Brain Sci

Mild cognitive impairment (MCI) (amnestic or non-amnestic) has different clinical and neuropsychological characteristics, and its evolution is heterogeneous. Cardiovascular risk factors (CVRF), such as hypertension, diabetes, or dyslipidemia, and the presence of the Apolipoprotein E epsilon4 (ApoE epsilon4) polymorphism have been associated with an increased risk of developing Alzheimer's disease (AD) and other dementias but the relationship is inconsistent worldwide. We aimed to establish the association between the ApoE epsilon4 carrier status and CVRF on MCI subtypes (amnestic and non-amnestic) in Mexican older adults. Cross-sectional study including 137 older adults (n = 63 with normal cognition (NC), n = 24 with amnesic, and n = 50 with non-amnesic MCI). Multinomial logistic regression models were performed in order to determine the association between ApoE epsilon4 polymorphism carrier and CVRF on amnestic and non-amnestic-MCI. ApoE epsilon4 carrier status was present in 28.8% participants. The models showed that ApoE epsilon4 carrier status was not associated neither aMCI nor naMCI condition. The interaction term ApoE epsilon4 x CVRF was not statistically significant for both types of MCI. However, CVRF were associated with both types of MCI and the association remained statistically significant after adjustment by sex, age, and education level. The carrier status of the ApoE genotype does not contribute to this risk

DISPERSED TREES IN PASTURELANDS OF CATTLE FARMS IN A TROPICAL DRY ECOSYSTEM

In many tropical cattle farms of Central America, farmers commonly retain trees in pastures to obtain timber and provide shade and fodder to cattle. However, little is known about the diversity, abundance, richness and species composition of dispersed trees in pastures of cattle farms in the dry tropics. Therefore, the objective of this study was to characterize and describe the pattern of tree cover dispersed in pastures of cattle farm systems assessing their roles in sustaining farm productivity. The study was conducted in 16 cattle farms in a tropical dry ecosystem in Costa Rica. A total of 5,896 trees, from 36 families and 99 species, were found dispersed in pastures (836 ha). Trees were present on 100% of the farms and in 85% of pastures and they occurred as individual trees (54%) and clustered (46%). The most abundant families are Bignonaceae, Sterculeaceae and Boraginaceae. The most common tree species were Tabebuia rosea (Bertol.) DC, Guazuma ulmifolia Lam, Cordia alliodora (Ruiz & Pav.) Oken and Acrocomia aculeata (Jacq.) Lodd. ex Mart, which together accounted for 60% of the total number of trees. Tree species with smaller crowns are found at higher densities than tree species with large crowns. Pastures mean crown cover was 7% (SE + 0.54) and mean tree density was 8.1 trees ha-1 (SE + 0.66). We conclude that farmers are managing a low tree diversity, cover (m2 ha-1) and density (trees ha-1) for fulfilling different farm needs that contribute to farm productivity but minimizing interference with pasture productivity

Association of vitamin d with mild cognitive impairment and alzheimer's dementia in older mexican adults

Background: It has been proposed that Vitamin D helps reduce the accumulation of cerebral beta-amyloid-42 by innate immune stimulation and phagocytosis activation. An association between low Vitamin D levels and Alzheimer's dementia (AD) has been established. We determined the association between Vitamin D, mild cognitive impairment (MCI), and AD in older Mexican adults (> 65 years). Methods: Cross-sectional study conducted at the memory clinic in a tertiary-level hospital in Mexico City. We evaluated subjects with MCI, AD, and normal cognition (NC) with available serum Vitamin D [25(OH)D] levels (past 6 months). Three categories were assigned according to 25(OH)D levels: sufficiency (> 30 ng/mL), insufficiency (21-29 ng/mL), and deficiency (</= 20 ng/mL). Descriptive statistics, means and standard deviations were used. Logistic regression analyses adjusted by age, sex, and educational level were performed. Results: We evaluated 208 patients. Mean age was 79 +/- 1 year, 65% (n = 136) were female; and mean educational level was 6.7 +/- 2.3 years. Thirty-one subjects (14%) had NC; 42% (n = 88) had MCI; and 43% (n = 89) had AD. Prevalence of Vitamin D deficiency was 54%, more frequent in the AD group (64%) followed by the MCI (59%) and NC (13%) (p < 0.001) groups. In the multivariate logistic regression analysis, Vitamin D deficiency was associated with MCI (HR 25.02 [confidence interval 95% 4.48-139]; p < 0.001) and AD (HR 41.7 [5.76-301]; p < 0.001) after adjusting for confounders. Conclusions: Serum Vitamin D deficiency was associated with MCI and dementia; low levels produced a greater effect over executive functions

