Cardiac biomarkers are associated with increased risks of adverse clinical outcomes after ischemic stroke.

BACKGROUND: Impaired cardiac function was suggested to be implicated in the functional recovery after ischemic stroke, but the prognostic value of cardiac biomarkers among ischemic stroke patients remains unclear. We aimed to prospectively explore the associations of serum lactate dehydrogenase (LDH), plasma N-terminal pro-brain natriuretic peptide (NT-proBNP), and plasma high-sensitivity cardiac troponin T (hs-cTnT) with adverse clinical outcomes after ischemic stroke in a large-scale cohort study. METHODS: We measured serum LDH, plasma NT-proBNP, and plasma hs-cTnT levels at baseline among 5056 ischemic stroke patients from the Minhang Stroke Cohort study. All patients were followed up at 3 months after ischemic stroke onset. The primary outcome was composite outcome of death and major disability (modified Rankin Scale [mRS] score ≥ 3) at 3 months after stroke onset, and secondary outcomes included death and ordered 7-level categorical score of the mRS. RESULTS: During 3 months of follow-up, 1584 patients developed the primary outcome. Baseline serum LDH, plasma NT-proBNP, and plasma hs-cTnT were positively associated with the risk of adverse outcomes after ischemic stroke. The multivariable-adjusted odds ratios of primary outcome for the highest versus lowest quartile of LDH, NT-proBNP, and hs-cTnT were 1.37 (95% CI 1.13-1.66; Ptrend = 0.001), 2.51 (95% CI, 2.00-3.16; Ptrend < 0.001), and 2.24 (95% CI 1.77-2.83; Ptrend < 0.001), respectively. Each SD increase of log-transformed cardiac biomarker score was associated with a 49% (95% CI 37-62%; P < 0.001) increased risk of primary outcome. Multivariable-adjusted spline regression analyses showed linear relationships between cardiac biomarkers and the risk of primary outcome (all P for linearity < 0.001). Moreover, adding LDH, NT-proBNP, hs-cTnT, or cardiac biomarker score to conventional risk factors significantly improved the risk reclassification of primary outcome after ischemic stroke (all P < 0.05). CONCLUSION: High LDH, NT-proBNP, hs-cTnT, and cardiac biomarker score were independently associated with increased risks of adverse clinical outcomes among ischemic stroke patients, suggesting that cardiac biomarkers might be potential prognostic biomarkers for ischemic stroke.

Association of Crohn's disease and ulcerative colitis with the risk of neurological diseases: a large-scale Mendelian randomization study.

Observational studies suggested increased risks of Alzheimer's disease (AD), Parkinson's disease (PD), and multiple sclerosis (MS) in patients with Crohn's disease (CD) and ulcerative colitis (UC). We aimed to assess the causality for the associations of CD and UC with the risks of AD, PD, and MS through a two-sample Mendelian randomization (MR) study. Independent single nucleotide polymorphisms associated with CD (17,897 cases and 33,977 controls) and UC (13,768 cases and 33,977 controls) were identified as genetic instruments based on a European-descent genome-wide association study (GWAS) released by the International Inflammatory Bowel Disease Genetics Consortium. Summary statistics for AD (combined: 25,881 cases and 256,837 controls), PD (combined: 35,836 cases and 665,686 controls), and MS (combined: 48,477 cases and 285,515 controls) were obtained from the largest GWASs and FinnGen study of European ancestry, respectively. MR estimates were generated using the inverse-variance weighted method in the main analysis with a series of sensitivity analyses. MR analyses were conducted per outcome database and were subsequently meta-analyzed to generate combined estimates. Genetically predicted UC was significantly associated with increased risks of AD (combined: OR, 1.03; 95% CI, 1.01-1.05; P = 1.80 × 10-3) and MS (combined: OR, 1.37; 95% CI, 1.23-1.53; P = 1.18 × 10-8), while there was no association between genetically predicted UC and the risk of PD. In contrast, no significant associations were observed for genetically predicted CD with AD, PD, and MS. MR-Egger regression showed no directional pleiotropy for the identified associations, and sensitivity analyses with different MR methods further confirmed these findings. This study suggested significant adverse effects of UC on AD and MS, highlighting that UC patients should receive early intervention with optimal adjunctive medical therapy to reduce the risks of AD and MS.

