HDL-cholesterol and prediction of coronary heart disease: Modified by physical fitness?

A dose-response meta-analysis to evaluate the relationship between high-density lipoprotein cholesterol and all-cause and cardiovascular disease mortality

PURPOSE

Previous studies have not fully described the relationship between high-density lipoprotein cholesterol (HDL-C) and death risks from all cause and cardiovascular disease (CVD). This study quantitatively evaluates HDL-C-mortality associations.

METHODS

Embase and PubMed databases were searched for relevant articles published up to 1 June 2019. Random-effects models were used to pool relative risks (RRs) and 95% confidence intervals (CIs). We used restricted cubic splines to model the dose-response association.

RESULTS

We identified 32 prospective cohort studies including 369,904 participants and 33,473 total deaths (9426 CVD deaths). Compared to the lowest HDL-C levels, all cause and CVD mortality risks were reduced by 18% (RR 0.82; 95% CI, 0.73-0.93) and 36% (0.64, 0.46-0.89), respectively, for the highest HDL-C levels. All cause and CVD mortality risks were reduced by 15% (0.85, 0.79-0.92) and 23% (0.77, 0.69-0.87), respectively, with each 1 mmol/L increment of HDL-C. We found evidence of nonlinear and negative dose-response associations of HDL-C with all cause and CVD mortality (P_nonlinearity < 0.001), and the lowest death risks from all cause and CVD were observed at approximately 1.34 and 1.55 mmol/L, respectively.

CONCLUSION

HDL-C is inversely associated with all cause and CVD mortality risks under approximately 2.05 and 2.33 mmol/L, respectively. Optimal doses require investigation via clinical practice or high-quality research.

Association of Physical Activity with Lipid Profile in Healthy Subjects: A Cross Sectional Study in Tertiary Care Hospital from Central Rural India

CONTEXT

Physical activity is an important factor for healthy aging, and lack of it has been associated with chronic noncommunicable diseases (NCDs). Research in sedentary behavior has indicated that it is an independent risk factor of morbidity and mortality, separate from lack of physical activity.

METHODS

This cross-sectional study was conducted in the department of medicine in a tertiary care hospital on apparently healthy relatives of patients without chronic NCDs. Metabolic equivalents of tasks (METs) were calculated by the global physical activity questionnaire (GPAQ).

STATISTICAL ANALYSIS

We correlated the various parameters [age, sex, body mass index (BMI), waist-hip ratio (WHR), and lipid panel with METs] by Pearson correlation coefficient.

OBSERVATIONS AND RESULTS

Total of 750 patients with a mean age of 42.55 ± 10.93 years were included, and 389 (51.9%) were male in the present study. In our study, a strong negative correlation was found between physical activity and BMI, moderate negative correlation between physical activity with triglycerides (TG), total cholesterol (TC), and WHR. There was a high degree of positive correlation between sedentary lifestyle (SLS) duration with BMI and TC. A moderate degree positive correlation was found between SLS duration and WHR, TG, and low-density lipoproteins (LDL).

CONCLUSION

The clinician should be aware of various obesity indices, and it was found that lipid profile is inversely correlated with physical activity and directly correlated with SLS in healthy individuals. Lifestyle changes and exercise may reduce obesity and lipid disorders and thereby reduce further development of complications in those patients.

Joint modelling of longitudinal lipids and time to coronary heart disease in the Jackson Heart Study

BACKGROUND

Multiple longitudinal responses together with time-to-event outcome are common in biomedical studies. There are several instances where the longitudinal responses are correlated with each other and at the same time each longitudinal response is associated with the survival outcome. The main purpose of this study is to present and explore a joint modeling approach for multiple correlated longitudinal responses and a survival outcome. The method will be illustrated using the Jackson Heart Study (JHS), which is one of the largest cardiovascular studies among African Americans.

METHODS

Four longitudinal responses, i.e., total cholesterol (TC), high density lipoprotein (HDL) cholesterol, triglyceride (TG) and inflammation measured by high-sensitivity C-reactive protein (hsCRP); and time-to-coronary heart disease (CHD) were considered from the JHS. The repeated lipid and hsCRP measurements from a given subject overtime are likely correlated with each other and could influence the subject's risk for CHD. A joint modeling framework is considered. To deal with the high dimensionality due to the multiple longitudinal profiles, we use a pairwise bivariate model fitting approach that was developed in the context of multivariate Gaussian random effects models. The method is further explored through simulations.

