- Email: [email protected]
How does higher bmi preserve cognition among older adults? a 12-month exploratory neuroimaging study
P676
Poster Presentations: P3
(GDS) (p<0.0001), younger age (p¼0.003), and better socioeconomic status (Hollingshead) (p¼0.001) were associated with greater Purpose in Life (R2¼0.29, p<0.0001 for the overall model). The cognitive factor scores were not retained in the model. In the second model, greater FDG metabolism (p¼0.008), younger age (p¼0.03), and better socioeconomic status (p<0.0001) were associated with greater Purpose in Life (R2¼0.12, p<0.0001 for the overall model). Other imaging biomarkers and interactions were not retained in the model. Conclusions: Our findings support a relationship between fewer depressive symptoms and greater Purpose in Life. Moreover, the association of Purpose in Life with greater FDG metabolism, a marker of brain reserve, suggests that Purpose in Life may be an indicator of both better mental health and brain function.
P3-136
spective fMRI study with 66 seniors aged 70 to 80 years; 24 normal weight (with BMI18.50), 26 overweight (with BMI between 18.5 and 29.99), and 15 obese (with BMI 30.00). Participants performed a finger tapping task during fMRI scanning. Clinical measures of executive functions were assessed at baseline and 12 months. Results: After adjusting for baseline performance measure, comorbidity, gender, and age, obese individuals showed decreased task-related connectivity in the default mode network (DMN;
HOW DOES HIGHER BMI PRESERVE COGNITION AMONG OLDER ADULTS? A 12-MONTH EXPLORATORY NEUROIMAGING STUDY
Chun Liang Hsu1,2, Michelle W. Voss3, John R. Best1,4, Todd C. Handy1, Kenneth Madden1, Teresa Liu-Ambrose1,4, 1University of British Columbia, Vancouver, BC, Canada; 2Djavad Mowafaghian Center for Brain Health, Vancouver, BC, Canada; 3University of Iowa, Iowa City, IA, USA; 4Djavad Mowafaghian Centre for Brain Health, Vancouver, BC, Canada. Contact e-mail: [email protected]
Figure 1. Bonferroni-Corrected Task-State Group Contrast Map Highlighted areas show regions where Normal > Obese in DMN functional connectivity (p<0.006) during finger tapping.
Background: Obesity and dementia are both increasing in prevalence worldwide. While obesity are associated with key vascular risk factors (e.g., hypertension, diabetes) for dementia, the relationship between body fat and cognitive function in older adults remain equivocal. In fact, there is evidence body fat may be neural-protective for older adults. Neuroimaging studies of otherwise healthy adults demonstrate that increased body mass index (BMI) is associated with global and regional brain atrophy, as well as altered functional connectivity. However, few studies to date have investigated neural mechanisms of obesity-induced cognitive changes in older adults. In a 12-month prospective study, we aimed to examine: 1) the impact of BMI on functional brain connectivity; and 2) the role of functional brain connectivity in the association between BMI and cognitive function. Methods: A 12-month proTable 1A Partial Correlations of Connectivity and Cognitive Outcome Measures DMN Connectivity During Finger Tapping Variables
Pearson’s r
p-value
Digit Span Test at 12-Month Stroop Test at 12-Month Trail Making Test at 12- Month
0.30 -0.25 -0.16
0.02 0.85 0.25
*Controlled for baseline FCI, baseline mean ABC, baseline age, and baseline gender.
Figure 2. Direct and Indirect Effects of the Proposed Mediation Model
Table 1B Partial Correlations of Baseline BMI, Network Connectivity, and Cognitive Outcome Measures
Baseline BMI
DMN Finger Tapping
Digit Span Test 12-Month
StroopTest 12- Month
Trail Making Test 12-Month
Pearson’s r
p-value
Pearson’s r
p-value
Pearson’s r
p-value
Pearson’s r
p- value
-0.45
0.001
0.013
0.93
-0.06
0.67
0.17
0.22
*Controlled for baseline FCI, baseline mean ABC, baseline age, and baseline gender.
Poster Presentations: P3
p<0.006), which was significantly correlated with Digit Span Test performance (i.e. working memory) at 12 months (p<0.02) and BMI (p<0.001). Conclusions: Supporting evidence that report older individuals with higher BMI had less observable amyloid deposition within the DMN, we found elevated BMI indirectly lead to lower task-state DMN connectivity, which, in turn, lead to better performance on Digit Span Test. This suggests DMN connectivity mediates and suppresses the effect of BMI on cognitive function, and may be involved in compensatory processes in older adults.
