- Email: [email protected]
Retinal nerve fiber layer thickness in posterior cortical atrophy and the visual variant of Alzheimer’s disease
Podium Presentations: Monday, July 20, 2015
0.93). The whole hypothalamus was subsequently segmented manually into five different subunits (Figure 1). Shape differences were investigated using the SPHARM-PDM toolbox. Results: The bvFTD group showed a 17% reduction in hypothalamic volume compared with controls (p<0.005, Mann-Whitney U test): right, mean 398 (standard deviation 62) versus 477 (38) mm3 and left, 385 (53) versus 467 (39) mm3, corrected for total intracranial volume. MAPT mutation carriers showed a trend for lower volumes on both sides compared with C9orf72 (12% difference). Specifically, in both shape and volumetric analyses, we found a strong evidence for the involvement of the dorsal tuberal hypothalamus in bvFTD patients, compared with controls (Figure 2). No significant correlations were found with the clinical scores. Conclusions: In summary, bvFTD patients showed lower hypothalamic volumes compared with controls: this reduction is localized to the subnuclei that regulate food intake, reward and perception of satiety. Moreover, different genetic mutations seem to have a differential impact on the hypothalamus. O2-10-05
RETINAL NERVE FIBER LAYER THICKNESS IN POSTERIOR CORTICAL ATROPHY AND THE VISUAL VARIANT OF ALZHEIMER’S DISEASE
Victoria Susan Pelak, Joel Eastes, University of Colorado School of Medicine, Aurora, CO, USA. Contact e-mail: [email protected] Background: Spectral domain optical coherence tomography (SD-
OCT) has proven to be a reliable means of measuring the thickness of the retinal nerve fiber layer (RNFL), a measure of central nervous system axonal health. Progressive RNFL thinning beyond expected for normal aging has been associated with Alzheimer’s disease (AD). Analysis of RNFL thickness has not been reported in Posterior Cortical Atrophy (PCA), a neurodegenerative disorder most commonly associated with AD pathology, or in the Visual Variant of Alzheimer’s disease (VVAD). Methods: We analyzed SD-OCT RNFL thickness profiles for 11 patients who met a clinical diagnosis of PCA or VVAD and compared results to matched, normative data from SD-OCT manufacturers. Results: For our group of PCA and VVAD patients, we found an average decrease in RNFL thickness that is similar to published reports for typical AD. Conclusions: RNFL loss in PCA and VVAD appears to be consistent with published reports for AD and suggests that the salient visual deficits associated with PCA and VVAD are not due to axonal loss of the retinal ganglion cells. Interestingly, the results do not reveal the degree of thinning that might be expected from ‘pathological neuronal spread’ of posterior cortical disease to the anterior visual pathway at the level of the RNFL. Longitudinal, case-control studies are necessary, however, to determine whether RNLF measures in syndromic variants of AD might be useful in the investigation of neuronal “spread” of disease. O2-10-06
FREQUENCY AND DISTRIBUTION OF CEREBRAL MICROBLEEDS IN DEMENTIA WITH LEWY BODIES
Lidia Sarro1,2, Ipek Gungor1,3, Jonathan Graff Radford1, Samantha M. Zuk1, Nirubol Tosakulwong1, Scott A. Przybelski1, Bradley Boeve1, Tanis J. Ferman4, Glenn E. Smith1, David S. Knopman1, Massimo Filippi2, Ronald C. Petersen1, Clifford R. Jack, Jr.1, Kejal Kantarci1, 1Mayo Clinic, Rochester, MN, USA; 2Scientific Institute and University Vita-Salute San Raffaele, Milan, Italy; 3Istanbul University, Istanbul, Turkey; 4Mayo Clinic, Jacksonville, FL, USA. Contact e-mail: [email protected] Background: Microbleeds (MBs) and superficial siderosis (SS) iden-
tified on T2* gradient recalled echo (GRE) and susceptibility weighted MRI are recognized as markers of cerebral microangiop-
P199
athy in older adults. The frequency and topography of cerebral MBs have not been extensively investigated in dementia with Lewy bodies (DLB). The purpose of this study was to determine the frequency and location of MBs in DLB in comparison with MBs in Alzheimer disease (AD) and cognitively normal controls (CN). Methods: Patients with probable DLB (n¼20) with median (IQR) age of 68 (64-73) years, who were consecutively recruited to the Mayo Clinic Alzheimer’s Disease Research Center (ADRC) and underwent 3T MRI examination with a T2* GRE scan were included. Age and sex matched patients with AD dementia (n¼38) from the ADRC and cognitively normal controls (CN; n¼83) from the population-based Mayo Clinic Study on Aging were included as referent groups. T2* GRE scans were assessed for the presence of MBs and SS. Frequency of MBs were compared among groups using Fisher’s exact tests. Results: A total of 7 DLB (35%), 19 CN (23%) and 8 AD (21%) subjects had at least one MB. A majority of the MBs were located in the frontal lobes in patients with probable DLB (57%), which was not different (p¼0.81) from the CN (42%) and AD groups (38%). No MBs were identified in the deep gray nuclei, capsular white matter and infratentorial regions in patients with probable DLB when compared to AD (p¼0.03) and CN (p¼0.14). SS was present in five (4%) of all the subjects (2 CN and 3 AD). Conclusions: MBs occur at a similar frequency in patients with probable DLB compared to AD dementia and CN. The distribution of MBs showed a characteristic regional pattern in patients with probable DLB, predominantly involving the frontal lobes. The deep gray nuclei, capsular white matter and infratentorial regions, which are thought to be more susceptible to the arteriolosclerosis-related MBs than cerebral amyloid angiopathy were not affected in probable DLB.
