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Family history of dementia is a risk factor for LBD
This is a short article from the journal Neurology about a year ago. The authors conclude that a family history of dementia is more common in autopsy-confirmed LBD than in (living) healthy "controls." That's probably enough info for nearly all of you. (A few of you, interested in APOE4, may want to read the excerpts.) I'm copying below the abstract and some excerpts.
Neurology. 2006 Jun 27;66(12):1949-50.
Family history of dementia is a risk factor for Lewy body disease.
Woodruff BK, Graff-Radford NR, Ferman TJ, Dickson DW, DeLucia MW, Crook JE, Arvanitakis Z, Brassler S, Waters C, Barker W, Duara R.
Department of Neurology, Mayo Clinic Scottsdale, 13400 East Shea Boulevard, Scottsdale, Arizona 85259, USA.
Genetic factors are important in Alzheimer disease (AD) and Parkinson disease but have not been well characterized in Lewy body dementia (LBD). The authors obtained family history in patients from an autopsy series of AD and LBD and in living healthy controls. A family history of dementia was more common in both LBD and AD compared with controls, suggesting that genetic factors are as important in LBD as they are in AD.
PubMed ID#: 16801670
"Several reports identify specific mutations causing AD, PD, and LBD. Other genetic factors influence risk of developing disease, such as the APOE epsilon4 allele in AD."
"A recent case-control study of PD did not demonstrate an increased risk of AD in relatives of PD patients compared with controls, suggesting separate genetic factors for these two conditions."
"We mailed questionnaires to relatives of patients with pathologically confirmed AD and LBD. ... There was a 71% return rate for the questionnaires."
"We identified patients with AD lacking Lewy body pathology (n=70) and a group with transitional or diffuse LBD with Braak neurofibrillary tangle stages of 4 or less (n=18). In this cohort, Lewy body pathology was considered to be mainly responsible for the clinical syndrome. It is common for patients in this age group to have mild amyloid or tau-related pathology without clinical manifestations of AD. Only one patient with LBD had no AD pathology (Braak Stage 0), and this patient did have a family history of dementia. Two groups with AD (Braak neurofibrillary tangle stage of greater than 4) were identified with mixed pathology, including those with Lewy bodies confined to the amygdala (n=14), and those with transitional or diffuse LBD (n=23). The latter groups with mixed pathology were not included in the family history analysis because the family history of dementia could be related to both the Alzheimer and Lewy body pathology."
"We obtained APOE genotype in a subset of the autopsy cases (48 AD cases and 13 LBD cases) and living controls (n=56) using standard methods."
"The preponderance of males in the LBD group is a well-recognized phenomenon."
"Thirty-four (49%) of the AD cases had a positive family history of dementia or memory problem, compared with 12 (67%) of the LBD cases and 8 (13%) of the control cases."
"In the mixed pathology group, 64% of the 14 patients with Lewy bodies confined to the amyygdala had a family history of dementia, compared with 57% in the group with transitional or diffuse LBD."
"The frequency of the APOE epsilon4 allele was 33% in AD, 15% in LBD, and 9% in the control group."
"After adjusting for age and sex, there was no evidence of a difference in the frequency of family history of dementia between LBD and AD cases (p=0.17)."
"After adjusting for age, sex, and diagnosis type, there was no overall evidence of a relationship between the number of epsilon4 alleles and family history of dementia."
"Discussion. ...(A) family history of dementia is at least as common in LBD as in AD. The APOE epsilon4 allele does not seem to confer this genetic susceptibility in this small group of LBD patients. This suggests that other genetic factors may influence the development of LBD..."
"This study is limited by the small sample size and the use of controls without pathology confirmation."