RESULTS

The proposed model performed well in terms of bias and relative efficiency. The JHS data analysis showed that lipid and hsCRP trajectories could exhibit interdependence in their joint evolution and have impact on CHD risk.

CONCLUSIONS

We applied a unified and flexible joint modeling approach to analyze multiple correlated longitudinal responses and survival outcome. The method accounts for the correlation among the longitudinal responses as well as the association between each longitudinal response and the survival outcome at once. This helps to explore how the combination of multiple longitudinal trajectories could be related to the survival process.

Lipid efflux mechanisms, relation to disease and potential therapeutic aspects

Lipids are hydrophobic and amphiphilic molecules involved in diverse functions such as membrane structure, energy metabolism, immunity, and signaling. However, altered intra-cellular lipid levels or composition can lead to metabolic and inflammatory dysfunction, as well as lipotoxicity. Thus, intra-cellular lipid homeostasis is tightly regulated by multiple mechanisms. Since most peripheral cells do not catabolize cholesterol, efflux (extra-cellular transport) of cholesterol is vital for lipid homeostasis. Defective efflux contributes to atherosclerotic plaque development, impaired β-cell insulin secretion, and neuropathology. Of these, defective lipid efflux in macrophages in the arterial walls leading to foam cell and atherosclerotic plaque formation has been the most well studied, likely because a leading global cause of death is cardiovascular disease. Circulating high density lipoprotein particles play critical roles as acceptors of effluxed cellular lipids, suggesting their importance in disease etiology. We review here mechanisms and pathways that modulate lipid efflux, the role of lipid efflux in disease etiology, and therapeutic options aimed at modulating this critical process.

HDL-C is associated with mortality from all causes, cardiovascular disease and cancer in a J-shaped dose-response fashion: a pooled analysis of 37 prospective cohort studies

Objective

The association between high-density lipoprotein cholesterol (HDL-C) levels and mortality remains controversial. We aimed to investigate the potential dose–response associations between HDL-C levels and mortality from all causes, cardiovascular disease and cancer in the general population.

Methods

PubMed and Embase were searched through April 2019. Prospective cohort studies reporting risk estimates of HDL-C levels and mortality were included. Linear and non-linear dose–response analyses were conducted. A random-effects model was employed to calculate pooled hazard ratio.

Results

Thirty-seven studies, involving 3,524,505 participants and more than 612,027 deaths, were included. HDL-C level was found to be associated with mortality from all causes, cardiovascular disease and cancer in a J-shaped dose–response pattern, with the lowest risk observed at HDL-C levels of 54–58 mg/dL, 68–71 mg/dL and 64–68 mg/dL, respectively. Compared with HDL-C level of 56 mg/dL, the pooled hazard ratios for all-cause mortality were 1.03 (95% confidence interval (CI) 1.01, 1.05) and 1.10 (95% CI 1.09, 1.12) for each 10-mg/dL increase and decrease in HDL-C levels, respectively; furthermore, compared with the reference category, the pooled hazard ratios for all-cause mortality were 1.21 (95% CI 1.09, 1.36) and 1.36 (95% CI 1.21, 1.53) for the highest and the lowest categories of HDL-C levels, respectively. Similar results were obtained for cardiovascular and cancer mortality.

Conclusions

In the general population, HDL-C level is associated with mortality from all causes, cardiovascular disease and cancer in a J-shaped dose–response manner; both extremely high and low HDL-C levels are associated with an increased risk of mortality.

Exercise Systolic Blood Pressure at Moderate Workload Is Linearly Associated With Coronary Disease Risk in Healthy Men