Associations between brain imaging-derived phenotypes and cognitive functions.

We aimed to evaluate the potential causal relationship between brain imaging-derived phenotypes and cognitive functions via Mendelian randomization analyses. Genetic instruments for 470 brain imaging-derived phenotypes were selected from a genome-wide association study based on the UK Biobank (n = 33,224). Statistics for cognitive functions were obtained from the genome-wide association study based on the UK Biobank. We used the inverse variance weighted Mendelian randomization method to investigate the associations between brain imaging-derived phenotypes and cognitive functions, and reverse Mendelian randomization analyses were performed for significant brain imaging-derived phenotypes to examine the reverse causation for the identified associations. We identified three brain imaging-derived phenotypes to be associated with verbal-numerical reasoning, including cortical surface area of the left fusiform gyrus (beta, 0.18 [95% confidence interval, 0.11 to 0.25], P = 4.74 × 10-7), cortical surface area of the right superior temporal gyrus (beta, 0.25 [95% confidence interval, 0.15 to 0.35], P = 6.30 × 10-7), and orientation dispersion in the left superior longitudinal fasciculus (beta, 0.14 [95% confidence interval, 0.09 to 0.20], P = 8.37 × 10-7). The reverse Mendelian randomization analysis indicated that verbal-numerical reasoning had no effect on these three brain imaging-derived phenotypes. This Mendelian randomization study identified cortical surface area of the left fusiform gyrus, cortical surface area of the right superior temporal gyrus, and orientation dispersion in the left superior longitudinal fasciculus as predictors of verbal-numerical reasoning.

Plasma Polyamines and Short-Term Adverse Outcomes Among Patients With Ischemic Stroke: A Prospective Cohort Study.

BACKGROUND: Polyamines have been reported to be associated with neurological function, but the associations between polyamines and the prognosis of ischemic stroke remain unclear. We aimed to prospectively investigate whether elevated plasma polyamine levels are associated with adverse outcomes in patients with ischemic stroke. METHODS AND RESULTS: Plasma polyamine levels were measured at admission in 3570 patients with acute ischemic stroke, and clinical outcomes were assessed at 3 months after stroke onset. The primary outcome was a composite outcome of death and major disability (modified Rankin Scale score≥3), and secondary outcomes included the individual outcomes of death and major disability. During a 3-month follow-up period, 877 participants (25.1%) experienced the primary outcome. Increased putrescines were associated with a decreased risk of the primary outcome (the highest versus the lowest tertile: odds ratio, 0.72 [95% CI, 0.58-0.91]; P=0.005) and major disability (odds ratio, 0.59 [95% CI, 0.47-0.74]; P<0.001). Conversely, increased spermidines were associated with an increased risk of death (hazard ratio, 1.86 [95% CI, 1.10-3.14]; P=0.020), and increased spermines were associated with an increased risk of the primary outcome (odds ratio, 1.36 [95% CI, 1.08-1.71]; P=0.009) and major disability (odds ratio, 1.27 [95% CI, 1.01-1.59]; P=0.041). CONCLUSIONS: Among patients with ischemic stroke, high plasma putrescine levels were associated with a decreased risk of adverse outcomes, whereas high plasma spermidine and spermine levels were associated with an increased risk of adverse outcomes. Further studies are needed to investigate whether targeting these polyamines can improve the prognosis of patients with ischemic stroke. REGISTRATION: https://clinicaltrials.gov. Identifier: NCT01840072.

The association of early life factors with depression and anxiety in adults aged 40-69 years: a population-based cohort study.

