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

Predictive value of fibrinogen levels for 90-day functional outcomes after intravenous thrombolysis in patients with acute ischaemic stroke

PURPOSE

We aimed to investigate the correlation between fibrinogen levels and functional outcomes at 90 days after intravenous thrombolysis therapy (IVT) in patients with acute ischaemic stroke (AIS).

METHODS

We identified patients with AIS who received IVT (alteplase 0.6 or 0.9 mg/kg) between 1 January 2019 and 31 March 2022 in Yancheng 1st People's Hospital. Fibrinogen levels were measured before IVT, and the 90-day post-stroke functional outcome was evaluated using the modified Rankin Scale (mRS). An mRS score of 0-2 indicated functional independence, whereas an mRS score of 3-6 indicated functional dependence. Potential outcome predictors were evaluated using univariate and multivariate analyses, and receiver operating characteristic (ROC) curve analysis was performed to assess the performance of fibrinogen levels in predicting the 90-day outcome.

RESULTS

A total of 276 patients with AIS who received IVT within 4.5 h of stroke onset were enrolled, of whom 165 and 111 were categorised into the functional independence and functional dependence groups, respectively. Univariate analysis showed that the fibrinogen, homocysteine, high-density lipoprotein cholesterol, and D-dimer levels; age; National Institutes of Health Stroke Scale (NIHSS) score on admission; NIHSS score 24 h after IVT; and incidence of cardioembolism were higher in the functional dependence group than in the functional independence group (P < 0.05). Meanwhile, the thrombin time and the incidence of small-vessel occlusion in the functional dependence group were smaller than those in the functional independence group (P < 0.05). Multivariate logistic regression analysis showed that fibrinogen and homocysteine levels were both independent risk factors for 90-day functional dependence in patients with AIS (odds ratio [OR] 2.822, 95% confidence interval [95% CI]: 1.214-6.558, P = 0.016 for fibrinogen; OR 1.048, 95 %CI: 1.002-1.096, P = 0.041 for homocysteine). The area under the ROC curve of fibrinogen levels before IVT for predicting poor functional outcomes was 0.664, with a sensitivity, specificity, positive predictive value, and negative predictive value of 40.9%, 80.8%, 68.9%, and 64.3%, respectively.

CONCLUSION

In patients with AIS, fibrinogen levels have a certain predictive value for short-term functional outcomes after IVT.

Family History is Related to High Risk of Recurrent Events after Ischemic Stroke or Transient Ischemic Attack

OBJECTIVE

Prior data suggest paternal or sibling stroke was associated with increased risk of offspring stroke. Whether family history of cardiovascular disease (FHc) predicts risk of stroke recurrence remains unclear, we aim to determine this issue on patients with ischemic stroke (IS) or transient ischemic attack (TIA).

MATERIALS AND METHODS

This is a post hoc analysis based on the Third China National Stroke Registry III. IS/TIA patients with data of FHc status were included. FHc was defined as family history of coronary heart disease (CHD) or stroke among first-degree relatives (include parents, children, and siblings (same parents)). Cox proportional hazards regression models were performed to assess the association between FHc and recurrent events at 1 year follow-up.

RESULTS

Totally 14,208 patients with verified FHc status were included, 4,454 (31.3%) were female and the median (IQR) age was 62.0 (54.0, 70.0) years. Of these, 294 (2.1%), 726 (5.1%) and 1936 (13.6%) had family history of both CHD and stroke, family history of CHD, and family history of stroke only, respectively. Using multivariable Cox models adjusted for age, sex, and vascular risk factors, we found that patients with FHc experienced higher risk of stroke recurrence (HR=1.151, 95%CI=1.000-1.324) and combined vascular events (HR=1.186, 95%CI=1.036-1.358) at 1 year compared with those without FHc. In sensitivity analysis on patients who received primary secondary prevention treatment of antiplatelet and statins, the association persisted.

CONCLUSIONS

FHc is associated with increased risk of stroke recurrence even under primary secondary prevention treatment.

The impact of time-updated resting heart rate on cause-specific mortality in a random middle-aged male population: a lifetime follow-up

Background

A high resting heart rate (RHR) is associated with an increase in adverse events. However, the long-term prognostic value in a general population is unclear. We aimed to investigate the impact of RHR, based on both baseline and time-updated values, on mortality in a middle-aged male cohort.

Methods

A random population sample of 852 men, all born in 1913, was followed from age 50 until age 98, with repeated examinations including RHR over a period of 48 years. The impact of baseline and time-updated RHR on cause-specific mortality was assessed using Cox proportional hazard models and cubic spline models.

Results

A baseline RHR of ≥ 90 beats per minute (bpm) was associated with higher all-cause mortality, as compared with an RHR of 60–70 bpm (hazard ratio [HR] 1.60, 95% confidence interval [CI] 1.17–2.19, P = 0.003), but not with cardiovascular (CV) mortality. A time-updated RHR of < 60 bpm (HR 1.41, 95% CI 1.07–1.85, P = 0.014) and a time-updated RHR of 70–80 bpm (HR 1.34, 95% CI 1.02–1.75, P = 0.036) were both associated with higher CV mortality as compared with an RHR of 60–70 bpm after multivariable adjustment. Analyses using cubic spline models confirmed that the association of time-updated RHR with all-cause and CV mortality complied with a U-shaped curve with 60 bpm as a reference.

Conclusion

In this middle-aged male cohort, a time-updated RHR of 60–70 bpm was associated with the lowest CV mortality, suggesting that a time-updated RHR could be a useful long-term prognostic index in the general population.

Graphic abstract

Determinants of Stroke in a General Male Population

Background and Purpose—

To further improve preventive strategies against stroke, there is a need for epidemiological long-term studies. The study aimed at a prospective investigation of stroke determinants in the general male population.

Methods—

During a period of 48 years, from 50 to 98 years of age, a population-based sample of 854 men was followed using repeated medical examinations, lifestyle questionnaires, data from hospital records and the National Cause of Death Register.

Results—

Determinants of ischemic stroke were atrial fibrillation (hazard ratio [HR], 6.61; 95% CI, 4.47–9.77); mother dead from cardiovascular disease (HR, 1.53; 1.09–2.17); high education (HR, 0.81; 0.69–0.96); and high physical activity level during leisure time (HR, 0.68; 0.50–0.93). For hemorrhagic stroke heart rate (HR, 1.04; 1.01–1.06) and mother dead from stroke (HR, 3.56; 1.43–8.87) constituted an increased risk. Statistically significant determinants for all stroke were atrial fibrillation (HR, 5.34; 3.68–7.75); high diastolic blood pressure (HR, 1.02; 1.01–1.03); high body weight (HR, 0.96; 0.94–0.99); high educational level (HR, 0.79; 0.68–0.92); wide waist circumference (HR, 1.04; 1.01–1.07); smoking (HR, 1.25; 1.06–1.48); mother dead from cerebrovascular disease (HR, 1.43; 1.05–1.94); and diabetes mellitus (HR, 1.65; 1.02–2.68). Of all men diagnosed with atrial fibrillation, 88% had a stroke during follow-up.

