Selenium status and cardiovascular risk factors in healthy Dutch subjects

To provide further insight into the possible role of selenium in cardiovascular disease, we examined the relationship between cardiovascular risk factors, some nutritional parameters, and short- and long-term selenium status. A total of 82 healthy Dutch volunteers, 59 men and 23 women, aged 40-75 years, were studied. Means and standard deviations of selenium parameters were: plasma selenium 106.4 +/- 23.7 micrograms/L, erythrocyte selenium 0.59 +/- 0.19 microgram/g Hb, toenail selenium 0.78 +/- 0.17 ppm, and erythrocyte glutathione peroxidase activity 28.0 +/- 8.1 U/g Hb. No association was found between selenium status and gender, age, serum total-, LDL-, and HDL-cholesterol, systolic and diastolic blood pressure, alcohol intake, and body mass index. A significantly lower plasma selenium level was observed among smokers compared to nonsmokers (101.0 micrograms/L, SE = 3.9 vs 112.0 micrograms/L, SE = 3.6, p = 0.04). A significant negative association was found between erythrocyte selenium and serum levels of vitamin A and ferritin. No relevant relationship was observed between selenium status and serum fatty acid composition, vitamin E, vitamin B6, and iron. Apart from an association between smoking and short-term selenium status, we found no indications that a possible effect of selenium on cardiovascular disease may operate through the known risk factors.

Serum levels of interleukin-6 are not elevated in patients with Alzheimer's disease

Serum levels of interleukin-6 (IL-6) were determined in 97 patients with clinically diagnosed Alzheimer's disease and 79 age- and sex-matched control subject. Median serum levels of IL-6 did not differ significantly between Alzheimer patients (8.6 U/ml) and controls (8.2 U/ml). Median levels of serum IL-6 were similar for sporadic and familial patients. The concentration of IL-6 was not associated with the severity of the dementia or the duration of the disease since first symptoms. According to these observations there is no evidence for a significant elevation in serum IL-6 in Alzheimer's disease.

Metacarpal bone loss in middle-aged women: "horse racing" in a 9-year population based follow-up study

Differences in the rate of metacarpal bone loss were evaluated in a 9 year population based follow-up study among 799 women initially aged 45-64 years, using initial and follow-up radiographs of the hands. Metacarpal bone loss started around the age of 50 years and was present in more than 95% of the women. The average annual rate of loss was approximately 1% of the initial value. The prevalence of osteopenia increased from 5% for women aged 45-49 years, up to 68% for women aged 70-76. The rate of bone loss was not similar for each individual. Regression analyses of rate of change-in-RCA on initial level of RCA indicated the presence of a consistent subgroup of fast bone losers. However, osteopenia at follow-up was more accurately predicted from initial bone density than from differences in the rate of loss.

Iron status in the acute phase and six weeks after myocardial infarction

In a case-control study of 84 myocardial infarction patients and 84 population controls we investigated the association between iron status parameters and myocardial infarction during the acute phase and after six weeks. Immediately after the infarction mean ferritin levels were significantly higher, whereas iron levels and iron saturation of transferrin were significantly lower in cases than in controls. Six weeks after the infarction, serum iron levels were still significantly lower in cases than in controls. Neither serum ferritin levels nor serum iron levels did show a clear association with the size of the ischemic tissue damage as estimated by creatine phosphokinase levels. Our results indicate that serum ferritin and iron levels are influenced by the traumatic effects of the myocardial infarction. Possibly, these transient changes are an acute effect, as seen in infections. An increased uptake of iron in the reticulo-endothelial system for synthesis of ferritin, may account for the lowered serum iron level and the iron saturation of transferrin.

Twenty-four-hour ambulatory blood pressure pattern in youngsters with a different family history of hypertension: the Dutch Hypertension and Offspring Study

The offspring of hypertensive parents in general show higher casual blood pressure levels during adolescence than the offspring of normotensive parents. Comparative ambulatory blood pressure measurements might reveal the stability and pattern of this difference during circadian blood pressure variation. We studied the 24-h ambulatory blood pressure (Space-Labs 90202 monitor, Redmond, Washington, USA) in youngsters with two hypertensive parents (high; n = 62), with one hypertensive parent (mixed; n = 51) and with no hypertensive parent (low; n = 42). The pattern for both systolic and diastolic blood pressure in the three groups ran parallel, with the high group continuously at a higher level. A clear difference in systolic blood pressure was observed during the day period (high minus low: 5.4 mmHg; 95% confidence range 2.5-8.3). Our data show that offspring of hypertensive parents differ in ambulatory blood pressure levels, but not in the circadian pattern, from the offspring of normotensive parents.