There is no consensus on the definition of an exaggerated increase in systolic blood pressure (SBP) during exercise. The aim was to explore a potential threshold for exercise SBP associated with increased risk of coronary heart disease in healthy men using repeated exercise testing. Two thousand fourteen healthy white male employees were recruited into the Oslo Ischemia Study during early 1970s. At follow-up 7 years later, 1392 men were still considered healthy. A bicycle exercise test at 100 W workload was performed at both visits. Cox regression analyses were performed with increasing cutoff levels of peak exercise SBP at 100 W workload (SBP100W) from 160 mm Hg to 200 mm Hg, adjusted for cardiovascular risk factors and physical fitness. Participants with SBP100W below cutoff level at both baseline and first follow-up were compared with participants with SBP100W equal to or above cutoff level at both visits. Compared with participants with SBP100W below all cutoff levels between 165 and 195 mm Hg, coronary heart disease risk was increased among participants with SBP100W equal to or above cutoff at all levels. There was no evidence of a distinct threshold level for coronary heart disease risk, and the relation between SBP100W and coronary heart disease appears linear. When investigating exercise SBP at moderate workload measured at 2 exercise tests in healthy middle-aged white men, there is increasing risk of coronary heart disease with increasing exercise SBP independent of SBP at rest. The association is linear from the low range of exercise SBP, and there is no sign of a distinct threshold level for increased coronary disease risk.

Effects of vitamin D supplementation along with endurance physical activity on lipid profile in metabolic syndrome patients: A randomized controlled trial

BACKGROUND AND OBJECTIVES

This study was conducted to determine the effects of vitamin D supplementation along with endurance physical activity on lipid profile among metabolic syndrome patients.

MATERIALS AND METHODS

In a parallel randomized placebo controlled trial, 70 metabolic syndrome patients, were randomly assigned into three groups. Biochemical tests were assessed as baseline and after 12 weeks of intervention. Statistical analysis was performed using SPSS version 20.

RESULTS

The mean vitamin D levels was increased significantly in both vitamin D and vitamin D plus physical activity groups (P value < 0.05). No significant change was observed in the placebo group. Additionally, there was a significant decrease in total cholesterol and LDL-C in vitamin D plus physical activity group (P value < 0.05). No significant differences in changes of triglycerides and HDL-C among the three groups (P value > 0.05). While, in vitamin D group a decreased in total cholesterol, HDL-C, LDL-C and increase in triglycerides were observed, but did not reach a statistically significant.

CONCLUSION

Daily supplementation of vitamin D for 12 weeks, along with moderate endurance physical activity, significantly increase vitamin D concentration and induce a significant reduction in lipid profile in metabolic syndrome patients.

Analysis of Machine Learning Algorithms in Health Care to Predict Heart Disease

This article describes how healthcare organizations is growing increasingly and are the potential beneficiary users of the data that is generated and gathered. From hospitals to clinics, data and analytics can be a very powerful tool that can improve patient care and satisfaction with efficiency. In developing countries, cardiovascular diseases have a huge impact on increasing death rates and are expected by the end of 2020 in spite of the best clinical practices. The current Machine Learning (ml) algorithms are adapted to estimate the heart disease risks in middle aged patients. Hence, to predict the heart diseases a detailed analysis is made in this research work by taking into account the angiographic heart disease status (i.e. ≥ 50% diameter narrowing). Deep Neural Network (DNN), Extreme Learning Machine (elm), K-Nearest Neighbor (KNN) and Support Vector Machine (SVM) learning algorithm (with linear and polynomial kernel functions) are considered in this work. The accuracy and results of these algorithms are analyzed by comparing the effectiveness among them.

Association Between Paradoxical HDL Cholesterol Decrease and Risk of Major Adverse Cardiovascular Events in Patients Initiated on Statin Treatment in a Primary Care Setting

BACKGROUND AND OBJECTIVES

Statin-induced changes in high-density lipoprotein cholesterol (HDL-C) and low-density lipoprotein cholesterol (LDL-C) are unrelated. Many patients initiated on statins experience a paradoxical decrease in HDL-C. The aim of this study was to evaluate the association between a decrease in HDL-C and risk of major adverse cardiovascular events (MACE).

METHODS

Data from 15,357 primary care patients initiated on statins during 2004-2009 were linked with data from mandatory national hospital, drug-dispensing, and cause-of-death registers, and were grouped according to HDL-C change: decreased ≥0.1 mmol/L, unchanged ±0.1 or ≥0.1 mmol/L increased. To evaluate the association between decrease in HDL-C and risk of MACE, a sample of propensity score-matched patients from the decreased and unchanged groups was created, using the latter group as reference. MACE was defined as myocardial infarction, unstable angina pectoris, ischaemic stroke, or cardiovascular mortality. Cox proportional hazards models were used to estimate relative risks.

