Analysis of risk factors for stroke in a cohort of men born in 1913

Do hemophilia A and von Willebrand disease protect against carotid atherosclerosis? A comparative study between coagulopathics and normal subjects by means of carotid echo-color Doppler scan

Atherosclerosis is a multifactorial disease caused by genetic and environmental factors with important clinical sequelae. The aim of this study was to evaluate the degree of carotid atherosclerosis by echo-color Doppler scan in a group of patients affected by hemophilia A and von Willebrand disease versus a group of normal subjects apparently free of atherosclerotic risk factors. All coagulopathics and normal patients who came to our Internal Medicine Department (Padua Hospital) underwent physical exam, blood analysis, standard electrocardiogram, chest x-ray, echo-color Doppler scan, and a thorough history. We examined 156 subjects, 76 coagulopathics (46 men, 30 women) and 77 normals (37 men, 40 women). Coagulopathics were affected by hypertension in 28.9% of cases, diabetes mellitus in 6.5%, dislipidemia in 17.1%, smoke in 39.4%, and obesity in 36.8% (p < .05). Echo-color Doppler scan revealed carotid plaques in 27.2% of control patients versus 13.1% of coagulopathics (p < .05). Hemophilics and subjects with von Willebrand disease with a more serious illness had fewer plaques than those with lighter defects. Coagulopathics showed 23.6% of the plaques we revealed on the whole, versus 76.3% of control subjects (p < .01), with a lighter degree of stenosis (p < .01). Our data demonstrate that patients with hemophilia A and von Willebrand disease have fewer carotid plaques and a smaller degree of carotid stenosis than normal subjects of the same sex and age. These data seem to strengthen the hypothesis that blood coagulation defects may allow protection against carotid atherosclerosis and its sequelae.

Stress-induced cortisol, mood, and fat distribution in men

OBJECTIVE

A previous study in our laboratory (Moyer et al., Obes Res. 1994;2:255-62 found that, in response to uncontrollable laboratory stress, women with a high waist-to-hip ratio (WHR) had higher cortisol reactivity, poorer coping skills, and lower anger responses than women with low WHR. We aimed to compare high WHR men's stress responses to these women.

RESEARCH METHODS AND PROCEDURES

The current study examined cortisol reactivity and psychological data of 27 healthy high WHR men exposed to the same laboratory challenges as the women from our previous study. Men's data are discussed in relation to that of the high and low WHR women.

RESULTS

Men responded to the stress with increases in both cortisol and blood pressure. In comparison with the high and low WHR women, men had significantly higher total cortisol on the stress day. However, when comparing a sub-sample of men and women matched in WHR's, differences in cortisol secretion were greatly diminished and no longer significant. In addition, men had higher desire for control than both high and low WHR women, and lower mood reactivity than low WHR women. Despite the lower mood reactivity of high WHR groups, the high mood reactors among the high WHR women, and to a lesser extent, men, tended to have higher cortisol reactivity.

DISCUSSION

These results suggest that the psychological differences and greater exposure to cortisol observed among the high WHR men and women may have played a role in contributing to their greater abdominal fat depots.

Stroke risk factors and development of collateral flow in carotid occlusive disease

BACKGROUND AND PURPOSE

Blood flow through collateral vessels compensates for reduced blood flow through stenotic or occluded extracranial carotid arteries. Previous studies have shown that extent of collateral flow influences likelihood of stroke and its outcome. Here we analyzed the relationship between stroke risk factors (hypertension, coronary artery disease, diabetes mellitus, tobacco smoking and hypercholesterolemia) and number of patent intracranial collaterals detected by transcranial Doppler ultrasonography.

SUBJECTS AND METHODS

We studied 182 patients with various degrees of angiography proven unilateral stenosis of the internal carotid artery. Contribution of the anterior and posterior communicating arteries to the perfusion of the cerebral hemisphere on the side of the stenosis or occlusion was evaluated by a series of compression tests performed during continuous insonation of the middle cerebral artery. The number of detected collateral vessels was correlated with analyzed stroke risk factors.

RESULTS

Subjects with stenosis more than 75% or occlusion of the internal carotid artery had a higher frequency of two major intracranial collateral vessels (P< or =0.01 and P< or =0.001, respectively). Hypertensive patients with stenosis more than 75% or total carotid occlusion were more likely to have only a single collateral vessel than patients without hypertension (P< or =0.01 and P< or =0.05, respectively). Other risk factors did not influence the patency of preformed collateral vessels.

CONCLUSIONS

Hypertension hindered the development of preformed intracranial collateral vessels in our patients with carotid occlusive disease.

Methylenetetrahydrofolate reductase gene polymorphism and ischemic stroke in Japanese

Hyperhomocyst(e)inemia has been identified as an independent risk factor for atherosclerotic and thromboembolic diseases such as coronary artery disease, cerebral artery disease, and venous thrombosis. Recently, the alanine/valine (A/V) gene polymorphism of 5,10-methylenetetrahydrofolate reductase (MTHFR), one of the key enzymes that catalyzes the remethylation of homocysteine, was reported. The VV genotype is correlated with increased plasma homocyst(e)ine levels as a result of the reduced activity and increased thermolability of this enzyme. In this study, we examined the association between the V allele of the MTHFR gene and ischemic stroke in an elderly Japanese population. The diagnosis of cerebral infarction of all study patients was confirmed by CT of the brain. The MTHFR genotype was analyzed by polymerase chain reaction followed by HinfI digestion. In 256 stroke patients and 325 control subjects, the frequencies of the V allele were 0.45 and 0.32, respectively. The odds ratios and 95% confidence intervals adjusted for the other risk factors were, respectively, 1.51 (1.02 to 2.23) for the AV genotype and 3.35 (1.94 to 5.77) for the VV genotype compared with the AA genotype. Both of these effects were statistically significant (P=0.041 and P<0.001, respectively). In patients with multiple infarcts in particular, the allele frequency of the V mutation was 0.56, and the association between the V allele and stroke was highly significant. Plasma homocyst(e)ine levels were significantly higher in patients with the VV genotype than in patients with the AA or AV genotype, especially those with low plasma folate levels. The V allele of the MTHFR gene was significantly associated with cerebral infarction in an elderly Japanese population in a codominant manner. The VV genotype may contribute to risk for ischemic stroke through a predisposition to increased plasma homocyst(e)ine levels, and dietary folate supplementation may be of benefit, particularly to patients with this genotype.

Incidence and risk factors for stroke in an occupational cohort: the PROCAM Study. Prospective Cardiovascular Muenster Study

BACKGROUND AND PURPOSE

The purpose of this study was to assess the incidence of stroke and the magnitude of classic stroke risk factors in an occupational cohort of white-collar and blue-collar workers.

METHODS

We studied a prospective cohort of 12 866 male employees, aged 30 to 65 years, in 52 companies in northwestern Germany, with an average follow-up of 7.2 years. Participants were free of self-reported stroke, transient ischemic attack, and myocardial infarction at baseline. Physical examination, blood tests, and a face-to-face interview to assess presence of various risk factors were performed at the workplace. Follow-up was done by standardized mailed questionnaire. Main outcome measure was first stroke occurrence.

RESULTS

Overall stroke incidence was 42.4 per 100000 person-years, increasing from 10.1 per 100000 person-years in the age category 30 to 39 years to 33.6, 80.6, and 159.2 per 100000 person-years in the age categories 40 to 49, 50 to 59, and 60 years and older, respectively. After adjustment for potential confounders, the relative risks of total stroke associated with systolic blood pressure < or = 120, 121 to 140, and > or = 141 mm Hg were 1.00 (reference), 2.99 (95% confidence interval, 0.85 to 10.49), and 5.56 (1.56 to 19.88). The risks associated with smoking status of never/past, < or = 20 cigarettes per day, and >20 cigarettes per day) were 1.00 (reference), 1.65 (0.62 to 4.42), and 3.56 (1.78 to 7.15), respectively. A history of hypertension at baseline (yes versus no) was independently associated with a relative risk of 2.37 (1.20 to 4.71) for total stroke and a history of diabetes mellitus (yes versus no) with a risk of 2.21 (1.00 to 4.87). A comparison of risk factor levels with a general population study revealed only small differences.

CONCLUSIONS

This occupational cohort had a 2-fold lower stroke incidence than that observed in cohorts of the general population. In the absence of a strong healthy-worker effect, moderate differences in behavioral risk factors and a higher treatment rate for hypertension contribute to the explanation of this favorable stroke incidence.

