Biomedical subjects

P Leren

Publications and source records attributed to P Leren.

At least 19 recordsLinked to original sources

PubMed1996

Smoking habits and risk of fatal stroke: 18 years follow up of the Oslo Study.

STUDY OBJECTIVE: To examine the risk of fatal stroke in relation to smoking habits in men screened for the Oslo study. DESIGN: The Oslo study is a prospective, cohort study of the epidemiology and preventive aspects of cardiovascular diseases in middle aged men. Screening started in May 1972 and results after 18 years of follow up are reported. PARTICIPANTS: There were 16209 men aged 40-49 years, of whom 16173 had no stroke history. Eighty five men died from stroke, of whom 48 were daily cigarettes smokers, 7 were pipe and cigar smokers, 15 smoked cigarettes and pipe or cigars daily, 11 were previous cigarette smokers, and 4 had never smoked cigarettes. MAIN RESULTS: Results of proportional hazards regression analysis adjusted for age, diastolic blood pressure, and glucose concentration showed the following rate ratios (RR) (95% confidence interval) of smoking groups compared with those who had never smoked or had previously smoked: combined cigarette and cigar or pipe smokers, RR = 6.1 (3.0, 12.5); cigarettes only, RR = 4.1 (2.3,7.4); and pipe and/or cigars only RR = 2.2 (0.9,5.5). The overall, age adjusted risk of smoking cigarettes daily was 3.5 and was found to increase with increasing cigarette consumption. Regardless of their smoking group, stroke cases had increased diastolic (DBP) and systolic blood pressure (SBP) when compared with men who had not had a stroke. The absolute differences in DBP and SBP between stroke cases and others for never and previous cigarette smokers versus daily smokers were twice as large: DBP, 12.1 mmHg versus 6.5 mmHg respectively and SBP, 16.0 mmHg versus 7.1 mmHg respectively. A high BMI increased the risk of fatal stroke of never and previous cigarette smokers. Men being treated for hypertension at the time of screening had three times the crude risk of fatal stroke of men who were not taking hypertensive treatment. CONCLUSIONS: Daily cigarette smoking increased the risk of fatal stroke three and a half times. Combined cigarette and pipe or cigar smoking had a higher risk than smoking cigarettes only. An increased risk was found in relation to increased daily cigarette consumption.

Adult↗

PubMed1995

Risk of fatal stroke according to blood pressure level: an 18-year follow-up of the Oslo Study.

OBJECTIVE: To determine how blood pressure level predicts the incidence of fatal stroke. DESIGN: The Oslo Study is a prospective cohort study of preventive and epidemiological aspects of cardiovascular disorders in middle-aged men. Of 25,915 men invited, 16,209 aged 40-49 years attended the screening. A 7% random sample of men aged 20-39 years were also invited to attend. METHODS: The screening started in May 1972 and the analysis presented is an 18-year follow-up for fatal strokes. Men with a history of stroke were excluded from the analyses. RESULTS: Of 16,173 men with no history of stroke 85 died from stroke. Results from Cox proportional hazards regression analysis confirm diastolic (DBP) and systolic blood pressure (SBP) as strong independent risk factors of fatal stroke, with DBP being the stronger predictor. Analyses of risk of fatal stroke by quintile values show SBP to give significantly increased risk from the third quintile (136 mmHg), and DBP from the fifth quintile (95 mmHg) relative to the first quintile. No levelling off at highest levels can be seen when analysing decile values. No J-shape of the curve was evident. Men on drug treatment for hypertension with no stroke history (n = 440) had 4.7-fold (crude) and 2.8-fold (adjusted for age and DBP) the rate of stroke mortality of men not on drug treatment for hypertension. CONCLUSION: DBP was a stronger predictor than SBP, with increasing risk from the fifth quintile of DBP and the third quintile of SBP. Men on drug treatment for hypertension at screening were at increased risk during the follow-up period, indicating that their treatment did not sufficiently reduce their risk of stroke.

