Dietary and serum magnesium levels in patients with acute myocardial infarction, coronary artery disease and noncardiac diagnoses

OBJECTIVE

To study the relation of dietary and serum levels of magnesium (Mg) in acute myocardial infarction (AMI) and its complications in relation to noncardiac diagnoses.

METHODOLOGY

Case control study in a primary and secondary care center for AMI patients. The study included 460 subjects with definite AMI (n = 335, group A), possible AMI (n = 64, group B), unstable angina (n = 19, group C) and controls with noncardiac chest pain (n = 42, group D). Demographic variables, dietary intake, and clinical and biochemical data were compared. Mean age, sex, body weight, and body mass index were comparable in all the groups.

RESULTS

Dietary fat and cholesterol intakes were significantly higher and carbohydrate intakes were lower in group A, B and C patients with coronary artery disease compared to control group D. Dietary consumption of Mg was comparable in all groups; however, in 85 patients in group A (272.5 mg/day) and 17 in group B (280.4 mg/day) in whom ventricular arrhythmias were present, Mg intake was relatively lower compared to control group D (316.6 mg/day). Serum Mg levels in group A (1.66 mEq/L), B (1.65 mEq/L), and C (1.66 mEq/L) were within normal (1.74 mEq/L) limits, but were significantly lower than in control group D.

CONCLUSIONS

Lower serum Mg in group A, B and C patients was attributed to increased demand during AMI, although in patients with complications (ventricular arrhythmias), Mg deficiency may in part result from relatively lower Mg intake, a hypothesis which requires further study.

Neonatal mortality in Meerut district

A study of neonatal mortality in Meerut district revealed an infant mortality rate of 50.1 per 1000 live births. Neonatal mortality accounted for 37.8% of infant mortality with a neonatal mortality rate of 19.0 per 1000 live births. 90.5% of these neonates were delivered at home largely by untrained personnel (57.2%). Only 28.6% of these neonates were treated by qualified doctors and only 30.9% of their mothers were fully immunized against tetanus. At least 2/3rd of neonatal mortality was due to exogenous factors with tetanus neonatorum and septicaemia being the principal causes of mortality each accounting for a mortality rate of 4.7 per 1000 live births.

Effects of diet and lifestyle changes on atherosclerotic risk factors after 24 weeks on the Indian Diet Heart Study

In a randomized, single-blind, controlled trial, 621 patients were assigned either intervention diet A (group A, 310 patients) or control diet B (group B, 311 patients) for a period of 24 weeks. After 24 weeks as revealed by dietary questionnaires, group A patients received: (1) a diet with a higher percentage of calories from fruits and vegetables and complex carbohydrates; (2) a higher polyunsaturated/saturated fat ratio diet; and (3) a larger amount of soluble dietary fiber, antioxidant vitamins and minerals and low saturated fat and cholesterol than group B. Group A patients also did more physical and yogic exercises than group B. Adherence to diet and exercise was obtained through questionnaires and information obtained was quantified into a formula. After 24 weeks, the overall score of diet and exercises was significantly higher in group A than in group B. There was a significant decrease in serum total cholesterol (13.3%), low-density lipoprotein cholesterol (16.9%), triglycerides (19.2%), fasting blood glucose (19.5%) and blood pressures (11.5/6.2 mm Hg) in the intervention group compared with initial levels and changes in group B. The effect of exercise on the decrease in risk factors was additive. Within group A, overall score for diet and exercise was greater in 1 subset of 116 patients in the intervention group which had maximal lifestyle changes. A separate analysis of data in this subgroup revealed a greater decrease in risk factors compared with risk factor changes in the remaining 194 patients with less higher overall score; this indicated that the relation of lifestyle changes with reduction in risk factors may be of causal nature.(ABSTRACT TRUNCATED AT 250 WORDS)

Effect on mortality and reinfarction of adding fruits and vegetables to a prudent diet in the Indian experiment of infarct survival (IEIS)