MONDAY, JULY 20, 2015 ORAL SESSIONS O2-11 EPIDEMIOLOGY: COGNITIVE RESERVE, EDUCATION, AND LONG-TERM EFFECT ON COGNITIVE CHANGE AND DEMENTIA INCIDENCE O2-11-01
DOES COGNITIVE RESERVE PROTECT AGAINST DEMENTIA AFTER A STROKE OR TIA? THE ROTTERDAM STUDY
Marileen L.P. Portegies, Saira Saeed Mirza, Albert Hofman, Henning Tiemeier, M. Arfan Ikram, Erasmus University Medical Center, Rotterdam, Netherlands. Contact e-mail: [email protected] Background: The cognitive reserve hypothesis proposes that persons with a higher cognitive ability built up earlier in life can cope with more neurodegenerative damage, before it becomes clinically apparent as dementia, compared to persons with a lower cognitive ability. However, it remains unclear if cognitive reserve also protects against dementia after cerebrovascular events such as stroke or transient-ischemic-attack (TIA). Therefore, we investigated whether cognitive reserve protects against dementia after stroke or TIA. Methods: Within the population-based Rotterdam Study, 9,352 participants free of prevalent stroke, TIA, and dementia were followed for occurrence of stroke, TIA and dementia. We investigated the associations of incident stroke or TIA with incident dementia, stratifying for educational level as a measure of cognitive reserve. Educational-level was categorized as low, intermediate and high. Cox proportional hazards models using incident stroke and TIA as time-varying covariates were used to test the associations.
0.93). The whole hypothalamus was subsequently segmented manually into five different subunits (Figure 1). Shape differences were investigated using the SPHARM-PDM toolbox. Results: The bvFTD group showed a 17% reduction in hypothalamic volume compared with controls (p<0.005, Mann-Whitney U test): right, mean 398 (standard deviation 62) versus 477 (38) mm3 and left, 385 (53) versus 467 (39) mm3, corrected for total intracranial volume. MAPT mutation carriers showed a trend for lower volumes on both sides compared with C9orf72 (12% difference). Specifically, in both shape and volumetric analyses, we found a strong evidence for the involvement of the dorsal tuberal hypothalamus in bvFTD patients, compared with controls (Figure 2). No significant correlations were found with the clinical scores. Conclusions: In summary, bvFTD patients showed lower hypothalamic volumes compared with controls: this reduction is localized to the subnuclei that regulate food intake, reward and perception of satiety. Moreover, different genetic mutations seem to have a differential impact on the hypothalamus. O2-10-05
RETINAL NERVE FIBER LAYER THICKNESS IN POSTERIOR CORTICAL ATROPHY AND THE VISUAL VARIANT OF ALZHEIMER’S DISEASE
Victoria Susan Pelak, Joel Eastes, University of Colorado School of Medicine, Aurora, CO, USA. Contact e-mail: [email protected] Background: Spectral domain optical coherence tomography (SD-
OCT) has proven to be a reliable means of measuring the thickness of the retinal nerve fiber layer (RNFL), a measure of central nervous system axonal health. Progressive RNFL thinning beyond expected for normal aging has been associated with Alzheimer’s disease (AD). Analysis of RNFL thickness has not been reported in Posterior Cortical Atrophy (PCA), a neurodegenerative disorder most commonly associated with AD pathology, or in the Visual Variant of Alzheimer’s disease (VVAD). Methods: We analyzed SD-OCT RNFL thickness profiles for 11 patients who met a clinical diagnosis of PCA or VVAD and compared results to matched, normative data from SD-OCT manufacturers. Results: For our group of PCA and VVAD patients, we found an average decrease in RNFL thickness that is similar to published reports for typical AD. Conclusions: RNFL loss in PCA and VVAD appears to be consistent with published reports for AD and suggests that the salient visual deficits associated with PCA and VVAD are not due to axonal loss of the retinal ganglion cells. Interestingly, the results do not reveal the degree of thinning that might be expected from ‘pathological neuronal spread’ of posterior cortical disease to the anterior visual pathway at the level of the RNFL. Longitudinal, case-control studies are necessary, however, to determine whether RNLF measures in syndromic variants of AD might be useful in the investigation of neuronal “spread” of disease. O2-10-06
