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Biomedical subjects

D E Grobbee

Publications and source records attributed to D E Grobbee.

At least 451 records · Page 25Linked to original sources
PubMed1990

Coffee, caffeine and hemostasis: a review.

The effects of coffee and caffeine on haemostatic variables are reviewed. The potential relationship between coffee and cardiovascular disease warrants the study of possible links between coffee and haemostasis. The presently available evidence in favour or against such an association, however, is not very convincing and sometimes even conflicting. The findings on fibrinogen level and platelet in vivo activation as measured by plasma beta-thromboglobulin, seem to be the most reliable. If anything, these reports indicate an unfavourable effect of coffee, i.e. coffee may enhance thrombotic tendencies. Before more definite conclusions on the interference of coffee use with the haemostatic system can be made, more data are needed. In particular, randomized studies of coffee and caffeine intake in humans are indicated to assess the impact and the potential significance of coffee in such quantities as are commonly used by millions of people.

Caffeine↗
PubMed1990

A randomized study on coffee and blood pressure.

The effects of coffee on blood pressure and heart-rate and the mediating effect of two common brewing methods, were studied in a randomized trial in 107 young, normotensive adults. After a three-week run-in period, subjects were randomly assigned to one of three groups, receiving either (1) 4-6 cups filtered coffee per day, (2) 4-6 cups boiled coffee per day, or (3) no coffee at all for a period of nine weeks. Because all participants consumed filtered coffee before the trial, the group continuing on filtered coffee was considered as the reference group. Both systolic (SBP) and diastolic blood pressure (DBP) decreased in the abstinence group. Compared to the filter group, only the fall in SBP after 9 weeks was statistically significant, -6.1 mmHg (95% confidence limits -10.8, -1.4). After adjustment for SBP at baseline and body weight change during the study, the observed reduction decreased, to -3.4 mmHg (-7.1, 0.3). The patterns for SBP and DBP were remarkably similar in the groups using either filtered coffee or boiled coffee. After 9 weeks of boiled coffee, mean changes from baseline for SBP and DBP were 0.4 mmHg (-3.7, 4.5) and -0.1 mmHg (-3.4, 3.2), compared to the filter group. The heart rate showed a slight, non-significant decrease in the abstinence group. In conclusion, these findings suggest that abstinence from coffee for a period of several weeks may slightly reduce blood pressure in young normotensive subjects.

Adolescent↗
PubMed1989

The effect on serum cholesterol levels of coffee brewed by filtering or boiling.

Previous reports have indicated that coffee consumption may increase serum cholesterol levels. We studied the effects of coffee prepared by two common brewing methods (filtering and boiling) on serum lipid levels in a 12-week randomized trial involving 107 young adult subjects with normal serum cholesterol levels. After a three-week run-in period during which they all consumed filtered coffee, the participants were randomly assigned to one of three groups receiving four to six cups of boiled coffee a day, four to six cups of filtered coffee a day, or no coffee, for a period of nine weeks. As compared with the change from base line in the filtered-coffee group, the serum total cholesterol level increased after the consumption of boiled coffee by 0.48 mmol per liter (95 percent confidence limits, 0.13 and 0.83), and the low-density lipoprotein cholesterol level increased by 0.39 mmol per liter (95 percent confidence limits, -0.04 and 0.82). There was no significant difference in the change in serum total or low-density lipoprotein cholesterol levels between the filtered-coffee group and the group that drank no coffee. The levels of high-density lipoprotein cholesterol and apolipoproteins were not affected by boiled or filtered coffee. We conclude that drinking filtered coffee does not affect serum lipid levels. The consumption of boiled coffee, however, has an effect on serum cholesterol levels amounting to a mean net increase of 10 percent of the base-line level after nine weeks.

Adult↗
PubMed1989

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.

Adolescent↗
PubMed1989

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.

Age Factors↗
PubMed1989

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.

Adolescent↗
PubMed1989

Abstinence from coffee leads to a fall in blood pressure.

The long-term effects of coffee use on blood pressure and the effects of two common brewing methods were studied for 12 weeks in 107 young normotensives. The subjects were randomly assigned to one of three groups, receiving either (1) 4-6 cups of filtered coffee per day, (2) 4-6 cups of boiled coffee per day, or (3) no coffee for a period of 9 weeks. During the 9 weeks of abstinence, systolic and diastolic blood pressure decreased. The fall in systolic blood pressure amounted to 4.9 mmHg, compared with the filter group (P = 0.02). There was no difference with either brewing method. Our findings suggest that abstinence from coffee may reduce blood pressure in young normotensive subjects.

Adolescent↗
PubMed1989

Interference with dietary habits in young hypertension-prone subjects.

There is growing evidence that the roots of primary hypertension are found in childhood. Since the pathophysiological phenomena that accompany high blood pressure may change during its development, research into the aetiology of hypertension should include relatively young subjects. Altering the blood pressure in children and young adults may also help to prevent hypertension. Unfortunately, it is still difficult to predict which young subjects will become hypertensive later in life. Dietary habits appear to be an important determinant of blood pressure level. Studies on dietary changes in young subjects with elevated blood pressure could therefore provide an insight into the pathophysiological mechanisms linking environment and blood pressure. They may also indicate what preventive measures may be taken in that age group. However, before practical measures can be taken, more studies are needed to clarify both the beneficial and adverse effects that interference with dietary habits may have on young hypertension-prone subjects.

Adolescent↗
PubMed1989

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.

Adolescent↗
PubMed1988

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.

Adolescent↗
PubMed1988

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.

Blood Pressure↗
PubMed1988

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.

Age Factors↗
PubMed1987

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.

Adolescent↗