Risk factors for stroke and type of stroke in persons with isolated systolic hypertension. Systolic Hypertension in the Elderly Program Cooperative Research Group

BACKGROUND AND PURPOSE

We sought to determine risk factors for stroke and stroke type in persons with isolated systolic hypertension (ISH).

METHODS

We performed proportional hazards analyses of data from the Systolic Hypertension in the Elderly Program, a double-blind, randomized, placebo-controlled trial of 4736 persons aged > or =60 years with ISH (systolic blood pressure, 160 to 219 mm Hg; diastolic blood pressure, <90 mm Hg). One treatment group received chlorthalidone (12.5 to 25 mg/d) with step-up to atenolol (25.0 to 50.0 mg/d) or reserpine (0.05 to 0.10 mg/d), if needed. The other treatment group received matching placebo. The main outcome measures were stroke, stroke or transient ischemic attack [TIA], and stroke types: ischemic (including lacunar, atherosclerotic, and embolic) and hemorrhagic.

RESULTS

During an average follow-up of 4.5 years, 384 strokes or TIAs and 262 strokes (including 217 ischemic, 66 lacunar, 26 atherosclerotic, and 25 embolic strokes) were documented. In multivariate analyses, placebo treatment, older age, smoking, history of diabetes, higher systolic blood pressure, lower HDL cholesterol, and ECG abnormality were significantly associated (P<0.05) with increased incidence of stroke or TIA, stroke, or ischemic stroke. Greater lacunar stroke risk was significantly related to placebo treatment, older age, history of diabetes (relative risk [RR] = 3.03; 95% confidence interval [CI], 1.70 to 5.40), and smoking (RR = 3.04; 95% CI, 1.73 to 5.37). Greater atherosclerotic and embolic stroke risk were significantly related to presence of carotid bruit (RR = 5.75; 95% CI, 2.50 to 13.24) and older age (RR = 1.65 per 5 years; 95% CI, 1.25 to 2.18), respectively.

CONCLUSIONS

In older persons with ISH, history of diabetes and smoking are important risk factors for lacunar stroke, whereas carotid bruit and age are important risk factors for atherosclerotic and embolic stroke, respectively.

Risk factors for ischemic stroke: Dubbo Study of the elderly

BACKGROUND AND PURPOSE

One in 10 deaths in Australia is due to stroke. The predictors of ischemic stroke have not been well defined, although hypertension, atrial fibrillation, and previous stroke have been consistently reported. We report on 98 months' follow-up in a prospective study of cardiovascular disease in the Australian elderly, the Dubbo Study.

METHODS

The cohort, first examined in 1988, was composed of 2805 men and women 60 years and older. The prediction of ischemic stroke by potential risk factors was examined in a Cox proportional hazards model, after linkage to hospital and death records.

RESULTS

Three hundred six men and women manifested an ischemic stroke event (ICD-9-CM 433 to 437), and 95 subjects suffered a fatal stroke event. In the multivariate model, the significant independent predictors of stroke were advancing age, female sex (48% lower risk), being married (30% lower risk), prior history of stroke (227% higher risk), use of antihypertensive drugs (37% higher risk), belonging to the highest category of blood pressure reading (67% higher risk), presence of atrial fibrillation (58% higher risk), HDL cholesterol (36% lower risk for each 1-mmol/L increment), impaired peak expiratory flow (77% higher risk for tertile I than for tertile III), physical disability (59% higher risk), and depression score (41% higher risk for tertile III than for tertile I).

CONCLUSIONS

These findings suggest that morbidity and mortality associated with ischemic stroke can be predicted by various clinical indicators, some of which may be amenable to intervention. The matters of impaired peak expiratory flow, depression score, and ischemic stroke require further study.

Increased oxygen extraction fraction is associated with prior ischemic events in patients with carotid occlusion

BACKGROUND AND PURPOSE

The purpose of our study was to investigate the relationship between misery perfusion (increased oxygen extraction fraction, OEF) and baseline risk factors in patients with carotid occlusion.

METHODS

One-hundred seventeen patients with atherosclerotic carotid occlusion were studied prospectively by clinical evaluation, laboratory testing, and positron emission tomography (PET). PET measurements of cerebral blood flow (CBF), cerebral blood volume (CBV), and OEF were made on enrollment in the study. Increased ipsilateral OEF was identified by comparison with 18 normal control subjects. Twenty-five baseline clinical, epidemiological, and arteriographic risk factors were assessed on study entry. Student t tests, chi(2) tests, and Fisher exact tests with Bonferroni correction were used to assess statistical significance (P<.05).

RESULTS

Of 117 patients, 44 had increased OEF distal to the occluded carotid and 73 had normal OEFs. Thirty-nine of the 81 patients with prior ipsilateral ischemic symptoms had high OEFs (42%), whereas only 5 of the 31 asymptomatic patients had high OEFs (16%, P<.001). All of the other baseline risk factors were similar between the two groups of patients.

CONCLUSIONS

Investigations of the relationship between hemodynamic factors and stroke risk must take into account the lower frequency of hemodynamic abnormalities in asymptomatic patients.

The risk of hospitalization for ischemic stroke among older adults

OBJECTIVES

The purpose of this study was to identify risk factors for stroke and to estimate their relative importance in a large, nationally representative sample of very old men and women.

METHODS

The study was designed as a secondary analysis of the Longitudinal Study on Aging. Baseline (1984) in-person interview data were linked to Medicare hospitalization records for 1984 to 1991. Participants were 6,071 noninstitutionalized adults 70 years old or older at baseline. Hospitalization for ischemic stroke was defined as having one or more episodes with a primary discharge diagnosis containing ICD-9-CM codes of 433.0-434.9, 436, and 437.0-437.1. Multivariable proportional hazards regression was used to estimate the risks associated with previously identified epidemiologic factors.

RESULTS

Five hundred and three persons (8.3%) had at least one primary discharge diagnosis of ischemic stroke. In descending order of importance-based on the partial r statistics associated with their adjusted hazards ratios (AHRs), the salient risk factors were having a previous history of stroke (AHR = 2.86), age (AHR = 1.04 per year), diabetes (AHR = 1.78), male gender (AHR = 1.42), lower body limitations (AHR = 1.09 per limitation), arthritis (AHR = 0.74), hypertension (AHR = 1.29), and poverty (AHR = 1.33).

CONCLUSION

Patients presenting with the high risk factors identified in this study should be considered for further evaluation and monitoring. Current protocols for the therapeutic management of these higher risk patients should be considered, and compliance should be encouraged.

Platelet glycoprotein receptor IIIa polymorphism P1A2 and ischemic stroke risk: the Stroke Prevention in Young Women Study

BACKGROUND AND PURPOSE

Platelet glycoprotein IIb/IIa (GpIIb-IIIa), a membrane receptor for fibrinogen and von Willebrand factor, has been implicated in the pathogenesis of acute coronary syndromes but has not been previously investigated in relation to stroke in young adults.

METHODS

We used a population-based case-control design to examine the association of the GpIIIa polymorphism P1A2 with stroke in young women. Subjects were 65 cerebral infarction cases (18 patients with and 47 without an identified probable etiology) 15 to 44 years of age from the Baltimore-Washington region and 122 controls frequency matched by age from the same geographic area. A face-to-face interview for vascular disease risk factors and a blood sample for the P1A2 allele and serum cholesterol were obtained from each participant. Logistic regression was used to estimate the odds ratio for one or more P1A2 alleles after adjustment for other risk factors.

RESULTS

Among cases and controls, the prevalence rates of one or more P1A2 alleles were 21% and 22% among blacks and 36% and 28% among whites, respectively. This genotype was significantly associated with hypertension only in black control subjects but otherwise not with any of the established vascular risk factors. The adjusted odds ratio for cerebral infarction of one or more P1A2 alleles was 1.1 (confidence interval [CI], 0.6 to 2.3) overall, 0.5 (CI, 0.1 to 7.1) among blacks, and 1.4 (CI, 0.5 to 3.7) among whites. For the cases with an identified probable etiology, the corresponding odds ratios were 3.0 (CI, 0.9 to 10.4) overall, 0.7 (CI, 0.1 to 7.1) among blacks, and 12.8 (CI, 1.2 to 135.0) among whites.