This study was aimed to explore the longitudinal association of five early life factors (breastfeeding, maternal smoking around birth, birth weight, being born in a multiple birth, and adoption) during the in-utero, perinatal, and early childhood development stages with incidence of depression and anxiety in adults aged 40-69 years. We used data from the UK biobank, 5,02,394 participants aged 40-69 years were recruited between 2006 and 2010. Participants provided information on early life exposures through touchscreen questionnaires or verbal interviews at baseline. The primary outcomes, depression, and anxiety, were defined according to the International Classification of Diseases, 10th Revision. Hazard ratios (HR) and 95% confidence intervals (CI) for each factor were reported. During a median follow-up of 13.6 years, 16,502 (3.55%) participants developed depression, and 15,507 (3.33%) developed anxiety. After adjusting for potential confounders, increased risk of depression was found to be significantly associated with non-breastfeeding (HR, 1.08; 95% CI, 1.04-1.13), maternal smoking around birth (HR, 1.19; 95% CI, 1.14-1.23), being born in multiple births (HR, 1.16; 95% CI, 1.05-1.27), low birth weight (HR, 1.14; 95% CI, 1.07-1.22), and being an adoptee (HR, 1.42; 95% CI, 1.28-1.58). Increased risk of anxiety was associated with non-breastfeeding (HR, 1.09; 95% CI, 1.04-1.13), maternal smoking around birth (HR, 1.11; 95% CI, 1.07-1.16), being born in a multiple births (HR, 1.05; 95% CI, 0.95-1.17), low birth weight (HR, 1.12; 95% CI, 1.05-1.20), and being an adoptee (HR, 1.25; 95% CI, 1.10-1.41). Each of these five early life factors can be considered as early life risk factors for incident depression and anxiety in adulthood independently. The dose-response relationship was also observed, suggesting that with an increase in the number of early life risk factors, the likelihood of experiencing depression and anxiety also increased. These findings highlighted the imperative consideration of early life factors in comprehending the susceptibility to mental health disorders later in life, including non-breastfeeding, maternal smoking around birth, being born in multiple births, low birth weight, and being an adoptee.

Associations of computer gaming with incident dementia, cognitive functions, and brain structure: a prospective cohort study and Mendelian randomization analysis.

BACKGROUND: Computer gaming has recently been suggested to be associated with benefits for cognition, but its impact on incident dementia remains uncertain. We aimed to investigate the observational associations of playing computer games with incident dementia, cognitive functions, and brain structural measures, and further explore the genetic associations between computer gaming and dementia. METHODS: We included 471,346 White British participants without dementia at baseline based on the UK Biobank, and followed them until November 2022. We estimated the risk of dementia using Cox proportional hazard models, and assessed the changes of cognitive functions and brain structural measures using logistic regression models and linear regression models. Mendelian randomization (MR) analyses were performed to examine the association between genetically determined computer gaming and dementia. RESULTS: High frequency of playing computer games was associated with decreased risk of incident dementia (HR, 0.81 [95% CI: 0.69, 0.94]). Individuals with high frequency of playing computer games had better performance in prospective memory (OR, 1.46 [1.26, 1.70]), reaction time (beta, -0.195 [-0.243, -0.147]), fluid intelligence (0.334 [0.286, 0.382]), numeric memory (0.107 [0.047, 0.166]), incorrect pairs matching (-0.253 [-0.302, -0.203]), and high volume of gray matter in hippocampus (0.078 [0.023, 0.134]). Genetically determined high frequency of playing computer games was associated with a low risk of dementia (OR, 0.37 [0.15, 0.91]). CONCLUSIONS: Computer gaming was associated with a decreased risk of dementia, favorable cognitive function, and better brain structure, suggesting that computer gaming could modulate cognitive function and may be a promising target for dementia prevention.

Alcohol drinking modified the effect of plasma YKL-40 levels on stroke-specific mortality of acute ischemic stroke.