Conclusions—

Atrial fibrillation was by far the strongest determinant of stroke during 48 years of follow-up in a male population sample followed until the age of 98 years. The results warrant improved prophylaxis through intense treatment of modifiable determinants.

Body fat distribution and risk of incident ischemic stroke in men and women aged 50 to 74 years from the general population. The KORA Augsburg cohort study

Background

It remains controversial whether measures of general or abdominal adiposity are better risk predictors for ischemic stroke. Furthermore, so far it is unclear whether body fat mass index (BFMI) and fat free mass index (FFMI) are risk predictors for ischemic stroke. This study examined the sex-specific relevance of body mass index (BMI), BROCA Index, waist circumference (WC), waist-height ratio (WHtR), BFMI and FFMI for the development of ischemic stroke in a Caucasian population.

Material and methods

The prospective population-based cohort study was based on 1917 men and 1832 women (aged 50 to 74 years) who participated in the third (1994/95) or fourth (1999/2001) MONICA/KORA Augsburg survey. Subjects were free of stroke at baseline. Standardized anthropometric and bioelectric impedance measurements were obtained at baseline. Hazard ratios (HR) were estimated from Cox proportional hazard models.

Results

During a median follow-up of 9.3 years 128 ischemic strokes occurred in men and 81 in women, respectively. Coded as quartiles WC and WHtR were significantly associated with incident stroke in multivariable analyses in women (comparing the 4^th vs. the bottom quartile), but none of the adiposity measures was significantly associated with incident stroke in multivariable adjusted analyses in men. When anthropometric measures were used as continuous variables, these findings were confirmed. After multivariable adjustment the associations between obesity measures and incident ischemic stroke were statistically significant only for WC (HR 1.39, 95%CI 1.12-1.72) and WHtR in women (HR 1.39, 95%CI 1.12-1.73) per increase of 1 standard deviation. In both sexes the measures BFMI and FFMI were no independent predictors for incident ischemic stroke.

Conclusions

Abdominal obesity measures are independent predictors of incident ischemic stroke in women but not in men from the general adult population. Thus, it may be of particular importance for women to prevent central obesity in order to reduce their risk of ischemic stroke.

Relation of Risk of Stroke in Patients With Atrial Fibrillation to Body Mass Index (from Patients Treated With Rivaroxaban and Warfarin in the Rivaroxaban Once Daily Oral Direct Factor Xa Inhibition Compared with Vitamin K Antagonism for Prevention of Stroke and Embolism Trial in Atrial Fibrillation Trial)

We investigated stroke outcomes in normal weight (body mass index [BMI] 18.50 to 24.99 kg/m²), overweight (BMI 25.00 to 29.99 kg/m²), and obese (BMI ≥30 kg/m²) patients with atrial fibrillation treated with rivaroxaban and warfarin. We compared the incidence of stroke and systemic embolic events as well as bleeding events in normal weight (n = 3,289), overweight (n = 5,535), and obese (n = 5,206) patients in a post hoc analysis of the Rivaroxaban Once Daily Oral Direct Factor Xa Inhibition Compared with Vitamin K Antagonism for Prevention of Stroke and Embolism Trial in Atrial Fibrillation trial. Stroke and systemic embolic event rates per 100 patient-years were 2.93 in the normal weight group (reference group), 2.28 in the overweight group (adjusted hazard ratio [HR] 0.81, 95% CI 0.66 to 0.99, p = 0.04) and 1.88 in the obese group (adjusted HR 0.69, 95% CI 0.55 to 0.86, p <0.001). The risk of stroke was statistically significantly lower for obese patients with BMI ≥35 than that for normal weight patients in both the rivaroxaban and warfarin groups (rivaroxaban: HR 0.62, 95% CI 0.40 to 0.96, p = 0.033; warfarin: HR 0.48, 95% CI 0.31 to 0.74, p <0.001). In conclusion, in patients with atrial fibrillation treated with anticoagulant therapy, increased BMI was associated with decreased stroke risk. Warfarin and the novel anticoagulant rivaroxaban are effective in stroke prevention in all subgroups of obese patients.

Echocardiographic characteristics of hypertensive patients affected by transient ischemic attack: a cross-sectional study

Atrial septal aneurysm (ASA), common finding in normal echocardiographies, has been described in association with transient ischemic attacks (TIAs)/strokes, as well as hypertensive end-organ damage such as left ventricular (LV) hypertrophy. Aim of this study was to assess if a cluster of echocardiographic aspects could characterize TIA hypertensive patients. A cross-sectional study on patients with history of TIA, referring to a Hypertension Center echolab, has been performed. A total of 5223 patients received transthoracic echocardiography. TIA patients were 292 (5.6%). A total of 102 age/sex-matched patients without TIA have been collected as controls. The main characteristic of TIA patients resulted ASA/bulging (B) (TIA 61%, controls 6%, P = .0001). Other aspect was LV concentric remodeling (TIA 32.3%, controls 20.8%, P = .029) and mitral flow aspects of diastolic dysfunction. After adjustment for age and hypertension, ASA/B (odds ratio [OR] = 62.4, 95% confidence interval [CI]: 13.6-73.9, P < .001), followed by LV concentric hypertrophy (OR = 2.1, 95% CI: 1.1-4.3, P = .043), was associated with a positive TIA history. A binary logistic regression performed in ASA/B patients, identified relative wall thickness as the strongest TIA-associated aspect (OR = 53.4, 95% CI: 11.9-74.18, P = .001). ASA/B, common finds in general population, could carry a significant incremental possibility of association with TIA when concentric geometry, frequent hypertensive aspect, is present as well.

Association of general and abdominal obesity with age, endocrine and metabolic factors in Asian men

OBJECTIVE

This study made use of the percent abdominal fat to define abdominal obesity (AbO) and examined the differential associations of general obesity (GOb) and AbO with age, metabolic and endocrine factors.

METHODS

Metabolic, endocrine and anthropometric factors and body composition were measured in 481 Asian men.

RESULTS

A DEXA-derived ≥25% abdominal fat (PAbdF) was used to define men with AbO. Age was directly associated with PAbdF and percent total body fat (PBF). Exercise intensity was negatively associated with PBF. Both PBF and PAbdF were associated with HDL and LDL, but have opposite correlation with triglyceride. Furthermore, both PBF and PAbdF were associated with the number of metabolic syndrome (MetS) risk factors. Men with GOb had lower levels of percent lean mass (PLM), testosterone and bioavailable testosterone, and higher insulin and glucose levels. Men with AbO had lower arm and leg fat, higher insulin levels and triglycerides.

CONCLUSIONS

Men with GOb and AbO had different pattern of body composition. Age may be a contributory factor in AbO and a sedentary lifestyle may contribute to GOb. Both GOb and AbO are associated with an increased risk of MetS, with GOb more predispose to risk of diabetes, while AbO more at risk for cardiovascular diseases.