The effects of antioxidant-rich foods as adjuncts to a prudent diet were compared for 12 weeks in a randomized, single-blind and controlled trial in 204 (group A) and 202 (group B) patients with acute myocardial infarction. There was a significant decrease in cardiac end points in group A compared to group B (37 vs 58, p < 0.01) after 12 weeks. Within intervention group A, those 108 patients with greater adherence to the intervention program showed a greater reduction in cardiac end points (14 vs 58, p < 0.001), and a significant decrease in total mortality (6 vs 28, p < 0.001), including cardiac mortality (6 vs 25, p < 0.01) compared to group B. Underlying these beneficial effects, antioxidant-rich foods caused a significantly smaller rise in lactate dehydrogenase (LDH) cardiac enzyme in group A than in group B (427.8 vs 561.6 IU/dL), indicating that the protective influence of such a diet may be observed within 1 week. The subset of group A patients showing reduction in mortality also had a lesser rise in LDH and greater reduction in blood lipids, blood glucose and blood pressures. Antioxidant-rich foods also caused a significant decrease in blood lipids with a lower decrease in high-density lipoprotein cholesterol in group A than in group B. Assay of serum level of antioxidants and long-term follow-up may confirm our observations.

Socioeconomic factors and prevalence of endemic goitre

The present study was conducted on 2611 school children of a rural area of Meerut, with the objectives to find out the prevalence and distribution of endemic goitre and the socioeconomic variables associated with the distribution of the endemic goitre. Grading of goitre was done as per the criteria laid down by the WHO-1979 (1). The overall prevalence rate of endemic goitre was 50.1%, the prevalence was more among females (55.1%) as compared to males (47.2%). Maximum number of goitre cases were having grade Ia enlargement (46.9%) followed by grade Ib (34.1%), grade 2(15.0%) and grade 3 (4.0%). Prevalence increased with increase in age. Statistically significant differences were found in the prevalence of endemic goitre in relation to different religions and caste groups, different occupations of the parents/guardians of children and types of houses used for the purpose of living.

Can guava fruit intake decrease blood pressure and blood lipids?

A randomized, single-blind, controlled trial was conducted to examine the effects of guava fruit intake on BPs and blood lipids in patients with essential hypertension. Of 145 hypertensives that entered the trial, 72 patients were assigned to take a soluble fibre and a potassium-rich diet containing 0.5-1.0 kg of guava daily (group A) and 73 patients to their usual diet (group B), while salt, fat, cholesterol, caffeine and alcohol intake were similar in both groups. Mean age, mean body weight and male sex, were similar, and so were risk factors, mean BPs, mean serum sodium, potassium, calcium, magnesium, triglycerides, cholesterol and HDL-cholesterol in both groups. Dietary adherence to guava intake was checked by a questionnaire. After four weeks of follow-up on an increased consumption of dietary potassium and low sodium/potassium ratio, group A patients were associated with 7.5/8.5 mmHg net decrease in mean systolic and diastolic pressures compared with group B. Increased intake of soluble dietary fibre (47.8 +/- 11.5 vs. 9.5 +/- 0.85 g/day) was associated with a significant decrease in serum total cholesterol (7.9%), triglycerides (7.0%) and an insignificant increase in HDL-cholesterol (4.6%) with a mild increase in the ratio of total cholesterol/HDL-cholesterol in group A patients compared with group B. It is possible that an increased consumption of guava fruit can cause a substantial reduction in BPs and blood lipids with a lack of decrease in HDL-cholesterol due to its higher potassium and soluble fibre content, respectively.

