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

Fibrates, Hypertriglyceridemia, and CVD Risk: Where Do We Stand After the PROMINENT Trial for Triglyceride Lowering?

PURPOSE OF REVIEW

To evaluate recent clinical trials focusing on patients with hypertriglyceridemia.

RECENT FINDINGS

Randomized clinical trials have recently been undertaken in hypertriglyceridemic patients to determine whether effective reductions in triglycerides would improve cardiovascular disease (CVD) outcomes. However, the fibric acid derivative, pemafibrate, failed to reduce cardiovascular events despite significant reductions (~ 25-35%) in triglyceride levels and despite background statin therapy. In contrast, icosapent ethyl, a highly purified omega-3 fatty acid was previously shown to reduce CVD events in hypertriglyceridemic patients, despite more modest reductions (~ 20%) in triglyceride levels in statin treated patients. The divergent results obtained in patients with hypertriglyceridemia (HTG), a group at particularly high risk of CVD, especially when coupled with other risk factors, indicates that triglyceride lowering in of itself is insufficient to offset CVD risk. Rather, the effectiveness of therapy in this high-risk cohort may be the result of the suppression of the inherent atherogenic properties associated with HTG.

Occurrence of metabolic syndrome components in northerners

The metabolic syndrome is currently becoming more common. It is a significant public health concern as it is epidemic affecting populations in many regions of the world. In Magadan region no research has been carried out to study the frequency of components of the metabolic syndrome among northerners. This survey was performed to assess the occurrence of the main and additional components of the metabolic syndrome among 17 to 74 year old residents of the Northern region. Two hundred and forty north born Caucasians participated in the study: male subjects at their young age, working age, and retirement age, all belonging to the territory of Magadan region. We used photometric, immunochemiluminescent research methods, as well as standard methods for assessing body mass index and cardiovascular system. The metabolic syndrome factors were determined in accordance with the criteria of the National Cholesterol Education Program (NCEP), the Adult Treatment Program III (ATP III), the International Diabetes Federation (IDF), and the Consensus of International Experts in Cardiology and Endocrinology. We analyzed five main components of the metabolic syndrome (overweight, carbohydrate metabolic impairments hypertension, hypertriglyceridemia, hypoalphacholesterolemia) and three additional components (presence of insulin resistance, purine metabolism disorder, deficient and insufficient concentrations of vitamin D). Combinations of the components were also studied through the examined age groups. According to the ATP III, NCEP and IDF criteria, the metabolic syndrome was more common in elderly subjects (47%) than in working age (21%) or young examinees (3%). Older males tended to exhibit higher frequency of both the main and additional factors of metabolic syndrome. The total index of the occurrence of metabolic syndrome factors in the group of young men was 101%; in the group of men of working age - 180%, and in men of retirement age - 274%. The results on occurrence of the metabolic syndrome components observed in the surveyed groups of northerners can make an information data base, which we assume can be applied when planning and carrying out scientifically grounded preventive measures, which will improve subjective quality of life and its expectancy under the North conditions.

Predictive performance of lipid parameters in identifying undiagnosed diabetes and prediabetes: a cross-sectional study in eastern China

BACKGROUND

Dyslipidaemia is a risk factor for abnormal blood glucose. However, studies on the predictive values of lipid markers in prediabetes and diabetes simultaneously are limited. This study aimed to assess the associations and predictive abilities of lipid indices and abnormal blood glucose.

METHODS

A sample of 7667 participants without diabetes were enrolled in this cross-sectional study conducted in 2016, and all of them were classified as having normal glucose tolerance (NGT), prediabetes or diabetes. Blood glucose, blood pressure and lipid parameters (triglycerides, TG; total cholesterol, TC; high-density lipoprotein cholesterol, HDL-C; low-density lipoprotein cholesterol, LDL-C; non-high-density lipoprotein cholesterol, non-HDL-C; and triglyceride glucose index, TyG) were evaluated or calculated. Logistic regression models were used to analyse the association between lipids and abnormal blood glucose. The area under the curve (AUC) of the receiver operating characteristic (ROC) curve was used to assess the discriminatory power of lipid parameters for detecting prediabetes or diabetes.