Left ventricular relative wall thickness versus left ventricular mass index in non-cardioembolic stroke patients

In non-cardioembolic stroke patients, the cardiac manifestations of high blood pressure are of particular interest. Emerging data suggest that echocardiographically determined left ventricular hypertrophy is independently associated with risk of ischemic stroke.The primary objective of this study was to evaluate the frequency of different patterns of left ventricular (LV) remodeling and hypertrophy in a group of consecutive patients admitted with non-cardioembolic stroke or transient ischemic attack (TIA). In particular, we were interested in how often the relative wall thickness (RWT) was abnormal in patients with normal LV mass index (LVMI). As both abnormal RWT and LVMI indicate altered LV remodeling, the secondary objective of this research was to study whether a significant number of patients would be missing the diagnosis of LV remodeling if the RWT is not measured.All patients were referred within 48 hours after a stroke or a TIA for a clinically indicated transthoracic echocardiogram. The echocardiographic findings of consecutive patients with non-cardioembolic stroke or TIA were analyzed.All necessary measurements were performed in 368 patients, who were enrolled in the study. Mean age was 63.7 ± 12.5 years, 64.4% men. Concentric remodeling carried the highest frequency, 49.2%, followed by concentric hypertrophy, 30.7%, normal pattern, 15.5%, and eccentric hypertrophy, 4.1%. The frequency of abnormal left ventricular RWT (80.4%) was significantly higher than that of abnormal LVMI (35.3%), (McNemar P < 0.05).In this group of non-cardioembolic stroke patients, abnormal LV remodeling as assessed by relative wall thickness is very frequent. As RWT was often found without increased LV mass, the abnormal left ventricular geometry may be missed if RWT is not measured or reported.

Risk Factors Assessed in Adolescence and the Later Risk of Stroke in Men: A 33-Year Follow-Up Study

Background: Stroke is a common cause of death, and a leading contributor to long-term disability. The cost associated with the disease is great. Several modifiable risk factors for stroke have been found in older cohorts; however, no study to date has investigated the effects of these risk factors from late adolescence. Methods: The study cohort comprised 811,579 Swedish men (mean age, 18 years) that participated in the mandatory military conscription service in Sweden between 1969 and 1986. Some risk factors for stroke, such as body mass index, systolic and diastolic blood pressure, and cognitive function, were assessed at conscription. Aerobic fitness was also assessed at conscription, using a braked ergometer cycle test. Other risk factors for stroke, including stroke in subjects' parents, and socioeconomic factors including highest achieved level of education and annual income 15 years after conscription, were collected through national register linkage using the personal identification number. Stroke diagnosis among the study participants was tracked in the National Hospital Discharge Patient Register. Results: During a median follow-up period of 33 years 6,180 ischemic strokes and 2,104 hemorrhagic strokes were diagnosed in the cohort at a mean age of 47.9 years. Strong independent risk factors (all p <1.0 × 10−6) for ischemic stroke included low aerobic fitness (hazard ratio [HR], 0.84 per standard deviation [SD] increase), high BMI (HR, 1.15 per SD increase), diabetes (HR, 2.85), alcohol intoxication (HR, 1.93), low annual income (HR, 0.85 per SD decrease), and stroke in the mother (HR, 1.31). Similar risk factors were found for hemorrhagic stroke including low aerobic fitness (HR, 0.82 per SD increase), high BMI (HR, 1.18 per SD increase) alcohol intoxication (HR, 2.92), diabetes (HR, 2.06), and low annual income (HR, 0.75). The population attributable risks associated with all evaluated risk factors were 69% for ischemic stroke and 88% for hemorrhagic stroke (p < 0.001 for both). Conclusions: In the present study we have shown that several known risk factors for stroke are present already in late adolescence, and that they are independent of each other. The strongest risk factors were low physical fitness, high BMI, diabetes, low annual income and a maternal history of stroke. Several of the aforementioned risk factors are potentially modifiable.

Risk factors of stroke in Western and Asian countries: a systematic review and meta-analysis of prospective cohort studies

Background

There has been an increasing trend in the incidence of stroke worldwide in recent years, and the number of studies focusing on the risk factors for stroke has also increased every year. To comprehensively evaluate the risk factors of stroke identified in prospective Western and Asian cohort studies.

Methods

Population-based cohort studies on stroke were searched in databases (PubMed, EMBASE, Web of Science, Google Scholar, etc.), and the library of the Third Military Medical University was manually searched for relevant information. A meta-analysis of Western and Asian studies on risk factors was performed. The pooled hazard ratios (HRs) with 95% confidence intervals (CIs) were calculated to assess the final group of cohort studies.

Results

After screening, 22 prospective cohort studies were included in the analyses of this investigation. Two factors, smoking and alcohol consumption, showed statistically significant differences between Western and Asian populations, and the results were as follows (W/A): 2.05 (95% CI, 1.68 ~ 2.49)/1.27 (95% CI, 1.04 ~ 1.55) and 0.89 (95% CI, 0.76 ~ 1.04)/1.28 (95% CI, 1.07 ~ 1.53). The factor BMI = 18.5-21.9 kg/m² showed statistically significant differences only in Western populations, 0.96 (95% CI, 0.93 ~ 0.99); the factor SBP = 120-139 mm Hg showed statistically significant differences only in Asian populations, 2.29 (95% CI, 1.04 ~ 5.09).

Conclusions

The prevalences of risk factors affect the stroke morbidity in Western and Asian populations, which may be biased by race. The meta-analysis of population-based studies suggests that different preventive measures should be adopted for Western and Asian population groups that are at high risk for stroke.

Electronic supplementary material

The online version of this article (doi:10.1186/1471-2458-14-776) contains supplementary material, which is available to authorized users.

Vascular endothelial growth factor and monocyte chemoattractant protein-1 levels unaltered in symptomatic atherosclerotic carotid plaque patients from north India

We aimed to identify the role of vascular endothelial growth factor (VEGF) and monocyte chemoattractant protein (MCP-1) as a serum biomarker of symptomatic carotid atherosclerotic plaque in North Indian population. Individuals with symptomatic carotid atherosclerotic plaque have high risk of ischemic stroke. Previous studies from western countries have shown an association between VEGF and MCP-1 levels and the incidence of ischemic stroke. In this study, venous blood from 110 human subjects was collected, 57 blood samples of which were obtained from patients with carotid plaques, 38 neurological controls without carotid plaques, and another 15 healthy controls who had no history of serious illness. Serum VEGF and MCP-1 levels were measured using commercially available enzyme-linked immunosorbent assay. We also correlated the data clinically and carried out risk factor analysis based on the detailed questionnaire obtained from each patient. For risk factor analysis, a total of 70 symptomatic carotid plaque cases and equal number of age and sex matched healthy controls were analyzed. We found that serum VEGF levels in carotid plaque patients did not show any significant change when compared to either of the controls. Similarly, there was no significant upregulation of MCP-1 in the serum of these patients. The risk factor analysis revealed that hypertension, diabetes, and physical inactivity were the main correlates of carotid atherosclerosis (p < 0.05). Prevalence of patients was higher residing in urban areas as compared to rural region. We also found that patients coming from mountain region were relatively less vulnerable to cerebral atherosclerosis as compared to the ones residing at non mountain region. On the contrary, smoking, obesity, dyslipidemia, alcohol consumption, and tobacco chewing were not observed as the determinants of carotid atherosclerosis risk in North India (p > 0.05). We conclude that the pathogenesis of carotid plaques may progress independent of these inflammatory molecules. In parallel, risk factor analysis indicates hypertension, diabetes, and sedentary lifestyle as the most significant risk factors of ischemic stroke identified in North India. This could be helpful in early identification of subjects at risk for stroke and devising health care strategies.