Adult↗

PubMed1995

Nonfasting serum glucose and the risk of fatal stroke in diabetic and nondiabetic subjects. 18-year follow-up of the Oslo Study.

BACKGROUND AND PURPOSE: The association between nonfasting serum glucose and stroke mortality for diabetic and nondiabetic subjects is presented for participants of the Oslo Study. METHODS: The study started in 1972; of 16,209 men aged 40 to 49 years, 16,172 had no previous history of stroke and 151 were known to be diabetic. Five diabetic and 80 nondiabetic subjects died of stroke during the 18 years of follow-up, giving a rate ratio of 7.87 (95% confidence interval [CI], 2.48 to 19.14). The rate of mortality for all causes in diabetic subjects was more than five times that of those who were nondiabetic. RESULTS: Nonfasting serum glucose was a predictor of fatal stroke in all participants (diabetic subjects included) without a history of stroke in age-adjusted univariate analysis. The relative risk was 1.13 (CI, 1.03 to 1.25) by increase of 1 mmol/L of serum glucose according to results of proportional hazards regression analysis. Accordingly, relative risk for nondiabetic subjects was 1.02 (CI, 0.83 to 1.26) with no linear trend. The rate ratio of the fifth quintile to the rest was 1.57 (CI, 0.94 to 2.56) for all participants and 1.28 (CI, 0.72 to 2.18) for nondiabetics. CONCLUSIONS: There was an interaction between glucose level and body mass index versus stroke for all participants but not for nondiabetic subjects, with an increased risk for men with above-median values of glucose and body mass index. Analysis of nondiabetic subjects failed to show glucose as a definite predictor of fatal stroke.

Adult↗

PubMed1994

Quality-adjusted meta-analysis of the hypertension/coronary dilemma.

Primary investigators of randomized drug trials in hypertension were invited to rate quality of such trials. The intention of the survey was to ask if antihypertensive drug therapy reduces incidence of coronary heart disease (CHD) in hypertensive patients. Response was obtained for 7 of the 11 invited investigators, covering 69% of patients and 75% of CHD cases. Principal component analysis was used to construct a quality score based on answers to 12 questions along visual analog scales. The score correlated well with the answer to a global question of overall quality given by the raters. No systematic tendency toward favoring one's own trial could be demonstrated, therefore, all raters have contributed to the rating. The trials with the highest rated quality to answer the research question were Systolic Hypertension in the Elderly Program (SHEP), Australian National Blood Pressure Study, Medical Research Council, Veterans Administration, and European Working Party of Hypertension in the Elderly. The large Heart Detection and Follow-up Program (HDFP) trial was rated at 11th place among the trials with a score of < 40% of the SHEP. The small trials performed in the 1960s were placed at the bottom of the ranking list. Because SHEP is the only trial without diastolic hypertension, results were given with and without SHEP results. When incorporating the quality score into a meta-analysis of CHD outcome, results were dependent on whether SHEP was included or not. For diastolic hypertension only, the effect of therapy was estimated to be about 8% for all higher quality studies, whereas inclusion of the lower quality HDFP changed it to 14%. When isolated systolic hypertension trial was pooled with the others, no major relation to quality rating was observed. A 14% CHD preventive efficacy was established when pooling the three top quality studies. This stayed unchanged until HDFP at rank 11 was included raising this estimate to 16%. Inclusion of the two latest published trials in the elderly, the Medical Research Council trial of treatment of hypertension in older adults and the Swedish Trial in Old Patients with hypertension, did not change this overall estimate of 16% (standard error = 3.8%). It is concluded that if all randomized drug trials in hypertension had the same treatment efficacy, the estimated CHD prevention would be in the range of 15%. Subgroup analyses revealed no relationship to age, but a difference in efficacy was shown depending on whether the trials were performed in the United States or elsewhere. Also, patients at higher risk levels showed better benefit than lower risk patients.

Adult↗

PubMed1993

Mortality in relation to smoking history: 13 years' follow-up of 68,000 Norwegian men and women 35-49 years.