CONCLUSIONS

No association was found between the P1A2 polymorphism of GpIIIa and young women with stroke. However, subgroup analyses showed that the P1A2 polymorphism of GpIIIa appeared to be associated with stroke risk among white women, particularly those with a clinically identified probable etiology for their stroke. Further work with an emphasis on stroke subtypes and with multiracial populations is warranted.

Atrial fibrillation as a risk factor for stroke: a retrospective cohort study of hospitalized Medicare beneficiaries

OBJECTIVES

This study examined the relationship between atrial fibrillation and (1) stroke and (2) all-cause mortality.

METHODS

All eligible Medicare patients older than 65 years of age hospitalized in 1985 were followed up for 4 years. Kaplan-Meier and Cox proportional hazards models were used for assessment of risk of stroke and mortality.

RESULTS

A total of 4,282,607 eligible Medicare patients were hospitalized in 1985. The mean age was 76.1 (+/- 7.7) years; 58.7% were female; 7.2% were Black; and 8.4% had a diagnosis of atrial fibrillation. During the follow-up period, 66,063 patients (32.6/1000 person-years) developed nonembolic stroke and 7285 (3.6/1000 person-years) developed embolic stroke. After adjustment for age, race, sex, and comorbid conditions, atrial fibrillation remained a significant risk factor for both nonembolic stroke (relative risk [RR] = 1.56) and embolic stroke (RR = 5.80) and for mortality (RR = 1.31). Approximately 4.5% of nonembolic and 28.7% of embolic strokes among hospitalized Medicare patients aged 65 years and older were attributable to atrial fibrillation.

CONCLUSIONS

This study demonstrates that atrial fibrillation is associated with an appreciable increase in the risk of stroke (both embolic and nonembolic) and in the risk of mortality from all causes.

Risk factors for ischemic stroke in a Russian community: a population-based case-control study

BACKGROUND AND PURPOSE

This study was conducted to determine the risk factors for ischemic stroke in a defined Russian population.

METHODS

Our data are based on a population-based case-control study of 237 patients with first-ever ischemic stroke and 237 age- and sex-matched controls. Logistic regression methods for matched pairs were used to estimate the relative risk for the variables studied.

RESULTS

In a multivariate analysis, hypertension, left ventricular hypertrophy on electrocardiography, ischemic heart disease, mitral valve disease, current cigarette smoking, and high body mass index were significant and independent risk factors for ischemic stroke in this Russian community.

CONCLUSIONS

The significant risk factors for ischemic stroke in Novosibirsk are similar to those from other populations and cohorts. This study, the first of stroke risk factors in Russia, has implications for clinical practice and the planning of stroke prevention in the population.

Risk factors for microangiopathy-related cerebral damage in the Austrian stroke prevention study

Microangiopathy-related cerebral damage (MARCD) represents a common incidental MRI observation in the elderly. The risk factors of such findings are widely unknown. We therefore performed MRI in 349 randomly selected volunteers (ages 50 to 70 years) without neuropsychiatric disease, and evaluated the association of MARCD with conventional and recently suggested cerebrovascular risk factors such as apolipoprotein E genotypes, plasma concentrations of essential antioxidants and anticardiolipin antibody titres. MARCD was defined as evidence of early confluent and confluent deep white matter hyperintensities and lacunes. It was present in 71 (20.3%) subjects. Individuals with MARCD were older than those without such findings (62.7 years vs 59.6 years; P=0.0001). They had a higher rate of arterial hypertension (45.1% vs 28.1%; P=0.006) and cardiac disease (50.7% vs 37.1%; P=0.04), higher systolic blood pressure readings at exam (144.4 mmHg vs 136.7 mmHg; P=0.004), and higher serum fibrinogen concentrations (327.1 mg/dl vs 292.5 mg/dl; P=0.001). Their levels of total cholesterol (217.6 mg/dl vs 231.2; P=0.009), apolipoprotein A-I (167.3 mg/dl vs 177.4 mg/dl, P=0.02), lycopene (0.17 micromol/l vs 0.24 micromol/l; P=0.003), retinol (1.91 micromol/l vs 2.10 micromol/l; P=0.02) and alpha-tocopherol (27.55 micromol/l vs 31.14 micromol/l; P=0.001) were significantly lower. Forward stepwise regression analysis created a model of independent predictors of MARCD with age entering first (odds ratio 2.01/10 years), fibrinogen second (odds ratio 2.45/100 mg/dl), alpha-tocopherol third (odds ratio 0.55/10 micromol/l), and arterial hypertension fourth (odds ratio 1.96). The association of MARCD with various treatable clinical conditions may have preventive implications.

Social inequality in coronary risk: central obesity and the metabolic syndrome. Evidence from the Whitehall II study

This report describes the social distribution of central obesity and the metabolic syndrome at the Whitehall II study phase 3 examination, and assesses the contribution of health related behaviours to their distribution. Cross-sectional analyses were conducted utilising data collected in 1991-1993 from 4978 men and 2035 women aged 39-63 years who completed an oral glucose tolerance test. There was an inverse social gradient in prevalence of the metabolic syndrome. The odds ratio (95% confidence interval) for having the metabolic syndrome comparing lowest with highest employment grade was: men 2.2 (1.6-2.9), women 2.8 (1.6-4.8). Odds ratios for occupying the top quintile of the following variables, comparing lowest with highest grade, were, for waist-hip ratio: men 2.2 (1.8-2.8), women 1.6 (1.1-2.4); post-load glucose: men 1.4 (1.1-1.8), women 1.8 (1.2-2.6); triglycerides: men 1.6 (1.2-2.0), women 2.2 (1.5-3.3); fibrinogen: men 1.7 (1.4-2.3), women 1.9 (1.2-2.8). Current smoking status, alcohol consumption and exercise level made a small contribution (men 11%, women 9%) to the inverse association between socioeconomic status and metabolic syndrome prevalence. In conclusion, central obesity, components of the metabolic syndrome and plasma fibrinogen are strongly and inversely associated with socioeconomic status. Our findings suggest the metabolic syndrome may contribute to the biological explanation of social inequalities in coronary risk. Health related behaviours appear to account for little of the social patterning of metabolic syndrome prevalence.

Familial history of stroke and stroke risk. The Family Heart Study

BACKGROUND AND PURPOSE

Although familial history of stroke is generally perceived to be an important marker of stroke risk, very few epidemiological studies have been published to address this hypothesis. We sought to examine whether familial history of stroke is associated with the prevalence of stroke in the Family Heart Study, a National Heart, Lung, and Blood Institute-supported multicenter study of the familial, genetic, and nongenetic determinants of cardiovascular disease in populations.

METHODS

The personal and familial histories of stroke were assessed in 3168 individuals (probands) who were at least 45 years old and 29,325 of their first-degree relatives with the use of a standardized questionnaire.

RESULTS

The age-, ethnicity-, and sex-adjusted stroke prevalences were 4.8%, 4.9%, and 3.9% in probands with a positive familial, paternal, and maternal history of stroke, respectively, in comparison with 2.0% in probands without any positive familial history (P < .01). The age-, ethnicity-, and sex-adjusted odds ratios (95% confidence interval) of stroke were 2.00 (1.13, 3.54) for a positive paternal and 1.41 (0.80, 2.50) for a positive maternal history of stroke. Additional statistical adjustment for the proband's history of elevated cholesterol level, cigarette smoking status, history of coronary heart disease, hypertension, and diabetes did not alter the associations. A similar pattern was seen for African Americans and European Americans.

CONCLUSIONS

The increased risk of stroke among persons with a positive familial history of stroke compared with those without a familial history of stroke is consistent with the expression of genetic susceptibility, a shared environment, or both in the etiology of stroke.

Association between acute cerebrovascular ischemia and chronic and recurrent infection

BACKGROUND AND PURPOSE

We performed a case-control study to investigate whether chronic or recurrent respiratory, ear-nose-throat (ENT), and dental infections are risk factors for cerebrovascular ischemia.

METHODS

Using a standardized questionnaire we investigated past infectious diseases in 166 consecutive patients with acute cerebrovascular ischemia and in 166 age- and sex-matched nonstroke neurological patient controls. In subgroups, we performed standardized ENT (69 patients, 66 control subjects) and dental examinations including orthopantomography (66 patients, 60 control subjects). Dental status was determined by a total dental index (TDI) that reflects caries, periapical lesions, periodontitis, and other dental lesions and by an orthopantomography index (OPGI) that was assessed blinded.