Factores asociados a la demencia mixta en comparación con demencia tipo Alzheimer en adultos mayores mexicanos

Resumen: Introducción: El concepto de demencia mixta (DMix) se refiere a la demencia por enfermedad de Alzheimer (EA) y la presencia de enfermedad vascular cerebral (EVC). El objetivo del estudio fue identificar los factores clínicos e imagenológicos asociados a la DMix en comparación con la enfermedad de Alzheimer. Material y métodos: Estudio transversal que incluyó a 225 sujetos de 65 años y más, en la clínica de memoria de un hospital de tercer nivel de la Ciudad de México. A todos los pacientes se les realizó una evaluación clínica, neuropsicológica y una imagen cerebral. Se incluyó a pacientes con diagnóstico de DMix y EA. Se realizó un análisis multivariado para determinar factores de asociación a la DMix. Resultados: Se estudió a 137 sujetos con DMix. En comparación con los pacientes con EA, en los pacientes con DMix los factores asociados fueron mayor edad, diabetes, hipertensión y dislipidemia, así como antecedente de EVC, p < 0,05. El análisis multivariado mostró que la hipertensión (OR 1,92, IC: 1,.62-28.82, p < 0,05), la enfermedad de sustancia blanca (OR 3,61, IC: 8,55-159,80, p < 0,05) e infartos lacunares (OR 3,35, IC: 1,97-412,34, p < 0,05) estuvieron asociados a la DMix, mientras que la historia de depresión resuelta tuvo una asociación inversa (OR 0,11, IC: 0,02-0,47, p < 0,05). Conclusiones: La DMix podría ser más frecuente que la EA. Factores de riesgo como la edad avanzada y otros potencialmente modificables se relacionaron con esta forma de demencia. Es necesario conocer y definir a la DMix. Abstract: Introduction: Mixed dementia (DMix) refers to dementia resulting from Alzheimer disease in addition to cerebrovascular disease. The study objectives were to determine the clinical and imaging factors associated with Dmix and compare them to those associated with Alzheimer disease. Material and methods: Cross-sectional study including 225 subjects aged 65 years and over from a memory clinic in a tertiary hospital in Mexico City. All patients underwent clinical, neuropsychological, and brain imaging studies. We included patients diagnosed with DMix or Alzheimer disease (AD). A multivariate analysis was used to determine factors associated with DMix. Results: We studied 137 subjects diagnosed with Dmix. Compared to patients with AD, Dmix patients were older and more likely to present diabetes, hypertension, dyslipidaemia, and history of cerebrovascular disease (P<.05). The multivariate analysis showed that hypertension (OR 1.92, CI 1.62-28.82; P=.009), white matter disease (OR 3.61, CI 8.55-159.80; P<.001), and lacunar infarcts (OR 3.35, CI 1.97-412.34; P=.014) were associated with Dmix, whereas a history of successfully treated depression showed an inverse association (OR 0.11, CI 0.02-0-47; P=.004) Conclusions: DMix may be more frequent than AD. Risk factors such as advanced age and other potentially modifiable factors were associated with this type of dementia. Clinicians should understand and be able to define Dmix. Palabras clave: Demencia mixta, Enfermedad de Alzheimer, Diabetes, Hipertensión, Depresión, Keywords: Mixed dementia, Alzheimer disease, Diabetes, Hypertension, Depressio