Risk factors for coronary heart disease: synthesis of a new hypothesis through adaptation

A risk factor is a characteristic which is associated with a greater than average probability of developing coronary disease. Raised serum cholesterol and hypertension are two such factors. Intervention studies conducted to confirm the risk factor hypothesis have shown that reduction of serum cholesterol and essential hypertension may be associated with a small decreased CHD incidence, however there were almost as many deaths due to coronary disease in the intervention groups as in the control groups. These findings suggest that our approach to risk factor intervention may be a misguided attempt which needs modification. It is possible that the major risk factors develop in an attempt of our body to adapt to environmental factors such as increased intake of salt, saturated fat and cholesterol, physical inactivity, increased intake of calories and obesity and stress. Smoking may be the result of social changes. Since the body has to modify its metabolic mechanism depending upon the factor to which it adapts, development of hyperlipidemia and hypertension may be protective mechanisms of the body which it has developed while fighting against environmental factors. Reduction of major risk factors by drug therapy may mean that we are trying to prevent the body, fighting environmental factors. Thus our approach to control of the major risk factors should be to treat the causative environmental factors or alter the lifestyle.(ABSTRACT TRUNCATED AT 250 WORDS)

Effects of guava intake on serum total and high-density lipoprotein cholesterol levels and on systemic blood pressure

There is evidence that inclusion of high fiber foods such as oats, fruits and vegetables in the diet can decrease fat intake and modulate blood lipids. To test this hypothesis, 61 group A and 59 group B patients with essential hypertension were administered guava fruit preferably before meals in a foods-to-eat approach rather than foods-to-restrict, in a randomized and single-blind fashion for 12 weeks. At entry into the study, mean age, male sex, mean body mass index, percentages of risk factors and mean levels of blood lipids were comparable between groups A and B. Adherence to guava consumption was assessed by questionnaires and weighing of guava intake by 24-hour recall after 12 weeks of follow-up. Nutrient intakes including saturated and total fat were significantly decreased; carbohydrates, total and soluble fiber and vitamins and mineral intakes were significantly higher in group A than in group B at 12 weeks. There was a significant net decrease in serum total cholesterol (9.9%), triglycerides (7.7%) and blood pressures (9.0/8.0 mm Hg) with a significant net increase in high-density lipoprotein cholesterol (8.0%) after 12 weeks of guava fruit substitution in group A than in group B. By adding moderate amounts of guava fruit in the usual diet, changes in dietary fatty acids and carbohydrates may occur, providing significant amounts of soluble dietary fiber and antioxidant vitamins and minerals without any adverse effects. There is a greater decrease in lipoprotein metabolism and blood pressures.

Effect of fat-modified and fruit- and vegetable-enriched diets on blood lipids in the Indian Diet Heart Study

This study was designed to test the efficacy of the administration of fruits and vegetables for 12 weeks as an adjunct to a prudent diet in decreasing blood lipids in 310 (intervention; group A) and 311 (control; group B) patients with risk factors of coronary artery disease (CAD) in a parallel, single-blind fashion. At entry to the study, sex, mean age, body weight, body mass index, systolic and diastolic blood pressures, and blood lipoproteins were comparable between both groups. Tasty fruits and vegetables were given to patients to eat before major meals for better nutrient adherence and adequacy. Dietary intakes were determined by questionnaires and by weighing of fruit and vegetable intake. Fruits and vegetables decreased total cholesterol level by 6.5% and low-density lipoprotein cholesterol level by 7.3% in group A, whereas the levels were unchanged in group B. The high-density lipoprotein cholesterol levels that decreased during the diet stabilization period in both groups, increased by 5.6% in group A after 12 weeks. Serum triglycerides also decreased (7%) more in group A than B. Fasting blood glucose decreased by 6.9% in group A and by 2.6% in group B. The combined effect of a fat-modified diet plus fruits and vegetables was greater than these changes. Because tasty fruits were taken by the patients before meals (when they are hungry) and are easily available at reasonable cost in our marketing and buying capacity, the compliance was excellent.(ABSTRACT TRUNCATED AT 250 WORDS)

Nutritional modulators of lipoprotein metabolism in patients with risk factors for coronary heart disease: diet and moderate exercise trial