A total of 44,290 men and 24,535 women aged 35-49 have been followed with respect to different causes of death during 13.3 years on average. A detailed history of smoking, together with other important risk factors, were recorded in a standardized way. Compared with the classical American and British studies, the excess mortality for the smokers was largely the same for the majority of causes. The exceptions were cerebrovascular mortality and suicides and accidents, which were more strongly related to smoking in this study. Furthermore, men who smoked only pipe, had nearly the same coronary heart disease mortality as men who smoked only cigarettes. The same applies to lung cancer mortality. Among men who had quit cigarette smoking, the coronary heart disease mortality decreased with time since quitting to almost the level of the never cigarette smokers after 5 years or more.

Accidents↗

PubMed1993

Sixteen years of plasma exchange in a homozygote for familial hypercholesterolaemia.

This report describes 16 years of plasma exchange in a female familial hypercholesterolaemia homozygote. During childhood she had values for total serum cholesterol of 25-30 mmol l-1. She developed tendon and skin xanthomas before the age of 12 months. Because her total serum cholesterol level was not satisfactorily changed by lipid lowering drugs, plasma exchange was started in 1976. Since then she has had plasma exchange every 3 weeks. She has now reached the age of 42. Her pre-exchange values for serum cholesterol have been 11.1 mmol l-1 (6.79-28.8), while her post-exchange values have been 4.17 mmol l-1 (1.65-10.47). There has been a considerable regression of her xanthomas, and her xanthelasmas have disappeared. No side-effects have been observed during the 16 years of plasma exchange.

Adult↗

PubMed1993

The predictability of risk factors with respect to incidence and mortality of myocardial infarction and total mortality. A 12-year follow-up of the Oslo Study, Norway.

OBJECTIVES: To study the prognostic value of several risk factors on incidence and mortality of myocardial infarction (MI) and total mortality in men. DESIGN: Prospective cohort study of 12 years' follow-up. SETTING: All men in Oslo aged 40-49 and a 7% sample of men aged 20-39 were invited for screening. SUBJECTS: Of all 30,025 invited men, of whom 25,015 were aged 40-49, a total of 16,209 men aged 40-49 attended the screening and risk factors were recorded for these men. MAIN OUTCOME MEASURES: Incidence of first MI (non-fatal and fatal), mortality of MI, total mortality. RESULTS: When examining the rate ratio of the fifth to the first quintile of risk factors we found that systolic and diastolic blood pressures were stronger predictors for mortality than incidence of MI. The rate ratios (95% confidence interval) of systolic blood pressure were 3.73 (2.56, 5.44) and 2.56 (2.01, 3.25) respectively. For diastolic blood pressure the corresponding rate ratios were 4.14 (2.84, 6.04) and 2.78 (2.18, 3.54). Small differences in the rate ratios for these end-points were found for total serum cholesterol and triglycerides. Daily cigarette smoking versus non-cigarette smoking was a stronger predictor for MI mortality than incidence, with rate ratios of 3.16 (2.45, 4.24) and 2.34 (2.00, 2.79) respectively. The Cox proportional hazards regression analysis confirmed the above results. CONCLUSIONS: Total serum cholesterol and triglycerides predicted incidence and mortality of MI equally well. Whereas blood pressure and daily cigarette smoking predicted mortality of MI more strongly.

Adult↗

PubMed1993

Ischaemic heart disease: how well are the risk profiles modulated by current beta blockers?

