Sven-Eric Lindell

Ten year cerebrovascular morbidity and mortality in 68 year old men with asymptomatic carotid stenosis

Abstract Objective: To study the natural course of carotid artery stenosis detected by ultrasonography. Design: Prospective cohort study. Baseline examination in 1982-3 included ultrasound examination of carotid arteries, measurement of anklebrachial blood pressure index, and detection of atrial fibrillation by 24 hour ambulatory electrocardiography. Setting: Malmo, a city in southern Sweden with 230000 inhabitants. Subjects: 470 men aged 68 years randomly selected from the population. Main outcome measures: Incidence of stroke and transient ischaemic attack and all cause mortality during 10 years of follow up in relation to carotid stenosis, leg artery disease (ankle-brachial blood pressure index below 0.9), and atrial fibrillation. Results: Fifty men had a stroke; six of these were haemorrhagic. Another 11 had a transient ischaemic attack. Eighteen of the men with carotid stenosis (21.6 events/1000 person years) and 43 of the men with normal carotid arteries (14.8 events/1000 person years) had a stroke or transient ischaemic attack (P=0.188). Men with atrial fibrillation had an increased rate of cerebrovascular events (36.7/1000 person years (P=0.048). The highest rate was found in men with asymptomatic disease of the leg arteries (38.6/1000 person years) (P<0.001). The increased risk of stroke or transient ischaemic attack in this group remained after multivariate analysis (relative risk 2.0; 95% confidence interval 1.1 to 3.7). Conclusions: In this cohort carotid stenosis was not associated with an increased risk of stroke. Part of this lack of association was explained by the high mortality from ischaemic heart disease in men with severe stenosis. Twenty seven of the 61 cerebrovascular events, however, occurred in men who had normal carotid arteries, normal ankle pressure, and no atrial fibrillation. Key messages Key messages Asymptomatic atherosclerosis in carotid and leg arteries is a common occurrence among elderly people Both conditions were found to be associated with an excess cardiovascular mortality Compared with leg artery disease, asymptomatic carotid stenosis was not found to be associated with an increased risk of stroke Assessment of peripheral atherosclerotic disease by measurement of arm and ankle blood pressure is a useful method for identifying patients with an increased risk of stroke

Risk factors for carotid artery senosis: An epidemiological study of men aged 69 years

Four hundred and seventy-eight men born in 1914 and residing in the city of Malmö, Sweden, underwent ultrasonic Doppler examination of the carotid arteries in 1982/83. The known risk factors for vascular disease--blood pressure, lipids, glucose, hematocrit, alcohol consumption and Body Mass Index were also measured. A moderate stenosis (diameter reduction 30-59%) of the internal carotid artery was found in 95 men (20%); 15 men (3%) had a greater than or equal to 60% stenosis of the internal carotid artery, while 7 (1.5%) had complete unilateral occlusion. Smoking was found to be significantly related to severe carotid artery disease. There was also a significant correlation between maximum flow velocity in the internal carotid artery and triglycerides. Those quitting smoking before the age of 50 had the same incidence of internal carotid artery disease as non-smokers, while those quitting later in life had a slightly higher incidence than life-long smokers.

Effects of a health screening on mortality and causes of death in middle-aged men, A prospective study from 1970, to 1974 of men in Malmö, born 1914.

All men born in even-numbered months in 1914 and domiciled in Malmö were invited in 1969 to participate in an investigation regarding risk factors for cardiovascular disease. Individuals with a blood pressure of 165/110 and over were treated and a sub-sample of heavy smokers were later invited to take part in a quit-smoking project. During the following five year period total and cause-specific mortality in the examined group was compared with corresponding data for men born in uneven months in 1914. Mortality in the examined cohort was lower than among controls and differed significantly from that in the control group with regard to cardiovascular mortality.

Plethysmographic pulse wave amplitude and future leg arteriosclerosis

A low pulse wave amplitude during calf plethysmography at 55 years of age was previously found to be associated with an increased mortality and incidence of myocardial infarction. In order to test the hypothesis that a low pulse wave amplitude is associated with an increased risk of future leg atherosclerosis as well, we have studied the relationship between a low ankle-brachial pressure index (ABPI; < 0.9) at 68 years of age and the pulse wave amplitude at 55 years of age in that same cohort. The prevalence of a low pulse wave amplitude (< or = 5 mm; lowest quintile) among men with a low ABPI (42%) was more than twice as high as it was among men who had a normal ABPI (19%) (P < 0.001). No association was found between a low ABPI and the plethysmographically recorded leg blood flow at 55 years of age. A low pulse wave amplitude might reflect early symptom-free arteriosclerosis, or age-dependent non-arteriosclerotic loss of vessel wall elasticity. The relationship between a low pulse wave amplitude and a low ABPI remained when controlling for smoking, hypertension and hyperlipidaemia. It is concluded that pulse wave measurement by plethysmography contributes information to improve leg atherosclerotic risk assessment in individuals exposed to known risk factors.

