog.

For example, the first patient I saw was a 23-year-old veteran of the Iraq war (they are labeled ‘OIF’ on the chart, for Operation Iraqi Freedom) who had his psychotic break during an ugly situation in Iraq last year (note: The average age of onset of schizophrenia is 23, and psychological trauma is a common precipitating event). He’s now diagnosed with schizophrenia, and he’s on permanent military disability – the government will give  him $3,000 a month for the rest of his life, a thank-you for serving the country, and a we’re-sorry for precipitating a chronic disabling mental illness. The problem is that he lives with his mother and has no expenses, so he has 3,000 bucks every month to blow on blow. Dealers come to his house at the beginning of every month to sell him crack cocaine; being schizophrenic, he has trouble saying no.

Cocaine induces dopamine release in the limbic forebrain, leading to its euphoric effects and addictive potential. The limbic forebrain dopaminergic pathway is the same neurotransmitter system which appears to be deranged in schizophrenia (we know this because conventional antipsychotics, like haloperidol [haldol] or chlorpromazine [thorazine] are antagonists at the D2 dopamine receptor, which are abundant in the mesolimbic pathway and nigrostriatal pathway [the pathway that atrophies in Parkinson's disease leading to difficulty initiating new movements -- side effects of the conventional antipsychotics can look like Parkinson disease]).  As such, cocaine intoxication can induce psychotic episodes in schizophrenics. At the beginning of every month (this time he came in on January 4th), our patient comes in with active psychosis, reading people’s minds, seeing people in the room that don’t exist, etc.

The situation questions the practicality of giving this guy such a big allowance, even with his tragic military experience. In his case, the more money he receives from Veteran’s Affairs, the worse his situation would become. Fortunately, a solution was in the works – Social Work was in the process of rerouting his “fiduciary” to his mother.

Over the next few days, we stabilized his symptoms with antipsychotic medication. We scheduled a consultation for rehab options and discharged him to his mother.

And that was just my first patient. More to come.