RESULTS

Frequent (> or = 2 episodes in each of the 2 preceding years) or chronic bronchitis was associated with cerebrovascular ischemia in age-adjusted multiple logistic regression analysis (odds ratio, OR, 2.2; 95% confidence interval, CI, 1.04 to 4.6). Groups were not different in ENT examination. Patients tended to have a worse dental status (TDI: P = .070; OPGI: P = .062) and had more severe periodontitis (P = .047) and periapical lesions (P = .027) than control subjects. In age-adjusted multiple logistic regression analysis with social status and established vascular risk factors, poor dental status (TDI) was independently associated with cerebrovascular ischemia (OR, 2.6; 95% CI, 1.18 to 5.7).

CONCLUSION

Recurrent or chronic bronchial infection and poor dental status, mainly resulting from chronic dental infection, may be associated with an increased risk for cerebrovascular ischemia.

Parental history of cardiovascular disease and risk of stroke. A prospective follow-up of 14371 middle-aged men and women in Finland

BACKGROUND AND PURPOSE

Studies on risk factors for stroke have been less intensive than those for coronary disease. Only a few studies have addressed the question of the role of heredity in the occurrence of stroke. We analyzed whether a positive parental history of cardiovascular disease predicts the risk of stroke independently from other risk factors and whether the role of parental history varies by age and stroke subtypes.

METHODS

This study was a prospective follow-up of 14371 middle-aged men and women. A positive parental history of cardiovascular disease was defined as either stroke or coronary disease before the age of 60 years. The end point of the follow-up was an incident case of stroke. Multivariate analyses were performed with the Cox proportional hazards model.

RESULTS

The risk ratio of stroke after multifactorial adjustment (age, smoking, blood pressure, cholesterol, diabetes, and education) associated with a positive parental history of stroke was 1.89 (P = .004) in men and 1.80 (P = .007) in women. The association between parental history of stroke and the risk of stroke was stronger among subjects aged 25 to 49 years than among older subjects. Parental history of coronary disease was not associated with the risk of stroke in men, but in women it had a borderline significant association with the risk of ischemic stroke.

CONCLUSIONS

A positive parental history of stroke predicted the risk of stroke independently from the other risk factors.

Arterial Damage, Triglycerides, Apolipoprotein, and Lp-(a) Values in PVD Patients

The aim of the study was to provide a detailed apolipoproteic profile in stage II peripheral vascular disease (PVD) patients and to ascertain whether lower ankle/ arm pressure index (API) values were associated with a worse profile.

Apolipoproteins of 83 stage II PVD patients (average age 64.7 ± 9.3 years) were selected and compared with those of a group of 44 normal control subjects, similar in terms of age, sex, and smoking and eating habits. Neither PVD patients nor controls had ever received lipid-lowering agents or defined dietary treatment. A diagnosis of PVD was confirmed by an API of <0.85. Arteriopathic patients were also split into two groups, depending on their API values, similar in terms of age, sex and smoking habits: API values of one group (n = 38) were ≥0.6, those of the other group (n = 45) were <0.6. The following biohumoral parameters were considered: fasting glycemia, total cholesterol, triglycerides (TGs); high-density lipoprotein cholesterol (HDL-C); low density lipoprotein cholesterol (LDL-C), very low density lipoprotein cholesterol (VLDL-C), total cholesterol (TC)/HDL-C (TC/ HDL-C), Apoproteins (Apos) AI, AII, B, CII, CIII, and E; and lipoprotein a [Lp(a)].

HDL-C and Apo AI were lower ( p < 0.01), while TC/ HDL-C ratios, Apo B, and Apo CII were higher ( p < 0.01) in PVD patients compared with controls. The comparison between the two PVD groups with different API values showed higher blood TG and VLDL-C values for the patients with lower API values (p < 0.05), indicating a relationship between hypertriglyceridemia and greater arterial damage. Key Words: Peripheral arterial occlusive disease-Triglyceride-Lipoprotein a.

Predictors of stroke pattern in hypertensive patients

BACKGROUND AND PURPOSE

Hypertension is a recognized risk factor for stroke. However, it is not clear why hypertensive patients may have different types and causes of stroke.

METHODS

The possible role of coexisting factors was studied in 1057 patients with hypertension and first stroke admitted to a population-based stroke center. We used logistic regression analysis (multivariate and polychotomous) and the Lausanne Stroke Registry definitions of cerebral hemorrhage, cerebral infarction, lacunar infarction, cardioembolism and large artery disease.

RESULTS

Cerebral hemorrhage was not more frequent in these hypertensive patients (111/1057 = 10.5%) than in the total population of the registry (213/2145 = 10%). Cerebral infarction was associated with age above the median (69 years), diabetes, smoking history, family history of cardiac or cerebrovascular disease, hypercholesterolemia and previous TIA. In the ischemic group (n = 946), patients suffered from a lacunar infarction in 36% of the cases, large artery disease was present in 21% of them and cardioembolism in 14.5%. Large artery disease correlated with smoking history (odds ratio: 2.14; 95% confidence intervals: 1.55-2.95) and previous TIA (OR:1.96; 95% CI:1.39-2.75). Cardioembolism correlated with age over 69 years (OR:2.13; 95% CI:1.47-3.09). In patients with previous TIA and smoking history, large artery disease was presumed in 45% of the cases (vs 21%). Patients aged over 69, suffered a cardioembolic stroke in 29% of the cases (vs 14.5%). Lacunar infarction occurred in 49% of patients aged less than 70 years when no history of smoking or previous TIA was present (vs 36%).

CONCLUSION

The associations between hypertension, TIA, age and smoking history may partially explain why patients with hypertension are more likely to develop a cerebral hemorrhage, lacunar infarction, cardioembolic or a large artery disease stroke.

Epidemiology of stroke

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Impaired lung function and mortality risk in men and women: findings from the Renfrew and Paisley prospective population study

OBJECTIVE

To assess the relation between forced expiratory volume in one second (FEV1) and subsequent mortality.

DESIGN

Prospective general population study.

SETTING

Renfrew and Paisley, Scotland.

SUBJECTS

7058 men and 8353 women aged 45-64 years at baseline screening in 1972-6.

MAIN OUTCOME MEASURE

Mortality from all causes, ischaemic heart disease, cancer, hung and other cancers, stroke, respiratory disease, and other causes of death after 15 years of follow up.

RESULTS

2545 men and 1894 women died during the follow up period. Significant trends of increasing risk with diminishing FEV1 are apparent for both sexes for all the causes of death examined after adjustment for age, cigarette smoking, diastolic blood pressure, cholesterol concentration, body mass index, and social class. The relative hazard ratios for all cause mortality for subjects in the lowest fifth of the FEV1 distribution were 1.92 (95% confidence interval 1.68 to 2.20) for men and 1.89 (1.63 to 2.20) for women. Corresponding relative hazard ratios were 1.56 (1.26 to 1.92) and 1.88 (1.44 to 2.47) for ischaemic heart disease, 2.53 (1.69 to 3.79) and 4.37 (1.84 to 10.42) for lung cancer, and 1.66 (1.07 to 2.59) and 1.65 (1.09 to 2.49) for stroke. Reduced FEV1 was also associated with an increased risk for each cause of death examined except cancer for lifelong nonsmokers.

CONCLUSIONS

Impaired lung function is a major clinical indicator of mortality risk in men and women for a wide range of diseases. The use of FEV1 as part of any health assessment of middle aged patients should be considered. Smokers with reduced FEV1 should form a priority group for targeted advice to stop smoking.

Short-term predictors of incident stroke in older adults. The Cardiovascular Health Study

BACKGROUND AND PURPOSE

Risk factors for incident stroke have been examined in middle-aged persons, but less is known about stroke precursors in the elderly, who suffer the highest rates of stroke. Short-term risk factors for incident stroke were examined in a longitudinal, population-based study including extensive measures of subclinical disease.

METHODS

Prospective study of 5201 women and men aged 65 years and older was undertaken in the multicenter Cardiovascular Health Study.

RESULTS

During an average 3.31-year follow-up, 188 incident strokes occurred. Stroke incidence increased significantly with age and was similar in women and men. Factors associated with increased stroke risk in multivariate analysis included age, aspirin use, diabetes, impaired glucose tolerance, higher systolic blood pressure, increased time needed to walk 15 ft. frequent falls, elevated creatinine level, abnormal left ventricular (LV) wall motion and increased LV mass on echocardiography, ultrasound-defined carotid stenosis, and atrial fibrillation. Increased LV mass and carotid stenosis were associated with twofold and threefold increases in incidences of stroke, respectively (P < .001). Aspirin users had a 52% higher risk of stroke (relative risk, 1.52; 95% confidence interval, 1.1 to 2.0; P < .007) after adjustment for other factors. This association was present only among aspirin users without prior coronary disease, atrial fibrillation, claudication, or transient ischemic attack, who had an 84% higher risk (relative risk, 1.84; 95% confidence interval, 1.2 to 2.8).

