Trend of HDL increase among Japanese people continues in National Health and Nutrition Survey

Continuous and Marked Increase of Japanese HDL Associates Paradoxically with their Nutritional Shift

AIMS

Plasma HDL has evidently increased for decades among Japanese, exclusively in HDL particles containing apoA-I but not A-II. Its metabolic background is yet to be elucidated.

METHODS

Trends in plasma lipoproteins were analyzed by examining data on total cholesterol, triglyceride and HDL-cholesterol, which are available in the public database of the National Health and Nutrition Examination Survey of Japan (NHNESJ) and in the clinical data of SRL Co., from 1989 to 2019, estimating cholesterol (C) in non-HDL, VLDL, LDL, and sub-fractions of LDL using the equations by Sampson et al. Food intake and supply data in NHNSJ and in the UN Food and Agriculture Organization were also analyzed in relation to the lipoprotein analysis.

RESULTS

HDL-C levels showed a steady increase in men and women throughout the period as per the data retrieved in NHNSJ and SRL data. It is noted to be higher in women than men (from 46.8 to 52.7, and from 58.4 to 68.3 in mg/dl, respectively). Triglyceride and VLDL-C were higher in men but sex difference was not apparent in non-HDL-C and LDL-C levels, while these parameters slightly decreased in both sexes. The increase in HDL was most prominent in women in the age of 50 - 59 (from 57.0 to 73.4). The age-dependent HDL trend was reversed among women during the study period, as increasing instead of decreasing. This increase in HDL was found to coincide with lowered fish/meat ratio in food intake among Japanese.

CONCLUSION

Marked increase in plasma HDL among Japanese is age- and sex-dependent and exhibited an apparent paradoxical association with lowered fish/meat ratio in their diet. Further investigation is required to elucidate the background for these findings.

Non-High-Density Lipoprotein Cholesterol and Risk of Cardiovascular Disease: The Japan Epidemiology Collaboration on Occupational Health Study

AIMS

We aimed to investigate the association between non-high-density lipoprotein cholesterol (non-HDL-C) levels and the risk of cardiovascular disease (CVD) and its subtypes.

METHODS

In this contemporary cohort study, we analyzed the data of 63,814 Japanese employees aged ≥ 30 years, without known CVD in 2012 and who were followed up for up to 8 years. The non-HDL-C level was divided into 5 groups: ＜110, 110-129, 130-149, 150-169, and ≥ 170 mg/dL. The Cox proportional hazards model was used to calculate the hazard ratios (HRs) and the corresponding 95% confidence intervals (CIs) for CVD and its subtypes associated with each non-HDL-C group, considering 130-149 mg/dL as the reference group.

RESULTS

During the study period, 271 participants developed CVD, including 78 myocardial infarctions and 193 strokes (102 ischemic strokes, 89 hemorrhagic strokes, and 2 unknowns). A U-shaped association between non-HDL-C and stroke was observed. In the analysis of stroke subtypes, the multivariable-adjusted HR (95% CI) for hemorrhagic stroke was 2.61 (1.19-5.72), 2.02 (0.95-4.29), 2.10 (1.01-4.36), and 1.98 (0.96-4.08), while that for ischemic stroke was 1.54 (0.77-3.07), 0.91 (0.46-1.80), 0.73 (0.38-1.41), and 1.50 (0.87-2.56) in the ＜110, 110-129, 150-169, and ≥ 170 mg/dL groups, respectively. Individuals with elevated non-HDL-C levels had a higher risk of myocardial infarction.

CONCLUSIONS

High non-HDL-C levels were associated with an increased risk of myocardial infarction. Moreover, high and low non-HDL-C levels were associated with a high risk of stroke and its subtypes among Japanese workers.

Global epidemiology of dyslipidaemias

Dyslipidaemias are alterations to the plasma lipid profile that are often associated with clinical conditions. Dyslipidaemias, particularly elevated plasma LDL-cholesterol levels, are major risk factors for cardiovascular disease, but some forms, such as hypertriglyceridaemia, are associated with severe diseases in other organ systems, including non-alcoholic fatty liver disease and acute pancreatitis. Dyslipidaemias can be genetically determined (primary or familial dyslipidaemias) or secondary to other conditions (such as diabetes mellitus, obesity or an unhealthy lifestyle), the latter being more common. Hypercholesterolaemia is the most common form of dyslipidaemia and is associated with an increased risk of cardiovascular disease, with elevated plasma LDL-cholesterol levels being the 15th leading risk factor for death in 1990, rising to 11th in 2007 and 8th in 2019. The global burden of dyslipidaemias has increased over the past 30 years. Furthermore, the combination of high triglyceride levels and low HDL-cholesterol levels (together with the presence of small, dense LDL particles), referred to as atherogenic dyslipidaemia, is highly prevalent in patients with diabetes or metabolic syndrome and increases their risk of cardiovascular disease. Given the increasing prevalence of diabetes worldwide, treating lipid abnormalities in these patients might reduce their risk of cardiovascular disease.

Temporal Trends in Atherosclerotic Risk Factors in School Children - Findings From 20-Year Surveillance

BACKGROUND

Although it has been discussed which measures against atherosclerotic diseases should be started in childhood, the current situation in Japan is unclear.

METHODS AND RESULTS

We conducted a health management survey of all 12-year-old children in a local town for 20 years. The body mass index tended to decrease over time. Although the serum low-density lipoprotein cholesterol level did not change, the levels of serum high-density lipoprotein cholesterol and serum triglycerides significantly increased over time.

CONCLUSIONS

The serum triglyceride levels in school children increased significantly, probably through lifestyle changes, and the health management system should be reviewed.

Secular Trends in Lipid Profiles in Korean Adults Based on the 2005-2015 KNHANES

Dyslipidemia is a primary, critical risk factor for cardiovascular disease. Therefore, evaluating the trends in lipid profiles is crucial for the development of health policies and programs. We studied trends in lipid profiles in Korean adults over an 11-year period according to the use of lipid-lowering medications through age-specific analysis. A total of 73,890 participants were included in the Korean National Health and Nutrition Examination Survey III (2005)-VI (2013–2015). The proportion of participants on lipid-lowering medications has increased. This trend was apparent in age groups of over 40 years in both men and women. Lipid-lowering medications successfully reduced mean total cholesterol (TC), but there was no favorable trend in TC in participants not taking lipid-lowering medication in both men and women. Unlike men, triglyceride and non-high-density lipoprotein cholesterol (HDL) decreased in women without lipid-lowering medications. In age-specific hypercholesterolemia, the prevalence of hypercholesterolemia significantly increased in the age groups of 30–59 and 30–49 years in men and women without lipid-lowering medications, respectively. Meanwhile, mean HDL-C levels increased over the 11-year period regardless of lipid-lowering drug use in both men and women. These analyses identified an upward trend in TC and HDL-C over the 11-year period.