[Advances in the prevention, diagnosis and therapy of vascular diseases]

Atherosclerosis is a systemic disease affecting the coronary, carotid, intracerebral, renal and peripherial arteries. The early morphological and functional impairments could be detected in the second or third decades of life and their progression depend on the number and severity of risk factors and individual susceptility. Although the vascular risk factors (smoking, overweight, age, unhealthy diet, lack of physical exercise, hypertension, diabetes mellitus, chronic kidney disease and dyslipidemia) are the same and common in the different vascular diseases, the present clinical routine artificially classifies the diagnosis and therapy of different vascular diseases into different subfields of medicine with the negative impact of possible polypragmasia. Recently, worldwide health surveys (e.g. REACH registry) have proven the usefulness of a holistic approach in the diagnosis and therapy of multiorgan-affected vascular patients. This review summarizes the multidisciplinary advances and future perspective of vascular diseases.

Heart disease and stroke statistics--2011 update: a report from the American Heart Association

Each year, the American Heart Association (AHA), in conjunction with the Centers for Disease Control and Prevention, the National Institutes of Health, and other government agencies, brings together the most up-to-date statistics on heart disease, stroke, other vascular diseases, and their risk factors and presents them in its Heart Disease and Stroke Statistical Update. The Statistical Update is a valuable resource for researchers, clinicians, healthcare policy makers, media professionals, the lay public, and many others who seek the best national data available on disease morbidity and mortality and the risks, quality of care, medical procedures and operations, and costs associated with the management of these diseases in a single document. Indeed, since 1999, the Statistical Update has been cited more than 8700 times in the literature (including citations of all annual versions). In 2009 alone, the various Statistical Updates were cited ≈1600 times (data from ISI Web of Science). In recent years, the Statistical Update has undergone some major changes with the addition of new chapters and major updates across multiple areas. For this year’s edition, the Statistics Committee, which produces the document for the AHA, updated all of the current chapters with the most recent nationally representative data and inclusion of relevant articles from the literature over the past year and added a new chapter detailing how family history and genetics play a role in cardiovascular disease (CVD) risk. Also, the 2011 Statistical Update is a major source for monitoring both cardiovascular health and disease in the population, with a focus on progress toward achievement of the AHA’s 2020 Impact Goals. Below are a few highlights from this year’s Update.

Childhood IQ and social factors on smoking behaviour, lung function and smoking-related outcomes in adulthood: Linking the Scottish Mental Survey 1932 and the Midspan studies

OBJECTIVE

To investigate the associations of childhood IQ and adult social factors, and smoking behaviour, lung function (forced expiratory volume in one second; FEV(1)), and smoking-related outcomes in adulthood.

DESIGN

Retrospective cohort study.

METHOD

Participants were from the Midspan prospective studies conducted on Scottish adults in the 1970s. The sample consisted of 938 Midspan participants born in 1921 who were successfully matched with their cognitive ability test results on the Scottish Mental Survey 1932.

RESULTS

Structural equation modelling showed that age 11 IQ was not directly associated with smoking consumption, but that IQ and adult social class had indirect effects on smoking consumption via deprivation category. The influence of IQ on FEV(1) was partly indirect via social class. Gender influenced smoking consumption and also IQ and social class. There was a 21% higher risk of having a smoking-related hospital admission, cancer, or death during 25 years of follow-up for each standard deviation disadvantage in IQ. Adjustment for adult social class, deprivation category, and smoking reduced the association to 10%.

CONCLUSION

Childhood IQ was associated with social factors which influenced lung function in adulthood, but was not associated directly with smoking consumption. In future studies, it is important to consider other pathways which may account for variance in the link between childhood IQ and health in later life.

Parental occurrence of stroke and risk of stroke in their children: the Framingham study

BACKGROUND

Data relating parental history of stroke to stroke risk in offspring remain surprisingly inconsistent, largely because of heterogeneity of study design and the absence of verified, as opposed to historical, data on parental stroke status.

METHODS AND RESULTS

We determined whether prospectively verified parental occurrence of stroke increased incident stroke risk among offspring in a community-based sample by studying 3443 stroke-free Framingham offspring (53% female; mean age, 48+/-14 years) with verified parental stroke status (by 65 years of age) who attended the first, third, fifth, and/or seventh offspring examinations and were followed up for up to 8 years after each baseline examination. Over up to 11,029 such person-observation periods (77,534 person-years), we documented 106 parental strokes by 65 years of age and 128 offspring strokes (74 parental and 106 offspring strokes were ischemic). Using multivariable Cox models adjusted for age, sex, sibship, and baseline stroke risk factors, we observed that parental stroke, both all stroke generally and ischemic stroke specifically, was associated with an increased risk of incident stroke of the same type in the offspring (hazard ratio, 2.79; 95% confidence interval, 1.68 to 4.66; P<0.001 for all stroke; and hazard ratio, 3.15; 95% confidence interval, 1.69 to 5.88; P<0.001 for ischemic stroke). This was true for both maternal and paternal stroke.

CONCLUSIONS

Documented parental stroke by 65 years of age was associated with a 3-fold increase in risk of offspring stroke. This increased risk persisted after adjustment for conventional stroke risk factors. Thus, verified parental stroke may serve as a clinically useful risk marker of an individual's propensity to stroke.

Principles of designing a cohort study in orthopaedics

A well-designed and executed prospective cohort study can provide high-quality evidence in the evaluation of the effectiveness of surgical interventions. In designing a cohort study to evaluate orthopaedic interventions, it is important to recognize the limitations of the design as well as the methodological features that can be incorporated to strengthen the validity of the conclusions. In this article, we discuss the importance of the appropriate selection of participants for a control group, the management of confounders, the selection of outcomes with established measurement properties (reliability, validity, and sensitivity to change), the blinded assessment of outcomes, and the impact of nonparticipants and patients lost to follow-up.

Regional obesity as a health hazard in men--prospective studies

Cross-sectional studies have shown that a central distribution of adipose tissue is associated with increased risk of metabolic complications and cardiovascular morbidity. Four prospective studies in men are reviewed and they consistently indicate that central adipose tissue distribution is a risk factor for coronary heart disease (CHD) and its predictive contribution seems almost to be in the same order as for the major risk factors for CHD. In one study there is an indication of decreasing predictive power of central adipose tissue distribution for CHD with increasing age. Abdominal adipose tissue distribution is also a risk factor for stroke, diabetes and sickness absenteeism, and for all cause mortality. It seems, however, not to be a predictor of degree of well-being in general. The question of causality is not solved but indices of adipose tissue distribution should be included in future observational and experimental studies in this field.