CONCLUSIONS

Short-term risk of stroke has a complex relationship with aspirin use and is strongly related to subclinical disease in this sample of older adults. These relationships should be considered in assessing stroke risk in the elderly, in whom recognized and subclinical cardiovascular disease is highly prevalent.

History of parental death from stroke or heart trouble and the risk of stroke in middle-aged men

BACKGROUND AND PURPOSE

The purpose of this study was to determine the effect of a history of parental death from stroke or heart trouble on the risk of major stroke events (fatal and nonfatal) in middle-aged British men.

METHODS

A prospective study was undertaken of 7735 middle-aged men, drawn at random from general practices in 24 British towns, who were followed up for an average of 14.8 (range, 13.5 to 16.0) years.

RESULTS

In the 7683 men providing information on at least one of their parents, there were 278 major stroke events and 947 major ischemic heart disease events. A history of death from stroke or heart trouble in mother or father was associated with a significantly increased risk of stroke independent of other risk factors, including hypertension. The association is due almost entirely to an increased risk of nonfatal stroke. In comparison with men whose parents were still alive or who had no history of parental death from either heart trouble or stroke, the adjusted relative risk of stroke in men with a history of parental stroke death was 1.4 (95% confidence interval [CI], 1.1 to 2.0; P = .02), and in men with parental heart trouble death, the relative risk was 1.3 (95% CI, 1.0 to 1.7; P = .04). The positive relationships were present whether the parental death occurred before or after 70 years of age. A parental death from stroke was not associated with increased risk of an ischemic heart disease event, although the latter was significantly associated with a history of parental death from heart trouble.

CONCLUSIONS

Although factors such as hypertension and smoking are of major importance in the etiology of stroke, there is a link between a history of parental death from cardiovascular disease (stroke or heart trouble) and the risk of stroke that appears to be independent of the established risk factors.

Chromosomal mapping of quantitative trait loci contributing to stroke in a rat model of complex human disease

Stroke is a complex disorder with a poorly understood multifactorial and polygenic aetiology. We used the stroke-prone spontaneously hypertensive rat (SHRSP) as a model organism, mated it with the stroke-resistant spontaneously hypertensive rat (SHR) and performed a genome-wide screen in the resultant F2 cohort where latency until stroke, but not hypertension (a major confounder) segregated. We identified three major quantitative trait loci, STR1-3, with lod scores of 7.4, 4.7 and 3.0, respectively, that account for 28% of the overall phenotypic variance. STR2 colocalizes with the genes encoding atrial and brain natriuretic factor, peptides with important vasoactive properties. Our results demonstrate the existence of primary, blood pressure-independent genetic factors predisposing to a complex form of stroke.

Association and cosegregation of stroke with impaired endothelium-dependent vasorelaxation in stroke prone, spontaneously hypertensive rats

While hypertension is a major risk factor for stroke, it is not its sole determinant. Despite similar blood pressures, spontaneously hypertensive rats (SHR) do not share the predisposition to cerebrovascular disease typical of stroke-prone spontaneously hypertensive rats (SHRSP). We investigated vascular function in male SHR and SHRSP as well as in SHRSP/SHR-F2 hybrid animals. Animals were maintained on the appropriate dietary regimen necessary for the manifestation of stroke. Among the hybrid animals, a group of stroke-prone and a group of stroke-resistant rats were selected. Blood pressure was similar in all groups. Endothelium-independent vascular reactivity tested on isolated rings of thoracic aorta and basilar artery after death showed similar contractile and dilatory responses to serotonin and nitroglycerin, respectively, in all groups. In contrast, endothelium-dependent relaxation, in response to acetylcholine or substance P, was markedly reduced in SHRSP compared with SHR. Similarly, reduced vasodilatory responses were present in aortae of F2 rats that had suffered a stroke when compared with SHR or F2 rats resistant to stroke. The observed association and cosegregation of stroke with significant and specific impairment of endothelium-dependent vasorelaxation among SHRSP and stroke-prone F2 hybrids, respectively, suggest a potential causal role of altered endothelium-dependent vascular relaxation in the pathogenesis of stroke.

Risk factors for death from stroke in middle-aged Lithuanian men: results from a 20-year prospective study

BACKGROUND AND PURPOSE

Although in eastern Europe, mortality from stroke at present is the highest in the world, no previous prospective study of the risk factors for stroke has been reported from this part of the world. The aim of our study, therefore, was to evaluate the relations between blood pressure, serum total cholesterol, glucose intolerance, body mass index, and cigarette smoking and the risk of death from stroke in middle-aged men in Kaunas, Lithuania.

METHODS

We conducted a prospective study with an average follow-up of 17.5 years of 2295 men who had participated in risk factor surveys within the framework of the world Health Organization Kaunas-Rotterdam Intervention Study from 1972 to 1974. Risk factors included in the current analyses were smoking, blood pressure, serum total cholesterol, glucose intolerance, diabetes, and body mass index. Age-and risk factor adjusted relative risks (RR) for death of stroke were determined by use of the Cox proportional hazards model.

RESULTS

The strongest risk factors for death from stroke in middle-age men were systolic blood pressure (RR=1.02; P=.0001), diabetes (RR=4.17; P=.02), and smoking (RR=2.01; P=.004). Serum cholesterol, impaired glucose tolerance, and body mass index were not related to the risk of death from stroke. Twenty-five percent and 19% of stroke deaths were attributed to hypertension and smoking, respectively.

CONCLUSIONS

Prevention and effective control of hypertension, smoking, and diabetes are the key elements in primary prevention of stroke in eastern Europe, where stroke mortality remains high.

Variation in cardiovascular risk factors by angiographic site of lower limb atherosclerosis

OBJECTIVE

To determine differences in the levels of the cardiovascular risk factors, cigarette smoking, serum lipids and blood pressure, between three groups of patients with different sites of lower limb atherosclerosis.

DESIGN

Cross-sectional survey of a consecutive series of patients with symptoms of either intermittent claudication or rest pain.

METHODS AND MATERIALS

One hundred and ninety-two men and women who had undergone angiography were classified using the Bollinger scoring system into groups with predominantly aortoiliac, femoropopliteal or dual-site disease. History of cigarette smoking, serum cotinine, serum thiocyanate, total cholesterol and HDL cholesterol were estimated. Systolic and diastolic pressures were measured and the ankle brachial pressure index (ABPI) was calculated.

RESULTS

Eighty-five patients were classified as having femoropopliteal disease, 34 aortoiliac disease and 73 dual-site disease. After adjusting for age, sex and severity of disease, aortoiliac patients were significantly younger (p </- 0.001), more likely to be female and current smokers, and had the highest levels of diastolic blood pressure. Life time cigarette consumption (pack-years) and total cholesterol concentrations were highest in femoropopliteal disease. Patients with dual-site disease were more likely to have had a myocardial infarction and angina pectoris (p </- 0.05). Systolic blood pressure was also highest in this group.

CONCLUSION

different levels of cardiovascular risk factors may predispose individuals to atherosclerosis at different sites in the lower limb. Large population studies would be required to delineate the risks more precisely.

Family history and socioeconomic factors as predictors of myocardial infarction, unstable angina and stroke in an Italian population. PROGETTO 3A Investigators

A comprehensive case-control study was conducted in an Italian region in order to compare the influence of family history of cardiovascular events, socioeconomic factors, social networks, and their joint associations with major risk factors, on the risk, of myocardial infarction (MI), unstable angina (UA) and ischemic stroke (IS). A total of 513 patients with MI, 178 with UA, 237 with IS, and 928 hospitalised controls were recruited. The odds ratio (OR) of MI for two or more relatives with a positive history of MI was 3.6 (95% CI: 1.8-7.3). Family history of MI was predictive for UA (OR = 5.8; 95% CI: 1.2-28.7), but not for IS. A family history of stroke was more associated with the risk of MI than of IS. After adjustment for known risk factors, the OR of MI for more educated people was 2.1 (1.3-3.6) compared with less-educated people. Large family size seemed to be protective for MI. The effect of major risk factors on MI ranged from additive (diabetes) to multiplicative jointly with high education and family history of MI. A family history of stroke increased IS risk threefold jointly with smoking and hyperlipidemia, and eightfold with diabetes. Besides a family history of MI and IS, in this community a higher educational status seems to better identify groups at increased risk of MI. The joint associations have important preventive implications since by identifying high-risk individuals (for MI and IS) a more careful assessment and control of risk factors amenable to intervention may be performed.