In acute myocardial infarction, intravenous beta blocker therapy has been tested in about 30 controlled, randomized trials. Of these, the ISIS-1 using atenolol and the MIAMI trial using metoprolol are the most important. In a total of 26,437 patients, total deaths were reduced by 62 during day 1 and by 64 during the first week, i.e. 97% of the lives were saved during the first day of beta blocker treatment. In post-myocardial infarction, oral beta blocker maintenance treatment has been used in about 35,000 survivors in placebo-controlled trials. Of these, the timolol, metoprolol and propranolol (BHAT) trials are the most important. In the timolol trial lasting for 33 months, total death, total cardiac death and re-infarction rate were significantly reduced. In the metoprolol study lasting for 3 months, total and cardiac mortality were reduced, and in the BHAT study lasting for 25 months fatal and non-fatal re-infarction combined was significantly reduced. Primary prevention of coronary heart disease has been the intention in hypertension trials. Despite the fact that beta blockers are potent agents against elevated blood pressure, a well-established coronary risk factor, no controlled trial with a placebo or untreated control group has shown a definite preventive effect on coronary heart disease. The reason for this apparent paradox is not known, but many speculations have been aired that the lack of effect might be due to adverse metabolic effects of most beta blockers.

Adrenergic beta-Antagonists↗

PubMed1993

Risk factors of stroke incidence and mortality. A 12-year follow-up of the Oslo Study.

BACKGROUND AND PURPOSE: The objective of this study was to determine the risk factors of stroke incidence and mortality. METHODS: Our data are based on a prospective cohort study of men aged 40 to 49 years after 12 years of follow-up. RESULTS: In age-adjusted Cox proportional-hazards regression analysis of 14,403 healthy men, diastolic blood pressure was a stronger predictor for stroke incidence and mortality than systolic blood pressure. Smoking was a stronger predictor of mortality than of incidence. However, there was no dose-response relation among smokers by increased cigarette consumption. Total serum cholesterol was a significant (P < .05) risk factor for stroke mortality and of borderline significance (P = .08) for stroke incidence. Increased physical activity at leisure was associated with reduced stroke incidence but not mortality. The myocardial infarction risk score comprising systolic blood pressure, total serum cholesterol, and daily cigarette smoking was a strong predictor of mortality and incidence. Body mass index, triglycerides, blood glucose, and physical activity at work were not found to be risk factors for stroke. CONCLUSIONS: Reduction of blood pressure, cessation of smoking, lowered cholesterol, and increased physical activity at leisure are individual measures to reduce the risk of stroke.

Adult↗

PubMed1992

Long-term effect of lovastatin alone and in combination with cholestyramine on lipoprotein (a) level in familial hypercholesterolemic subjects.

We have determined the effect of lovastatin alone or in combination with cholestyramine on lipoprotein (a) [Lp(a)] levels in 59 heterozygotes for familial hypercholesterolemia (FH) treated for 33.8 (+/- 6.1) months. The median pretrial Lp(a) value was 10.2 mg/100 ml, which is twice the median value in healthy people examined at the Institute of Medical Genetics, University of Oslo. The median Lp(a) level was insignificantly reduced by 10.3% during the first 20 weeks when the subjects were on a standardized medication of increasing doses of lovastatin and cholestyramine. The first 20 weeks were followed by usual care treatment period, and a further decrease in Lp(a) level to 16.2% (P = 0.0012) was observed at the end of the study. Comparison between the 20 subjects on lovastatin monotherapy and the 31 subjects on the combined therapy of lovastatin and cholestyramine, revealed that the subjects on monotherapy had a median reduction of 20.1%, and the subjects on the combined therapy had a reduction of 15.4%. Thus, it appears that the reduction in Lp(a) level could be ascribed to lovastatin alone.

Adolescent↗

PubMed1992

The cardiovascular effects of alpha-receptor blocking agents.

OBJECTIVE: To characterize selective alpha 1-adrenergic blockers as antihypertensive agents, particularly doxazosin. CHARACTERISTICS OF ALPHA-BLOCKERS: These agents lower elevated blood pressure by reducing peripheral arterial resistance without increasing the heart rate or reducing cardiac output. They also reduce left ventricular hypertrophy; improve an atherogenic lipid profile; reduce the risk of thrombotic complications; reduce the formation of fatty streaks, the precursor of advanced athersclerosis; have no adverse metabolic effects in diabetic hypertensives; have a comparable side-effect profile to that of other antihypertensive drugs; and are cost-effective. CONCLUSIONS: In addition to reducing high blood pressure, the alpha-blockers reduce a number of other cardiovascular risk factors. In attempts to solve the hypertension-coronary dilemma, these additional effects may prove to be of crucial importance.