The associations between obesity, adipose tissue distribution and disease

Recent research has shown the marked differences in association with disease between obesity localized to the abdominal respectively to the gluteal-femoral regions. In this review systematic analyses were performed of the associations between obesity (body mass index, BMI) or abdominal obesity (increased waist-over-hip circumference ratio, WHR) on the one hand, and a number of disease end points, and their risk factors, as well as other factors on the other, WHR was associated with cardiovascular disease, premature death, stroke, non-insulin-dependent diabetes mellitus and female carcinomas. In contrast, BMI tended to be negatively correlated to cardiovascular disease, premature death, and stroke, but positively to diabetes. The established risk factors for these end points were found to correlate to WHR, while this was often not the case with BMI. BMI was positively correlated only to insulin, triglycerides and blood pressure. Together with diabetes mellitus, this seems to constitute a metabolic group of conditions which are thus associated with BMI. Androgens (in women), and perhaps cortisol, seem to be positively, and progesterone negatively correlated to WHR. The WHR was also positively associated with sick leave, several psychological maladjustments, psychosomatic and psychiatric disease. Attempts were made to interpret these findings. In a first alternative an elevation of FFA concentration, produced from abdominal adipose tissue, was considered to be the trigger factor for the pathologic aberrations associated with abdominal distribution of body fat. When obesity is added, the metabolic aberrations may be exaggerated. In a second alternative adrenal cortex hyperactivity was tested as the cause. When combined with the FFA hypothesis, this might explain many but not all of the findings. It seems possible to produce an almost identical syndrome in primates by defined experimental stress. Women with high WHR were found to have a number of symptoms of poor coping to stress. It was therefore suggested that part of the background to this syndrome might be a hypothalamic arousal syndrome developing with stress. It was concluded that obesity and abdominal distribution of adipose tissue constitute two separate entities with different pathogenesis, clinical consequences and probably treatment.

Predictors of stroke in the elderly

Hypertension, diabetes mellitus, coronary heart disease and cigarette smoking have repeatedly been identified as risk factors for stroke in young and middle-aged individuals. In order to find predicting factors for stroke in the elderly we assessed health characteristics in 55 stroke victims in the age range 65-75 years (mean 70.7 +/- 2.7) allocated to our stroke unit at Ostra University Hospital in Gothenburg. For comparison we used data from 2,009 individuals participating in the ongoing longitudinal population study "70-year-old people in Gothenburg, Sweden". Among the stroke victims we found a higher prevalence of hypertension (63.5% vs. 27.8%, p less than 0.001), diabetes mellitus (21.8% vs. 6.2%, p less than 0.001) and a history of previous myocardial infarction (12.7% vs. 4.8%, p less than 0.01), thus confirming previous findings. There was no difference with regard to smoking habits (32.7% vs. 27.5%, NS), which is at variance with findings in the young and middle-aged.

Regional obesity and serum lipids in European women born in 1948. A multicenter study

In five different cities in four European countries, women born in 1948 were randomly selected. Anthropometric measurements (i.e. circumferences and skinfolds) were taken. Serum lipids were determined in one laboratory. Different levels of waist circumferences gave different averages and distribution of waist/hip ratio, which confirms the need of precise standardization of these measurements. Women in southern parts of Europe were more overweight than in Northern Europe (partly due to selection bias in Naples) and, when adjusted for that, southern women had a more central distribution of fat (higher waist/thigh, lower triceps/subscapula). When data were pooled, circumference ratios were positively correlated with triglycerides and total cholesterol and negatively with HDL cholesterol. Occupation of husband and body mass index were associated with fat distribution and triglycerides and HDL cholesterol. In multiple regression fat distribution was still correlated with serum lipids but differences in serum lipids between countries did not diminish.

Gene variants associated with ischemic stroke: the cardiovascular health study

BACKGROUND AND PURPOSE

The purpose of this study was to determine whether 74 single nucleotide polymorphisms (SNPs), which had been associated with coronary heart disease, are associated with incident ischemic stroke.

METHODS

Based on antecedent studies of coronary heart disease, we prespecified the risk allele for each of the 74 SNPs. We used Cox proportional hazards models that adjusted for traditional risk factors to estimate the associations of these SNPs with incident ischemic stroke during 14 years of follow-up in a population-based study of older adults: the Cardiovascular Health Study (CHS).

RESULTS

In white CHS participants, the prespecified risk alleles of 7 of the 74 SNPs (in HPS1, ITGAE, ABCG2, MYH15, FSTL4, CALM1, and BAT2) were nominally associated with increased risk of stroke (one-sided P<0.05, false discovery rate=0.42). In black participants, the prespecified risk alleles of 5 SNPs (in KRT4, LY6G5B, EDG1, DMXL2, and ABCG2) were nominally associated with stroke (one-sided P<0.05, false discovery rate=0.55). The Val12Met SNP in ABCG2 was associated with stroke in both white (hazard ratio, 1.46; 90% CI, 1.05 to 2.03) and black (hazard ratio, 3.59; 90% CI, 1.11 to 11.6) participants of CHS. Kaplan-Meier estimates of the 10-year cumulative incidence of stroke were greater among Val allele homozygotes than among Met allele carriers in both white (10% versus 6%) and black (12% versus 3%) participants of CHS.

CONCLUSIONS

The Val12Met SNP in ABCG2 (encoding a transporter of sterols and xenobiotics) was associated with incident ischemic stroke in white and black participants of CHS.

Does the relationship between waist circumference, morbidity and mortality depend on measurement protocol for waist circumference?

There is currently no consensus regarding the optimal protocol for measurement of waist circumference (WC), and no scientific rationale is provided for any of the WC protocols recommended by leading health authorities. A panel of experts conducted a systematic review of 120 studies (236 samples) to determine whether measurement protocol influenced the relationship of WC with morbidity of cardiovascular disease (CVD) and diabetes and with mortality from all causes and from CVD. Statistically significant associations with WC were reported for 65% (152) of the samples across all outcomes combined. Common WC protocols performed measurement at the minimal waist (33%), midpoint (26%) and umbilicus (27%). Non-significant associations were reported for 27% (64) of the samples. Most of these protocols measured WC at the midpoint (36%), umbilicus (28%) or minimal waist (25%). Significant associations were observed for 17 of the remaining 20 samples, but these were not significant when adjustment was made for covariates. For these samples, the most common WC protocols were the midpoint (35%) and umbilicus (30%). Similar patterns of association between the outcomes and all WC protocols were observed across sample size, sex, age, race and ethnicity. Our findings suggest that WC measurement protocol has no substantial influence on the association between WC, all-cause and CVD mortality, CVD and diabetes.

International Day for the Evaluation of Abdominal Obesity (IDEA): a study of waist circumference, cardiovascular disease, and diabetes mellitus in 168,000 primary care patients in 63 countries

BACKGROUND

Abdominal adiposity is a growing clinical and public health problem. It is not known whether it is similarly associated with cardiovascular disease (CVD) and diabetes mellitus in different regions around the world, and thus whether measurement of waist circumference (WC) in addition to body mass index (BMI) is useful in primary care practice.

METHODS AND RESULTS

Randomly chosen primary care physicians in 63 countries recruited consecutive patients aged 18 to 80 years on 2 prespecified half days. WC and BMI were measured and the presence of CVD and diabetes mellitus recorded. Of the patients who consulted the primary care physicians, 97% agreed to participate in the present study. Overall, 24% of 69,409 men and 27% of 98,750 women were obese (BMI > or = 30 kg/m2). A further 40% and 30% of men and women, respectively, were overweight (BMI 25 to 30 kg/m2). Increased WC (> 102 for men and > 88 cm for women) was recorded in 29% and 48%, CVD in 16% and 13%, and diabetes mellitus in 13% and 11% of men and women, respectively. A statistically significant graded increase existed in the frequency of CVD and diabetes mellitus with both BMI and WC, with a stronger relationship for WC than for BMI across regions for both genders. This relationship between WC, CVD, and particularly diabetes mellitus was seen even in lean patients (BMI < 25 kg/m2).