Diabetes mellitus as a risk factor for death from stroke. Prospective study of the middle-aged Finnish population

BACKGROUND AND PURPOSE

High blood pressure is the most important risk factor for stroke. It is also known that diabetic patients are at increased risk of both hypertension and stroke. The aim of this study was to assess the independent effect of diabetes as a risk factor for stroke. Results from the previous studies of this question have been somewhat inconclusive.

METHODS

We performed a prospective study (average follow-up, 16.4 years) of 8077 men and 8572 women who had participated in risk factor surveys in Eastern Finland in 1972 (20 years of follow-up) and 1977 (15 years of follow-up). Risk factors included in the current analyses were smoking, blood pressure, antihypertensive drug treatment, serum total cholesterol, and diabetes either at baseline or developed during the follow-up. Age- and risk factor-adjusted relative risks for death of stroke were determined with the Cox proportional hazards model.

RESULTS

Diabetes mellitus was the strongest risk factor for death from stroke among both men and women in univariate and multivariate analyses. In addition, smoking and systolic blood pressure appeared to be independent risk factors among both sexes, as did serum total cholesterol among men. Men with diabetes at baseline appeared to be at a sixfold increased risk of death from stroke, while relative risk for men who developed diabetes during the follow-up was 1.7. In women, those who were diabetic at baseline were at higher risk of stroke than women who developed diabetes later (relative risks, 8.2 and 3.7, respectively). Of stroke deaths, 16% in men and 33% in women were attributed to diabetes.

CONCLUSIONS

Diabetic subjects have a very high risk of death from stroke, particularly women. Our data also suggest that the duration of diabetes is an important factor contributing to the risk of stroke.

Drugs affecting plasma fibrinogen levels. Implications for new antithrombotic strategies

Current evidence indicates that plasma fibrinogen is synthesized by the liver; that genetic and environmental factors regulate plasma fibrinogen levels; that interleukin-6 (IL-6) affects the synthesis of plasma fibrinogen by mechanisms involving protein kinase C, and that during the acute-phase response, monocytes generate a variety of monokines including IL-6. Certain drugs and nutrients have been reported to lower plasma fibrinogen levels. The mechanism(s) involved in this effect is poorly understood. However, since most of these substances quantitatively and/or qualitatively affect monocytes, the possibility that these drugs affect plasma fibrinogen levels via these cells should be considered. In addition to fibrinogen, IL-6 also regulates the synthesis of other acute-phase proteins. Especially when combined, major risk factors for atherosclerosis cause vascular injury that triggers inflammatory events. This raises the issue of whether high plasma fibrinogen levels are just the epiphenomenon of as yet unknown events in thrombosis and atherosclerosis. Thus, the issue to be addressed is whether high plasma fibrinogen concentrations should be lowered or should they serve to suggest strong interventions on established risk factors. As for other risk factors, fibrinogen measurements in population-based studies, in parallel with measurements of established risk factors will help define appropriate directions to be followed to gain insight into the issue and define new antithrombotic strategies.

Respiratory function and risk of stroke

BACKGROUND AND PURPOSE

This report examines the relationship between lung function and risk of major stroke events (fatal and nonfatal).

METHODS

We completed a prospective study of 7735 men aged 40 to 59 years at screening selected at random from one general practice in each of 24 British towns.

RESULTS

During the mean follow-up period of 14.8 years, there were 277 major stroke events in the 7650 men with data on forced expiratory volume in 1 second (FEV1). After exclusion of 499 men with definite myocardial infarction, stroke, or atrial fibrillation at screening, 7151 men experienced 239 major stroke events. Lower levels of FEV1 were associated with a significant increase in risk of stroke even after adjustment for age, smoking, social class, physical activity, alcohol intake, systolic blood pressure, antihypertensive treatment, diabetes, and preexisting ischemic heart disease. Relative risk in the low third (< 3.10 L) versus high third (> 3.65 L) was 1.4 (95% confidence interval, 1.0 to 2.0). The inverse association between FEV1 and stroke was only apparent in older men, current nonsmokers, hypertensive men, and men with preexisting ischemic heart disease. Lower FEV1 was associated with higher rates of stroke in hypertensive men irrespective of smoking status. Inclusion of FEV1 in a risk score for stroke provided only a small increase in the absolute risk or the yield of cases in the top fifth of the score distribution during the follow-up period.

CONCLUSIONS

Lower levels of FEV1 are associated with an increased risk of stroke in those already at high risk, eg, those with ischemic heart disease or hypertension. However, the association is not strong enough to warrant the use of FEV1 in making clinical decisions regarding the treatment of hypertension as it relates to the prevention of stroke.

Prevalence of fatty liver in Japanese children and relationship to obesity. An epidemiological ultrasonographic survey

The prevalence of fatty liver in children is unknown and its relationship to obesity is poorly defined. The present study of 810 northern Japanese children (4-12 years old) determined the prevalence of fatty liver in the pediatric population and its relationship to obesity. Diagnosis of fatty liver was based on established real-time ultrasonographic criteria. The overall prevalence of fatty liver was 2.6% and was higher for boys (3.4%) than for girls (1.8%), although not statistically significant (P = 0.15). Fatty liver was found in children as young as 6 years of age. There was no significant association between the prevalence of fatty liver and height (physical growth). There was a strong positive correlation between fatty liver prevalence and established obesity indices: Rohrer's Index--chi 2 linear trend = 59.2, P < 0.0001; body mass index--chi 2 linear trend = 91.6, P < 0.0001; and age-gender-adjusted Japanese standard index of weight for height--chi 2 linear trend = 93.2, P < 0.0001. However, direct measurement of abdominal subcutaneous fat thickness by ultrasonography was the best predictor of fatty liver: chi 2 linear trend = 159, P < 0.0001. These results indicate that fatty liver may develop very early in life, and there is a direct relationship between degree of obesity and fatty liver in children.

Relationships of generalized and regional adiposity to insulin sensitivity in men

The relative impacts of regional and generalized adiposity on insulin sensitivity have not been fully defined. Therefore, we investigated the relationship of insulin sensitivity (measured using hyperinsulinemic, euglycemic clamp technique with [3-3H]glucose turnover) to total body adiposity (determined by hydrodensitometry) and regional adiposity. The latter was assessed by determining subcutaneous abdominal, intraperitoneal, and retroperitoneal fat masses (using magnetic resonance imaging) and the sum of truncal and peripheral skinfold thicknesses. 39 healthy middle-aged men with a wide range of adiposity were studied. Overall, the intraperitoneal and retroperitoneal fat constituted only 11 and 7% of the total body fat. Glucose disposal rate (Rd) and residual hepatic glucose output (rHGO) values during the 40 mU/m2.min insulin infusion correlated significantly with total body fat (r = -0.61 and 0.50, respectively), subcutaneous abdominal fat (r = -0.62 and 0.50, respectively), sum of truncal skinfold thickness (r = -0.72 and 0.57, respectively), and intraperitoneal fat (r = -0.51 and 0.44, respectively) but not to retroperitoneal fat. After adjusting for total body fat, the Rd and rHGO values showed the highest correlation with the sum of truncal skinfold thickness (partial r = -0.40 and 0.33, respectively). We conclude that subcutaneous truncal fat plays a major role in obesity-related insulin resistance in men, whereas intraperitoneal fat and retroperitoneal fat have a lesser role.

Vitamin C and risk of death from stroke and coronary heart disease in cohort of elderly people

OBJECTIVES

To determine whether vitamin C status, as measured by dietary intake and plasma ascorbic acid concentration, is related to mortality from stroke and coronary heart disease in people aged 65 and over.

DESIGN

A 20 year follow up study of a cohort of randomly selected elderly people living in the community who had taken part in the 1973-4 Department of Health and Social Security nutritional survey and for whom dietary and other data had been recorded.

SETTING

Eight areas in Britain (five in England, two in Scotland, and one in Wales).

