@article {8831, title = {Longitudinal Plasma Measures of Trimethylamine N-Oxide and Risk of Atherosclerotic Cardiovascular Disease Events in Community-Based Older Adults.}, journal = {J Am Heart Assoc}, year = {2021}, month = {2021 Aug 16}, pages = {e020646}, abstract = {

Background Trimethylamine N-oxide (TMAO) is a gut microbiota-dependent metabolite of dietary choline, L-carnitine, and phosphatidylcholine-rich foods. On the basis of experimental studies and patients with prevalent disease, elevated plasma TMAO may increase risk of atherosclerotic cardiovascular disease (ASCVD). TMAO is also renally cleared and may interact with and causally contribute to renal dysfunction. Yet, how serial TMAO levels relate to incident and recurrent ASCVD in community-based populations and the potential mediating or modifying role of renal function are not established. Methods and Results We investigated associations of serial measures of plasma TMAO, assessed at baseline and 7~years, with incident and recurrent ASCVD in a community-based cohort of 4131 (incident) and 1449 (recurrent) older US adults. TMAO was measured using stable isotope dilution liquid chromatography-tandem mass spectrometry (laboratory coefficient of variation, <6\%). Incident ASCVD (myocardial infarction, fatal coronary heart disease, stroke, sudden cardiac death, or other atherosclerotic death) was centrally adjudicated using medical records. Risk was assessed by multivariable Cox proportional hazards regression, including time-varying demographics, lifestyle factors, medical history, laboratory measures, and dietary habits. Potential mediating effects and interaction by estimated glomerular filtration rate (eGFR) were assessed. During prospective follow-up, 1766 incident and 897 recurrent ASCVD events occurred. After multivariable adjustment, higher levels of TMAO were associated with a higher risk of incident ASCVD, with extreme quintile hazard ratio (HR) compared with the lowest quintile=1.21 (95\% CI, 1.02-1.42; -trend=0.029). This relationship appeared mediated or confounded by eGFR (eGFR-adjusted HR, 1.07; 95\% CI, 0.90-1.27), as well as modified by eGFR (-interaction <0.001). High levels of TMAO were associated with higher incidence of ASCVD in the presence of impaired renal function (eGFR <60~mL/min per 1.73~m: HR, 1.56 [95\% CI, 1.13-2.14]; -trend=0.007), but not normal or mildly reduced renal function (eGFR >=60~mL/min per 1.73~m: HR, 1.03 [95\% CI, 0.85-1.25]; -trend=0.668). Among individuals with prior ASCVD, TMAO associated with higher risk of recurrent ASCVD (HR, 1.25 [95\% CI, 1.01-1.56]; -trend=0.009), without significant modification by eGFR. Conclusions In this large community-based cohort of older US adults, serial measures of TMAO were associated with higher risk of incident ASCVD, with apparent modification by presence of impaired renal function and with higher risk of recurrent ASCVD.

}, issn = {2047-9980}, doi = {10.1161/JAHA.120.020646}, author = {Lee, Yujin and Nemet, Ina and Wang, Zeneng and Lai, Heidi T M and de Oliveira Otto, Marcia C and Lemaitre, Rozenn N and Fretts, Amanda M and Sotoodehnia, Nona and Budoff, Matthew and DiDonato, Joseph A and McKnight, Barbara and Tang, W H Wilson and Psaty, Bruce M and Siscovick, David S and Hazen, Stanley L and Mozaffarian, Dariush} } @article {9157, title = {Longitudinal Associations of Plasma TMAO and Related Metabolites with Cognitive Impairment and Dementia in Older Adults: The Cardiovascular Health Study.}, journal = {J Alzheimers Dis}, year = {2022}, month = {2022 Sep 02}, abstract = {

BACKGROUND: Animal studies suggest that gut microbiome metabolites such as trimethylamine N-oxide (TMAO) may influence cognitive function and dementia risk. However potential health effects of TMAO and related metabolites remain unclear.

OBJECTIVE: We examined prospective associations of TMAO, γ-butyrobetaine, crotonobetaine, carnitine, choline, and betaine with risk of cognitive impairment and dementia among older adults aged 65 years and older in the Cardiovascular Health Study (CHS).

METHODS: TMAO and metabolites were measured in stored plasma specimens collected at baseline. Incident cognitive impairment was assessed using the 100-point Modified Mini-Mental State Examination administered serially up to 7 times. Clinical dementia was identified using neuropsychological tests adjudicated by CHS Cognition Study investigators, and by ICD-9 codes from linked Medicare data. Associations of each metabolite with cognitive outcomes were assessed using Cox proportional hazards models.

RESULTS: Over a median of 13 years of follow-up, 529 cases of cognitive impairment, and 522 of dementia were identified. After multivariable adjustment for relevant risk factors, no associations were seen with TMAO, carnitine, choline, or betaine. In contrast, higher crotonobetaine was associated with 20-32\% higher risk of cognitive impairment and dementia per interquintile range (IQR), while γ-butyrobetaine was associated with \~{}25\% lower risk of the same cognitive outcomes per IQR.||Conclusion:These findings suggest that γ-butyrobetaine, crotonobetaine, two gut microbe and host metabolites, are associated with risk of cognitive impairment and dementia. Our results indicate a need for mechanistic studies evaluating potential effects of these metabolites, and their interconversion on brain health, especially later in life.

}, issn = {1875-8908}, doi = {10.3233/JAD-220477}, author = {de Oliveira Otto, Marcia C and Li, Xinmin S and Wang, Zeneng and Siscovick, David and Newman, Anne B and Lai, Heidi Tsz Mung and Nemet, Ina and Lee, Yujin and Wang, Meng and Fretts, Amanda and Lemaitre, Rozenn N and Tang, W H Wilson and Lopez, Oscar and Hazen, Stanley L and Mozaffarian, Dariush} }