CONCLUSIONS

Among men and women who consulted primary care physicians, BMI and particularly WC were both strongly linked to CVD and especially to diabetes mellitus. Strategies to address this global problem are required to prevent an epidemic of these major causes of morbidity and mortality.

Biomarkers related to aging in human populations

Biomarkers are increasingly employed in empirical studies of human populations to understand physiological processes that change with age, diseases whose onset appears linked to age, and the aging process itself. In this chapter, we describe some of the most commonly used biomarkers in population aging research, including their collection, associations with other markers, and relationships to health outcomes. We discuss biomarkers of the cardiovascular system, metabolic processes, inflammation, activity in the hypothalamic-pituitary axis (HPA) and sympathetic nervous system (SNS), and organ functioning (including kidney, lung, and heart). In addition, we note that markers of functioning of the central nervous system and genetic markers are now becoming part of population measurement. Where possible, we detail interrelationships between these markers by providing correlations between high risk levels of each marker from three population-based surveys: the National Health and Nutrition Examination Survey (NHANES) III, NHANES 1999-2002, and the MacArthur Study of Successful Aging. NHANES III is used instead of NHANES 1999-2002 when specific markers of interest are available only in NHANES III and when we examine the relationship of biomarkers to mortality which is only known for NHANES III. We also describe summary measures combining biomarkers across systems. Finally, we examine associations between individual markers and mortality and provide information about biomarkers of growing interest for future research in population aging and health.

Sex Differences in Heritability of Ischemic Stroke

Background and Purpose— Using data from Oxfordshire, UK, we recently showed that women are more likely than men to have a family history of stroke in female versus male first degree relatives. To test the generalizability of this finding, we did a comprehensive systematic review of all available published and unpublished data.

Methods— Studies were included in the present review if they reported the frequency of family history of stroke in relation to sex of parent or proband. Where necessary, we contacted authors of studies to obtain unpublished data. Data from the Oxford Vascular Study (OXVASC) and 3 other Oxford cohorts (1925 patients) were secondarily pooled with the data from other studies.

Results— We obtained data from 18 studies (7941 patients), including unpublished data from 7 studies. Female probands were slightly more likely to have a parental history of stroke than male probands (pooled OR=1.15; 95% CI: 1.03 to 1.29; P (sig) =0.028; P (het) =0.45). Maternal history of stroke was more common than paternal history (pooled OR=1.25; 1.15 to 1.37; P (sig) <0.00001; P (het) =0.12). However, the maternal excess was only present in female probands (pooled OR=1.47; 1.27 to 1.70; P (sig) <0.00001; P (het) =0.11). In contrast, male probands were no more likely to have maternal than paternal history of stroke (pooled OR=1.02; 0.88 to 1.17, P (sig) =0.43; P (het) =0.09).

Conclusions— Women with stroke are more likely than men to have a parental history of stroke, which is accounted for by an excess maternal history of stroke. This finding could be explained by sex-specific genetic, epigenetic, or nongenetic mechanisms.

The interaction of genes and smoking on forced expiratory volume: a classic twin study

BACKGROUND

Genetic influences on lung function as measured by FEV1 have been reported from twin and family studies. The aims of this study were to estimate heritability of the ratio of measured FEV1 (mFEV1) to expected FEV(1) (eFEV1) in a white population, and to examine the interaction between genetic factors and smoking on this ratio.

METHODS AND SUBJECTS

The sample consisted of unselected monozygotic (MZ) and dizygotic (DZ) twin pairs from the TwinsUK registry. FEV1 was measured with a spirometer, and mFEV1/eFEV1 ratio was calculated.

RESULTS

A total of 475 MZ and 1,054 DZ twin pairs participated (mean age, 47 years; range, 18 to 84 years). mFEV1/eFEV1 ratio was 0.057 lower in smokers than nonsmokers (p < 0.0001). The difference in the correlation for mFEV1/eFEV1 ratio between MZ and DZ twin pairs was 0.32 in nonsmokers and 0.19 in current smokers, suggesting a significant genetic influence on lung function that was modified in current smokers. Using structural equation modeling, the heritability estimate for mFEV1/eFEV1 ratio was found to be 66% (95% confidence interval [CI], 59 to 72%) in nonsmokers but significantly reduced to 32% (95% CI, 12 to 53%) in current smokers. However, there was no clear difference in the heritability of mFEV1/eFEV1 ratio between nonsmokers and ex-smokers.

CONCLUSION

Genes are the major influence on the variability of mFEV1/eFEV1 ratio in nonsmokers. However, this strong genetic influence is strongly modified by an interaction with cigarettes.

Age and follow-up time affect the prognostic value of the ECG and conventional cardiovascular risk factors for stroke in adult men

OBJECTIVES

To explore whether the predictive power of mid-life ECG abnormalities and conventional cardiovascular risk factors for future stroke change over a 30-year follow-up period, and whether a repeated examination improves their predictive power.

DESIGN AND SETTING

Longitudinal population-based study.

PARTICIPANTS

2,322 men aged 50 years, with a follow-up period of 30 years. 1,221 subjects were re-examined at age 70 years

MAIN OUTCOME MEASURE

Risk for fatal and non-fatal stroke during three decades of follow-up. Investigations included resting ECG and traditional cardiovascular risk factors.

RESULTS

When measured at age 50 years, ST segment depression and T wave abnormalities, together with ECG-left ventricular hypertrophy, were of importance only during the first 20 years, but regained importance when re-measured at age 70 years. Blood pressure was a significant predictor for stroke over all three decades of follow-up. In elderly people only, there is evidence that apolipoprotein A1 may protect from future stroke.

CONCLUSION

Mid-life values for blood pressure and ECG abnormalities retain their predictive value over long follow-up periods even though they improved in predictive power when re-measured in elderly people. Despite lower prevalence, ECG abnormalities had greater impact at age 50 years than at age 70 years. By contrast, apolipoprotein A1 was protective for future stroke only at age 70 years.

Excess body weight and risk of first-ever acute ischaemic non-embolic stroke in elderly subjects

In a population-based case-control study we assessed the association between obesity and acute ischaemic/non-embolic stroke. A total of 163 patients aged older than 70 years (88 men and 75 women) admitted due to a first-ever-in-a-lifetime acute ischaemic/non-embolic stroke and 166 volunteers (87 men and 79 women) without a history of cardiovascular disease were included. The association of stroke with body mass index (BMI) or waist circumference (WC) was determined by multivariate logistic regression modelling after adjusting for potential confounding factors. Overweight and obesity were more prevalent amongst stroke patients compared to controls. Subjects with a BMI > or = 30 kg/m2 had 2.5-times higher odds to suffer an acute ischaemic/non-embolic stroke compared to subjects within the lowest BMI category of 18.5-20.9 kg/m2. Analysis of interaction showed that in the presence of overweight and/or obesity (classified as a BMI > or = 25 kg/m2 and/or a WC > 102 cm in men and > 88 cm in women) the inverse relationship between HDL cholesterol and ischaemic/non-embolic stroke was negated. Excess weight is associated with an increased risk of acute ischaemic/non-embolic stroke in elderly individuals independently of concurrent metabolic derangements. Moreover, in the presence of obesity, HDL cholesterol loses its protective effect against ischaemic stroke.