SUBJECTS

730 men and women who had completed a seven day dietary record and who had no history or symptoms of stroke, cerebral arteriosclerosis, or coronary heart disease when examined by a geriatrician in 1973-4.

RESULTS

Mortality from stroke was highest in those with the lowest vitamin C status. Those in the highest third of the distribution of vitamin C intake had a relative risk of 0.5 (95% confidence interval 0.3 to 0.8) compared with those in the lowest third, after adjustment for age, sex, and established cardiovascular risk factors. The relation between vitamin C intake and stroke was independent of social class and other dietary variables. A similar gradient in risk was present for plasma ascorbic acid concentrations. No association was found between vitamin C status and risk of death from coronary heart disease.

CONCLUSION

In elderly people vitamin C concentration, whether measured by dietary intake or plasma concentration of ascorbic acid, is strongly related to subsequent risk of death from stroke but not from coronary heart disease.

Body fat and stroke: unmasking the hazards of overweight and obesity

STUDY OBJECTIVE

It has been frequently noted that overweight and obesity have a stronger relationship to hypertension and diabetes mellitus than to the risk of stroke. The reason for this observation has not been clear. This study aimed to examine the lifelong relation between body fat and stroke to shed light on why the public health risks of overweight and obesity have tended to be obscured in previous epidemiological studies.

DESIGN

Case-control study.

SETTING

Eleven general practices in west Birmingham.

PARTICIPANTS

Altogether 125 men and women who had just had their first stroke and were aged 35-74 years and 198 controls frequency matched for age and sex were recruited over 24 months during 1988-90.

MAIN RESULTS

Those in both the thinnest and fattest quartiles of subscapular skinfold thickness were at increased risk of stroke compared with those in the middle quartiles (age adjusted odds ratios 2.12 (95% confidence interval (CI) 1.2, 3.9) and 2.08 (1.1, 3.8) respectively). When lifelong maximum reported body mass index was assessed the hazards of obesity but not leanness were seen (odds ratio for the highest versus the lowest quartile were--age adjusted, 1.54 (0.8, 3.0) and multiple risk factor adjusted, 2.25 (1.1, 4.5). This lifelong pattern of risk seemed to be established early, the odds ratios for the highest versus the lowest quartile of reported body mass index aged 21 years were--age adjusted, 2.18 (1.1, 4.4) and multiple risk factor adjusted 2.13 (1.1, 4.2). The risks of both maximum reported body mass index and reported body mass index aged 21 years were more clear in those who had never smoked cigarettes (test for trend in odds ratio, p = 0.009 and p = 0.02 respectively).

CONCLUSIONS

Potentially important risks of excessive body fat for stroke can be obscured by both a history of cigarette smoking and thinness associated with deteriorating health. The results seem to explain why excess body fat has previously been consistently related to hypertension and diabetes mellitus but less consistently to stroke. Avoiding overweight and obesity during adult life offers protection against stroke.

Effects of different antihypertensive drugs on plasma fibrinogen in hypertensive patients

1. In order to evaluate whether treatment with different antihypertensive drugs would affect plasma fibrinogen levels, 118 mild to moderate essential hypertensive subjects, all males, aged 18 to 65 years, were randomly treated with amlodipine 10 mg, atenolol 100 mg, hydrochlorothiazide 25 mg or lisinopril 20 mg, all given once daily for 8 weeks. 2. Before and after 8 weeks' treatment, blood pressure (BP), heart rate (HR), fibrinogen, total cholesterol (TC), HDL-C, LDL-C, triglycerides (TG), plasma glucose, plasma uric acid, serum creatinine and serum potassium were evaluated. 3. All four medications significantly reduced BP values, although the BP lowering effect of lisinopril, amlodipine and atenolol was significantly greater compared with that of hydrochlorothiazide. 4. Plasma fibrinogen levels were unaffected by atenolol, hydrochlorothiazide and amlodipine, whereas they were significantly decreased by lisinopril (-11.2%, P = 0.002). This fibrinogen lowering effect was more evident in smokers (-17.7%) than in non smokers (-7.4%). 5. Atenolol and amlodipine did not significantly affect plasma lipids, hydrochlorothiazide increased TC, LDL-C and TG and reduced HDL-C; lisinopril increased HDL-C and decreased TC and LDL-C. 6. Hydrochlorothiazide increased plasma glucose and uric acid concentrations, which were unaffected by the other drugs. The diuretic also reduced serum potassium. 7. The results of this study indicate that lisinopril reduces levels of plasma fibrinogen and confirm that different antihypertensive drugs may elicit different metabolic effects, which may variously influence the overall risk profile of the hypertensive patients.

Prevalence of stroke at high altitude (3380 m) in Cuzco, a town of Peru. A population-based study

BACKGROUND AND PURPOSE

We carried out a door-to-door survey on stroke prevalence at high altitude in Cuzco City, a town in the Peruvian Andes located 3380 m above sea level.

METHODS AND RESULTS

Among the 3246 screened individuals over 15 years old, there were 21 cases of first-ever completed stroke, yielding a crude prevalence ratio of 6.47 per 1000 (95% confidence interval [CI], 3.71 to 8.93 per 1000). The age-adjusted to WHO population point prevalence ratio was 5.74 per 1000 (95% CI, 3.14 to 8.35 per 1000), and the age-adjusted to North American US population point prevalence ratio was 8.58 per 1000 (95% CI, 5.44 to 11.75 per 1000). Multivariate logistic regression analysis suggested that age, polycythemia, high consumption of alcohol, and area of residence were associated with stroke prevalence. Our results suggest that the stroke prevalence in the central areas of Cuzco with sedentary people having a relatively high standard of living was higher than that in the peripheral areas with people with a relatively lower standard of living and less sedentary activities (odds ratio, 5.8; 95% CI, 1.4 to 23).

CONCLUSIONS

The prevalence of stroke suggests that stroke may be a public health problem in developing countries. This study suggests the importance of environmental factors such as altitude and lifestyle in stroke occurrence. The role of these factors should be confirmed and taken into account in future stroke prevalence studies.

Recent infection as a risk factor for cerebrovascular ischemia

BACKGROUND AND PURPOSE

Previous infection is discussed as a risk factor for ischemic stroke in children and younger adults. We tested the hypothesis that the role of recent infection in cerebrovascular ischemia is not restricted to younger patients and investigated which infections are mainly relevant in this respect.

METHODS

We performed a case-control study with 197 patients aged 18 to 80 years with acute cerebrovascular ischemia and 197 randomly selected control subjects matched for sex, age, and area of residence.

RESULTS

Infection within 1 week before ictus or examination was significantly more common among patients (38 of 197) than control subjects (10 of 197; odds ratio [OR], 4.5; 95% confidence interval [CI], 2.1 to 9.7). Patients more often had febrile and subfebrile infections (> or = 37.5 degrees C) than control subjects (29 of 197 versus 5 of 197; OR, 7.0; 95% CI, 2.5 to 20). Respiratory tract infections were most common in both groups. Bacterial infections dominated among patients but not among control subjects. Infection increased the risk for cerebrovascular ischemia in all age groups; this reached significance for patients aged 51 to 60 and 61 to 70 years. The profile of vascular risk factors was similar in patients with and patients without previous infection. Infection remained a significant risk factor when previous stroke, hypertension, diabetes mellitus, coronary heart disease, and current smoking were included as covariates in a logistic model (OR, 4.6; 95% CI, 1.9 to 11.3).

CONCLUSIONS

Recent infection, primarily of bacterial origin, may be a risk factor for cerebrovascular ischemia in older as well as younger patients.

Heterogeneity in adipose tissue metabolism: causes, implications and management of regional adiposity

The observation that different patterns of adipose tissue distribution are associated with different metabolic abnormalities, has recently given new impetus to research in obesity. Due to several methodologic problems, however, many aspects of regional excess of adipose tissue are still poorly understood. Among them, the causes and the metabolic consequences of regional adiposity are particularly important. Heterogeneity in adipose tissue distribution may be determined by a combination of genetic and hormonal causes. Both factors may determine differences in metabolism of various adipose tissue compartments primarily by regulating LPL production, storage and release of triacylglycerols, and aromatization of androgens. Furthermore, changes in adipocyte sensitivity to hormones such as, sex steroids, glucocorticoids, insulin and adrenergic hormones may also regulate fat distribution in various adipose tissue compartments. The metabolic heterogeneity of adipose tissue from various compartments, particularly the differences between the "portal" and subcutaneous adipose tissues, may account for several metabolic abnormalities associated with "upper body adiposity". However, no direct evidence is available to confirm this hypothesis. Recent advances in the methodology to study adipose tissue distribution (mainly CT and MRI) may provide the necessary tools to evaluate the true impact of adiposity in various compartments on intermediary metabolism and to identify a "morbid" adipose tissue compartment. These observations may help in designing better therapeutic strategies targeted towards regional adiposity and its metabolic complications.