History of dementia and Parkinson's disease in 1st-degree relatives of patients with Alzheimer's disease

We assessed the family history of dementia and Parkinson's disease in 198 Dutch patients with Alzheimer's disease diagnosed before the age of 70 years, and in 198 age- and sex-matched healthy population controls. Of the Alzheimer patients, 48% had at least 1 1st-degree relative with dementia, compared with 19% of the controls. There were 24 patients and 1 control with 2 or more 1st-degree relatives with dementia, yielding a relative risk of 40.0. More Alzheimer patients than controls had a 1st-degree relative with Parkinson's disease, with a relative risk of 2.9. This study strongly confirms earlier findings of familial aggregation of Alzheimer's disease and provides evidence for familial aggregation of Alzheimer's disease with Parkinson's disease. The latter may point at a joint etiology of these diseases.

The association between physical fitness and cardiovascular disease risk factors in children in a five-year follow-up study

The relation between physical fitness and cardiovascular disease (CVD) risk factors was studied in 633 children selected from all fourth grades in 37 elementary schools in New York. They were participating in the control group of an intervention study to reduce CVD risk factors in children. Blood pressure, total and high-density lipoprotein (HDL) cholesterol and physical fitness were measured at baseline and at four subsequent examinations during five years of follow-up. Systolic blood pressure (SBP) at baseline was highest in children with poor physical fitness. The five-year change in physical fitness was inversely associated with the change in SBP, ie, children with the strongest decline in physical fitness showed the largest rise in SBP. HDL cholesterol at baseline was lowest in boys with poor physical fitness. The five-year change in physical fitness was positively related to the change in HDL cholesterol levels in boys; ie, boys with the largest decline in physical fitness had the largest decrease in HDL cholesterol level. These observations indicate that unfavourable long-term changes in physical condition in childhood may be related to unfavourable changes in blood pressure and serum lipids.

Ten-year follow-up study of islet-cell antibodies and childhood diabetes mellitus

To find out whether subclinical autoimmunity precedes onset of nonfamilial insulin-dependent diabetes mellitus (IDDM), 4806 schoolchildren aged 5-19 years from a township in Holland were followed-up for at least ten years after blood was sampled for measurement of islet-cell antibodies (ICA). ICA positivity conferred a relative risk of IDDM of 533 (95% CI 145-1955). In the 10 years of follow-up 4 of the 8 ICA-positive subjects became insulin dependent, whereas the probability of being free of IDDM was 99.9% for those who were ICA-negative at the start of the study. The findings suggest that, although chronic autoimmunity involving the pancreatic beta-cells may precede non-familial IDDM by many years, a positive ICA test on a single occasion predicts the development of IDDM in only 4 out of 8 subjects over a period of 10 years.

Increased risk of atherosclerosis in women after the menopause

An increase in the incidence of cardiovascular disease has generally been observed in postmenopausal women, but there have been few studies of the association between menopausal state and atherosclerosis. In this study 294 premenopausal and 319 postmenopausal women aged 45 to 55 were examined radiographically for calcified deposits in the abdominal aorta, which have been shown to represent intimal atherosclerosis. Aortic atherosclerosis was present in eight (3%) of the premenopausal women and in 38 (12%) of the postmenopausal women. After adjustments for age and other indicators of cardiovascular risk women with a natural menopause had a 3.4 times greater risk of atherosclerosis than premenopausal women (95% confidence interval 1.2 to 9.7; p less than 0.05); women who had had a bilateral oophorectomy had a 5.5 times greater risk (1.9 to 15.8; p less than 0.005). No excess risk of atherosclerosis was observed among women who had had a hysterectomy without removal of both ovaries. These results suggest that when oestrogen production stops, either naturally or after surgery, the risk of atherosclerosis is increased.

Low vitamin B6 status in patients with acute myocardial infarction

The vitamin B6 status of 84 patients with acute myocardial infarction was compared with that of 84 control subjects. Pyridoxal and pyridoxal 5'-phosphate (PLP) in plasma and erythrocytes, as well as the basal and total potential activity of the PLP-dependent enzyme aspartate aminotransferase in erythrocytes, were measured for a comprehensive assessment of vitamin B6 status. The mean levels of all vitamin B6 indexes (except pyridoxal) were lower in the patients than in the control subjects. The differences were statistically significant, except for erythrocyte PLP and total potential enzyme activity. The adjusted relative odds of a myocardial infarction for subjects in the lowest quartile of plasma PLP was about 5 times higher when compared with those in the highest quartile (relative odds = 5.2, 95% confidence interval = 1.4 to 18.9). Similar findings were found with the other vitamin B6 indexes. No significant association between infarct size, as estimated by creatine kinase level, and the vitamin B6 indexes was observed.