RESULTS

After adjustment for potential confounding factors, the TyG was the strongest marker related to abnormal blood glucose compared to other lipid indices, with odds ratios of 2.111 for prediabetes and 5.423 for diabetes. For prediabetes, the AUCs of the TG, TC, HDL-C, LDL-C, TC/HDL-C, TG/HDL-C, non-HDL-C and TyG indices were 0.605, 0.617, 0.481, 0.615, 0.603, 0.590, 0.626 and 0.660, respectively, and the cut-off points were 1.34, 4.59, 1.42, 2.69, 3.39, 1.00, 3.19 and 8.52, respectively. For diabetes, the AUCs of the TG, TC, HDL-C, LDL-C, TC/HDL-C, TG/HDL-C, non-HDL-C and TyG indices were 0.712, 0.679, 0.440, 0.652, 0.686, 0.692, 0.705, and 0.827, respectively, and the cut-off points were 1.35, 4.68, 1.42, 2.61, 3.44, 0.98, 3.13 and 8.80, respectively.

CONCLUSIONS

The TyG, TG and non-HDL-C, especially TyG, are accessible biomarkers for screening individuals with undiagnosed diabetes.

Age-related blood biochemical changes (lipid metabolism) in healthy young and mature men living under the North conditions

Metabolic disorders (dyslipidemias) are currently crucial since they develop cardiovascular diseases. The work was aimed at studying age dynamics and its correlation with severity of dyslipidemia in basic lipid metabolism variables (in different age groups).

MATERIALS AND METHODS

Examinees were Caucasians born and permanently residing in Magadan region: 55 mature men and 147 young men (mean ages were 36.8±0.8 and 18.7±0.8 yr, respectively). Blood serum lipid metabolism was examined by colorimetric and photometric method using AU 680 (Beckman Coulter, USA).

RESULTS

The data of obtained lipidogram showed dependence of rise in all indicators on subjective older age with higher percentage of dyslipidemia and increase in calculated indices reflecting degree of the lipid profile atherogenicity.

CONCLUSION

Overall, the North study revealed a safer lipid profile in group of younger men, while biochemical picture of older residents demonstrated increased values. Lipid atherogenicity is a very alarming factor in developing cardiovascular diseases, and a predictor of risks for metabolic syndrome.

The Oslo Ischaemia Study: cohort profile

PURPOSE

The Oslo Ischaemia Study was designed to investigate the prevalence and predictors of silent coronary disease in Norwegian middle-aged men, specifically validating exercise electrocardiography (ECG) findings compared with angiography. The study has been important in investigating long-term predictors of cardiovascular morbidity and mortality, as well as investigating a broad spectrum of epidemiological and public health perspectives.

PARTICIPANTS

In 1972-1975, 2014 healthy men, 40-59 years old, were enrolled in the study. Comprehensive clinical examination included an ECG-monitored exercise test at baseline and follow-ups. The cohort has been re-examined four times during 20 years. Linkage to health records and national health registries has ensured complete endpoint registration of morbidity until the end of 2006, and cancer and mortality until the end of 2017.

FINDINGS TO DATE

The early study results provided new evidence, as many participants with a positive exercise ECG, but no chest pain ('silent ischaemia'), did not have significant coronary artery stenosis after all. Still, they were over-represented with coronary disease after years of follow-up. Furthermore, participants with the highest physical fitness had lower risk of cardiovascular disease, and the magnitude of blood pressure responses to moderate exercise was shown to influence the risk of cardiovascular disease and mortality. With time, follow-up data allowed the scope of research to expand into other fields of medicine, with the aim of investigating predictors and the importance of lifestyle and risk factors.

