Table 3. Clinical Features/Diagnoses in Residents of Olmsted County, Minnesota Who Are Participants in an Aging and Dementia Research Program and Had PSG-Proven RBD on January 1, 2008^*.

Primary clinical diagnoses	N
Normal neurologic functioning (idiopathic RBD)	8
Mild cognitive impairment (MCI)	2
MCI plus mild parkinsonian signs	2
Parkinson's disease with MCI	1
Dementia with Lewy bodies (DLB)	7
TOTAL	20

Population of Olmsted County, Minnesota on 1/1/08 – approximately 100,000

20/100,000 = 0.02% = absolute minimum point prevalence of PSG-proven RBD

3 additional participants (2 with Parkinson's disease and 1 with DLB) have classic features of RBD but no REM sleep was attained on PSG; thus RBD is suspected (ie, probable RBD) but was not confirmed on PSG

Table 3. Clinical Features/Diagnoses in Residents of Olmsted County, Minnesota Who Are Participants in an Aging and Dementia Research Program and Had PSG-Proven RBD on January 1, 2008*.

Table 3. Clinical Features/Diagnoses in Residents of Olmsted County, Minnesota Who Are Participants in an Aging and Dementia Research Program and Had PSG-Proven RBD on January 1, 2008^*.