He’s down to 117 pounds and he used to weigh 150. His hands form the large belly he had. The doctor across from him cautions him not to lose anymore. He had been a borderline diabetic, and now he no longer has that diagnosis. Dyskinesias rock him in the seat but his is undeterred, and he asks the doctor whether decreasing the dose of Sinemet will help conserve his existing dopamine-producing neurons.
Behind the desk the physician responds, saying that Sinemet had at one time been thought to be detrimental to the neurons that produce dopamine. Scientists had thought levodopa might have a toxic affect on the dwindling population, but that idea has been discarded based on research that has shown that advancing illness affects other neurotransmitters, in addition to dopamine. The doctor even states some think that the levodopa gets converted to dopamine in the brain may actually have some protective value on the declining population of dopamine-rich neurons.
The doctor reviews the note he wrote after the previous visit. The only new presently available progress for patients with Parkinson’s disease is the Neupro patch. The company has said the patch would be available soon. For more than a year patients have been told that news. Now it seems it will be released in July. The patch provides a dopamine agonist that is taken up through the skin, at a steady rate for twenty-four hours. The method of absorption bypasses the digestive system. A dopamine agonist will not compete with dietary proteins for entry to the brain. The alternate source of dopamine will allow the patient to reduce the Sinemet he takes, thereby reducing the dyskinesias.
The doctor checks the rigidity in his arms and finds none. The patient is completely on. His joints are supple. He’s brought in a page of questions for the doctor. His handwriting is large and loose, atypical for a PD patient. He wonders whether he is taking too much vitamin D; 4000 mg per day. The doctor isn’t clear on the current information on the vitamin, it seems to be always changing.
An article by Salynn Boyles at Web MD health news from March of 2011, notes a study of patients with PD
found a high prevalence of vitamin D insufficiency, though levels did not continue to decline as the disease progressed.
The research is one suggesting a link between low vitamin D levels and Parkinson’s disease. A study from Finland published in 2010, showed people with the lowest levels of vitamin D were significantly more likely to develop Parkinson’s over almost three decades of follow-up, compared to people with the highest blood levels of the vitamin.
It’s not clear if vitamin D insufficiency raises Parkinson’s risk or if having high levels of the vitamin is protective, says study researcher Marian L. Evatt, MD, of Emory University School of Medicine and the Atlanta Veterans Affairs Medical Center.
“More research is needed to figure this out,” she tells WebMD. “There is certainly an association, but we can’t say if it is causal.”
In the newly published study, researchers examined the prevalence of vitamin D insufficiency in untreated patients with early Parkinson’s disease. They found 69.4% of patients had vitamin D insufficiency and 26% had vitamin D deficiency.