P3-137
MICROSTRUCTURAL WHITE MATTER INTEGRITY AND RISK OF MORTALITY
Sanaz Sedaghat, Lotte G. M. Cremers, Marius de Groot, Albert Hofman, Aad van der Lugt, Oscar H. Franco, Abbas Dehghan, M. Arfan Ikram, Meike W. Vernooij, Erasmus MC, Rotterdam, Netherlands. Contact e-mail: [email protected] Background: While several studies reported a link between presence of white matter lesions and shorter survival, it is not yet clear whether this link extends to more subtle cerebral white matter changes. We investigated the independent association of cerebral white matter microstructural integrity with mortality. Methods: We included 4294 stroke and dementia free individuals (mean age 63.6 years, 44% male) from the population-based Rotterdam Study. Diffusion-MRI was used to assess microstructural integrity of the normal-appearing white matter. Mean diffusivity (MD) and fractional anisotropy (FA) were evaluated as markers of white matter integrity. During a follow up time of 5.4 years all-cause mortality was recorded. For cause-specific mortality follow up was available for 3.6 years. Death due to cardiovascular mortality was classified as ICD-10 codes I00-I99 and death due to other reasons was recorded as non-cardiovascular mortality. Cox regression models, adjusted for age, sex, cardiovascular risk factors and macrostructural MRI changes, were used to estimate hazard ratios. Results: White matter in the population had an average MD of 0.7460.03 10-3 mm2/s and average FA of 0.3460.01. Figure 1 shows mortality rates in relation to FA and MD tertiles. Subjects with highest MD and lowest FA measures, reflecting impaired white matter integrity, had highest mortality risk. Each standard deviation lower FA and each standard deviation higher MD were associated with 1.37 fold (95%CI: 1.20, 1.57) and 1.49 fold (95%CI: 1.28, 1.75) higher risk of all-cause mortality, respectively. The associations were more prominent with cardiovascular mortality than non-cardiovascular mortality. Conclusions: Subtle changes in the microstructure of cerebral white matter are independently associated with higher mortality from both cardiovascular and non-cardiovascular causes.
P3-138
P677
SLEEP QUALITY IS ASSOCIATED WITH BRAIN STRUCTURE OF COGNITIVELY NORMAL ADULTS IN MIDDLE AND OLD AGES
Zhuang Song, Ayesha Karnik, Denise C Park, University of Texas at Dallas, Dallas, TX, USA. Contact e-mail: [email protected] Background: Sleep quality is a complex behavior that may play a causal role in Alzheimer’s disease as well as be profoundly affected by both aging and Alzheimer’s disease. In the present study, we hypothesized that poor sleep quality in normal adults would degrade brain structure, affecting regional brain tissue volumes in both middle aged and older adults. Methods: We studied cognitively normal adults in middle age (40-59 y, MMSE¼26-30, N¼25) and old age (60-79 y, MMSE¼26-30, N¼19) from the Dallas Lifespan Brain Study and assessed sleep with the Pittsburgh Sleep Quality Index (PSQI). We first acquired whole brain T1-weighted structural MRI scans using deformation-based morphometry and then acquired sleep quality assessment data (range of 0 to 18 months after scan). We assessed the relationship between the global sleep quality score and regional brain volumes in middle-aged and old adults, treating sleep quality as a continuous variable in a general linear model (false discovery correction, p<0.05). Results: For the middle aged, poor global sleep quality score was significantly related to a volume increase primarily in the cerebrospinal fluid surrounding the left cerebellum and brainstem, and gray matter volume reduction in bilateral caudate nucleus (Figure 1). For the older group, poor sleep quality was related to gray matter reduction in right cerebellum, occipital cortex, medial prefrontal cortex, and left thalamus (Figure 2). In a third analysis, we extracted the significant clusters (two from middle-age and four from old age) and conducted a linear regression, assessing age, sleep quality and the interaction term. Five regions showed a main effect of global sleep quality score (p<0.005), and the left thalamus approached significance (p¼0.08). The interaction was significant for all six clusters, confirming differences in grey matter volumes as a function of age and sleep quality (p<¼0.01). Conclusions: Poor sleep quality was consistently related to gray matter volume reduction in both the middle aged and older groups. The cerebellum was particularly affected as a relevant cluster appeared in both age groups. These data provide early evidence that poor sleep quality is detrimental to brain structure in both middle aged and older adults.
Figure 1. Global sleep quality score is related to regional brain volumes in the middle age group.
Figure 1. Mortality rates and 95% CI per 1000 person-years in tertiles of fractional anisotropy (FA) and mean diffusivity (MD)
Figure 2. Global sleep quality score is related to regional brain volumes in the old age group.