FREQUENCY AND DISTRIBUTION OF CEREBRAL MICROBLEEDS IN DEMENTIA WITH LEWY BODIES
Lidia Sarro1,2, Ipek Gungor1,3, Jonathan Graff Radford1, Samantha M. Zuk1, Nirubol Tosakulwong1, Scott A. Przybelski1, Bradley Boeve1, Tanis J. Ferman4, Glenn E. Smith1, David S. Knopman1, Massimo Filippi2, Ronald C. Petersen1, Clifford R. Jack, Jr.1, Kejal Kantarci1, 1Mayo Clinic, Rochester, MN, USA; 2Scientific Institute and University Vita-Salute San Raffaele, Milan, Italy; 3Istanbul University, Istanbul, Turkey; 4Mayo Clinic, Jacksonville, FL, USA. Contact e-mail: [email protected] Background: Microbleeds (MBs) and superficial siderosis (SS) iden-
tified on T2* gradient recalled echo (GRE) and susceptibility weighted MRI are recognized as markers of cerebral microangiop-
P199
athy in older adults. The frequency and topography of cerebral MBs have not been extensively investigated in dementia with Lewy bodies (DLB). The purpose of this study was to determine the frequency and location of MBs in DLB in comparison with MBs in Alzheimer disease (AD) and cognitively normal controls (CN). Methods: Patients with probable DLB (n¼20) with median (IQR) age of 68 (64-73) years, who were consecutively recruited to the Mayo Clinic Alzheimer’s Disease Research Center (ADRC) and underwent 3T MRI examination with a T2* GRE scan were included. Age and sex matched patients with AD dementia (n¼38) from the ADRC and cognitively normal controls (CN; n¼83) from the population-based Mayo Clinic Study on Aging were included as referent groups. T2* GRE scans were assessed for the presence of MBs and SS. Frequency of MBs were compared among groups using Fisher’s exact tests. Results: A total of 7 DLB (35%), 19 CN (23%) and 8 AD (21%) subjects had at least one MB. A majority of the MBs were located in the frontal lobes in patients with probable DLB (57%), which was not different (p¼0.81) from the CN (42%) and AD groups (38%). No MBs were identified in the deep gray nuclei, capsular white matter and infratentorial regions in patients with probable DLB when compared to AD (p¼0.03) and CN (p¼0.14). SS was present in five (4%) of all the subjects (2 CN and 3 AD). Conclusions: MBs occur at a similar frequency in patients with probable DLB compared to AD dementia and CN. The distribution of MBs showed a characteristic regional pattern in patients with probable DLB, predominantly involving the frontal lobes. The deep gray nuclei, capsular white matter and infratentorial regions, which are thought to be more susceptible to the arteriolosclerosis-related MBs than cerebral amyloid angiopathy were not affected in probable DLB.
MONDAY, JULY 20, 2015 ORAL SESSIONS O2-11 EPIDEMIOLOGY: COGNITIVE RESERVE, EDUCATION, AND LONG-TERM EFFECT ON COGNITIVE CHANGE AND DEMENTIA INCIDENCE O2-11-01
DOES COGNITIVE RESERVE PROTECT AGAINST DEMENTIA AFTER A STROKE OR TIA? THE ROTTERDAM STUDY
Marileen L.P. Portegies, Saira Saeed Mirza, Albert Hofman, Henning Tiemeier, M. Arfan Ikram, Erasmus University Medical Center, Rotterdam, Netherlands. Contact e-mail: [email protected] Background: The cognitive reserve hypothesis proposes that persons with a higher cognitive ability built up earlier in life can cope with more neurodegenerative damage, before it becomes clinically apparent as dementia, compared to persons with a lower cognitive ability. However, it remains unclear if cognitive reserve also protects against dementia after cerebrovascular events such as stroke or transient-ischemic-attack (TIA). Therefore, we investigated whether cognitive reserve protects against dementia after stroke or TIA. Methods: Within the population-based Rotterdam Study, 9,352 participants free of prevalent stroke, TIA, and dementia were followed for occurrence of stroke, TIA and dementia. We investigated the associations of incident stroke or TIA with incident dementia, stratifying for educational level as a measure of cognitive reserve. Educational-level was categorized as low, intermediate and high. Cox proportional hazards models using incident stroke and TIA as time-varying covariates were used to test the associations.