Fish and coronary artery disease

Pre-Hypertension among Young Adults (20-30 Years) in Coastal Villages of Udupi District in Southern India: An Alarming Scenario

Introduction

According to Joint National Committee-7 (JNC-7) guidelines, a systolic blood pressure (SBP) of 120 to 139 mm Hg and/or diastolic blood pressure (DBP) of 80 to 89 mm Hg is considered as pre-hypertension. Existing evidence suggest that the cardiovascular morbidities are increasing among pre-hypertensive individuals compared to normal.

Objective

To assess the magnitude and factors associated with pre-hypertension among young adults (20–30 years) in coastal villages of Udupi Taluk (an area of land with a city or town that serves as its administrative centre and usually a number of villages), Udupi District, Karnataka state, India.

Design

Community based cross sectional study

Setting

6 (out of total 14) coastal villages of Udupi Taluk, Karnataka state, India.

Sample

1,152 young adults (age group: 20–30 years) selected by stratified random sampling in 6 coastal villages of Udupi Taluk, Karnataka state, India

Method

A semi structured pre-tested questionnaire was used to elicit the details on socio-demographic variables, dietary habits, tobacco use, alcohol consumption, physical activity, family history of hypertension and stress levels. Anthropometric measurements and blood pressure were recorded according to standard protocols. Serum cholesterol was measured in a sub sample of the study population. Multivariate logistic regression was applied to identify the independent correlates of pre-hypertension among young adults (20–30 years).

Main Outcome Measures

Prevalence, Odds ratio (OR) and adjusted (adj) OR for pre-hypertension among young adults (20–30 years).

Results

The prevalence of pre-hypertension in the study population was 45.2% (95%CI: 42.4–48). Multivariate logistic regression analysis revealed that age group of 25–30 years (adj OR: 4.25, 95% CI: 2.99–6.05), white collared (adj OR: 2.29, 95% CI: 1.08–4.85) and skilled occupation (adj OR: 3.24, 95% CI: 1.64–6.42), students (adj OR: 2.46, 95% CI: 1.22–4.95), using refined cooking oil (adj OR: 0.53, 95% CI: 0.29–0.95), extra salt in meals (adj OR: 2.46, 95% CI: 1.52–3.99), salty food items (adj OR: 6.99, 95% CI: 3.63–13.48), pre-obese (adj OR: 1.66, 95% CI: 1.03–2.67) and obese (adj OR: 9.16, 95% CI: 2.54, 36.4) were the significant correlates of pre-hypertension.

Conclusion

In the study population, prevalence of pre-hypertension among young adults (20–30 years) was high (45.2%). Biological (age 25–30 years, pre-obesity and obesity) and behavioral (sedentary occupation, intake of extra salt in meals/salty food and not using refined cooking oil) factors were associated with pre-hypertension. Study emphasizes the need of community based screening of pre-hypertension under National Rural Health Mission. It also provides apt information for the evidence based designing of interventions for lifestyle modifications among high risk young adults in the study area.

The role of eggs, margarines and fish oils in the nutritional management of coronary artery disease and strokes

Although egg yolk is a rich source of cholesterol, the effect of eggs in raising serum cholesterol is variable and in some subjects there is no effect whatsoever. However, oxidized cholesterol can increase atherosclerosis even with normal serum cholesterol. In order to attenuate oxidation of cholesterol in eggs, it is necessary to limit the degree of heat applied. This means that we should use only soft-boiled eggs which should be almost like water. We can also avoid egg yolk altogether and get a highly nutritious egg food from the egg white alone. The saturated fats from milk products, especially butter, are highly atherogenic. There are available many butter substitutes in the form of margarines. But many of these margarines have hydrogenated vegetable oils which result in the production of trans-fatty acids. The trans-fatty acids are as atherogenic as saturated fats. There are available, however, margarines without the trans-fatty acids. These are found only in large supermarkets. Fish oils contain N3 fatty-acids which, unlike vegetable oils which contain N6 fatty-acids, can prevent atherosclerosis and sudden death by counteracting ventricular arrhythmias, acting as antioxidants, antithrombotic, anti-inflammatory agents, and decreasing triglycerides and blood pressure.

Relationship between dental caries and risk factors for atherosclerosis in Swedish adolescents?

In an earlier study on a selected group of adolescents with high caries prevalence we found dietary habits that resembled those considered to promote the development of atherosclerosis. In the present study we have compared DMF-score with factors traditionally associated with the risk for development cardiovascular diseases (CVD). All 15-yr-olds living in an urban community in Northern Sweden 1987-1989 were included. Medical variables related to the risk of developing CVD were evaluated in groups of adolescents with various levels of manifest caries expressed as decayed and filled surfaces (DFS). The proportion of individuals with no medical risk factor at an unfavorable level was significantly higher in a caries free than in a high-caries (DFS > or = 9) group. Adolescents with two or more medical factors reaching unfavorable levels had a significantly higher caries score than the group with no factor at unfavorable level. A significant positive correlation was found for the whole group between DFS-score and relative body weight (body mass index) in an univariate correlation test as well as multiple linear regression analysis. The hypothesis that high caries score can be an indicator for unfavorable levels of traditional risk factors for CVD is not contradicted by the results in the present study but supported by the observed covariation with BMI. We therefore suggest that dietary counseling to adolescents with a high caries score in combination with a moderate obesity can be of advantage in reducing the caries risk as well as the risk for development of CVD at higher ages.