Lung function and ischemic stroke incidence: the Atherosclerosis Risk in Communities study

BACKGROUND

Few studies have examined the relation between lung function and ischemic stroke incidence; none have studied African Americans.

METHODS

We followed 13,842 middle-aged adults initially free of stroke and coronary heart disease and observed 472 incident ischemic strokes over 13 years. Quartiles of FEV(1) as a percentage of predicted value (FEV(1)PP) and FVC as a percentage of a predicted value (FVCPP) were used as the indicators of lung function.

RESULTS

In the age-, race-, gender-, and education-adjusted models, both lung function measures were significantly inversely related to ischemic stroke incidence (linear trend for FEV(1)PP, p < 0.01; linear trend for FVCPP, p < 0.01), but adjustment for possible confounders attenuated these relations. For white subjects, a significant inverse relation remained even after full adjustment (relative hazards [RH] across FEV(1)PP quartiles (lowest to highest) were 1.59, 1.52, 1.26, and 1.00; and for FVCPP quartiles were 1.56, 1.80, 1.09, and 1.00 [trend for both, p < 0.05]). There was no association for African Americans (RH across FEV(1)PP and FVCPP quartiles were 0.74, 0.89, 0.73, 1.00 [linear trend, p = 0.27] and 0.81, 1.07, 0.61, 1.00 [linear trend, p = 0.75], respectively). An inverse relation between lung function and ischemic stroke was also observed among white subjects who never smoked (FEV(1)PP) or had no respiratory symptoms (both FEV(1)PP and FVCPP) but not among their African-American counterparts.

CONCLUSIONS

Among white subjects, participants with impaired lung function have a modestly higher risk of ischemic stroke even if they have never smoked nor had respiratory symptoms.

The relative strength of C-reactive protein and lipid levels as determinants of ischemic stroke compared with coronary heart disease in women

OBJECTIVES

We sought to determine the relative strength of high-sensitivity C-reactive protein (hs-CRP) and lipid levels as markers for future ischemic stroke compared with coronary heart disease (CHD) in women.

BACKGROUND

Although hs-CRP and lipid levels are established risk determinants for vascular disease, the relative strength of these biomarkers for ischemic stroke compared with CHD is uncertain.

METHODS

Among 15,632 initially healthy women who were followed for a 10-year period, we compared hs-CRP, total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), non-high-density lipoprotein cholesterol (non-HDL-C), high-density lipoprotein cholesterol (HDL-C), apolipoproteins A-I and B100, and lipid ratios as determinants of ischemic stroke compared with CHD.

RESULTS

After adjustment for age, smoking status, blood pressure, diabetes, and obesity, the hazard ratios (HRs) and 95% confidence intervals (CIs) for the third versus the first tertile for future ischemic stroke compared with CHD were, respectively, 1.91 (95% CI 1.13 to 3.21) and 2.26 (95% CI 1.64 to 3.12) for TC, 1.29 (95% CI 0.83 to 2.02) and 2.09 (95% CI 1.53 to 2.85) for LDL-C, 0.57 (95% CI 0.36 to 0.92) and 0.38 (95% CI 0.27 to 0.52) for HDL-C, 1.72 (95% CI 1.03 to 2.86) and 2.93 (95% CI 2.04 to 4.21) for non-HDL-C, and 2.76 (95% CI 1.51 to 5.05) and 1.66 (95% CI 1.17 to 2.34) for hs-CRP. Of the lipid ratios, that of TC to HDL-C had the largest HR for both future ischemic stroke and CHD (HR 1.95 [95% CI 1.16 to 3.26] and 4.20 [95% CI 2.79 to 6.32], respectively).

CONCLUSIONS

In this large prospective cohort of initially healthy women, lipid levels are significant risk determinants for ischemic stroke, but with a magnitude of effect smaller than that observed for CHD. High-sensitivity CRP associates more closely with ischemic stroke than with CHD. Concomitant evaluation of lipid levels and hs-CRP may improve risk assessment for stroke as well as CHD. (The Women's Health Study; http://www.clinicaltrials.gov/ct/show/NCT00000479/; NCT00000479).

Primary Prevention of Ischemic Stroke

Background and Purpose— This guideline provides an overview of the evidence on various established and potential stroke risk factors and provides recommendations for the reduction of stroke risk.

Methods— Writing group members were nominated by the committee chair on the basis of each writer’s previous work in relevant topic areas and were approved by the American Heart Association Stroke Council’s Scientific Statement Oversight Committee. The writers used systematic literature reviews (covering the time period since the last review published in 2001 up to January 2005), reference to previously published guidelines, personal files, and expert opinion to summarize existing evidence, indicate gaps in current knowledge, and when appropriate, formulate recommendations based on standard American Heart Association criteria. All members of the writing group had numerous opportunities to comment in writing on the recommendations and approved the final version of this document. The guideline underwent extensive peer review before consideration and approval by the AHA Science Advisory and Coordinating Committee.

Results— Schemes for assessing a person’s risk of a first stroke were evaluated. Risk factors or risk markers for a first stroke were classified according to their potential for modification (nonmodifiable, modifiable, or potentially modifiable) and strength of evidence (well documented or less well documented). Nonmodifiable risk factors include age, sex, low birth weight, race/ethnicity, and genetic factors. Well-documented and modifiable risk factors include hypertension, exposure to cigarette smoke, diabetes, atrial fibrillation and certain other cardiac conditions, dyslipidemia, carotid artery stenosis, sickle cell disease, postmenopausal hormone therapy, poor diet, physical inactivity, and obesity and body fat distribution. Less well-documented or potentially modifiable risk factors include the metabolic syndrome, alcohol abuse, drug abuse, oral contraceptive use, sleep-disordered breathing, migraine headache, hyperhomocysteinemia, elevated lipoprotein(a), elevated lipoprotein-associated phospholipase, hypercoagulability, inflammation, and infection. Data on the use of aspirin for primary stroke prevention are reviewed.

Conclusion— Extensive evidence is available identifying a variety of specific factors that increase the risk of a first stroke and providing strategies for reducing that risk.

Single gene disorders causing ischaemic stroke

Stroke is the third most common cause of death and the leading cause of long-term neurological disability in the world. Conventional vascular risk factors for stroke contribute approximately to only forty to fifty percent of stroke risk. Genetic factors may therefore contribute to a significant proportion of stroke and may be polygenic, monogenic or multi-factorial. Monogenic (single gene) disorders may potentially account for approximately one percent of all ischaemic stroke. Monogenic stroke disorders include conditions such as cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL), cerebral autosomal recessive arteriopathy with subcortical infarcts and leukoencephalopathy (CARASIL) and hereditary endotheliopathy, retinopathy, nephropathy and stroke (HERNS). In addition, other monogenic conditions such as sickle cell and Fabry disease also lead to stroke. These monogenic disorders cause either small vessel or large vessel stroke (or a combination of both) and serve as useful models for understanding and studying conventional stroke and cerebrovascular disease and its accompaniments such as vascular dementia.