Body mass index and thromboembolic stroke in nonsmoking men in older middle age. The Honolulu Heart Program

BACKGROUND AND PURPOSE

While evidence suggests that obesity has an independent relation to coronary artery disease, similar findings for stroke have not been established. The purpose of this study was to examine the relation between body mass index and the risk of thromboembolic stroke independently of other risk factors.

METHODS

Since 1965, the Honolulu Heart Program has followed a cohort of men in a prospective study of cardiovascular disease. This article examines the relationship between the baseline measurement of body mass index and the risk of thromboembolic stroke in 1163 nonsmoking men in older middle age (55 to 68 years). Men who had an elevated risk of stroke due to hypertension, diabetes, and other risk factors were excluded from the analysis.

RESULTS

After 22 years of follow-up, the rate of stroke increased significantly with increasing levels of body mass (P < .01). In the bottom tertile of the body mass index, the rate of thromboembolic stroke was 28.7 per 1000 (11/383). In the middle tertile, the rate was increased by 40% to 40.7 per 1000 (16/393), and in the top tertile, the rate of thromboembolic stroke was 55.4 per 1000 (21/387), a twofold excess compared with the bottom tertile. After adjustment for age and the residual effects of confounding risk factors, including systolic blood pressure and serum glucose, the estimated relative risk of stroke for the average body mass index in the top tertile (26.6 kg/m2) compared with that in the bottom tertile (20.3 kg/m2) was 2.1 (95% confidence interval, 1.1 to 4.1). These findings were not affected by coronary events that occurred in the course of follow-up, nor did they appear to be influenced by deaths from other causes.

CONCLUSIONS

We conclude that elevated body mass is associated with an increased risk of thromboembolic stroke in nonsmoking men in older middle age who are free of commonly observed conditions related to cardiovascular disease.

The efficacy of multiple risk factor intervention in treated hypertensive men during long-term follow up. Risk Factor Intervention Study Group

OBJECTIVE

To examine the feasibility and efficacy of a multifactorial intervention programme directed towards hypercholesterolaemia, smoking, and diabetes mellitus in treated hypertensive patients after more than 3 years' follow-up and to describe the incidence of cardiovascular complications.

DESIGN

Open, randomized, parallel-group study with allocation either to a comprehensive multiple risk factor modification programme or to usual care.

SETTING

Outpatient clinic in a city hospital.

PATIENTS

A total of 508 male patients with treated hypertension, aged 50-72 years, with at least one of the following: serum cholesterol > or = 6.5 mmol L-1, smoking or diabetes mellitus.

INTERVENTION

Individually given advice and group meetings based on nutritional advice and behavioral treatment principles. Drug therapy could be instituted to achieve the treatment goals in the intervention group: serum total cholesterol below 6.0 mmol L-1, no smoking, and HbA1c below 6.0%. Diastolic blood pressure below 90 mmHg was the treatment goal in both groups.

MAIN OUTCOME MEASUREMENTS

Serum cholesterol, HbA1c, diastolic blood pressure, smoking. Cardiovascular end-points were recorded.

RESULTS

The net changes were (change intervention--change usual care): serum cholesterol -5.0% (95% confidence interval, -7.6 to -2.3%), 17.6% more stopped smoking (P = 0.04); diastolic blood pressure and HbA1c remained unchanged. The incidence of stroke was lower in the intervention group compared with the usual-care group: 2.0 and 6.7%, respectively (P = 0.017).

CONCLUSION

The intervention programme was comparatively successful with regards to the effects on hypercholesterolaemia and smoking habits. An unexpected decrease in the stroke incidence was observed in the intervention group compared with the usual-care group.

The importance of family history in cerebrovascular disease

BACKGROUND AND PURPOSE

The role of genetics in cerebrovascular disease remains controversial. The purpose of this study was to assess the influence of family history on atherothrombotic infarction or transient ischemic attack.

METHODS

Ninety patients with stroke or transient ischemic attack and 90 age- and sex-matched community control subjects were studied prospectively. Medical and family histories were obtained from all subjects, and a complete physical examination was performed.

RESULTS

Eighty-five patients and 86 control subjects knew their family history for ischemic heart disease and stroke. A positive history for ischemic heart disease was present in 62 (73%) of the patients and 46 (53%) of the control subjects (P = .019), and a positive family history for stroke was present in 38 (47%) of the patients and 21 (24%) of the control subjects (P = .014).

CONCLUSIONS

Although a positive vascular family history was not an independent risk factor in a multivariate analysis, it was an excellent marker of the presence of other established vascular risk factors. Personal histories of ischemic heart disease, hypertension, and hyperlipidemia were found to be significant independent risk factors for stroke.

Influence of total cholesterol, high density lipoprotein cholesterol, and triglycerides on risk of cerebrovascular disease: the Copenhagen City Heart Study

OBJECTIVE

To estimate the influence of plasma total cholesterol, high density lipoprotein cholesterol, and triglycerides on risk of cerebrovascular disease.

DESIGN

The Copenhagen City Heart Study is a prospective observational survey with two cardiovascular examinations at five year intervals. Non-fasting plasma lipids were measured in participants once at each examination, along with other variables. The Cox regression model was used to establish the effect of the factors recorded on cerebrovascular events of mostly, but not exclusively, ischaemic origin.

SUBJECTS

19,698 women and men at least 20 years old, randomly selected after age stratification from an area of central Copenhagen.

MAIN OUTCOME MEASURES

Initial cases of stroke and transient ischaemic attack recorded from hospital records and death certificates from 1976 through 1988.

RESULTS

660 non-haemorrhagic and 33 haemorrhagic events were recorded. Total cholesterol was positively associated with risk of non-haemorrhagic events, but only for levels > 8 mmol/l, corresponding to the upper 5% of the distribution in the study population. For lower plasma cholesterol values the relative risk remained nearly constant. Plasma triglyceride concentration was significantly, positively associated with risk of non-haemorrhagic events. The relative risk corresponding to an increase of 1 mmol/l was 1.12 (95% confidence interval 1.07 to 1.16). There was a negative, log linear association between high density lipoprotein cholesterol and risk of non-haemorrhagic events (0.53 (0.34 to 0.83)). There was no indication that the effects of plasma lipids were different in women and men.

CONCLUSIONS

The pattern of the association between plasma cholesterol and risk of ischaemic cerebrovascular disease was not log linear, and the increased risk was confined to the upper 5% of the cholesterol distribution. Further studies should concentrate on the association between plasma cholesterol and verified haemorrhagic stroke.

Carotid plaque, aging, and risk factors. A study of 457 subjects

BACKGROUND AND PURPOSE

The aim of this study was to assess the prevalence of extracranial carotid artery atherosclerosis and its relation to principal cardiovascular risk factors at different ages in a sample of the general population.

METHODS

B-mode ultrasonography was used to investigate the carotid district in 457 subjects (231 men and 226 women; mean age, 55.4 +/- 18.7 years; range, 18 to 97 years) in the metropolitan area. The ultrasonographic findings were then related to risk factors.

RESULTS

Carotid plaques were found in 178 subjects (38.9%). The prevalence of atherosclerosis, number of plaques, and severity of stenosis were observed to increase with age. Age (P < .0001), cigarette smoking (P < .0001), male sex (P < .001), total cholesterol (P < .05), and, inversely, the ratio of high-density lipoprotein cholesterol to total cholesterol (P < .05) were found to be independently associated with carotid atherosclerosis. Stratified analysis by sex and age showed effect modifications by age on cigarette smoking, total cholesterol, and the ratio of high-density lipoprotein cholesterol to total cholesterol. After multivariate analysis including interaction terms, cigarette smoking and cholesterol levels were not longer found to be associated with carotid atherosclerosis in elderly subjects. Age (P < .01), total cholesterol (P < .05), and diabetes (P < .05) were positively related to the severity of vascular narrowing.

CONCLUSIONS

There is a high prevalence of asymptomatic carotid atherosclerosis in the general population, particularly among the very old. The association between risk factors and carotid atherosclerosis is less pronounced in the elderly than in younger subjects.