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This review provides a practical guide to the essentials of survival analysis and their reporting in cardiovascular studies, although most of its key content can be extrapolated to other medical fields. This is the first in a series of 2 educational articles laying the groundwork to address the most relevant statistical issues in survival analyses, which will smoothly drive the reader from the most basic analyses to the most complex situations. The focus will be on the type and shape of survival data, and the most common statistical methods, such as nonparametric, parametric and semiparametric models. Their adequacy, interpretation, advantages and disadvantages are illustrated by examples from the field of cardiovascular research. This article ends with a set of recommendations to guide the strategy of survival analyses for a randomized clinical trial and observational studies. Other topics, such as competing risks, multistate models and recurrent-event methods will be addressed in the second article.  相似文献   
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Background and aimsReducing dietary cholesterol is generally acceptable for the prevention of cardiovascular disease (CVD). Eggs are nutrient-dense and common food items across the world, while rich in cholesterol. The potential effects of egg intake on cardiovascular health remain uncertainty and have been under debate in past decades.Methods and resultsA nationwide cohort of 20,688 participants aged 16–110 years without CVD at baseline were derived from the China Family Panel Studies. Egg consumption was assessed by a semi-quantitative food frequency questionnaire. We adopted stratified Cox proportional hazards model with random intercepts for provinces to evaluate associations of egg intake with CVD incidence. During a median follow-up of 6.0 years, we identified 2395 total CVD incidence and mean egg consumption was 3 times/week. Egg intakes were associated lower risks of CVD incidence in the multivariate-adjusted model. Compared with the non-consumers, the corresponding HRs (95% confidence interval) for total CVD events were 0.84 (0.74–0.94) for 1–2 times per week, 0.78 (0.69–0.88) for 3–6/week, and 0.83 (0.72–0.95) for ≥7/week. Similar relationships were found in hypertension. Approximately non-linear relationships were observed between egg consumption with total CVD and hypertension incidence, identifying the lowest risk in 3–6 times/week. Subgroup analyses estimated lower risks of total CVD and hypertension in females only, with significant effect modification by sex (P for interaction = 0.008 and 0.020).ConclusionEgg consumption may be associated with lower risks of CVD incidence among Chinese adults. Our findings could have implications in CVD prevention and might be considered in the development of dietary guidelines.  相似文献   
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ObjectiveTo assess the association between adherence to a Mediterranean lifestyle and changes in pain, and its characteristics over time in older adults.Patients and MethodsWe analyzed data from 864 and 862 community-dwelling individuals aged 65+ years from the Study on Cardiovascular Health, Nutrition and Frailty in Older Adults in Spain (Seniors-ENRICA) Seniors-ENRICA-1 (2008–2010 to 2012) and Seniors-ENRICA-2 (2015–2017 to 2019) cohorts, with a median follow-up of 2.8 and 2.4 years, respectively. Adherence to a Mediterranean lifestyle was assessed at baseline with the 27-item Mediterranean lifestyle (MEDLIFE) index. Pain changes over time were calculated with a pain scale that assessed the frequency, severity, and the number of pain locations both at baseline and follow-up. Multivariable-adjusted relative risk ratios (RRRs) were obtained using multinomial logistic regression.ResultsIn the pooled cohorts, after a median follow-up of 2.6 years, pain worsened for 697 participants, improved for 734, and did not change for 295. Compared with the lowest category of MEDLIFE adherence, those in the highest category showed an RRR of improvement vs worsening of overall pain of 1.85 (95% CI, 1.28 to 2.67; P-trend<.001). MEDLIFE adherence was also linked to improvement in pain frequency (RRR, 1.98; 95% CI, 1.31 to 3.01; P-trend=.001), pain severity (RRR, 2.00; 95% CI, 1.33 to 3.00; P-trend=.001), and a reduction in the number of pain locations (RRR, 1.68; 95% CI, 1.13 to 2.50; P-trend=.004). Limitations of this study are the use of self-reported lifestyle data.ConclusionA Mediterranean lifestyle was associated with improvement of pain characteristics in older adults. Experimental studies should assess the efficacy of an integral lifestyle approach for the management of pain in older adults.  相似文献   
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社区动脉粥样硬化风险(ARIC)研究是1987年由美国心、肺和血液研究所资助的关注非洲裔美国人心血管健康的最大研究。旨在调查心脏病的危险因素以及心血管疾病与认知之间的联系。ARIC研究的许多发现加深了对动脉粥样硬化性心血管病病因的了解,在心血管病预防领域做出了重大贡献,证明了以人群为基础的研究对改善健康和预防疾病的重要性。主要概述ARIC研究的起源、目的、研究设计、对心血管医学的贡献以及未来的发展方向。  相似文献   
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PurposeCompared with healthy individuals, patients with peripheral artery disease (PAD) generally have a very high risk of subclinical Coronary artery disease (CAD) and cardiovascular events. To determine the correlation between CAD in PAD patients, thereby promoting the lifetime of PAD patients and reducing the serious impacts of CAD.MethodsThis clinical-based cross-sectional study comprised 100 consecutive patients in India from 2014 to 2016. In this research, PAD patients were screened for CAD by treadmill stress test and cardiac colour Doppler examination. In addition, this study performed coronary angiography followed by peripheral angiography for patients who could not perform the treadmill test.ResultsWith the statistical results, the study observed a high prevalence of CAD in PAD patients that can be detected only with angiography. Further, 30.93% of asymptomatic CAD prevalence was observed in PAD patients. The study strengthens the need for coronary angiography in all symptomatic lower limb PAD cases to detect early CAD, particularly in patients with diabetes and dyslipidemia.ConclusionThere exists a strong correlation between PAD and CAD. Hence, precise diagnosis followed by supervision of PAD patients is significant for avoiding local progression of cardiovascular risk.  相似文献   
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