OBJECTIVES: Our study aimed to evaluate the association between plasma human cartilage glycoprotein-39 (YKL-40) and stroke-specific mortality at two years in acute ischemic stroke patients according to the drinking status and amount of alcohol consumption. We further investigated the effect of the interaction between these conditions and YKL-40 levels on the outcome. METHODS: We measured plasma YKL-40 levels in 3267 participants from the China Antihypertensive Trial in Acute Ischemic Stroke. Outcome data on stroke-specific mortality were collected at two years after stroke onset. RESULTS: During the two years of follow-up, 208 (6.4 %) patients, including 44 drinkers and 164 nondrinkers, died of stroke-specific causes. The patients in the highest quartile of YKL-40 had a 3.52-fold (95 % CI: 1.15-10.76, P for trend = 0.006) risk of stroke-specific mortality compared with those in the lowest quartile among drinkers. However, no significant association between YKL-40 and the outcome was observed among nondrinkers (HR: 1.18, 95 % CI: 0.75-1.86, P for trend = 0.08). Alcohol drinking modified the effect of YKL-40 on the outcome (P for interaction = 0.04). Subgroup analyses revealed that each 1-unit increase in log-transformed YKL-40 was associated with a 72 % greater risk of stroke-specific mortality for light drinkers. This association was amplified with a 226 % increased risk of the outcome among heavy drinkers. CONCLUSIONS: Elevated YKL-40 levels were associated with an increased risk of stroke-specific mortality at two years among drinkers with ischemic stroke. Drinking status substantially modified the effect of plasma YKL-40 levels on the outcome. This effect was amplified with the increased amount of alcohol consumption. REGISTRATION: URL: https://www. CLINICALTRIALS: gov; Unique identifier: NCT01840072.

Serum brain derived neurotrophic factor levels and post-stroke depression in ischemic stroke patients.

BACKGROUND: Brain-derived neurotrophic factor (BDNF) is crucial for neuronal survival and may be implicated in the pathophysiological process of depression. This study aimed to prospectively investigate the association between serum BDNF and post-stroke depression (PSD) at 3 months in a multicenter cohort study. METHODS: A total of 611 ischemic stroke patients with serum BDNF measurements from the China Antihypertensive Trial in Acute Ischemic Stroke were included in this analysis. We used the 24-item Hamilton Depression Rating Scale to assess depression status at 3 months after ischemic stroke, and PSD was defined as a score of ≥8. RESULTS: Baseline serum BDNF was inversely associated with the risk of depression after ischemic stroke. The multivariable-adjusted odds ratio of PSD for the highest tertile of BDNF was 0.53 (95 % confidence interval, 0.34-0.82; P for trend = 0.004) compared with the lowest tertile. Multivariable-adjusted spline regression model also showed a linear does-response association between serum BDNF levels and PSD at 3 months (P for linearity = 0.006). In addition, adding serum BDNF to conventional risk factors significantly improved the risk reclassification of PSD (net reclassification improvement: 16.98 %, P = 0.039; integrated discrimination index: 0.93 %, P = 0.026). LIMITATIONS: All patients in this study were Chinese, so our findings should be applied to other populations cautiously. CONCLUSIONS: Higher serum BDNF levels at baseline were significantly associated with a decreased risk of PSD at 3 months, suggesting that BDNF might be a valuable predictive biomarker and potential therapeutic target for PSD among ischemic stroke patients.

Lower plasma linoleic acids as a risk factor for gout: an integrated analysis of population-based cohort and genetic data.

Background: Gout is a nutrition-related, highly prevalent inflammatory arthritis with undesirable effects on the quality of life. The relationships between circulating fatty acids (FAs) and gout remain poorly understood. Method: We included 268 174 participants with plasma FAs measured using nuclear magnetic resonance at the baseline (2006-2010) from the UK Biobank, of which 15 194 participants had repeated measures of FAs between 2012 and 2013. Cox proportional hazards models were used to assess the association of the baseline and longitudinal changes in relative levels of plasma FAs (% total FAs) with incident gout. Mendelian randomization (MR) analyses were conducted to assess the potential causality of the examined association. Results: Over a median follow-up of 12.8 years, 5160 incident cases of gout occurred. Baseline polyunsaturated fatty acids (PUFAs), n-6 PUFAs, and linoleic acids (LAs) were inversely associated with incident gout (all P-trend values < 0.0001). Baseline monounsaturated fatty acids (MUFAs), n-3 PUFAs, and docosahexaenoic acids (DHAs) were positively associated with incident gout (all P-trend values < 0.0001). Longitudinal increments of n-6 PUFAs and LAs were associated with a lower risk of subsequent gout, whereas an increment of n-3 PUFAs was associated with a higher risk. In two-sample MR analyses, genetically determined higher levels of PUFAs, n-6 PUFAs, and LAs were associated with a decreased risk of gout (all P values < 0.05). Conclusions: Our findings consistently indicate a causal relationship of elevated levels of n-6 PUFAs, especially LAs, with a reduced risk of gout.