Decreased selenium levels in acute myocardial infarction

To study the association between selenium status and the risk of myocardial infarction, we compared plasma, erythrocyte, and toenail selenium levels and the activity of erythrocyte glutathione peroxidase among 84 patients with acute myocardial infarction and 84 population controls. Mean concentrations of all selenium measurements were lower in cases than controls. The differences were statistically significant, except for the plasma selenium level. A positive trend in the risk of acute myocardial infarction from high to low toenail selenium levels was observed, which persisted after adjustment for other risk factors for myocardial infarction. In contrast, erythrocyte glutathione peroxidase activity was significantly higher in cases than controls (31.3 +/- 8.4 U/g of hemoglobin and 28.0 +/- 8.1 U/g of hemoglobin, respectively). Because the toenail selenium level reflects blood levels up to one year before sampling, these findings suggest that a low selenium status was present before the infarction and, thus, may be of etiologic relevance. The higher glutathione peroxidase activity in the cases may be interpreted as a defense against increased oxidant stress either preceding or following the acute event.

Similar plasma atrial natriuretic factor levels in children and young adults with a high and low probability of developing hypertension: the Dutch Hypertension and Offspring Study

The role of atrial natriuretic factor (ANF) in the genesis of primary hypertension is not clear. However, a natriuretic and blood pressure lowering effect has been observed after infusion of ANF. Therefore, subjects at risk of future hypertension might be deficient in ANF or less responsive to it. To address this question we studied ANF, sodium excretion and blood pressure in 180 young normotensive people with different probabilities of developing hypertension later in life. The 180 subjects had either two, one or no hypertensive parents. Sixty-nine offspring had a high, 58 an intermediate and 53 a small probability of developing hypertension ('high', 'mixed' and 'low' groups). Mean plasma levels of ANF did not differ among the three groups of offspring. A negative association was found between ANF and diastolic blood pressure, being most pronounced in the low-risk group. The similar levels of plasma ANF in these groups suggest that ANF is not directly related to the development of high blood pressure.

Incidence and risk factors of Parkinson's disease in The Netherlands

The incidence and some risk factors of Parkinson's disease were investigated in a study performed in The Netherlands. The study was based on a disease register of the Sentinel Stations, which provide a complete ascertainment of new patients with Parkinson's disease in 60 general practices in The Netherlands. The incidence rate of Parkinson's disease in The Netherlands is estimated to be 11/100,000 person-years for men and 12/100,000 person-years for women. Risk factors for Parkinson's disease were investigated in a case-control study in which 86 cases, with the diagnosis of Parkinson's disease confirmed by a neurologist, were compared with 172 reference subjects, matched for age and gender. Cigarette smoking was associated with a lower risk of Parkinson's disease (relative risk 0.6, 95% confidence interval 0.3-1.0). No association was observed between Parkinson's disease and severe head trauma with loss of consciousness, or surgery with total anaesthesia.

Change in blood pressure in offspring of parents with high or low blood pressure: the Dutch Hypertension and Offspring Study

A family history of hypertension is an important predictor of high blood pressure. We investigated the question of whether this predisposition affects the level and change of blood pressure early in life, and in particular, at what age the familial aggregation of blood pressure occurs. Blood pressure and related characteristics were studied in children whose parents both had relatively high blood pressure ('high') and the results were compared with those from children whose parents both had a relatively low blood pressure ('low') and with children with one parent high and the other parent low ('mixed'). At the age of 8 years there were no clear differences in pressure but at the age of 20 years there was a difference of 7 mmHg for both systolic and diastolic pressure between the high- and low-risk offspring. These findings suggest that the magnitude of familial aggregation of blood pressure increases during childhood and adolescence.

Experiences with the lateral calcaneal artery flap

A chronic ulcer of the posterior heel or lateral ankle can be a large problem for the patient. The lateral calcaneal artery flap is a reliable neurovascular local skin flap that can cover the defect after excision of the ulcer in this area. The flap includes the lateral calcaneal artery, sural nerve, and lesser saphenous vein. We performed seven lateral calcaneal artery flaps from 1974 to 1986 for chronic ulcers of the heel or lateral malleolus. None failed. All patients can wear closed shoes. Two donor sites showed secondary healing. One donor site showed hyperkeratosis resulting from inappropriate planning of the flap.

Importance of body weight in determining rise and level of blood pressure in postmenopausal women

Blood pressure in women rises after menopause. In the same period of their lives many women gain weight. Both menopause and increases in body weight may influence blood pressure elevation. To study the association between changes in body weight, age at menopause and duration of menopause, and blood pressure, a prospective follow-up study was conducted in 1167 Dutch women initially aged 45-64 years. After an average follow-up period of 8.9 years 855 women, of 1009 alive at that time, were re-examined (85%). This study indicated that age at menopause and number of postmenopausal years are not directly related to blood pressure rise in middle-aged and elderly women. However, an increase in the body mass index is an important and potentially preventable determinant of increased blood pressure and incidence of hypertension in women of this age group.