RESULTS

HDL-C decreased in 20%, was unchanged in 58%, and increased in 22% of patients initiated on statin treatment (96% treated with simvastatin). The propensity score-matched sample comprised 5950 patients with mean baseline HDL-C and LDL-C of 1.69 and 4.53 mmol/L, respectively. HDL-C decrease was associated with 56% higher MACE risk (hazard ratio 1.56; 95% confidence interval 1.12-2.16; p < 0.01) compared with the unchanged HDL-C group.

CONCLUSIONS

Paradoxical statin-induced reduction in HDL-C was relatively common and was associated with increased risk of MACE.

Physical Activity and Lipid Profile in the ELSA- Brasil Study

Background

Regular physical activity (PA) induces desirable changes in plasma levels of high- and low-density lipoproteins (HDL and LDL, respectively) and triglycerides (TG), important risk factors for cardiometabolic diseases. However, doubts whether intensity and duration have equivalent benefits remain.

Objective

To assess the association of PA intensity and duration with HDL, LDL and TG levels.

Methods

Cross-sectional study with 12,688 participants from the Brazilian Longitudinal Study of Adult Health (ELSA-Brasil) baseline, who were not on lipid-lowering medication. After adjustment for important covariates, multiple linear regression was used to assess the association of PA intensity and duration with HDL, LDL and TG (natural logarithm) levels.

Results

Both moderate and vigorous PA and PA practice ≥ 150 min/week were significantly associated with higher HDL and lower TG levels. Vigorous PA was associated with lower LDL only on univariate analysis. After adjustments, moderate and vigorous PA increased mean HDL level by 0.89 mg/dL and 1.71 mg/dL, respectively, and reduced TG geometric mean by 0.98 mg/dL and 0.93 mg/dL, respectively. PA practice ≥ 150 min/week increased mean HDL level by 1.05 mg/dL, and decreased TG geometric mean by 0.98 mg/dL.

Conclusion

Our findings reinforce the benefits of both PA parameters studied on HDL and TG levels, with a slight advantage for vigorous PA as compared to the recommendation based only on PA duration.

Predictors of abdominal adipose tissue compartments: 18-year follow-up of young men with and without family history of diabetes

BACKGROUND

Abdominal adipose tissue (AAT) consists of visceral adipose tissue (VAT) and subcutaneous adipose tissue (SAT), which can be further divided into superficial and deep SAT. Despite being a key factor in the development of metabolic and cardiovascular diseases, what predicts future amount of AAT is largely unknown.

OBJECTIVE

To determine long-term predictors of amount of AAT.

METHODS

This was a mean 18-year follow-up study of a cohort of 94 healthy young Caucasian men, with and without a family history of diabetes (FHD). Cardiovascular risk markers were examined both at baseline and at follow-up. At follow-up, computed tomography (CT) of AAT was conducted to assess amount of superficial and deep SAT, and VAT.

RESULTS

In multiple regression analyses, baseline body mass index (BMI) remained a positive predictor of future amount of superficial and deep SAT, while high-density lipoprotein (HDL) cholesterol was a negative predictor of all three sub-compartments. Baseline risk markers were generally stronger predictors among men with FHD, than among men without. In addition, FHD had greater impact on amount of deep SAT and VAT, than on amount of superficial SAT.

CONCLUSION

Our data suggest that the traditional cardiovascular risk markers BMI, HDL cholesterol and family history of diabetes are long-term predictors of the different abdominal adipose tissue compartments from young towards middle age in healthy men. In men with family history of diabetes, cardiovascular risk markers at a young age seem to be of greater importance to future amount of abdominal adipose tissue, than among men without.

The association between cardiorespiratory fitness and cardiovascular risk may be modulated by known cardiovascular risk factors

BACKGROUND

We aimed to evaluate whether reduced cardiovascular fitness has a direct or indirect effect for the development of cardiovascular disease.

METHODS

We investigated 15,595 men and women who were annually screened in a tertiary medical center. All subjects were free of ischemic heart disease and had completed maximal exercise stress test according to the Bruce protocol at their first visit. Fitness was categorized into age- and sex-specific quintiles (Q) according to Bruce protocol treadmill time with Q1 as lowest fitness. Subjects were categorized at baseline into 3 groups: low fitness (Q1), moderate fitness (Q2-Q4), and high fitness (Q5). The primary end point of the current analysis was the development of a first cardiovascular event during follow-up.