Dement Geriatr Cogn Dis Extra

Introduction: Cerebral small-vessel disease (SVD) represents the most frequent type of vascular brain lesions, often coexisting with Alzheimer disease (AD). By quantifying white matter hyperintensities (WMH) and hippocampal and parietal atrophy, we aimed to describe the prevalence and severity of SVD among older adults with normal cognition (NC), mild cognitive impairment (MCI), and probable AD and to describe associated risk factors. Methods: This study included 105 older adults evaluated with magnetic resonance imaging and clinical and neuropsychological tests. We used the Fazekas scale (FS) for quantification of WMH, the Scheltens scale (SS) for hippocampal atrophy, and the Koedam scale (KS) for parietal atrophy. Logistic regression models were performed to determine the association between FS, SS, and KS scores and the presence of NC, MCI, or probable AD. Results: Compared to NC subjects, SVD was more prevalent in MCI and probable AD subjects. After adjusting for confounding factors, logistic regression showed a positive association between higher scores on the FS and probable AD (OR = 7.6, 95% CI 2.7-20, p < 0.001). With the use of the SS and KS (OR = 4.5, 95% CI 3.5-58, p = 0.003 and OR = 8.9, 95% CI 1-72, p = 0.04, respectively), the risk also remained significant for probable AD. Conclusions: These results suggest an association between severity of vascular brain lesions and neurodegeneration

BMC Geriatr

Background Cognitive impairment is twice more frequent in elderly with type 2 diabetes mellitus (DM). This study was conducted to determine the association between glycemic control and cognitive performance among community-dwelling elderly persons in Mexico. Methods Cross-sectional study conducted in individuals aged 60 years or elderly participating in the 2012 Mexican Health and Aging Study. Type 2 DM participants were classified in 3 groups according to their glycated hemoglobin levels (HbA1c): < 7% (intensive control), 7–7.9% (standard control) or ≥ 8% (poor control), and cognitive performance: low (CCCE ≤44 points), intermediate (44.1–59.52 points), or high (≥59.53 points). Multinomial logistic regression models were constructed to determine this association. Results Two hundred sixteen community-dwelling adults aged 60 and older with type 2 diabetes were selected. Subjects in the low cognitive performance group were older (69.7 ± 6.6 vs 65.86 ± 5.18 years, p < .001) and had a lower educational level (2.5 ± 2.6 vs 7.44 ± 4.15 years, p < .000) when compared to the high cognitive performance participants. HbA1c ≥ 8% was associated with having low (Odds Ratio (OR) 3.17, 95% CI 1.17–8.60, p = .024), and intermediate (OR 3.23, 95% CI 1.27–8.20, p = .014) cognitive performance; this trend was not found for HbA1c 7.0–7.9% group. The multinomial regression analysis showed that the presence of HbA1c ≥ 8% (poor glycemic control) was associated with low (OR 3.17, 95% CI = 1.17–8.60, p = .024), and intermediate (OR 3.23, 95% CI = 1.27–8.20, p = .014) cognitive performance. After adjusting for confounding variables. Conclusions Glycemic control with a HbA1c ≥ 8% was associated with worse cognitive performance

Cerebral Vascular Reactivity in Frail Older Adults with Vascular Cognitive Impairment

Background: Frailty, a state of increased vulnerability, could play a role in the progression of vascular dementia. We aim to describe the changes in cerebrovascular reactivity of older adults with frailty and vascular-type mild cognitive impairment (MCIv). Methods: This was a cross-sectional study. A comprehensive geriatric assessment, neuropsychological evaluation, and transcranial Doppler ultrasound (TCD) was performed on 180 participants who were allocated into four groups: healthy (n = 74), frail (n = 40), MCIv (n = 35), and mixed (frail + MCIv) (n = 31). ANOVA and Kruskal&ndash;Wallis tests were used for the analysis of continuous variables with and without normal distribution. Multinomial logistic regression was constructed to identify associated covariates. Results: Subjects in the mixed group, compared to healthy group, were older (75.0 &plusmn; 5.9 vs 70.3 &plusmn; 5.9 years; p &lt; 0.001), showed lower education (9.3 &plusmn; 6.4 vs 12.2 &plusmn; 4.0 years; p = 0.054), greater frequency of diabetes (42% vs 12%; p = 0.005), worse cognitive performance (z = &minus;0.81 &plusmn; 0.94), and reduced left medial-cerebral artery cerebrovascular reactivity (0.43 &plusmn; 0.42 cm/s). The mixed group was associated with age (odds ratio (OR) 1.16, 95% Confidence Interval (CI) = 1.06&ndash;1.27; p &lt; 0.001), diabetes (OR 6.28, 1.81&ndash;21.84; p = 0.004), and Geriatric Depression Scale (GDS) score (OR 1.34, 95% CI = 1.09&ndash;1.67; p = 0.007). Conclusions: Frailty among older adults was associated with worse cognitive performance, diabetes, and decreased cerebral blood flow