Serum copper and zinc and the risk of death from cancer and cardiovascular disease

To investigate the association of serum copper and zinc with mortality from cancer and cardiovascular disease, the authors performed a case-control analysis of data obtained in a Dutch prospective follow-up study. Cancer (n = 64) and cardiovascular disease (n = 62) deaths and their matched controls were taken from a cohort of 10,532 persons examined in 1975-1978. Trace elements were measured in baseline serum samples, which had been stored during the six to nine years of follow-up. The adjusted risk of death from cancer and cardiovascular disease was about four times higher for subjects in the highest serum copper quintile (greater than 1.43 mg/liter) compared with those with normal levels. The excess mortality observed in subjects with low copper status suggests a U-shaped relation. No significant change in the risk of death from cancer and cardiovascular disease was found for subjects with low or high baseline levels of serum zinc. However, a protective effect of a high zinc status on the risk of cancer and cardiovascular disease is compatible with the data. For definitive conclusions, analysis of larger prospective data sets is recommended.

Modification of risk factors for coronary heart disease. Five-year results of a school-based intervention trial

We conducted a study of the effectiveness of an educational intervention designed to modify risk factors associated with coronary heart disease among 3388 children in 37 schools in two demographically dissimilar areas (the Bronx and Westchester County) in and around New York City. Schools within each area were randomly assigned to either intervention or nonintervention groups. In schools targeted for intervention, children in the fourth through eighth grades were taught a teacher-delivered curriculum focusing on diet, physical activity, and cigarette smoking. Risk-factor levels were measured in all schools at base line and at four follow-up points. A total of 1769 of the children qualified for analysis of the intervention effect. After five years, the net mean change in plasma levels of total cholesterol was -1.7 mg per deciliter per year (-0.04 mmol per liter) (95 percent confidence interval, -2.7 to -0.7 mg per deciliter [-0.07 to -0.02 mmol per liter]) in the Westchester County schools, or -8.5 mg per deciliter (-0.22 mmol per liter) (5.1 percent) over a period of five years. In the schools in the Bronx, the net mean change was -1.0 mg per deciliter per year (-0.03 mmol per liter) (95 percent confidence interval, -2.3 to +0.3 mg per deciliter [-0.06 to +0.01 mmol per -2.3 to +0.3 mg per deciliter [-0.06 to +0.01 mmol per liter]), or -5.0 mg per deciliter (-0.13 mmol per liter) (2.9 percent) over a period of five years. Favorable trends in dietary intake and health knowledge were also observed, whereas the other targeted risk factors were not significantly altered. If these findings can be replicated, this will suggest that educational programs to modify coronary risk factors are feasible and may have a favorable (albeit small) effect on blood levels of cholesterol in children.

Raised plasma intact parathyroid hormone concentrations in young people with mildly raised blood pressure

To study the role of parathyroid gland activity in early primary hypertension plasma concentrations of intact parathyroid hormone were measured in 90 untreated young subjects, aged 16-29, with stable midly raised blood pressure and in 40 normotensive control subjects selected from the same population in Zoetermeer, The Netherlands. Intact parathyroid hormone concentration was significantly higher in the hypertensive than the normotensive group (2.34 (SE 0.11) pmol/l v 1.47 (0.13) pmol/l, respectively; difference 0.87 pmol/l; 95% confidence interval 0.55 to 1.21; p less than 0.0001). Serum total calcium concentration was 2.36 (0.01) mmol/l in the hypertensive group and 2.42 (0.01) mmol/l in the normotensive group (difference 0.06 mmol/l; 95% confidence interval 0.02 to 0.09; p = 0.02). Urinary calcium excretion over 24 hours did not differ significantly between the two groups (4.17 (0.28) mmol/24 h in the hypertensive group and 3.89 (0.39) mmol/24 h in the normotensive group; difference 0.28 mmol/24 h; 95% confidence interval -0.66 to 1.22). In the hypertensive group both systolic and diastolic blood pressures increased slightly though significantly with intact parathyroid hormone concentrations. No obvious associations between serum calcium concentration and blood pressure were observed. These findings support the view that enhanced activity of the parathyroid gland may play a part in the early stage of primary hypertension.

Serum lipids in young women before, during, and after pregnancy

The associations between pregnancy and serum lipids were investigated in a cohort of 831 Dutch women, initially aged 5-19 years. These women were examined yearly from 1975 to 1985 for an average period of six years, as part of a longitudinal survey of risk factors for coronary heart disease. During this period, 62 women became pregnant, and their serum total and high density lipoprotein (HDL) cholesterol levels were compared with those of an age-matched reference series of nonpregnant women, derived from the same cohort. Pregnant women showed higher total cholesterol levels (235 +/- 7.4 mg/100 ml) than nonpregnant women (205 +/- 2.7 mg/100 ml). Pregnant women also had higher levels of HDL cholesterol (66 +/- 2.1 mg/100 ml) than their referents (57 +/- 1.0 mg/100 ml). Total and HDL cholesterol increased with duration of pregnancy. When serum lipid levels of pregnant women were compared with the levels one year before and one year after pregnancy, it was observed that the year after pregnancy, HDL cholesterol levels dropped below pre-pregnancy concentrations. At the final examination, women who had ever been pregnant showed lower HDL cholesterol levels than those who had never been pregnant. The difference was most marked in users of oral contraceptives. These observations suggest that serum total and HDL cholesterol levels are elevated during pregnancy, probably because of hormonal changes. Furthermore, they point to a possibly lowering effect of parity on HDL cholesterol. These findings may help to explain the reported positive association between parity and the occurrence of cardiovascular diseases.

