Apolipoprotein E genotypes and longevity across dementia disorders

INTRODUCTION: The ε4 allele of the apolipoprotein E (APOE) gene is a prominent risk factor for Alzheimer's disease (AD), but its implication in other dementias is less well studied. METHODS: We used a data set on 2858 subjects (1098 AD, 260 vascular dementia [VaD], 145 mixed AD and VaD, 90 other dementia diagnoses, and 1265 controls) to examine the association of APOE polymorphisms with clinical dementia diagnoses, biomarker profiles, and longevity. RESULTS: The ε4 allele was associated with reduced longevity as ε4 versus ε3 homozygotes lived on average 2.6 years shorter (P = .006). In AD, ε4 carriers lived 1.0 years shorter than noncarriers (P = .028). The ε4 allele was more prevalent in AD, mixed AD and VaD, and VaD patients compared to controls, but not in other dementia disorders. DISCUSSION: The APOE ε4 allele is influential in AD but might also be of importance in VaD and in mixed AD and VaD, diseases in which concomitant AD pathology is common

Homocysteine Levels in Chronic Gastritis and Other Conditions: Relations to Incident Cardiovascular Disease and Dementia

Background Homocysteine levels in circulation are determined by several factors and hyperhomocysteinemia is reportedly associated with cardiovascular diseases and dementia. The aim of this study is to determine the relation of chronic gastritis and other conditions to homocysteine levels and their relation to incident cardiovascular diseases and dementia. Methods An adult population-based cohort (N = 488) was screened for H. pylori infection, gastro-duodenitis (endoscopic biopsies), disease history, and lifestyle factors. Blood samples were analyzed for pepsinogen I and II (gastric function), vitamin B12, folate, homocysteine, and cystatin C (renal function). The methylenetetrahydrofolate reductase C677T polymorphism reportedly associated with hyperhomocysteinemia was analyzed by pyrosequencing. Incident cardiovascular diseases and dementia were monitored during a median follow-up interval of 10 years. Results At baseline, there was a positive relation of S-homocysteine to male gender, age, S-cystatin C, methylenetetrahydrofolate reductase 677TT genotype and atrophic gastritis. During follow-up, cardiovascular diseases occurred in 101/438 and dementia in 25/488 participants, respectively. Logistic regression analysis (adjusting for gender, age at baseline, follow-up interval, BMI, smoking, alcohol consumption, NSAID use, P-cholesterol, and P-triglycerides) showed an association of S-homocysteine higher than 14.5 μmol/l to cardiovascular diseases (OR 2.05 [95% c.i. 1.14–3.70]), but not to dementia overall. Conclusions Gender, age, vitamin B12, folate, renal function, atrophic gastritis and the methylenetetrahydrofolate 677TT genotype were significant determinants of homocysteine levels, which were positively related to incident cardiovascular diseases

Biomarkers of microvascular endothelial dysfunction predict incident dementia : a population-based prospective study

BACKGROUND: Cerebral endothelial dysfunction occurs in a spectrum of neurodegenerative diseases. Whether biomarkers of microvascular endothelial dysfunction can predict dementia is largely unknown. We explored the longitudinal association of midregional pro-atrial natriuretic peptide (MR-proANP), C-terminal endothelin-1 (CT-proET-1) and midregional proadrenomedullin (MR-proADM) with dementia and subtypes amongst community-dwelling older adults.METHODS: A population-based cohort of 5347 individuals (men, 70%; age, 69 ± 6 years) without prevalent dementia provided plasma for determination of MR-proANP, CT-proET-1 and MR-proADM. Three-hundred-and-seventy-three patients (7%) were diagnosed with dementia (120 Alzheimer's disease, 83 vascular, 102 mixed, and 68 other aetiology) over a period of 4.6 ± 1.3 years. Relations between baseline biomarker plasma concentrations and incident dementia were assessed using multivariable Cox regression analysis.RESULTS: Higher levels of MR-proANP were significantly associated with increased risk of all-cause and vascular dementia (hazard ratio [HR] per 1 SD: 1.20, 95% confidence interval [CI], 1.07-1.36; P = 0.002, and 1.52; 1.21-1.89; P < 0.001, respectively). Risk of all-cause dementia increased across the quartiles of MR-proANP (p for linear trend = 0.004; Q4, 145-1681 pmol L(-1) vs. Q1, 22-77 pmol L(-1) : HR: 1.83; 95%CI: 1.23-2.71) and was most pronounced for vascular type (p for linear trend = 0.005: HR: 2.71; 95%CI: 1.14-6.46). Moreover, the two highest quartiles of CT-proET-1 predicted vascular dementia with a cut-off value at 68 pmol L(-1) (Q3-Q4, 68-432 pmol L(-1) vs. Q1-Q2,4-68 pmol L(-1) ; HR: 1.94; 95%CI: 1.12-3.36). Elevated levels of MR-proADM indicated no increased risk of developing dementia after adjustment for traditional risk factors.CONCLUSIONS: Elevated plasma concentration of MR-proANP is an independent predictor of all-cause and vascular dementia. Pronounced increase in CT-proET-1 indicates higher risk of vascular dementia

High circulating levels of midregional proenkephalin A predict vascular dementia : a population-based prospective study

Midregional Pro-enkephalin A (MR-PENK A) and N-terminal Protachykinin A (NT-PTA) have been associated with vascular dementia. However, the longitudinal relationship between these biomarkers and incident dementia has not been fully investigated. In the population-based Malmö Preventive Project, circulating levels of MR-PENK A and NT-PTA were determined in a random sample of 5,323 study participants (mean age: 69 ± 6 years) who were followed-up over a period of 4.6 ± 1.6 years. The study sample included 369 patients (7%) who were diagnosed in the same period with dementia. We analyzed relationship of MR-PENK A and NT-PTA with the risk of developing dementia by using multivariable-adjusted Cox regression models adjusted for traditional risk factors. Increased plasma levels of MR-PENK A were associated with higher risk of incident vascular dementia whereas no associations were found with all-cause or Alzheimer dementia. The risk of vascular dementia was mainly conferred by the highest quartile of MR-PENK as compared with lower quartiles. Elevated levels of NT-PTA yielded significant association with all-cause dementia or dementia subtypes. Elevated plasma concentration of MR-PENK A independently predicts vascular dementia in the general population. MR-PENK A may be used as an additional tool for identifying vascular subtype in ambiguous dementia cases