Poster Presentations: P3
(GDS) (p<0.0001), younger age (p¼0.003), and better socioeconomic status (Hollingshead) (p¼0.001) were associated with greater Purpose in Life (R2¼0.29, p<0.0001 for the overall model). The cognitive factor scores were not retained in the model. In the second model, greater FDG metabolism (p¼0.008), younger age (p¼0.03), and better socioeconomic status (p<0.0001) were associated with greater Purpose in Life (R2¼0.12, p<0.0001 for the overall model). Other imaging biomarkers and interactions were not retained in the model. Conclusions: Our findings support a relationship between fewer depressive symptoms and greater Purpose in Life. Moreover, the association of Purpose in Life with greater FDG metabolism, a marker of brain reserve, suggests that Purpose in Life may be an indicator of both better mental health and brain function.
P3-136
spective fMRI study with 66 seniors aged 70 to 80 years; 24 normal weight (with BMI18.50), 26 overweight (with BMI between 18.5 and 29.99), and 15 obese (with BMI 30.00). Participants performed a finger tapping task during fMRI scanning. Clinical measures of executive functions were assessed at baseline and 12 months. Results: After adjusting for baseline performance measure, comorbidity, gender, and age, obese individuals showed decreased task-related connectivity in the default mode network (DMN;
HOW DOES HIGHER BMI PRESERVE COGNITION AMONG OLDER ADULTS? A 12-MONTH EXPLORATORY NEUROIMAGING STUDY
Chun Liang Hsu1,2, Michelle W. Voss3, John R. Best1,4, Todd C. Handy1, Kenneth Madden1, Teresa Liu-Ambrose1,4, 1University of British Columbia, Vancouver, BC, Canada; 2Djavad Mowafaghian Center for Brain Health, Vancouver, BC, Canada; 3University of Iowa, Iowa City, IA, USA; 4Djavad Mowafaghian Centre for Brain Health, Vancouver, BC, Canada. Contact e-mail: [email protected]
Figure 1. Bonferroni-Corrected Task-State Group Contrast Map Highlighted areas show regions where Normal > Obese in DMN functional connectivity (p<0.006) during finger tapping.
Background: Obesity and dementia are both increasing in prevalence worldwide. While obesity are associated with key vascular risk factors (e.g., hypertension, diabetes) for dementia, the relationship between body fat and cognitive function in older adults remain equivocal. In fact, there is evidence body fat may be neural-protective for older adults. Neuroimaging studies of otherwise healthy adults demonstrate that increased body mass index (BMI) is associated with global and regional brain atrophy, as well as altered functional connectivity. However, few studies to date have investigated neural mechanisms of obesity-induced cognitive changes in older adults. In a 12-month prospective study, we aimed to examine: 1) the impact of BMI on functional brain connectivity; and 2) the role of functional brain connectivity in the association between BMI and cognitive function. Methods: A 12-month proTable 1A Partial Correlations of Connectivity and Cognitive Outcome Measures DMN Connectivity During Finger Tapping Variables
Pearson’s r
p-value
Digit Span Test at 12-Month Stroop Test at 12-Month Trail Making Test at 12- Month
0.30 -0.25 -0.16
0.02 0.85 0.25
*Controlled for baseline FCI, baseline mean ABC, baseline age, and baseline gender.
Figure 2. Direct and Indirect Effects of the Proposed Mediation Model
Table 1B Partial Correlations of Baseline BMI, Network Connectivity, and Cognitive Outcome Measures
Baseline BMI
DMN Finger Tapping
Digit Span Test 12-Month
StroopTest 12- Month
Trail Making Test 12-Month
Pearson’s r
p-value
Pearson’s r
p-value
Pearson’s r
p-value
Pearson’s r
p- value
-0.45
0.001
0.013
0.93
-0.06
0.67
0.17
0.22
*Controlled for baseline FCI, baseline mean ABC, baseline age, and baseline gender.
Poster Presentations: P3
p<0.006), which was significantly correlated with Digit Span Test performance (i.e. working memory) at 12 months (p<0.02) and BMI (p<0.001). Conclusions: Supporting evidence that report older individuals with higher BMI had less observable amyloid deposition within the DMN, we found elevated BMI indirectly lead to lower task-state DMN connectivity, which, in turn, lead to better performance on Digit Span Test. This suggests DMN connectivity mediates and suppresses the effect of BMI on cognitive function, and may be involved in compensatory processes in older adults.