FUTURE PLANS

Recently, the Oslo Ischaemia Study has been found worthy, as the first scientific study, to be preserved by The National Archives of Norway. All the study material will be digitised, free to use and accessible for all. In 2030, the Oslo Ischaemia Study will be linked to the Norwegian Cause of Death Registry to obtain complete follow-up to death. Thus, a broad spectrum of additional opportunities opens.

Determinants of Longitudinal Change of Glycated Hemoglobin in a Large Non-Diabetic Population

Although many cross-section studies have assessed the determinants of glycated hemoglobin (HbA_1c), there have been limited studies designed to evaluate the temporal correlates of HbA_1c in non-diabetic patients. This study aimed to identify the major determinants of longitudinal change of HbA_1c in non-diabetic patients. This study included subjects from the 104,451 participants enrolled between 2012 and 2018 in the Taiwan Biobank. We only included participants with complete data at baseline and follow-up (n = 27,209). Patients with diabetes at baseline or follow-up (n = 3983) were excluded. Finally, 23,226 participants without diabetes at baseline and follow-up were selected in this study. △Parameters was defined as the difference between the measurement baseline and follow-up. Multivariable linear regression analysis was used to identify the major determinants of HbA_1c longitudinal change (△HbA_1c). During a mean 3.8 year follow-up, after multivariable analysis, new-onset hypertension (coefficient β: 0.014, p < 0.001), high △heart rate (coefficient β: 0.020, p = 0.002), high △BMI (coefficient β: 0.171, p = 0.028), high △fasting glucose (coefficient β: 0.107, p < 0.001), low △creatinine (coefficient β: −0.042, p < 0.001), high △total cholesterol (coefficient β: 0.040, p < 0.001), high △hemoglobin (coefficient β: 0.062, p < 0.001), high △GPT (coefficient β: 0.041, p = 0.001), and low △albumin (coefficient β: −0.070, p < 0.001) were significantly associated with high △HbA_1c. In non-diabetic population, strategies to decrease the development of new-onset hypertension, resting heart rate, body mass index, fasting glucose, total cholesterol, and GPT and increase serum albumin level might be helpful in slowing the longitudinal change of HbA_1c. In addition, increased hemoglobin and decreased serum creatinine over time also had an impact on the HbA_1c elevation over time in non-diabetic population.

Low-density lipoprotein cholesterol : high-density lipoprotein cholesterol ratio is associated with incident diabetes in Chinese adults: A retrospective cohort study

Aims/Introduction

Dyslipidemia plays a critical role in the pathogenesis of metabolic syndrome and diabetes. Evidence has increasingly shown that the ratio of low‐ to high‐density lipoprotein cholesterol (LDL‐C/HDL‐C) is a novel marker for increased risk of insulin resistance and cardiovascular diseases. However, the correlation between the LDL‐C/HDL‐C ratio and diabetes risk is rarely reported. This is the first study to investigate the association between the LDL‐C/HDL‐C ratio and new‐onset diabetes in a large community‐based cohort.

Materials and Methods

In this retrospective cohort study, a total of 116,661 adults without baseline diabetes were enrolled. Participants were stratified into four groups based on LDL‐C/HDL‐C ratio quartiles. The outcome of interest was new‐onset diabetes.

Results

During a median follow‐up period of 2.98 years, 2,681 (2.3%) new diabetes cases were recorded. The total cumulative incidence of diabetes progressively increased alongside LDL‐C/HDL‐C ratio quartiles (0.31, 0.43, 0.68 and 0.88%, respectively, P‐value for trend <0.001). After adjusting for potential confounders, using the lowest quartile of the LDL‐C/HDL‐C ratio as the reference, the risk of diabetes increased with LDL‐C/HDL‐C ratio quartiles (P‐value for trend <0.001); in particular, from the second to fourth quartile, hazard ratios were 1.18 (95% confidence interval 0.87–1.59), 1.42 (95% confidence interval 1.07–1.90) and 1.92 (95% confidence interval 1.43–2.59), respectively. The results were also robust to challenges in multiple sensitivity analyses.

Conclusions

Among the Chinese population, elevated LDL‐C/HDL‐C ratio might be an independent risk factor for new‐onset diabetes.