RESULTS

Mean age of study patients was 48 ± 10 years, and 73% were men. A total of 679 events occurred during 92,092 person-years of follow-up. Kaplan-Meier survival analysis showed that the cumulative probability of cardiovascular events at 6 years was significantly higher among subjects with low fitness (P < .001). Low fitness was associated with known cardiovascular risk factors, including hypercholesterolemia (odds ratio [OR] 1.58, 95% CI 1.31-1.89), diabetes mellitus (OR 2.32, 95% CI 1.58-3.41), and obesity (OR 10.46, 95% CI 8.43-12.98). The effect of low fitness on cardiovascular events was no longer significant when including diabetes mellitus, hypercholesterolemia, and obesity as mediators (hazard ratio 0.99, 95% CI 0.82-1.19).

CONCLUSIONS

The association between cardiovascular fitness and adverse cardiovascular outcomes may be modulated through traditional cardiovascular risk factors. These findings need to be further validated in prospective clinical trials.

Triglycerides-diabetes association in healthy middle-aged men: modified by physical fitness? A long term follow-up of 1962 Norwegian men in the Oslo Ischemia Study

AIMS

To examine the impact of physical fitness (PF) on the association between fasting serum triglycerides (FTG) and diabetes risk and whether temporal changes in FTG predict diabetes risk in healthy middle-aged men.

METHODS

FTG and PF (bicycle exercise test) were measured in 1962 men aged 40-59 years in 1972-1975 (Survey 1) and repeated in 1387 still healthy men on average 7.3 years later (Survey 2). Diabetes was diagnosed according to WHO 1985-criteria.

RESULTS

During 35 years follow-up 202/1962 (10.3%) men developed diabetes. Compared with the lowest, the upper FTG tertile had a 2.58-fold (95% CI: 1.81-3.74) diabetes risk adjusted for age, fasting blood glucose and maternal diabetes, and a 2.29-fold (95%CI: 1.60-3.33) when also adjusting for PF. Compared with unchanged (±25%) FTG levels (n=664), FTG reduction of more than 25% (n=261) was associated with 56% lower (0.44; 95% CI: 0.24-0.75) diabetes risk, while FTG increase of more than 25% (n=462) was associated with similar risk. These associations were unchanged when adjusted for PF and PF change.

CONCLUSIONS

High FTG-levels predicted long-term diabetes risk in healthy middle-aged men, and the association was only modestly weakened when adjusted for PF. A reduction in FTG was associated with decreased diabetes risk.

Arctium lappa ameliorates endothelial dysfunction in rats fed with high fat/cholesterol diets

Background

Arctium lappa L. (Asteraceae), burdock, is a medicinal plant that is popularly used for treating hypertension, gout, hepatitis, and other inflammatory disorders. This study was performed to test the effect of ethanol extract of Arctium lappa L. (EAL) seeds on vascular reactivity and inflammatory factors in rats fed a high fat/cholesterol diet (HFCD).

Method

EAL-I (100 mg·kg⁻¹/day), EAL-II (200 mg·kg⁻¹/day), and fluvastatin (3 mg·kg⁻¹/day) groups initially received HFCD alone for 8 weeks, with EAL supplementation provided during the final 6 weeks.

Results

Treatment with low or high doses of EAL markedly attenuated plasma levels of triglycerides and augmented plasma levels of high-density lipoprotein (HDL) in HFCD-fed rats. Chronic treatment with EAL markedly reduced impairments of acetylcholine (ACh)-induced relaxation of aortic rings. Furthermore, chronic treatment with EAL significantly lowered systolic blood pressure (SBP) and maintained smooth and flexible intimal endothelial layers in HFCD-fed rats. Chronic treatment with EAL suppressed upregulation of intercellular adhesion molecule (ICAM)-1, vascular cell adhesion molecule (VCAM)-1, and E-selectin in the aorta. Chronic treatment with EAL also suppressed increases in matrix metalloproteinase (MMP)-2 expression. These results suggested that EAL can inhibit HFCD-induced vascular inflammation in the rat model.

Conclusion

The present study provides evidence that EAL ameliorates HFCD-induced vascular dysfunction through protection of vascular relaxation and suppression of vascular inflammation.