Long-term diet modification and platelet activity

Platelet activity was assessed in a sub-sample of 56 participants in the MRC Diet and Reinfarction Trial (DART). Men whose diets contained a high ratio of polyunsaturated to saturated fatty acids (a P:S ratio of greater than 0.5) showed reduced secondary platelet aggregation to adenosine diphosphate (ADP) in platelet-rich plasma (PRP), and diminished platelet aggregation to ADP in whole blood. A trend of reduced secondary platelet aggregation to ADP with increasing dietary eicosapentaenoic acid was noted, but this was not statistically significant. The results of this study and the MRC Diet and Reinfarction Trial suggest a mediatory role for platelet activity in the relationship between diet and ischaemic heart disease.

Dietary change and coronary heart disease

Dietary changes a hundred years ago in Europe, America and Australia were needed to feed their growing industrial populations. By 1909 margarines were first made by the hydrogenation of marine oils and, later, vegetable oils as a substitute for butter, thereby introducing saturated fats. The demise of the highly nutritious herring and its oil's hydrogenation into margarines seems to have coincided with a big increase in coronary heart disease (CHD). The Japanese escaped such changes to their rice diet by the influence of the inevitable annual monsoon while southern Europe's CHD immunity may hinge on its permanent olive oil and vitamin C antioxidant staples. Britain's 'angina pectoris' probably arose following the enclosures which changed arable (strip) into animal farming in the middle ages but cases rose only slowly from Heberden's 100 in 1802 to McKenzie's 200 by 1923. It seems likely, therefore, that much of the sudden increase to 2000 reported by Maurice Cassidy in 1945, despite the impact of this century's increased longevity on CHD, will be due to dietary change together with smoking's increasing impact.

Fish oil: a panacea?

Since the first report by Bang and Dyerberg regarding the apparent beneficial effects of a fish oil-enriched diet on the incidence of atherosclerotic heart disease in Greenland eskimos, a considerable number of studies have been performed regarding the effects of omega-3 polyunsaturated fatty acids on the prevention and treatment of a variety of disease states not necessarily related to atherosclerosis. Studies have been performed on healthy volunteers and in patients with hyperlipidaemia, atherosclerotic vascular disease, diabetes, asthma, psoriasis and chronic renal insufficiency, amongst others. Positive effects on platelet activity, lipid profile, blood rheology and blood pressure--all factors which are presumably of importance in the pathogenesis of atherosclerotic disease have been noted in these studies, albeit with a wide range of variability. Some negative effects also appear to exist. However, some general conclusions can be made regarding the effects of a fish oil-enriched diet.

Plasma fibrinogen and coronary risk factors: the Scottish Heart Health Study

Plasma fibrinogen was measured in a sample of 8824 men and women aged 40-59 years participating in the Scottish Heart Health Study, and related to cardiovascular risk factors. Women had higher fibrinogen levels than men. In both sexes, multivariate analysis showed that fibrinogen was positively associated with age, smoking, total cholesterol and body mass index and negatively associated with alcohol consumption. Among women, early menopause and systolic blood pressure were also associated with fibrinogen levels. Univariate analyses showed weak positive associations with fish consumption for both sexes although only male white fish consumption entered the final model. Women with a history of contraceptive pill usage had significantly lower fibrinogen levels. The relationship between fibrinogen and physical activity was complex, and could largely be explained by smoking. These findings support the hypothesis that raised fibrinogen is one mechanism by which several major risk factors may promote coronary heart disease. However, known risk factors explained, at most, 10% of the total variance in fibrinogen levels among the general population.

Effects of Maxepa on serum lipids in hypercholesterolaemic subjects

The effect of dietary supplementation with 20 capsules/day Maxepa or olive oil on serum lipids has been studied in 21 hypercholesterolaemic patients using a double-blind crossover design. Platelet membrane eicosapentaenoic acid percentage rose by more than 10-fold after 2 months dietary supplementation with Maxepa. Total serum cholesterol was unchanged and there was a rise in LDL-cholesterol and HDL-cholesterol concentration in men, but no change in LDL-cholesterol, and a fall in HDL-cholesterol in women. In men and women there was a marked fall in total serum triglyceride, VLDL-triglyceride and VLDL-cholesterol levels. Thus, Maxepa is not an effective treatment for isolated hypercholesterolaemia.