Cardiorespiratory fitness, muscular strength and risk of type 2 diabetes: a systematic review and meta-analysis

AIMS/HYPOTHESIS

The study aimed to quantitatively summarise the dose-response relationships between cardiorespiratory fitness and muscular strength on the one hand and risk of type 2 diabetes on the other and estimate the hypothetical benefits associated with population-wide changes in the distribution of fitness.

METHODS

We performed a systematic review with meta-analysis. The PubMed and EMBASE electronic databases were searched from inception dates to 12 December 2018 for cohort studies examining the association of cardiorespiratory fitness or muscular strength with risk of incident type 2 diabetes in adults. The quality of included studies was evaluated using the Newcastle-Ottawa Scale.

RESULTS

Twenty-two studies of cardiorespiratory fitness and 13 studies of muscular strength were included in the systematic review with both exposures having ten estimates available for the primary adiposity- or body size-controlled meta-analysis. In random-effects meta-analysis including 40,286 incident cases of type 2 diabetes in 1,601,490 participants, each 1 metabolic equivalent (MET) higher cardiorespiratory fitness was associated with an 8% (95% CI 6%, 10%) lower RR of type 2 diabetes. The association was linear throughout the examined spectrum of cardiorespiratory fitness. In 39,233 cases and 1,713,468 participants each 1 SD higher muscular strength was associated with a 13% (95% CI 6%, 19%) lower RR of type 2 diabetes. We estimated that 4% to 21% of new annual cases of type 2 diabetes among 45-64-year-olds could be prevented by feasible and plausible population cardiorespiratory fitness changes.

CONCLUSIONS/INTERPRETATION

Relatively small increments in cardiorespiratory fitness and muscle strength were associated with clinically meaningful reductions in type 2 diabetes risk with indication of a linear dose-response relationship for cardiorespiratory fitness.

REGISTRATION

PROSPERO (CRD42017064526).

Contribution and interaction of the low-density lipoprotein cholesterol to high-density lipoprotein cholesterol ratio and triglyceride to diabetes in hypertensive patients: A cross-sectional study

AIMS/INTRODUCTION

Hypertension is one of the most significant risk factors for diabetes. The present study aimed to investigate the associations of lipid profiles, including the ratio of low-density lipoprotein cholesterol (LDL-C)-to-high-density lipoprotein cholesterol (HDL-C) and triglyceride (TG) levels, as well as their interactions, with type 2 diabetes in hypertensive patients.

MATERIALS AND METHODS

Hypertensive patients without a history of diabetes and hypolipidemic agents were enrolled continuously at the Hypertension Clinic, Zhongshan Hospital, Fudan University (Shanghai, China) from 2014 to 2016. General clinical data, including body mass index, blood pressure, fasting glucose and 2-h post-load glucose levels, and lipid profiles, were collected. The LDL-C/HDL-C ratio, TG/HDL-C ratio and TC/HDL-C ratio were separately calculated. Statistical analyses were carried out by using SPSS software (version 13.0).

RESULTS

In total, 935 hypertensive patients were included, of which 114 patients (12.2%) were diagnosed with diabetes. After multivariate adjustments, the LDL-C/HDL-C ratio and TG levels had the most significant and independent associations with diabetes. In the multivariate logistic regression, the LDL-C/HDL-C ratio and TG were independently associated with diabetes. After the interaction variable was included, the LDL-C/HDL-C ratio remained independently associated with diabetes, but TG was replaced by TG*LDL-C/HDL-C.

CONCLUSIONS

In conclusion, elevated LDL-C/HDL-C ratios and TG levels were associated with diabetes in patients with hypertension, with an interactive effect of the LDL-C/HDL-C ratio and TG on diabetes in the hypertensive population.