Intermittent Claudication and Hypertension. Ankle Pressure and Walking Distance in Patients with Well-Treated and Non-Treated Hypertension

Leg blood flow is directly related to the perfusion pressure and inversely related to the peripheral resistance. Hence, one would assume that in patients with a constantly increased arterial resistance in the legs due to arteriosclerosis a lowered systemic blood pressure would lead to a reduced leg blood flow. In fact, there are recommendations to use anti-hypertensive treatment with great care in patients with intermittent claudication in order not to further reduce their impaired arterial leg blood flow. In patients with rest pain and gangrene there have even been recommendations to use blood pressure increasing therapy in order to improve the reduced arterial leg blood flow.2 2

Features of carotid artery flow velocity in healthy subjects and consequences for evaluating stenosis in the internal carotid artery

C-W-Doppler analysis of flow velocity in the carotid arteries was performed in 98 healthy volunteers, age 16-74 years, 49 of each sex, and in 23 subjects with carotid disease. Maximum frequency shift (MFS) and total band-width in the healthy proximal internal carotid artery were negatively correlated to age in both sexes (p less than 0.001). MFS was lower in the normal proximal internal carotid artery than in the common carotid artery in both sexes. Minimum frequency shifts were more often, and more negative in the proximal than in the distal part of the internal carotid artery (p less than 0.001 in men and less than 0.01 in women) and still more so in the proximal part of the pathological internal carotids as compared with the normal ones (p less than 0.001). The computer-fitted regression between MFS and the degree of angiographic stenosis in the subjects with carotid artery disease was nearly identical with the mathematically calculated relationship for an ellipsoid stenosis. There is reason to believe that the degree of area stenosis calculated from frequency shift and predicted normal values gives a more true interpretation of functional stenosis than angiography, while the latter might be superior for evaluating vascular patho-anatomy, giving information also about intrathoracic and intracranial vessels, which also is important for evaluating patients with TIA and related symptoms.

Risk factors for premature death in men 56-60 years old. A prospective study of men born 1914, living in Malmö, Sweden.

In a five-year follow-up of a random sample of men aged 55 the association between risk factors and premature death was analysed. The overall mortality in five years was 5.8%. The mortality among the smokers was 8%; among non-smokers 2%. Of 16 cancer deaths all were smokers except one who was an ex-smoker. In spite of treatment of hypertension (>165/110 mmHg) there was an association between high blood pressure and premature death, particularly when cause of death was cardiovascular disease. There was no association between premature death and serum cholesterol, serum triglycerides or physical activity. The study is based on 703 men, of whom 41 died. The autopsy frequency was 93%. Only 3 men (0.4%) were lost to follow-up.

Detection, Treatment and Follow-up of Hypertension in a Community Sample of 55-Year-Old Men

In connection with a population study including 703 randomly selected 55-year-old men, 20 men with the highest blood pressure were selected for a careful follow-up and treatment for 1 year. Controls without hypertension were randomly selected from the remainder of the same population. Electrocardiogram at rest and in connection with an exercise test, changes in fundus oculi, orthostatic tests, peripheral arterial blood flow, chemical analyses and other variables were recorded on three occasions during the observation year. Drug treatment was standardized. Basic treatment was induced with polythiazide, which normalized the blood pressure in the majority of the hypertensive cases. The most striking findings in the hypertensive group before treatment were, besides the high blood pressure at rest, high blood pressure during exercise, an increased peripheral blood-flow through the calves, and an increased heart-rate. During treatment, the blood pressure were selected for a careful follow-up and blood-flow were almost “normalized”; the heart-rate remained elevated. The investigation shows that it is quite easy to achieve adequate reduction of blood pressure in hypertension among middle-aged men, as found in the “real world” outside the hospital. The main problem today is not to normalize the blood pressure but rather to detect hypertension and to maintain the therapy for several years. Hypertension is considered to be the cardiovascular risk factor that is probably most amenable to preventive approaches to public health.

Pulmonary arterial-venous differences in lipids and lipid metabolites.

This study was designed to reevaluate the effectiveness of the lungs in taking up lipids from the blood, and to establish whether or not the blood triglycerides so extracted are metabolized. 8 normal human males were studied. With the subject fasting and supine, a percutaneous catheter was placed in the pulmonary artery, another in the superior vena cava, and a third in the brachial artery. Samples of mixed venous and arterial blood were drawn by syringe from the pulmonary and brachial arteries, respectively. Infusion of a triglyceride emulsion (20% Intralipid) into the superior vena cava was begun at 4.7 ml/min. After 12 min of infusion, mixed venous and arterial samples were taken and infusion was discontinued. 15 min following termination of infusion, blood samples were again drawn. Analysis showed the lungs to be retaining about 25% of available triglyceride. Cholesterol concentration was unaffected. Arterial-venous differences in glycerol and free fatty acid were insignificant, suggesting no metabolism of triglyceride by lungs. The lungs apparently serve as a mechanical screen to triglyceride.

The Oral Glucose Tolerance Test in Men Under 55 Years of Age With Intermittent Claudication

Blood glucose at sixty, ninety, and one hundred twenty minutes after a stand ardized oral glucose load was compared in healthy middle-aged men and pa tients with intermittent claudication. No difference was found when the authors compared blood glucose at zero and sixty minutes. At both ninety and one hun dred twenty minutes, however, they found a relative hypoglycemia in patients with peripheral arteriosclerotic disease in an early stage.