To study the role of diet as a risk factor for coronary heart disease (CHD), 463 adults (25-65 years, 419 males) at risk of or with CHD were assigned to group A (n = 231) receiving a cardiovasoprotective diet or group B (n = 232) receiving a normal diet in a randomized, single-blind fashion. Age, sex, risk factors and incidence of CHD were comparable between the two groups. Group A received a significantly higher percentage of calories in relation to complex carbohydrates, vegetable proteins, polyunsaturated fatty acids, and had a higher polyunsaturated:saturated fatty acid (P:S) ratio compared to control group B, which received more saturated fat and cholesterol. Group A also received more soluble dietary fiber and magnesium (Mg) and was physically more active than group B. Exercise and dietary adherence were tested by a questionnaire. After 12 weeks, results indicated a significant decrease in mean serum total cholesterol (9.0 vs 3.1%), low-density-lipoprotein cholesterol (LDL-C) (9.8 vs 3.8%) and triglyceride (11.1 vs 5.4%), and an increase in serum Mg (8.5%) in the intervention group compared to initial levels. No significant changes in mean levels were noted in the control group. Body weight significantly decreased and physical activity was significantly higher in the intervention group compared to the control group during the 12-week followup on similar intakes of energy. There were insignificant changes in high-density-lipoprotein cholesterol (HDL-C) in both groups.(ABSTRACT TRUNCATED AT 250 WORDS)

Randomised controlled trial of cardioprotective diet in patients with recent acute myocardial infarction: results of one year follow up

OBJECTIVE

To test whether a fat reduced diet rich in soluble dietary fibre, antioxidant vitamins, and minerals reduces complications and mortality after acute myocardial infarction.

DESIGN

Randomised, single blind, controlled trial.

SETTING

Primary and secondary care research centre for patients with myocardial infarction.

SUBJECTS

505 patients with suspected acute myocardial infarction. Those with definite or possible acute myocardial infarction and unstable angina based on World Health Organisation criteria were assigned to diet A (n = 204) or diet B (n = 202) within 24-48 hours of infarction.

INTERVENTIONS

Both groups were advised to follow a fat reduced diet. Group A was also advised to eat more fruit, vegetables, nuts, and grain products.

MAIN OUTCOME MEASURES

Mortality from cardiac disease and other causes. Serum lipid concentrations and compliance with diet.

RESULTS

Blood lipoprotein concentrations and body weight fell significantly in patients in group A compared with those in group B (cholesterol fell by 0.74 mmol/l in group A v 0.32 mmol/l in group B, 95% confidence interval of difference 0.14 to 0.70, and weight by 7.1 v 3.0 kg, 0.52 to 7.68). The incidence of cardiac events was significantly lower in group A than group B (50 v 82 patients, p less than 0.001). Group A also had lower total mortality (21 v 38 died, p less than 0.01) than group B.

CONCLUSIONS

Comprehensive dietary changes in conjunction with weight loss immediately after acute myocardial infarction may modulate blood lipoproteins and significantly reduce complications and mortality after one year.

An Indian experiment with nutritional modulation in acute myocardial infarction

In a randomized, single-blind intervention trial, 406 patients 24 to 48 hours after acute myocardial infarction (AMI) were assigned to either diet A (204 patients, group A) or B (202 patients, group B) for 6 weeks. At entry to the study, mean age, male sex, risk factors, complications, possible and definite AMI, and drug therapy were comparable between the 2 groups. Dietary adherence to intervention and control diets was checked by questionnaire, and drug therapy by tablet count. Group A received significantly lower calories, a higher percentage of calories from complex carbohydrates, vegetable/fish proteins, polyunsaturated fatty acids, and a higher polyunsaturated/saturated fat ratio diet than did group B (higher total calories and saturated fatty acids). Group A also received less dietary cholesterol, salt and caffeine, and higher soluble dietary fiber, vitamins and minerals than did group B. After 6 weeks, group A had a significant decrease in mean serum total (-20.5 vs -8.6 mg/dl) and low-density lipoprotein (-16.6 vs -6.4 mg/dl) cholesterols, and triglycerides (-15.5 vs -7.6 mg/dl), with no decrease in high-density lipoprotein cholesterol (-1.5 vs -1.3 mg/dl) compared with the initial levels and changes in group B. Group A also had a greater decrease in mean body weight (3.4 vs 1.3 kg) than that of group B.(ABSTRACT TRUNCATED AT 250 WORDS)