Acute antiischaemic properties of high dosages of intravenous diltiazem in humans in relation to its coronary and systemic haemodynamic effects

The antiischaemic properties of intravenous diltiazem in recommended therapeutic doses are disputed. In 17 patients with coronary artery disease the systemic and coronary haemodynamic effects of diltiazem were assessed during a high-dose infusion (0.4 mg kg-1 per 5 min, followed by 0.4 mg kg-1 per 10 min). In addition, its potential antiischaemic properties were investigated during identical pacing stress tests, 30 minutes before (P1) and immediately after diltiazem administration (P2). Diltiazem reduced left ventricular systolic pressure from 133 +/- 5 to 116 +/- 5 mmHg (P less than 0.005, means +/- SEM), persisting until after P2. It decreased systemic and coronary resistance by 32% (P less than 0.001) and 29% (P less than 0.005), respectively, with a sustained increase in cardiac output from 5.9 +/- 0.4 to 7.3 +/- 0.6 l min-1 (P less than 0.01), but a brief 20% rise in coronary flow (P less than 0.05), after the bolus infusion only. Heart rate, contractility, left ventricular filling pressure and myocardial O2 consumption remained unchanged. Despite high plasma levels (673 +/- 81 micrograms l-1) diltiazem was well tolerated. During identical maximal pacing rates diltiazem considerably reduced myocardial O2 demand (double product: 16.3 +/- 0.8 (P2) vs 21.1 +/- 1.1 (P1), P less than 0.005), due to an 18% decrease in left ventricular systolic pressure, resulting in diminished coronary flow and myocardial O2 consumption during P2 (14% and 15%, respectively, P less than 0.05 vs P1). Diltiazem also significantly reduced pacing-induced ischaemia, indicated by normalization of myocardial lactate extraction (1 +/- 8% (P2) vs -41 +/- 12% (P1), P less than 0.05), and left ventricular filling pressure (13 +/- 2 (P2) vs 27 +/- 3 mmHg (P1), P less than 0.01), less ST-segment depression (0.12 +/- 0.01 (P2) vs 0.24 +/- 0.02 mV (P1), P less than 0.01) and improved contractility (Vmax 59 +/- 5 (P2) vs 48 +/- 3 s-1 (P1), P less than 0.05). Angina was absent or less in 15 patients during pacing after diltiazem. Thus, diltiazem, in high dosages, induces continuing systemic but short lasting coronary vasodilation, improves pump function without negative chronotropic and inotropic effects and has pronounced antiischaemic properties, predominantly due to diminished myocardial O2 demand.

Determinants of rise in blood pressure in normotensive children

Thirty-nine initially normotensive children (25 girls) with a large increase in systolic blood pressure (SBP) over a period of 7 years were compared with 78 children with a small increase, matched for age and gender. They were selected from a random sample of 596 Dutch children who were examined at an initial examination and 4 weeks later, and at yearly intervals thereafter. Body weight, height and Quetelet index at baseline were similar in children with a large rise in SBP and those with a small rise. Children with a large increase had a larger weight gain during follow-up than those with a small rise. Parental blood pressure (BP) and parental history of diabetes mellitus and cardiovascular diseases did not differ between the study groups. Cardiovascular reactivity as assessed by a cold-pressor test at baseline did not differ between the study groups, nor did urinary sodium excretion during follow-up. Total tobacco consumption was larger in those with a small increase. Children with a large rise in SBP experienced a larger fall in SBP from the initial to the 4-week examination. The individual variability of BP over the whole observation period did not differ between the study groups. These observations suggest that a fall in BP after a short follow-up period may be indicative of high BP in the years to come.

Selenium status and chronic disease mortality: Dutch epidemiological findings

This paper summarizes Dutch epidemiological findings on the impact of a low selenium (Se) status on mortality from cardiovascular disease (CVD) and cancer. Se status parameters of Dutch subjects are compared to those from Finland and the USA, and the concept of a threshold effect for Se on disease risk is discussed. Case-control analyses of prospective data suggest that low serum Se (below 105 micrograms/l) is not clearly associated with an excess risk of CVD death (relative risk RR = 1.6, 90% confidence interval Cl = 0.9-2.9). Se cancer findings indicate a possible gender difference in risk (in males RR = 2.7, 90% Cl = 1.2-6.2; in females RR = 1.5, 90% Cl = 0.5-4.5). Larger studies, monitoring a combination of Se status parameters are recommended.