Physical Activity, Sleep, and Risk of Late-Onset Severe Mental Illness: A Prospective Cohort Study From UK Biobank.

BACKGROUND AND HYPOTHESIS: Previous studies have found that both physical inactivity and poor sleep are deleteriously associated with severe mental illness (SMI). The aim of current study was to investigate the joint association of physical activity (PA) and sleep with late-onset SMI (schizophrenia and bipolar disorder) risk. STUDY DESIGN: A total of 340 187 (for schizophrenia)/340 239 (for bipolar disorder) participants without schizophrenia or bipolar disorder from the UK Biobank were included. Baseline PA levels were categorized as high, intermediate, and low according to the total volume of PA. Sleep was categorized into healthy, intermediate, and poor according to an established composited sleep score of chronotype, sleep duration, insomnia, snoring, and daytime sleepiness. We derived 9 PA-sleep combinations, accordingly. STUDY RESULTS: After an average follow-up of 13.2 years, 814 participants experienced schizophrenia and 846 participants experienced bipolar disorder. Both low PA level, intermediate, and poor sleep were independently associated with increased risk of SMI. PA level and sleep had additive and multiplicative interactions on SMI risk. Compared to those with high PA level and healthy sleep, individuals with low PA and poor sleep had the highest risk of SMI (hazard ratio: 1.95; 95% CI: 1.02-3.70, P < .001) for schizophrenia; (hazard ratio: 3.81; 95% CI: 2.35-6.15) for bipolar disorder. A higher PA level may attenuate the detrimental effects of poor sleep. CONCLUSION: Both low PA and poor sleep was associated with increasing risk of late-onset SMI. Those with low PA and poor sleep had the highest risk of late-onset SMI, suggesting likely synergistic effects. Our findings supported the need to target both PA and sleep behaviors in research and clinical practice.

White matter hyperintensity, parent artery steno-occlusion, and neurological deterioration in anterior circulation single subcortical infarction patients.

BACKGROUND: The evidence for the association between white matter hyperintensity (WMH) severity and neurological deterioration (ND) in patients with single subcortical infarction (SSI) remains unclear and whether the association between them is modified by anterior circulation parent artery steno-occlusion (PAS) is unknown. Herein, we aimed to prospectively investigate the internal relevance. METHODS: In this prospective study, the severity of WMH and PAS were assessed in 288 consecutive patients with anterior circulation SSI arriving at our hospital, a tertiary teaching hospital affiliated with Fudan University, 24 h after onset from January 2017 to December 2018. The multivariable logistic regression model was used to estimate the association between WMH severity and the risk of ND within 7 days after stroke onset as well as the interactive effect between WMH severity and PAS on ND among patients with SSI. RESULTS: PAS modified the association between WMH severity and ND among patients with SSI (pinteraction = .029). After multivariate adjustment, the odds ratios of moderate-severe WMH associated with ND were 1.61 (95% CI, 0.50-5.19; ptrend = .428) for patients with PAS, and 0.37 (95% CI, 0.14-0.97; ptrend = .043) for those without PAS. Adding WMH severity to conventional risk factors improved risk prediction for ND in patients without PAS (net reclassification improvement: 48.2%, p = .005; integrated discrimination index: 2.5%, p = .004) but not in those with PAS. CONCLUSION: There was a modified effect of PAS on the association between WMH severity and ND within 7 days after stroke onset among patients with anterior circulation SSI, which deserves more research attention. WMH was negatively associated with ND in anterior circulation SSI patients without PAS.

Genetically Determined Plasma Hepatocyte Growth Factor Levels Are Associated With the Risk and Prognosis of Ischemic Stroke.