Effects on serum lipids of adding fruits and vegetables to prudent diet in the Indian Experiment of Infarct Survival (IEIS)

In a randomized, single-blind and controlled trial, the effects of the administration of fruits and vegetables (mean 582 vs. 188 g/day) for 12 weeks were compared as adjuncts to a prudent diet in the management of 202 group A and 204 group B patients with acute myocardial infarction (AMI). Fruits and vegetables decreased total serum cholesterol level (26.4 vs. 13.8 mg/dl, p less than 0.01) low-density lipoprotein cholesterol (20.0 vs. 9.8 mg/dl, p less than 0.01), triglycerides (20.6 vs. 10.6 mg/dl, p less than 0.01) and fasting blood glucose (22.4 vs. 12.6 mg/dl, p less than 0.01) levels more significant in the intervention group than changes in the control group. Adherence to dietary advice was assessed by questionnaires. Total adherence score in group A was significantly higher than in group B. Group A patients also had a significantly smaller rise in lactate dehydrogenase cardiac enzyme which indicates that the protective effects of such a diet may be observed within 1 week. There was a significantly greater decrease in mean blood pressure in group A than changes in group B. These data suggest that fruits and vegetables, because of their high soluble dietary fibre and possibly high antioxidant contents, may be a useful and safe adjunct to a prudent diet in the treatment of patients with AMI. The use of fruits and vegetables may be preferred over oat bran, psyllium and guar gum because of their high content of vitamins and minerals.

Does dietary magnesium modulate blood lipids?

In a randomized, single-blind, controlled study (400 patients aged 25-63 yr; 374 males, 26 females), 206 subjects were administered a magnesium-rich diet, and 194 subjects their usual diet, for 6 wk. Age, sex, body weight, hypertension, hyperlipidemia, smoking, obesity, diuretic therapy, and diabetes were comparable between the two groups, as were laboratory data at entry to the study. Intervention-group A received a significantly higher amount of dietary magnesium and potassium compared to group B, which received its usual diet. After 6 wk, there was a significant fall in total serum cholesterol (228.5 +/- 46.2 mg/dL), LDL cholesterol 146.5 +/- 75.5 mg/dL), and triglyceride (143.8 +/- 40.5 mg/dL) in group A compared to serum cholesterol (242.5 +/- 58.2 mg/dL), LDL cholesterol (157.0 +/- 78.4 mg/dL), and triglyceride (156.5 +/- 60.0 mg/dL) at entry to study, but no such changes in group-B subjects. HDL cholesterol showed a marginal mean decrease of 0.8 mg/dL in group B and a 2.5 mg/dL increase in group A. The changes in blood lipids were consistent with an increased intake of magnesium and with a rise in serum levels. Although a general blood-lipid-reducing effect of such a diet cannot be excluded, it is possible that dietary magnesium may have contributed to the reduction of total serum cholesterol, LDL cholesterol, and triglyceride, and the marginal rise in HDL cholesterol. More studies with longer follow-up periods are needed to confirm this observation.

