Linking restless legs syndrome with Parkinson's disease: clinical, imaging and genetic evidence
Copied from The Northwest Parkinson's Foundation News Update.
Tasneem PeeraullyEng-King Tan
7th Space Interactive - Restless legs syndrome (RLS) and Parkinson's disease (PD) are both common neurological disorders. There has been much debate over whether an etiological link between these two diseases exists and whether they share a common pathophysiology.
Evidence pointing towards a link includes response to dopaminergic agents in PD and RLS, suggestive of underlying dopamine dysfunction in both conditions. The extrastriatal dopaminergic system, in particular altered spinal dopaminergic modulation, may be variably involved in PD patients with RLS symptoms.
In addition, there is now evidence that the nigrostriatal system, primarily involved in PD, is also affected in RLS. Furthermore, an association of RLS with the parkin mutation has been suggested.
The prevalence of RLS has also been reported to be increased in other disorders of dopamine regulation. However, clinical association studies and functional imaging have produced mixed findings.
Conflicting accounts of emergence of RLS and improvement in RLS symptoms after deep brain stimulation (DBS) also contribute to the uncertainty surrounding the issue. Among the strongest arguments against a common pathophysiology is the role of iron in RLS and PD.
While elevated iron levels in the substantia nigra contribute to oxidative stress in PD, RLS is a disorder of relative iron deficiency, with symptoms responding to replacement therapy. Recent ultrasonography studies have suggested that, despite overlapping clinical features, the mechanisms underlying idiopathic RLS and RLS associated with PD may differ.
In this review, we provide a concise summary of the clinical, imaging and genetic evidence exploring the link between RLS and PD.
About Lewy Body disease
Copied from The Northwest Parkinson’s Foundation Weekly News Update
Lewy Body disease — sometimes known as Lewy Body dementia or Lewy Bodies disease — is one of four types of dementia that can develop with Parkinson’s disease, said Dr. Wolcott Holt, a neurologist with Essentia Health.
Duluth News Tribune - Lewy Body disease — sometimes known as Lewy Body dementia or Lewy Bodies disease — is one of four types of dementia that can develop with Parkinson’s disease, said Dr. Wolcott Holt, a neurologist with Essentia Health.
Lewy bodies are deposits in the nuclei of brain cells that typically occur with Parkinson’s disease, Holt said. Generally, they are confined to a small area of the brain, but in Lewy Body disease they occur throughout the brain. Although the cause of Parkinson’s is known, the cause of Lewy bodies isn’t, he said.
Symptoms can include Parkinson’s-like movements and tremors, suddenly falling asleep, hallucinations and progressive dementia, usually starting with memory loss, Holt said. There’s usually a distinct change in personality.
Of the symptoms Holt mentioned, Sharon DeLeo said she didn’t see any sleep disorders in her husband, David DeLeo, except those caused by medication.
All forms of dementia, except those caused by multiple strokes, are considered fatal diseases, Holt said. Lewy Body disease usually progresses more quickly than Alzheimer’s, typically in six to eight years after symptoms are noted, Holt said. Alzheimer’s typically runs its course in eight to 10 years.
Lewy Body is the second- or third-leading cause of dementia in adults older than 65, Holt said, but it’s not nearly as common as Alzheimer’s. The Lewy Body Dementia Association, on its website, says 1.3 million people in the United States have the disease. But it says it may be underdiagnosed by being mistaken for Alzheimer’s.
Nonetheless, it can be difficult to diagnose, Holt said.
“You know your loved one’s changing but you have no idea, and it may not be recognizable to general physicians that this is something going on,” he said. “You get psychometric testing, you get MRIs. The problem is those things don’t necessarily show it. They’re not specific enough.”
Experimental MRIs are starting to be used that may reveal Lewy bodies, he said. But currently the diagnosis can’t be confirmed until the patient’s autopsy takes place. And about 20 percent of the time, it turns out the Lewy Body diagnosis was wrong, Holt said.
More information about Lewy Body disease is available at the Lewy Body Dementia Association website: lbda.org