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- Hooshmand, Babak, et al.
(författare)
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Association of Methionine to Homocysteine Status With Brain Magnetic Resonance Imaging Measures and Risk of Dementia
- 2019
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Ingår i: JAMA psychiatry. - : American Medical Association (AMA). - 2168-6238 .- 2168-622X. ; 76:11, s. 1198-1205
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Tidskriftsartikel (refereegranskat)abstract
- IMPORTANCE Impairment of methylation status (ie, methionine to homocysteine ratio) may be a modifiable risk factor for structural brain changes and incident dementia.OBJECTIVE To investigate the association of serum markers of methylation status and sulfur amino acids with risk of incident dementia, Alzheimer disease (AD), and the rate of total brain tissue volume loss during 6 years.DESIGN, SETTING, AND PARTICIPANTS This population-based longitudinal study was performed from March 21, 2001, to October 10, 2010, in a sample of 2570 individuals aged 60 to 102 years from the Swedish Study on Aging and Care in Kungsholmen who were dementia free at baseline and underwent comprehensive examinations and structural brain magnetic resonance imaging (MRI) on 2 to 3 occasions during 6 years. Data analysis was performed from March 1, 2018, to October 1, 2018.MAIN OUTCOMES AND MEASURES Incident dementia, AD, and the rate of total brain volume loss.RESULTS This study included 2570 individuals (mean [SD] age, 73.1 [10.4] years; 1331 [56.5%] female). The methionine to homocysteine ratio was higher in individuals who consumed vitamin supplements (median, 1.9; interquartile range [IQR], 1.5-2.6) compared with those who did not (median, 1.8; IQR, 1.3-2.3; P<.001) and increased per each quartile increase of vitamin B-12 or folate. In the multiadjusted model, an elevated baseline serum total homocysteine level was associated with an increased risk of dementia and AD during 6 years: for the highest homocysteine quartile compared with the lowest, the hazard ratios (HRs) were 1.60 (95% CI, 1.01-2.55) for dementia and 2.33 (95% CI, 1.26-4.30) for AD. In contrast, elevated concentrations of methionine were associated with a decreased risk of dementia (HR, 0.54; 95% CI, 0.36-0.81) for the highest quartile compared with the lowest. Higher values of the methionine to homocysteine ratio were significantly associated with lower risk of dementia and AD: for the fourth methionine-homocysteine quartile compared with the first quartile, the HR was 0.44 (95% CI, 0.27-0.71) for incident dementia and 0.43 (95% CI, 0.23-0.80) for AD. In the multiadjusted linear mixed models, a higher methionine to homocysteine ratio was associated with a decreased rate of total brain tissue volume loss during the study period (beta [SE] per 1-SD increase, 0.038 [0.014]; P=.007).CONCLUSIONS AND RELEVANCE The methionine to homocysteine status was associated with dementia development and structural brain changes during the 6-year study period, suggesting that a higher methionine to homocysteine ratio may be important in reducing the rate of brain atrophy and decreasing the risk of dementia in older adults.
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| 2. |
- Hooshmand, Babak, et al.
(författare)
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Association of Vitamin B-12, Folate, and Sulfur Amino Acids With Brain Magnetic Resonance Imaging Measures in Older Adults A Longitudinal Population-Based Study
- 2016
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Ingår i: JAMA psychiatry. - : American Medical Association (AMA). - 2168-6238 .- 2168-622X. ; 73:6, s. 606-613
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Tidskriftsartikel (refereegranskat)abstract
- IMPORTANCE Vitamin B-12, folate, and sulfur amino acids may be modifiable risk factors for structural brain changes that precede clinical dementia. OBJECTIVE To investigate the association of circulating levels of vitamin B-12, red blood cell folate, and sulfur amino acids with the rate of total brain volume loss and the change in white matter hyperintensity volume as measured by fluid-attenuated inversion recovery in older adults. DESIGN, SETTING, AND PARTICIPANTS The magnetic resonance imaging subsample of the Swedish National Study on Aging and Care in Kungsholmen, a population-based longitudinal study in Stockholm, Sweden, was conducted in 501 participants aged 60 years or older who were free of dementia at baseline. A total of 299 participants underwent repeated structural brain magnetic resonance imaging scans from September 17, 2001, to December 17, 2009. MAIN OUTCOMES AND MEASURES The rate of brain tissue volume loss and the progression of total white matter hyperintensity volume. RESULTS In the multi-adjusted linear mixed models, among 501 participants (300 women [59.9%]; mean [SD] age, 70.9 [9.1] years), higher baseline vitamin B-12 and holotranscobalamin levels were associated with a decreased rate of total brain volume loss during the study period: for each increase of 1 SD, beta (SE) was 0.048 (0.013) for vitamin B-12 (P < .001) and 0.040 (0.013) for holotranscobalamin (P = .002). Increased total homocysteine levels were associated with faster rates of total brain volume loss in the whole sample (beta [SE] per 1-SD increase, -0.035 [0.015]; P = .02) and with the progression of white matter hyperintensity among participants with systolic blood pressure greater than 140mmHg (beta [SE] per 1-SD increase, 0.000019 [0.00001]; P = .047). No longitudinal associations were found for red blood cell folate and other sulfur amino acids. CONCLUSIONS AND RELEVANCE This study suggests that both vitamin B-12 and total homocysteine concentrations may be related to accelerated aging of the brain. Randomized clinical trials are needed to determine the importance of vitamin B-12 supplementation on slowing brain aging in older adults.
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