Long-term risk factors for stroke: twenty-eight years of follow-up of 7457 middle-aged men in Göteborg, Sweden

BACKGROUND AND PURPOSE

To estimate the predictive value of risk factors for stroke measured in midlife over follow-up extending through 28 years.

METHODS

A cohort of 7457 men 47 to 55 years of age and free of stroke at baseline year 1970 were examined. Risk of stroke was analyzed for the entire period and for 0 to 15, 16 to 21, and 22 to 28 years of follow-up using age-adjusted and multiple Cox regression analyses.

RESULTS

Age, diabetes, and high blood pressure were independently associated with increased risk of stroke for the entire 28 years and for each of the periods. Previous transient ischemic attacks, atrial fibrillation, history of chest pain, smoking, and psychological stress were independently related to stroke for the entire follow-up period and also during the first 1 or 2 successive periods. Family history of stroke or of coronary disease carried no independent prognostic information, nor did serum cholesterol. Elevated body mass index predicted stroke during the later part of the follow-up and so did (almost) low physical activity during leisure time, together with antihypertensive medication at baseline.

CONCLUSIONS

High blood pressure and diabetes retain their importance as stroke risk factors also over an extended follow-up into old age. A family history of cardiovascular disease was not significantly related to outcome. Transient ischemic attacks, atrial fibrillation, stress, smoking, and a history of chest pain were associated with outcome only for the first or the first 2 periods. High body mass index and antihypertensive medication at baseline emerged as risk factors in the second and third decades.

Risk factors for stroke in type 2 diabetes mellitus

Stroke is a serious complication of diabetes but the risk factors for stroke in these patients are not fully defined. The aim of this retrospective study was to investigate the risk factors for stroke in patients with type 2 diabetes mellitus (T2DM). The group comprised 208 patients with T2DM, and the mean duration of follow-up was seven years (range 4-11 years). The incidence of stroke was investigated according to lymphocyte proliferation in response to insulin. Using cimetidine to inhibit cells with histamine receptors and indometacin to inhibit prostaglandin-synthesising cells, a higher incidence of stroke was found in patients with indirect cell-mediated immunity to insulin. Therefore, one of the risk factors for stroke in patients with T2DM is high activity of cells with histamine receptors and prostaglandin-synthesising cells. These cells suppress cell-mediated immunity to insulin and may have a role in promoting the development of insulin resistance.

Prevalence of Stroke and Vascular Risk Factors among First-Degree Relatives of Stroke Patients and Control Subjects

BACKGROUND

Genetic and environmental factors may be of importance for stroke risk. We assessed the prevalence of stroke and vascular risk factors among first-degree relatives and spouses of stroke patients and control subjects.

METHODS

As a part of the Lund Stroke Register study, we asked 925 consecutive patients with first-ever stroke and 286 control subjects to complete a questionnaire about all their first-degree relatives and spouses. The questionnaires addressed whether these relatives had been affected by stroke or TIA, hypertension, heart disease, diabetes mellitus, and if they were smokers.

RESULTS

A total of 606 patients and 261 control subjects returned the questionnaire, providing information on 4,972 first-degree relatives and 738 spouses. The prevalence of stroke or TIA was 12.3% among first-degree relatives of patients and 7.5% among first-degree relatives of control subjects (OR 1.74, 95% CI 1.36-2.22). Corresponding results for hypertension were 21.0 and 16.7% (OR 1.33, 95% CI 1.10-1.60). The prevalences of heart disease, diabetes mellitus and smoking did not differ significantly between first-degree relatives of patients and control subjects. Spouses of patients and control subjects had similar prevalences of stroke or TIA and vascular risk factors.

CONCLUSIONS

The prevalences of stroke or TIA and hypertension are higher among first-degree relatives of stroke patients than among first-degree relatives of control subjects. This, and the lack of differences between spouses of patients and control subjects, indicates that an increased risk of stroke may in part be explained by heritability of hypertension.

Hypertension and stroke in centenarians, Okinawa, Japan

OBJECTIVE

To investigate the relationship between a history of hypertension, cigarette smoking and alcohol intake and the lifetime prevalence of stroke in the oldest-old population.

DESIGN

A cross-sectional study.

SUBJECTS

All of the Japanese centenarians in the Okinawa Prefecture (266 men and 1,378 women).

METHODS

Okinawa Prefectural Government conducted health surveys among all of the centenarians in Okinawa. The variables used for analysis were sex, history of stroke, age at the first diagnosis of stroke, history of hypertension, cigarette smoking and alcohol intake. We used multiple logistic regression analysis taking the history of stroke as the dependent variable.

RESULTS

The lifetime prevalence value for stroke was 11.0% in Japanese centenarians. Hypertension was independently associated with an increased lifetime prevalence of stroke (adjusted odds ratio = 2.97 and 95% confidence interval: 2.16-4.08). There was no material relationship between sex, cigarette smoking, oralcohol intake and the prevalence of stroke. When the lifetime prevalence of stroke was divided according to whether stroke had been diagnosed for the first time at the age of 90 years or less or over the age of 90, a significant positive association between hypertension and stroke was more pronounced in centenarians with a diagnosis of stroke at the age of 90 years or less than in those over the age of 90.

CONCLUSIONS

The findings suggest that hypertension may increase the likelihood of stroke in Japanese centenarians in Okinawa although the association between hypertension and stroke was more pronounced in those having stroke at 90 years or younger.

Promoter polymorphisms in the nitric oxide synthase 3 gene are associated with ischemic stroke susceptibility in young black women

BACKGROUND AND PURPOSE

Endothelial nitric oxide exerts a variety of protective effects on endothelial cells and blood vessels, and therefore the nitric oxide synthase 3 gene (NOS3) is a logical candidate gene for stroke susceptibility.

METHODS

We used the population-based Stroke Prevention in Young Women case-control study to assess the association of five NOS3 polymorphisms in 110 cases (46% black) with ischemic stroke and 206 controls (38% black), 15 to 44 years of age. Polymorphisms included 3 single nucleotide polymorphisms (SNPs) in the promoter region (-1468 T>A, -922 G>A, -786 T>C), 1 SNP in exon 7 (G894T), and 1 insertion/deletion polymorphism within intron 4.

RESULTS

Significant associations with both the -922 G>A and -786 T>C SNPs with ischemic stroke were observed in the black, but not the white, population. This association was attributable to an increased prevalence of the -922 A allele (OR=3.0, 95% CI=1.3 to 6.8; P=0.005) and the -786 T allele (OR=2.9, 95% CI=1.3 to 6.4; P=0.005) in cases versus controls. These 2 SNPs were in strong linkage disequilibrium (D'=1.0), making it impossible to determine, within the confines of this genetic study, whether 1 or both of these polymorphisms are functionally related to NOS3 expression. Two sets of haplotypes were also identified, 1 of which may confer an increased susceptibility to stroke in blacks, whereas the other appears to be protective.

CONCLUSIONS

Promoter variants in NOS3 may be associated with ischemic stroke susceptibility among young black women.