BACKGROUND: Observational studies suggest that hepatocyte growth factor (HGF) is associated with the risk and prognosis of ischemic stroke, but the causality of these associations remains unclear. Therefore, we conducted Mendelian randomization (MR) analyses to explore the associations of genetically determined plasma HGF levels with the risk and prognosis of ischemic stroke. METHODS: A total of 13 single-nucleotide polymorphisms associated with plasma HGF were selected as genetic instruments based on the data from a genome-wide association study with 21 758 European participants. Summary data about the risk of ischemic stroke were obtained from the MEGASTROKE (Multiancestry Genome-Wide Association Study of Stroke) Consortium with 34 217 ischemic stroke cases and 406 111 controls of European ancestry, and summary data about the prognosis of ischemic stroke were obtained from the GISCOME study (Genetics of Ischaemic Stroke Functional Outcome) with 6165 European patients with ischemic stroke. We conducted an inverse-variance weighted Mendelian randomization analysis followed by a series of sensitivity analyses to evaluate the associations of genetically determined plasma HGF with the risk and prognosis of ischemic stroke. RESULTS: The primary analyses showed that genetically determined high HGF was associated with an increased risk of ischemic stroke (odds ratio per SD increase, 1.11 [95% CI, 1.04-1.19]; P=1.10×10-3) and poor prognosis of ischemic stroke (odds ratio per SD increase, 2.43 [95% CI, 1.76-3.52]; P=6.35×10-8). In the secondary analysis, genetically determined plasma HGF was associated with a high risk of large atherosclerotic stroke (odds ratio per SD increase, 1.39 [95% CI, 1.18-1.63]; P=5.08×10-5) but not small vessel stroke and cardioembolic stroke. Mendelian randomization-Egger regression showed no directional pleiotropy for all associations, and the sensitivity analyses with different Mendelian randomization methods further confirmed these findings. CONCLUSIONS: We found positive associations of genetically determined plasma HGF with the risk and prognosis of ischemic stroke, suggesting that HGF might be implicated in the occurrence and development of ischemic stroke.

The identification of novel schizophrenia-related metabolites using untargeted lipidomics.

Human lipidome still remains largely unexplored among Chinese schizophrenia patients. We aimed to identify novel lipid molecules associated with schizophrenia and cognition among schizophrenia patients. The current study included 96 male schizophrenia patients and 96 gender-matched healthy controls. Untargeted lipidomics profiling was conducted among all participants. Logistic regression models were used to assess metabolite associations with schizophrenia. We further assessed the incremental predictive value of identified metabolites beyond conventional risk factors on schizophrenia status. In addition, identified metabolites were tested for association with cognitive function among schizophrenia patients using linear regression models. A total of 34 metabolites were associated with schizophrenia. Addition of these identified metabolites to age, body mass index, smoking, and education significantly increased the risk reclassification of schizophrenia. Among the schizophrenia-related metabolites, 10 were further associated with cognition in schizophrenia patients, including four metabolites associated with immediate memory, two metabolites associated with delayed memory, three metabolites associated with visuospatial, four metabolites associated with language, one metabolite associated with attention, and two metabolites associated with the total score. Our findings provide novel insights into the biological mechanisms of schizophrenia, suggesting that lipid metabolites may serve as potential diagnostic or therapeutic targets of schizophrenia.

Genetic analyses identify brain imaging-derived phenotypes associated with the risk of intracerebral hemorrhage.