Adrenergic alpha-Antagonists↗

PubMed1990

Childhood traumas and psychosocial characteristics of 50-year-old men with essential hypertension.

The aim of the present study was to describe childhood traumas and other psychosocial characteristics of middle-aged men with never-treated essential hypertension. Hypertensive (N = 17) and normotensive (N = 18) 50-yr-old men were selected from the Oslo Study of Cardiovascular Diseases based on their age, sex, blood pressure and otherwise healthy condition without chronic medication. They were interviewed semistructurally by a psychiatrist who was unaware of their blood pressure status. Eleven hypertensives and five normotensives (p less than 0.05) had experienced considerable traumas in childhood, e.g. death of a parent, psychotic parent, separation from one or both parents, or beating by an alcoholic father. The hypertensives had fewer siblings and fewer sons than the normotensives (p less than 0.05). The normotensives were better educated; 12 had finished at least 12 yr in school as opposed to one hypertensive (p less than 0.01). The normotensives' parents (p less than 0.05) and spouses (p less than 0.001) were better educated than the hypertensives'. The normotensives' yearly income was higher (p less than 0.05). The hypertensives showed more Type A behaviour patterns (p less than 0.05) and lower Spielberger State Curiosity (p less than 0.05). Although the groups were small, they were rigorously characterized. These results therefore suggest that middle-aged men with essential hypertension have more childhood traumas and lower educational and income levels and that these social characteristics are associated with Type A behaviour patterns. The study favours a psychosocial understanding of the pathogenesis of essential hypertension.

Arousal↗

PubMed1990

Increased erythrocyte magnesium in never treated essential hypertension.

In the present study we aimed at evaluating the intracellular concentrations of magnesium, potassium and sodium in 50-year-old, otherwise healthy white men with never treated, essential hypertension (n = 12) and in normotensive control subjects (n = 12) matched for age, sex, race, height, weight and smoking habits. Intraerythrocyte magnesium was significantly increased in the hypertensive group (P less than .001) and correlated positively and significantly to blood pressure in the total group (P less than .01). The intracellular potassium to sodium ratio tended to be lower in the hypertensive group (P less than .05). Thus, the present study supports increased intracellular magnesium probably unrelated to intracellular potassium-sodium imbalance in never treated, essential hypertension.

Blood Pressure↗

PubMed1990

Increased erythrocyte magnesium content in essential hypertension.

The present study aimed at testing the hypothesis of decreased erythrocyte magnesium content and magnesium deficiency in essential hypertension. Atomic absorption was used to measure the erythrocyte content of total magnesium in 50-year-old otherwise healthy white males with essential hypertension (n = 12, blood pressure (mean +/- SE) 155 +/- 4/109 +/- 2 mmHg) that had never been treated and in normotensive control subjects (n = 12, blood pressure 128 +/- 2/88 +/- 1 mmHg) matched for age, sex, race, height, weight and smoking habits. The erythrocyte magnesium content was significantly increased in the hypertensive group (2.266 +/- 0.063 vs 1.903 +/- 0.069 mmol/l erythrocytes, p less than 0.001). No significant difference between the groups was detected for serum concentration or the 24-h urinary excretion of magnesium. In conclusion, the present study indicates increased rather than decreased erythrocyte content of magnesium in 50-year-old white males with 'never-treated', essential hypertension. Magnesium deficiency is, therefore, unlikely in this subset of critically selected and matched hypertensive patients.

Erythrocytes↗

PubMed1990

Lipid effects of antihypertensive drugs.