Socioeconomic status, ethnic origin, and risk factors for coronary heart disease in children

The associations between socioeconomic status, ethnic origin, and risk factors for CHD were studied in 2,591 white and black children from two socioeconomically dissimilar populations in the New York City area. The study subjects were selected from all fourth graders in 44 elementary schools. Blood pressure, plasma lipids, body mass index, and physical fitness were measured. In a random subsample of 353 subjects, a 24-hour dietary recall interview was performed. White children in the lower socioeconomic area had the most unfavorable risk factor profile. Differences between the groups in mean level of plasma total cholesterol primarily were associated with factors related to area of residence. Children in a lower socioeconomic environment may be considered to be candidates for especially intensive intervention strategies for the primary prevention of CHD.

Serum selenium, vitamin antioxidants, and cardiovascular mortality: a 9-year follow-up study in the Netherlands

The association between low serum selenium, vitamin A, and vitamin E levels and mortality from cardiovascular disease (CVD) was investigated in a case-control study nested in a 9-yr prospective study in the Netherlands. For 10,532 persons aged greater than or equal to 5 yr who participated in a 1975-1978 medical survey, serum was stored at -20 degrees C. For the 84 of 106 subjects aged 37-87 yr who died of CVD after the baseline exam, 168 cohort members alive at the end of 1983 and matched for age and gender were selected as controls. No significant associations between serum selenium. vitamin A, vitamin E, and CVD mortality were observed before and after multivariate analyses. The adjusted risk of death from CVD for subjects in the lowest selenium quintile (less than 105.0 micrograms/L) was 1.6 (95% CI, 0.8-3.2). For coronary and stroke death risk, estimates were 1.1 (95% CI, 0.5-2.6) and 3.2 (95% CI, 0.8-12.1). Our findings do not show a clear CVD risk from low selenium and vitamin levels. Although some of the risk estimates were strong, larger studies are required for definitive conclusions.

Blood pressure and physical fitness in children

The association between physical fitness and blood pressure was studied in 2061 children selected from all fourth graders in 44 elementary schools in the New York City area. Their blood pressure and physical fitness were measured on two consecutive examinations 1 year apart. Systolic and diastolic blood pressure were highest in children with poor physical fitness. The change in physical fitness between the 2 examination years was related to the change in systolic and diastolic blood pressure (i.e., children with a decline in physical fitness showed the largest rise in blood pressure). These observations suggest that the level of systolic and diastolic blood pressure in children is associated with the level of physical fitness. They also indicate that change in blood pressure in childhood may be related to change in physical fitness.

Sodium restriction and potassium supplementation in young people with mildly elevated blood pressure

Forty young subjects, aged 18 to 28 years, with mildly elevated blood pressure participated in a double-blind randomized three-period crossover study of the effect of sodium restriction with and without potassium supplementation on blood pressure. Dietary sodium intake was restricted for 18 weeks in which the patients received in random sequence 'slow-sodium' (90 mmol/day), 'slow-potassium' (72 mmol/day), and placebo tablets, each for 6 weeks. Mean urinary sodium excretion was 129 mmol/24 h in the slow-sodium period, 57 mmol/24 h during placebo, and 69 mmol/24 h during slow-potassium. Mean supine systolic blood pressure in the sixth week of the slow-potassium period was 3.3 mmHg lower than that at the end of the slow-sodium period (P less than 0.05). There was no significant difference in systolic or diastolic blood pressure between the placebo and the slow-sodium periods. The fall in systolic blood pressure in the low sodium/high potassium period was accompanied by a fall in cardiac index of 0.4 l/min per m2 body surface area (BSA) (P = 0.03). Our observations suggest a small hypotensive effect of moderate sodium restriction combined with high potassium intake in young hypertensive subjects. Sodium restriction alone has little effect on blood pressure in this group. The combination of a low sodium/high potassium diet may lower blood pressure by affecting cardiac output. Reducing the dietary sodium:potassium ratio may therefore be useful in the management of early primary hypertension.