Previous observational studies have reported associations between brain imaging-derived phenotypes (IDPs) and intracerebral hemorrhage (ICH), but the causality between them remains uncertain. We aimed to investigate the potential causal relationship between IDPs and ICH by a two-sample Mendelian randomization (MR) study. We selected genetic instruments for 363 IDPs from a genome-wide association study (GWASs) based on the UK Biobank (n = 33,224). Summary-level data on ICH was derived from a European-descent GWAS with 1,545 cases and 1,481 controls. Inverse variance weighted MR method was applied in the main analysis to investigate the associations between IDPs and ICH. Reverse MR analyses were performed for significant IDPs to examine the reverse causation for the identified associations. Among the 363 IDPs, isotropic or free water volume fraction (ISOVF) in the anterior limb of the left internal capsule was identified to be associated with the risk of ICH (OR per 1-SD increase, 4.62 [95% CI, 2.18-9.81], P = 6.63 × 10-5). In addition, the reverse MR analysis indicated that ICH had no effect on ISOVF in the anterior limb of the left internal capsule (beta, 0.010 [95% CI, -0.010-0.030], P = 0.33). MR-Egger regression analysis showed no directional pleiotropy for the association between ISOVF and ICH, and sensitivity analyses with different MR models further confirmed these findings. ISOVF in the anterior limb of the left internal capsule might be a potential causal mediator of ICH, which may provide predictive guidance for the prevention of ICH. Further studies are warranted to replicate our findings and clarify the underlying mechanisms.

The bidirectional association between frailty index and cardiovascular disease: A Mendelian randomization study.

BACKGROUND AND AIM: Observational studies have suggested a relationship between frailty and cardiovascular disease (CVD), but the causality is still uncertain. We used bidirectional Mendelian randomization (MR) design to investigate the potential causal associations between frailty and four main CVDs, including hypertension, myocardial infarction (MI), heart failure (HF), and atrial fibrillation (AF). METHODS AND RESULTS: Independent single-nucleotide polymorphisms for frailty index (FI) and CVDs (hypertension, MI, HF, and AF) were selected as genetic instruments based on European-descent genome-wide association studies (GWASs). Summary-level data for outcomes on FI (n = 175,226), hypertension (n = 463,010), MI (n = 171,875), HF (n = 977323), and AF (n = 1,030,836) was derived from five large-scale GWASs of European ancestry. We used the inverse-variance weighted (IVW) method to examine the bidirectional associations between FI and CVDs in the main analyses. In the IVW MR analyses, genetically determined high FI was significantly associated with increased risks of hypertension (odds ratio [OR] per 1-SD increase: 1.07 [95 % confidence interval, 1.05-1.08]), MI (OR per 1-SD increase: 1.74 [1.21-2.51]), HF (OR per 1-SD increase: 1.28 [1.10-1.48]), and AF (OR per 1-SD increase: 1.20 [1.08-1.33]). In addition, genetically determined hypertension (beta: 1.406 [1.225-1.587]), MI (beta: 0.045 [0.023-0.067]), HF (beta: 0.105 [0.066-0.143]) and AF (beta: 0.021 [0.012-0.031]) were significantly associated with high FI. These findings were robustly supported by a series of sensitivity analyses with different MR models. CONCLUSIONS: We found potential bidirectional causal associations between elevated FI and increased risks of CVD, suggesting mutual risk factors between frailty and CVD.

High-Serum Brain-Derived Neurotrophic Factor Levels Are Associated With Decreased Risk of Poststroke Cognitive Impairment.

BACKGROUND: BDNF (brain-derived neurotrophic factor) is widely implicated in the pathophysiological process of stroke, but the effect of BDNF on poststroke cognitive impairment (PSCI) remains unclear. We aimed to investigate the association between baseline serum BDNF and the risk of PSCI at 3 months in a multicenter study based on a preplanned ancillary study of the CATIS trial (China Antihypertensive Trial in Acute Ischemic Stroke). METHODS: We examined serum BDNF levels at baseline and used the Mini-Mental State Examination and Montreal Cognitive Assessment to evaluate cognitive function at 3-month follow-up after ischemic stroke. PSCI was defined as Mini-Mental State Examination score <27 or Montreal Cognitive Assessment score <25. Logistic regression analyses were performed to evaluate the association between serum BDNF and the risk of 3-month PSCI. RESULTS: In this ancillary study, a total of 660 patients with ischemic stroke with hypertension were included, and 593 patients (mean age, 59.90±10.44 years; 410 males and 183 females) were finally included in this analysis. According to mini-mental state examination score, after adjustment for age, sex, education, baseline National Institutes of Health Stroke Scale score, APOE ɛ4 carriers, and other potential confounders, the odds ratio of PSCI for the highest tertile of BDNF was 0.60 ([95% CI, 0.39-0.94]; P=0.024) compared with the lowest tertile. Multiple-adjusted spline regression model showed a linear association of serum BDNF levels with PSCI at 3 months (P value for linearity=0.010). Adding serum BDNF to conventional prognostic factors slightly improved the risk reclassification of PSCI (net reclassification improvement: 27.46%, P=0.001; integrated discrimination index: 1.02%, P=0.015). Similar significant findings were observed when PSCI was defined by the Montreal Cognitive Assessment score. CONCLUSIONS: Elevated serum BDNF levels were associated with a decreased risk of PSCI at 3 months, suggesting that serum BDNF might be a potential predictive biomarker for PSCI among patients with ischemic stroke with hypertension.

