Associations of Sedentary Behavior with Risks of Cardiovascular Disease Events among Chinese Adults.

AIMS: Evidence regarding the modification effects of age, sex, ethnicity, socioeconomic status, or weight status on the associations of sedentary behavior (SB) with cardiovascular diseases (CVDs) is limited. Moreover, the mechanisms for the associations also remain unclear. We aimed to investigate the possible influence of these factors on the associations of SB with CVD events and whether the associations are mediated by metabolic phenotypes. METHODS: This study included 42,619 participants aged 20-74 years, recruited from the Shanghai Suburban Adult Cohort and Biobank study. SB was assessed at baseline and integrated with health information systems to predict future CVD events. Cox proportional hazards models, interaction analyses, restricted cubic splines and causal mediation analyses were used for assessments. RESULTS: Compared to those with ＜3 h/d sedentary time, participants having SB ≥ 5 h/d had significantly higher risks of CVD (HR[95%CI]: 1.27[1.12-1.44]), coronary heart disease (CHD, 1.35[1.14-1.60]), and ischemic stroke (IS, 1.30[1.06-1.60]). The association of CHD was more pronounced in the retired individuals than their counterparts (1.45[1.20-1.76] versus 1.06[0.74-1.52], pinteraction=0.046). When SB was expressed as a continuous variable, a 1 h/d increment in SB was positively associated with risks of CVD (1.03[1.01-1.05]), CHD (1.04[1.01-1.07]), and IS (1.05[1.01-1.08]). High-density lipoprotein cholesterol (HDL-C, proportion mediated: 12.54%, 12.23%, and 11.36%, all p＜0.001), followed by triglyceride (TG, 5.28%, 4.77%, and 4.86%, all p＜0.01) and serum uric acid (SUA, 3.64%, 4.24%, and 2.29%, all p＜0.05) were major mediators through metabolic phenotypes. CONCLUSIONS: Higher SB was associated with elevated risks of CVD events. The detrimental effect of SB on CHD risk was more pronounced among retired individuals. Moreover, HDL-C, TG and SUA partially mediated the relationships between SB and CVD events. Our findings may have implications for preventing and controlling CVD associated with SB.

Varying Definitions of Carotid Intima-Media Thickness and Future Cardiovascular Disease: A Systematic Review and Meta-Analysis.

BACKGROUND: Carotid intima-media thickness (cIMT) has been widely used as a predictor of future cardiovascular disease (CVD); however, various definitions of cIMT exist. This study provides a systematic review and meta-analysis of the associations between different cIMT definitions and CVD. METHODS AND RESULTS: A systematic review of the different cIMT definitions used in prospective cohort studies was performed. The relationships between cIMT of different definitions (common carotid artery IMT [CCA-IMT], internal carotid artery IMT [ICA-IMT], combined segments [combined-IMT], mean CCA-IMT, and maximum CCA-IMT) with future stroke, myocardial infarction (MI), and CVD events were analyzed using random effects models. Among 2287 articles, 18 articles (14 studies) with >10 different cIMT definitions were identified and included in our meta-analysis. After adjusting for age and sex, a 1-SD increase in CCA-IMT was associated with future stroke (hazard ratio [HR], 1.32 [95% CI, 1.27-1.38]), MI (HR, 1.27 [95% CI, 1.22-1.33]), and CVD events (HR, 1.28 [95% CI, 1.19-1.37]). A 1-SD increase in ICA-IMT was related to future stroke (HR, 1.25 [95% CI, 1.11-1.42]) and CVD events (HR, 1.25 [95% CI, 1.04-1.50]) but not MI (HR, 1.26 [95% CI, 0.98-1.61]). A 1-SD increase in combined-IMT was associated with future stroke (HR, 1.30 [95% CI, 1.08-1.57]) and CVD events (HR, 1.36 [95% CI, 1.23-1.49]). Maximum CCA-IMT was more strongly related than mean CCA-IMT with risk of MI, and both measures were similarly associated with stroke and CVD events. CONCLUSIONS: Combined-IMT is more strongly associated with CVD events compared with single-segment cIMT definitions. Maximum CCA-IMT shows a stronger association with MI than mean CCA-IMT. Further research is warranted to validate our findings and to standardize the cIMT measurement protocol, as well as to explore underlying mechanisms.

Association of triglyceride-glucose index with cardiovascular disease among a general population: a prospective cohort study.

BACKGROUND: The impact of triglyceride-glucose (TyG) index, a surrogate marker for insulin resistance, on the risk of cardiovascular disease (CVD) in general populations remains controversial. We aimed to comprehensively study the relationship between TyG index with the risk of incident CVD events in the general population in Shanghai. METHODS: A total of 42,651 participants without previous history of CVD events from Shanghai Suburban Adult Cohort and Biobank (SSACB) were included. SSACB was a community-based natural population cohort study using multistage cluster sampling method. TyG index was calculated as Ln [fasting serum triglyceride (mg/dL) * fasting blood glucose (mg/dL)/2]. Kaplan-Meier curves, log-rank test and cox proportional hazards model were used to calculate the association between TyG index and incident CVD, including stroke and coronary heart disease (CHD). Restricted cubic spline analyses were used to determine whether there was a non-linear relationship between TyG index and CVD events. RESULTS: During a median follow-up of 4.7 years, 1,422 (3.3%) individuals developed CVD, including 674 (1.6%) cases of stroke and 732 (1.7%) cases of CHD. A one unit increment higher TyG index was associated with [HR(95%CI)] 1.16(1.04-1.29) in CVD and with 1.39(1.19-1.61) in stroke. Only linear relationships between TyG and CVD/stroke were observed, while no relationship was observed with CHD after adjustments for confounders. In subgroup analyses, younger (< 50y) and diabetic participants had higher risk of CVD than their counterpart groups, while hypertensive and dyslipidemic participants depicted lower risks than their counterparts. CONCLUSION: Elevated TyG index was associated with a higher risk of incident CVD and stroke. TyG index may help in the early stage of identifying people at high risk of CVD.