P3-137
MICROSTRUCTURAL WHITE MATTER INTEGRITY AND RISK OF MORTALITY
Sanaz Sedaghat, Lotte G. M. Cremers, Marius de Groot, Albert Hofman, Aad van der Lugt, Oscar H. Franco, Abbas Dehghan, M. Arfan Ikram, Meike W. Vernooij, Erasmus MC, Rotterdam, Netherlands. Contact e-mail: [email protected] Background: While several studies reported a link between presence of white matter lesions and shorter survival, it is not yet clear whether this link extends to more subtle cerebral white matter changes. We investigated the independent association of cerebral white matter microstructural integrity with mortality. Methods: We included 4294 stroke and dementia free individuals (mean age 63.6 years, 44% male) from the population-based Rotterdam Study. Diffusion-MRI was used to assess microstructural integrity of the normal-appearing white matter. Mean diffusivity (MD) and fractional anisotropy (FA) were evaluated as markers of white matter integrity. During a follow up time of 5.4 years all-cause mortality was recorded. For cause-specific mortality follow up was available for 3.6 years. Death due to cardiovascular mortality was classified as ICD-10 codes I00-I99 and death due to other reasons was recorded as non-cardiovascular mortality. Cox regression models, adjusted for age, sex, cardiovascular risk factors and macrostructural MRI changes, were used to estimate hazard ratios. Results: White matter in the population had an average MD of 0.7460.03 10-3 mm2/s and average FA of 0.3460.01. Figure 1 shows mortality rates in relation to FA and MD tertiles. Subjects with highest MD and lowest FA measures, reflecting impaired white matter integrity, had highest mortality risk. Each standard deviation lower FA and each standard deviation higher MD were associated with 1.37 fold (95%CI: 1.20, 1.57) and 1.49 fold (95%CI: 1.28, 1.75) higher risk of all-cause mortality, respectively. The associations were more prominent with cardiovascular mortality than non-cardiovascular mortality. Conclusions: Subtle changes in the microstructure of cerebral white matter are independently associated with higher mortality from both cardiovascular and non-cardiovascular causes.
P3-138
P677
SLEEP QUALITY IS ASSOCIATED WITH BRAIN STRUCTURE OF COGNITIVELY NORMAL ADULTS IN MIDDLE AND OLD AGES
Zhuang Song, Ayesha Karnik, Denise C Park, University of Texas at Dallas, Dallas, TX, USA. Contact e-mail: [email protected] Background: Sleep quality is a complex behavior that may play a causal role in Alzheimer’s disease as well as be profoundly affected by both aging and Alzheimer’s disease. In the present study, we hypothesized that poor sleep quality in normal adults would degrade brain structure, affecting regional brain tissue volumes in both middle aged and older adults. Methods: We studied cognitively normal adults in middle age (40-59 y, MMSE¼26-30, N¼25) and old age (60-79 y, MMSE¼26-30, N¼19) from the Dallas Lifespan Brain Study and assessed sleep with the Pittsburgh Sleep Quality Index (PSQI). We first acquired whole brain T1-weighted structural MRI scans using deformation-based morphometry and then acquired sleep quality assessment data (range of 0 to 18 months after scan). We assessed the relationship between the global sleep quality score and regional brain volumes in middle-aged and old adults, treating sleep quality as a continuous variable in a general linear model (false discovery correction, p<0.05). Results: For the middle aged, poor global sleep quality score was significantly related to a volume increase primarily in the cerebrospinal fluid surrounding the left cerebellum and brainstem, and gray matter volume reduction in bilateral caudate nucleus (Figure 1). For the older group, poor sleep quality was related to gray matter reduction in right cerebellum, occipital cortex, medial prefrontal cortex, and left thalamus (Figure 2). In a third analysis, we extracted the significant clusters (two from middle-age and four from old age) and conducted a linear regression, assessing age, sleep quality and the interaction term. Five regions showed a main effect of global sleep quality score (p<0.005), and the left thalamus approached significance (p¼0.08). The interaction was significant for all six clusters, confirming differences in grey matter volumes as a function of age and sleep quality (p<¼0.01). Conclusions: Poor sleep quality was consistently related to gray matter volume reduction in both the middle aged and older groups. The cerebellum was particularly affected as a relevant cluster appeared in both age groups. These data provide early evidence that poor sleep quality is detrimental to brain structure in both middle aged and older adults.
Figure 1. Global sleep quality score is related to regional brain volumes in the middle age group.
Figure 1. Mortality rates and 95% CI per 1000 person-years in tertiles of fractional anisotropy (FA) and mean diffusivity (MD)
Figure 2. Global sleep quality score is related to regional brain volumes in the old age group.