Impact of 3-year changes in lipid parameters and their ratios on incident type 2 diabetes: Tehran lipid and glucose study

BACKGROUND

To examine the impact of changes in all lipid measures including total cholesterol (TC), log-transformed triglycerides (Ln-TG), high density lipoprotein cholesterol (HDL-C), low density lipoprotein cholesterol (LDL-C), non-HDL-C, TC/HDL-C and Ln TG/HDL-C, over an approximate 3 year duration, on incident type 2 diabetes (T2DM).

METHODS

A total of 5474 participants, mean age 41.3 years, without prevalent diabetes at baseline or the first follow-up were entered into the study. The association of lipid changes between baseline and the first follow-up i.e., between 1999-2002 and 2002-2005 for those entered in the first phase (n = 4406) and between 2002-2005 and 2005-2008 for participants recruited in the second phase (n = 1068) with incident T2DM over the follow-up period was assessed, using multivariate Cox proportional hazard analysis.

RESULTS

During a median follow-up of 8.9 years after the second lipid measurements, 577 incident cases of T2DM occurred. After adjustment for a wide variety of confounders and body mass index (BMI) change, each 1-SD increase in TC, Ln-TG, HDL-C, LDL-C, non-HDL-C, Ln-TG/HDL-C and TC/HDL-C was associated with 12, 14, 0.86, 12, 16, 15 and 13% risk for T2DM, respectively (all p-values < 0.05). However, after further adjustment for fasting plasma glucose (FPG) change, the risk disappeared for all lipid measures, excluding HDL-C [hazard ratio (HR): 0.84 (0.76-0.93)], Ln-TG/HDL-C [1.14 (1.04-1.25)] and TC/HDL-C [1.12 (1.04-1.21)].

CONCLUSIONS

Three year changes in all lipid parameters, after adjustment for known risk factors of T2DM and BMI changes, were associated with incident T2DM. The independent risk of HDL-C and its ratios remained even after adjustment for FPG changes.

The role of glycaemic and lipid risk factors in mediating the effect of BMI on coronary heart disease: a two-step, two-sample Mendelian randomisation study

AIMS/HYPOTHESIS

The extent to which effects of BMI on CHD are mediated by glycaemic and lipid risk factors is unclear. In this study we examined the effects of these traits using genetic evidence.

METHODS

We used two-sample Mendelian randomisation to determine: (1) the causal effect of BMI on CHD (60,801 case vs 123,504 control participants), type 2 diabetes (34,840 case vs 114,981 control participants), fasting glucose (n = 46,186), insulin (n = 38,238), HbA_1c (n = 46,368) and LDL-cholesterol, HDL-cholesterol and triacylglycerols (n = 188,577); (2) the causal effects of glycaemic and lipids traits on CHD; and (3) the extent to which these traits mediate any effect of BMI on CHD.

RESULTS

One SD higher BMI (~ 4.5 kg/m²) was associated with higher risk of CHD (OR 1.45 [95% CI 1.27, 1.66]) and type 2 diabetes (1.96 [95% CI 1.35, 2.83]), higher levels of fasting glucose (0.07 mmol/l [95% CI 0.03, 0.11]), HbA_1c (0.05% [95% CI 0.01, 0.08]), fasting insulin (0.18 log pmol/l [95% CI 0.14, 0.22]) and triacylglycerols (0.20 SD [95% CI 0.14, 0.26]) and lower levels of HDL-cholesterol (-0.23 SD [95% CI -0.32, -0.15]). There was no evidence for a causal relation between BMI and LDL-cholesterol. The causal associations of higher triacylglycerols, HbA_1c and diabetes risk with CHD risk remained after performing sensitivity analyses that considered different models of horizontal pleiotropy. The BMI-CHD effect reduced from 1.45 to 1.16 (95% CI 0.99, 1.36) and to 1.36 (95% CI 1.19, 1.57) with genetic adjustment for triacylglycerols or HbA_1c, respectively, and to 1.09 (95% CI 0.94, 1.27) with adjustment for both.

CONCLUSIONS/INTERPRETATION

Increased triacylglycerol levels and poor glycaemic control appear to mediate much of the effect of BMI on CHD.

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.