Dietary strategies for risk-factor modification to prevent cardiovascular diseases

To study the role of diet in cardiovascular risk-factor intervention, 458 high-risk individuals were asked to eat for either a cardiovasoprotective diet (group A, n = 228) or their usual diet (group B, n = 230) in a randomized single-blind fashion. Ages varied between 25 and 63 yr, and 414 were men. Group A received significantly more calories in relation to the amount of complex carbohydrates, vegetable proteins, polyunsaturated fats, fiber, potassium, magnesium, and vitamin C and fewer calories in saturated fat and cholesterol compared with group B. Age, risk factors, nutritional factors, complications, and laboratory data were similar at entry to the study. Dietary adherence was obtained by questionnaire. After 1 yr, there was a significant (P less than 0.02) decrease in total risk factors (32.0%) in group A compared with group B, and 1-yr mean serum cholesterol was significantly lower than the initial mean cholesterol in group A. There was a significant (P less than 0.02) decrease in total complications (38.3%) in group A compared with group B in association with a significant (P less than 0.02) decrease in cardiovascular end points (38.3%), including postexercise electrocardiographic changes, fatal and nonfatal myocardial infarction, and sudden death. Overall mortality and mortality due to ischemic heart disease was less in group A (8 and 3.5%) than group B (11 and 4.8%). However, because of the few cases, differences were insignificant. It is possible that diet causes a significant reduction in blood cholesterol and modification of other risk factors leading to a decrease in complications and cardiovascular end points in patients with risk factors of coronary heart disease.

The effect of diet and aspirin on patient outcome after myocardial infarction

Recent studies show that diet and aspirin therapy inhibit platelet aggregation and may independently reduce complications and mortality in patients after acute myocardial infarction (AMI). To compare the effects of diet and aspirin, 140 patients, who were 4-6 wk post acute myocardial infarction, were assigned either to Group A (placebo with cardiovasoprotective diet) or Group B (aspirin [180 mg daily]) with fat-modified control diet in a single-blind controlled fashion. Of the 140 patients, 7 left the trial before it was completed. Of the remaining 133 patients, 68 in Group A and 65 in Group B were followed for one year. When the study began, the following factors were comparable for both groups: mean age, sex, risk factors, complications of myocardial infarction, electrocardiographic changes, and laboratory data. Group A received a significantly higher caloric intake (P less than 0.02) from complex carbohydrates, vegetable proteins, polyunsaturated fats, and larger amounts of dietary fibers, potassium, magnesium, and vitamin C compared with Group B, which received significantly larger amounts of saturated fats and cholesterol (P less than 0.01). The rehabilitation program, which included reduced smoking, increased exercise and drug therapy, was comparable in both groups. After one year, mean serum cholesterol (223.2 +/- 32.0 mg/dl) and triglyceride (156.2 +/- 13.5 mg/dl) levels in Group A, but not in Group B, were significantly (P less than 0.02) lower compared with mean serum cholesterol (241.2 +/- 39.5 mg/dl) and triglyceride (175.5 +/- 18.5 mg/dl) levels at the beginning of the study.(ABSTRACT TRUNCATED AT 250 WORDS)

Hypermagnesemia following aluminum phosphide poisoning

Aluminum phosphide (ALP) is highly toxic to the lungs, heart and blood vessels causing pulmonary edema, shock and arrhythmias. There is massive focal myocardial damage resulting in raised cardiac enzymes. This study included 92 patients of proven ALP poisoning. The age varied between 20-50 years and the majority (74) were females. Clinical manifestations were nausea and vomiting (92), dyspnea and palpitation (72 each), cyanosis (54), hypotension (32) and shock (46) etc. Cardiac arrhythmias were present in 80 cases and hypermagnesemia in 78 patients. Mean serum magnesium level (1.95 +/- 0.18 mE/l) was significantly (p less than 0.01) raised compared to mean magnesium level in control subjects (1.62 +/- 0.26 mEq/l). Hypermagnesemia results from myocardial and liver damage and to our knowledge has not been described in the literature. Of 92 cases studied, 66 died, 60 of whom died within 24 hours of ALP ingestion. Treatment is supportive.