Dose related coronary and systemic haemodynamic effects of intravenous bepridil in patients with coronary artery disease

The acute coronary and systemic haemodynamic effects of intravenous bepridil were investigated in 27 patients with coronary artery disease; 13 (group 1) received 2 mg kg-1 and 14 (group 2) 4 mg kg-1 over 5 min. An immediate systemic and coronary vasodilation occurred in both groups during and immediately after the infusion. Changes were dose-related with a maximal decrease in left ventricular (LV) systolic pressure of 11% (group 1) and 18% (group 2), in mean aortic pressure of 11% (group 1) and 19% (group 2), and in coronary resistance of 23% (group 1) and 41% (group 2). Coronary flow increased by 17% (group 1) and 47% (group 2) (all changes significantly different from control (C) values and between groups). Cardiac output, measured immediately after bepridil, was unaltered, although in group 2 stroke volume index increased (14%) and systemic resistance decreased (16%), both P less than 0.05 vs C. In group 2, heart rate (HR) and contractility initially increased (8% and 10%, respectively, P less than 0.05 vs C), secondary to the greater fall in afterload, followed by a significant reduction at 5 and 10 min after bepridil (9% and 10%, respectively), accompanied by a 36% increase in LV enddiastolic pressure (P less than 0.05 vs C). No such changes were observed in group 1, apart from a simultaneous decrease in HR (9%, P less than 0.05 vs C). Thus, in humans, a dose-related, biphasic haemodynamic pattern is observed with intravenous bepridil, consisting of an acute, short-lasting vasodilation, followed by late negative chronotropic and inotropic effects, which, with longterm bepridil administration, may be beneficial during myocardial ischaemic.

Is serum selenium a risk factor for cancer in men only?

The association of serum selenium with the subsequent risk of death from cancer was investigated in a case-control study that was nested in a prospective nine-year follow-up study in the Netherlands. In 1975-1978, 10,532 persons in the Dutch town of Zoetermeer who were aged five years or more participated in a medical survey. Serum samples were collected and stored at -20 C. For the 82 persons who died of cancer since the baseline examination, 164 cohort members still alive by the end of 1983 were selected as controls and matched for age, sex, and smoking. Cancer deaths that occurred in the first year of follow-up were excluded, leaving 69 cases for statistical analyses. The mean serum selenium level of 116.7 +/- 4.0 micrograms/liter among male cancer deaths (n = 40) was significantly different (p = 0.04) from that in the control subjects (126.4 +/- 3.1 micrograms/liter). In females, selenium levels were similar among cases and controls. The adjusted risk of death from cancer for men in the lowest quintile of serum selenium (below 100.8 micrograms/liter) was more than twice that of subjects with higher levels (relative risk = 2.7,90% confidence interval = 1.2-6.2). These data support recent findings of an increased cancer risk associated with low serum selenium levels in men but not in women.

Is the ratio of apo B/apo A-I an early predictor of coronary atherosclerosis?

It is unknown which lipoprotein in childhood is the best predictor of atherosclerosis later on in life. We measured serum triglycerides, total cholesterol, its subfractions (LDL, HDL, HDL2, HDL3) and apoproteins (A-I, A-II, B) in two groups of children. They were offspring of fathers who had severe coronary atherosclerosis or no coronary sclerosis, as determined by coronary angiography. Fasting blood lipids were measured in 49 children of fathers with severe sclerosis, and in 37 children of fathers without sclerosis. Sons of fathers with severe coronary atherosclerosis had higher levels of apo B and of the ratio apo B/apo A-I than sons of fathers free of atherosclerosis. No differences in lipid levels in daughters were observed. These observations suggest that apolipoproteins play a part in early atherogenesis. They further indicate that it may be possible to detect children who have a high probability of developing severe coronary atherosclerosis later in life.

The effect of large doses of ethinylestradiol on apolipoprotein levels in excessively tall prepubertal girls

Seventeen constitutionally tall prepubertal girls, aged 10 to 14 years, were treated with large doses of ethinyl estradiol (EE) to reduce their final height. The serum concentration of cholesterol, triglyceride, and apolipoproteins before and after four to 17 months of treatment were compared with the same variables in a reference group, initially matched for bone age and height. In the patients, cholesterol rose by 24% (1.1 +/- 0.8 mmol/L), triglyceride by 105% (0.97 +/- 0.70 mmol/L), LDL apo B by 48% (27 +/- 19 mg/dL), apo A-I by 45% (62 +/- 17 mg/dL), and apo A-II by 21% (12 +/- 11 mg/dL). In the reference group, none of these variables changed significantly. The ratio of LDL apo B/apo A-I remained constant in both groups.

Effect of calcium supplementation on diastolic blood pressure in young people with mild hypertension

In a double-blind trial 90 mildly hypertensive subjects aged 16-29 years were randomly assigned to 1 g calcium per day or placebo. Calcium supplementation did not affect systolic blood pressure, but at six and twelve weeks diastolic blood pressure had fallen by 3.1 (p = 0.04) and 2.4 (p = 0.11) mm Hg, respectively, more in the calcium group than it had in the placebo group. Subjects with a baseline plasma parathyroid hormone (PTH) higher than the median showed a 6.1 mm Hg (p = 0.01) greater fall in diastolic blood pressure after six weeks and 5.4 mm Hg (p = 0.01) after twelve than in the placebo group. The fall in diastolic blood pressure was greater in the calcium group than in the placebo group in subjects with a lower than median serum total calcium and in those with a large bodyweight. Calcium supplementation may lower blood pressure in young people with mildly raised blood pressure, particularly in those with high plasma PTH and/or low serum total calcium.

