DISEASE
Although the cause(s) of Parkinson's Disease remain largely unknown, the mechanism of the disease is the best understood in neurology.
Here we see a man with Parkinson's by the late great Frank Netter, M.D. - for one pass learning there's no one better than Netter.
After several years, the classic stooped posture and shuffling gait are unmistakeable, but like Multiple Sclerosis (especially before MRI'S) and ALS, this condition is often undiagnosed for a long time, sometimes years. One of the best early signs is a lack of armswing on one side (PD is bilateral but often begins unilaterally "clumbsiness" in one arm and/or leg drag) but I don't think any harm comes from delayed diagnoses....not until we have a truly neuroprotective agent. That was the early promise of Eldepryl (Deprenyl), that it might protect remaining dopaminergic neurons. The consensus now is generally "no."
In the 1960's and 70's the brains of human victims of the disease were compared to "control" brains. Tissue was extracted from different parts of the brain, emulsified and chemically analyzed. Cotzias, among others, confirmed the central fact of Parkinson's Disease: the substantia nigra, two very distinct clusters of neurons, visibly lose their black pigmentation and, chemically, their dopamine.
This slice of human midbrain
has been stained for myelin so that
black and white are completely reversed.
The symmetrical white bands are visibly black at autopsy
(see illustration below)
(from Structure of Human Brain, DeArmond et al, Oxford Press, 1989)
The confirmation that one missing neurotransmitter in one functional brain system was galvanizing and led almost overnight to giving dopamine to Parkinson's patients and the rest is history - and a Nobel Prize for Cotzias. (It also led to yet another "nouvelle vague" of psychiatric mythologizing, this one, replete with abracadabra about neurotransmitters has been perfectly identified by Tom Szasz as NEUROMYTHOLOGY. But that's another story.)
I have nothing new to add to the Parkinson's story. Very active investigation of this disease is taking place. But I can add 20 years of clinical experience, a brief summary of which follows:
1) Sinemet remains the best drug by far. I'm not so impressed with the extended release form.
2) Sooner or later, 5-10 years from diagnosis (7-10 from onset), diminishing returns and increasing side effects occur.
3) After the initial benefit, patients - who remain, for the most part, mentally intact - are understandably frustrated and frightened and go doctor shopping.
4) Attempts to increase dose or add other dopaminergic agents lead to fully-formed visual hallucinations, nightmares, involuntary twisting movements of hands, feet and face (dyskinesias), and "freezing" (on/off) episodes.
5) Exercise and activity are essential. There appears to be an inertia of willpower - it takes more of an effort to get up and get going - but do it.
(From an Introduction to Neuropathyology, Adams and Graham, Churchill Livingstone, 1988)
6) Avoid dopamine-blocking agents which include the entire category of neuroleptics (major tranquilizers such as Haldol), some anti-depressants and even Compazine. All of these can produce transient or permanent syndromes similar to Parkinson's. All of them block the very neurotransmitter already depleted in Parkinson's - dopamine. All of them are being widely used.
7) I'd be wary of surgery because the basal ganglia (the upstream connection to the substantia nigra) are a very small target and very close to motor fibers which, if affected, can leave one previously Parkinsonian side paralyzed.
8) However, Desperate illnesses desperate remedies demand, and as long as we have any vestige of autonomy left in medicine, I applaud the sincere efforts being made by individual doctors and patients willing to experiment.
9) Parkinson's is not a fictitious mental illness. It is real and disabling leaving the victim a prisoner in their bodies. The prevalence is certainly increasing as the population ages and many, including me, are suspicious of environmental toxins. Consider: after spreading petrochemicals all over the place from cars to plastics to the ozone, we're now systematically introducing them into our brains in the form of psychoactive drugs - legal and illegal. Almost all of the legal drugs are brand new on the planet and almost all are derived from starting ingredients such as Toluene which come from oil. With all that oil coming up out of the ground it was inevitable. The smell of the lotus comes off on the hands.
Questions? Comments? Write me at DrJohn@idiom.com
