Dementia: Lewy Body vs Parkinson’s Disease

Rodolfo Savica, MD, MSc Department of Neurology, College of Medicine Division of Epidemiology, Department of Health Sciences Research, College of Medicine, Mayo Clinic, Rochester, MinnesotaMedicalResearch.com Interview with:
Rodolfo Savica, MD, MSc
Department of Neurology, College of Medicine
Division of Epidemiology, Department of Health Sciences Research, College of Medicine, Mayo Clinic, Rochester, Minnesota

 

MedicalResearch.com: What are the main findings of this study?

Dr. Savica: This study is the first in North America to explore the incidence of DLB and PDD in a population based sample. We found that the overall incidence of dementia with Lewy bodies (DLB), considered the second leading cause of neurodegenerative dementia after Alzheimer`s disease, is lower than that of Parkinson`s disease (PD), increases steeply with age, and is markedly higher in men than in women.

We used the unique population-based medical records linkage system of the Rochester Epidemiology Project, in Olmsted County, MN.

In particular, the overall incidence of Parkinson Disease Dementia (PDD) was 2.5 cases per 100,000 person-years; whereas the incidence of Dementia with Lewy Bodies (DLB) was 3.5 cases per 100,000 person-years. At, the incidence of Parkinson Disease (14.2 cases per 100,000 person-years) was 4-fold higher than DLB and 2.4 times higher than the incidence of DLB and PDD combined. In addition we found that the incidence of DLB was higher in men than in women; whereas PDD was similar across sexes.

Furthermore we identified a series of differences in the clinical symptoms between DLB and PDD: DLB cases presented more hallucinations (62.5% vs 20.0%; p˂.001), more cognitive fluctuations (25% vs 8.9%; p.03) and, although not statistically significant, more myoclonus (12.5% vs 4.4%; p=.15).

MedicalResearch.com: Were any of the findings unexpected?

Dr. Savica: We were somehow surprised that PDD is less common that expected. PDD is also less common than DLB.

MedicalResearch.com: What should clinicians and patients take away from your report?

Dr. Savica: The differences in the clinical features may be extremely important to differentiate between DLB and PDD. This information will be extremely helpful to clarify the correct diagnosis and to guide therapeutic interventions that may be different diseases and sexes.

MedicalResearch.com: What recommendations do you have for future research as a result of this study?

Dr. Savica: This study is a starting point to highlight and expand the research on DLB and PDD. We have a number of studies already in completion that will provide further help to patients, clinicians and scientist that are involved in DLB and PDD care.

Citation:

Incidence of Dementia With Lewy Bodies and Parkinson Disease Dementia

Savica R, Grossardt BR, Bower JH, Boeve BF, Ahlskog J, Rocca WA. Incidence of Dementia With Lewy Bodies and Parkinson Disease Dementia. JAMA Neurol. 2013;():-. doi:10.1001/jamaneurol.2013.3579.