Association between Plasma Brain-derived Neurotrophic Factor Level and Alzheimer's Disease: A Mendelian Randomization Study.

BACKGROUND: High brain-derived neurotrophic factor (BDNF) concentrations have been found to be associated with a decreased risk of Alzheimer's disease (AD) in observational studies, but the causality for this association remains unclear. Therefore, we aimed to examine the association between genetically determined plasma BDNF levels and AD using a two-sample Mendelian randomization (MR) method. METHODS: Twenty single-nucleotide polymorphisms associated with plasma BDNF concentrations were identified as genetic instruments based on a genome-wide association study with 3301 European individuals. Summary-level data on AD were obtained from the International Genomics of Alzheimer's Project, involving 21,982 AD cases and 41,944 controls of European ancestry. To evaluate the relationship between plasma BDNF concentrations and AD, we employed the inverse-variance weighted method along with a series of sensitivity analyses. RESULTS: The inverse-variance weighted MR analysis showed that genetically determined BDNF concentrations were associated with a decreased risk of AD (odds ratio per SD increase, 0.91; 95% confidence interval, 0.86-0.96; p =0.001). The association between plasma BDNF concentrations and AD was further confirmed through sensitivity analyses using different MR methods, and MR-Egger regression suggested no directional pleiotropy for this association. CONCLUSION: Genetically determined BDNF levels were associated with a decreased risk of AD, suggesting that BDNF was implicated in the development of AD and might be a promising target for the prevention of AD.

Genetic analyses identify brain imaging-derived phenotypes associated with the risk of amyotrophic lateral sclerosis.

Brain imaging-derived phenotypes have been suggested to be associated with amyotrophic lateral sclerosis in observational studies, but whether these associations are causal remains unclear. We aimed to assess the potential bidirectional causal associations between imaging-derived phenotypes and amyotrophic lateral sclerosis using bidirectional 2-sample Mendelian randomization analyses. Summary statistics for 469 imaging-derived phenotypes (33,224 individuals) and amyotrophic lateral sclerosis (20,806 cases and 59,804 controls) were obtained from 2 large-scale genome-wide association studies of European ancestry. We used the inverse-variance weighted Mendelian randomization method in the main analysis to assess the bidirectional associations between imaging-derived phenotypes and amyotrophic lateral sclerosis, followed by several sensitivity analyses for robustness validation. In the forward Mendelian randomization analyses, we found that genetically determined high orientation dispersion index in the right cerebral peduncle was associated with the increased risk of amyotrophic lateral sclerosis (odds ratio = 1.30, 95% confidence interval = 1.16-1.45, P = 2.26 × 10-6). In addition, the reverse Mendelian randomization analysis indicated that amyotrophic lateral sclerosis had no effect on 469 imaging-derived phenotypes. Mendelian randomization-Egger regression analysis showed no directional pleiotropy for the association between high orientation dispersion index in the right cerebral peduncle and amyotrophic lateral sclerosis, and sensitivity analyses with different Mendelian randomization models further confirmed these findings. The present systematic bidirectional Mendelian randomization analysis showed that high orientation dispersion index in the right cerebral peduncle might be the potential causal mediator of amyotrophic lateral sclerosis, which may provide predictive guidance for the prevention of amyotrophic lateral sclerosis. Further studies are warranted to replicate our findings and clarify the underlying mechanisms.