Does sodium restriction lower blood pressure?

Data from 13 randomised trials on the effect of sodium restriction on blood pressure were analysed. The hypotensive effect of sodium restriction was found to be small and restricted largely to systolic blood pressure, which fell by an average of 3.6 mm Hg (range 0.5-10.0 mm Hg). The reduction increased with age and in those with higher blood pressure. Sodium restriction therefore seems to be of limited use in those who are most eligible for non-pharmacological treatment of high blood pressure--namely, young patients with mild hypertension.

Coronary heart disease prevention in childhood: one-year results of a randomized intervention study

A six-year intervention study of the feasibility and effectiveness of a program aimed at the primary prevention of coronary heart disease (CHD) has been initiated among children in six school districts in Westchester County, New York. Schools randomly were assigned either to the intervention program or to a control group. The intervention program consists of a curriculum focusing on nutrition, physical fitness, and cigarette smoking prevention. The study population at baseline comprised 1,822 fourth-graders. This paper presents the findings at baseline and at one-year follow-up for the following target risk factors: systolic and diastolic blood pressure, plasma total and high-density lipoprotein (HDL) cholesterol, serum thiocyanate, ponderosity index, triceps skinfold thickness, and postexercise pulse recovery rate. After one year of intervention, the program was found to be acceptable to school administrators, teachers, parents, and children. Small net changes in the favorable direction were observed for diastolic blood pressure and thiocyanate. Intervention programs in schools may, after sufficient duration, prove to be effective in lowering CHD risk.

Intact parathyroid hormone (1-84) in primary hypertension

Intact parathyroid hormone (1-84) (PTH) concentrations were measured in serum of 83 hypertensive and 83 normotensive subjects, aged 20 to 69 years, matched for age and gender, and selected from the same open population. No significant differences in serum intact-PTH levels were found between the total group nor between groups based on three age strata. However, PTH was negatively associated with body weight and after adjustment for differences in body weight, significantly higher intact-PTH levels were found in hypertensive than in normotensive subjects, aged 20-39 years, but not in those aged 40 to 69 years. Our findings suggest that body weight is a confounding variable when comparing differences in intact-PTH between groups. Intact-PTH levels may be increased in a subgroup of young primary hypertensive subjects.

Non-pharmacological intervention in primary hypertension in childhood

In children with blood pressure levels persistently in the upper part of the distribution and without evidence for known causes of hypertension, one may ask which approach should be used to lower blood pressure. In general, non-pharmacological intervention will be preferred over drug treatment as a first choice in children with primary hypertension. No specific non-pharmacological treatment is available for children with high blood pressure. The main objective of this review is to underscore the need for further intervention studies in hypertensive children. Although the scientific evidence is rather scanty, some general recommendations concerning body weight, physical activity and fitness, dietary intake of electrolytes and relaxation procedures can be made. In obese children, weight reduction, combined with increase of physical activity, is the measure of first choice to lower blood pressure. In children with a high sympathetic outflow, as evidenced by high levels of circulating catecholamines, increase of physical activity and use of relaxation procedures may be the first approach to lower blood pressure. In children with evidence for disturbances in electrolyte metabolism, as evidenced by high intralymphocytic sodium, low serum calcium, or high PTH, a dietary approach to high blood pressure may be used. In these children, an increase of potassium intake or calcium intake seems a promising way to lower blood pressure.

Primary prevention of chronic disease in childhood: changes in risk factors after one year of intervention

A five-year intervention study of the feasibility and effectiveness of a program aimed at the primary prevention of chronic disease was initiated in 1980 among children in 22 elementary schools in the Bronx, New York. Schools randomly were assigned either to the intervention program or to a control group. The intervention program consists of a curriculum focusing on nutrition, physical fitness, and cigarette smoking prevention. The study population at baseline comprised 2,283 fourth-graders. Subjects were eligible at baseline and at one-year follow-up for participation in a medical examination in which the following target risk factors were measured: systolic and diastolic blood pressures, plasma total and high-density lipoprotein (HDL) cholesterol, serum thiocyanate, ponderosity index, triceps skinfold thickness, and postexercise pulse recovery rate. After one year of intervention, systolic pressure increased less in the intervention group than among controls. Diastolic pressure decreased in both groups, but more in the intervention subjects than in controls. Total cholesterol decreased in the intervention group while increasing among controls. Significant net changes in the favorable direction also were observed for total cholesterol/HDL cholesterol ratio and for thiocyanate. These observations indicate that it is feasible to implement a school-based program aimed at the primary prevention of chronic disease. The intervention program appears to have had a favorable effect on several target risk factors. Although the effects were relatively small, intervention programs in schools may prove to be effective in lowering chronic disease risk.