Despite the well-established correlation between coronary heart disease (CHD) and hypertension, conventional antihypertensive therapy with diuretics and beta-adrenergic blockers has failed to provide protection against CHD. A possible explanation for this failure is the unfavourable effect such drugs have on lipid metabolism. To compare the lipid profiles of commonly used antihypertensive drugs, a survey was made of selected studies from the literature. Diuretics and selective and nonselective beta-blockers were found to have adverse effects on blood lipids. Beta-blockers with intrinsic sympathomimetic activity, labetalol, methyldopa, calcium channel blockers and ACE-inhibitors are lipid neutral, whereas alpha-adrenergic blockers seemed to have a favourable effect on lipid metabolism. Controlled clinical trials with drugs that have no adverse effects on lipid metabolism are needed to establish the long-term clinical importance of such agents.

Antihypertensive Agents↗

PubMed1989

Arterial plasma norepinephrine correlates to blood pressure in middle-aged men with sustained essential hypertension.

Increased plasma catecholamine levels assessed from the venous blood have been found in a number of studies of younger patients with essential hypertension, but hypertensive-normotensive differences could not easily be demonstrated in subjects above 40 years of age. For several reasons, measurement of arterial plasma catecholamines may be a more sensitive tool for the detection of hypertensive-normotensive differences. The present study therefore aimed at examining both venous and arterial plasma catecholamines in a group of white men, all 50 years of age, with never-treated, established essential hypertension (n = 61, blood pressure 165 +/- 2/112 +/- 1 mm Hg, means +/- SE) and comparing them with a similar group of normotensive men (n = 51, blood pressure 128 +/- 1/85 +/- 1 mm Hg). Arterial and venous plasma epinephrine, heart rate, and body weight were significantly elevated in the hypertensive group. Plasma norepinephrine was similar between the groups in the venous blood, whereas in the arterial blood the values in hypertensive subjects were moderately, but significantly increased (p less than 0.03). However, stepwise multiple regression analysis suggested arterial plasma norepinephrine was the only significant independent explanatory variable of raised blood pressure in the hypertensive group (r = 0.51, t = 4.05, p = 0.0002). Such a relationship was not found in the normotensive group. Thus based on measurements in arterial blood, we conclude that plasma norepinephrine, representing sympathetic tone, may be an important pathogenetic factor for high blood pressure in middle-aged men with established hypertension.

Blood Pressure↗

PubMed1989

Prevention of coronary heart disease: some results from the Oslo secondary and primary intervention studies.

The increase in cardiac disease [fatal and nonfatal myocardial infarction (MI), and sudden death] in the post-war years in Norway, after the much lower incidence during the war, that coincided with high and low fat intakes, respectively, led to a trial in Oslo to determine whether lowering dietary fat intake would favorably influence occurrence of coronary heart disease (CHD). Dietary modification, which lowered serum cholesterol of men who had suffered a first-time MI, showed decreased reinfarction incidence and cardiac deaths as compared with a comparable group of controls. Another study of normotensive high-risk men (on the basis of serum cholesterol and smoking habits) showed that dietetic measures can be useful in preventing CHD.

Adult↗

PubMed1989

Serum triglycerides as an independent risk factor for death from coronary heart disease in middle-aged Norwegian men.

The relation between nonfasting serum triglycerides and death from coronary heart disease was studied in 37,546 men aged 35-49 years who were examined during 1972-1977 in four counties in Norway. During an average follow-up period of nine years, 369 deaths from coronary heart disease occurred. In univariate analysis, log(triglycerides) were a weak, but statistically significant predictor of coronary death in the age groups 40-44 and 45-49 years. Within-area analysis showed that a high triglyceride area represented no extreme. When other coronary risk factors were adjusted for, log(triglycerides) remained a significant independent predictor at ages 45-49 years and at higher levels of serum cholesterol. The predictive strength of serum cholesterol was largely the same whether log(triglycerides) were taken into account or not, whereas the predictive strength of log(triglycerides) depended on whether serum cholesterol was accounted for. The strength of coronary death prediction of the logarithm of serum triglycerides was hardly greater than might be explained by the fact that triglycerides are an indicator of the usual cholesterol level of the subject.

Adult↗