Smoking is Associated with Silent Cerebrovascular Disease in a High-Risk Japanese Community-Dwelling Population

Predictive value of P wave parameters, indices, and a novel electrocardiographic marker for silent cerebral infarction and future cerebrovascular events

BACKGROUND

Silent cerebral infarction (SCI) is a neuronal injury without a clinically apparent stroke or transient ischaemic attack. Left atrial cardiomyopathy is closely associated with SCI. P wave changes in the electrocardiogram (ECG) provide significant information about the development of atrial cardiomyopathy. This study evaluated the role of P wave parameters and indices and a novel ECG parameter in predicting SCI, future cerebrovascular events, and atrial fibrillation/flutter.

MATERIALS AND METHODS

A total of 272 patients were retrospectively screened and divided into two groups according to SCI. Cerebrovascular events and atrial fibrillation/flutter were defined as the study's outcomes. P wave parameters, indices, and a novel ECG parameter called the P wave ratio (PWR) were calculated from ECGs, and the relationship between SCI and outcomes was investigated.

RESULTS

The maximum P wave duration (PWD), P wave dispersion (PWdisp), PWD measured from the D2 lead (PWDD2), P wave peak time measured from the D2 lead (PWPTD2), PWPT measured from the V1 lead (PWPTV1), and P wave terminal force (PWTFV1) were significantly longer in the SCI group. Both partial and advanced inter atrial block (IAB) were significantly high in the SCI group. The novel parameter P wave ratio (PWR) was significantly longer in the SCI group (0.55 ± 0.08 vs. 0.46 ± 0.09; p < 0.001). In multivariate regression analysis, PWdisp (OR: 1.101, p < 0.001), PWPTD2 (OR: 1.095, p = 0.017), and PWR (OR: 1.231, p < 0.001) were found to be independent predictors of SCI. Cox regression analysis revealed that the PWR (HR 1.077; 95% CI 1.029-1.128; p = 0.001) was associated with cerebrovascular events and atrial fibrillation/flutter.

CONCLUSION

In our study, we observed that PWR could be a valuable parameter for predicting SCI and future cerebrovascular events.

The effects of chronic smoking on total cerebral blood volume measured by carotid and vertebral artery doppler ultrasonography

PURPOSE

To evaluate the effects of chronic cigarette smoking on total cerebral blood flow in healthy adults by Doppler ultrasonography (US).

METHODS

We evaluated 50 smoker (median age 29) and 50 nonsmoker (median age 28) healthy, 20- to 40-year-old subjects without any cardiovascular and cerebrovascular disease. Peak systolic maximal blood flow velocity (PSV), end-diastolic maximal blood flow velocity (EDV), time-averaged mean blood flow velocity (TAMV), resistance index (RI), and pulsatility index (PI) were measured in the left and right carotid and vertebral arteries, and total cerebral blood flow volume was calculated.

RESULTS

There was no significant difference of smoking rate between genders. Blood pressure and PSV values were similar in both groups. EDV values of internal carotid artery (ICA) and vertebral artery (VA) were lower and RI and PI values were higher in smokers. TAMV, total ICA (-10.8%) and VA (-6%) flow volume, and tCBF (-9.2%) were lower in smokers.

CONCLUSIONS

Doppler US is an effective tool to detect tCBF volume decrease in chronic cigarette smokers. Although minimal, this decrease, as demonstrated here in asymptomatic, healthy people, might be critical in patients with subclinical cerebral arterial insufficiency. © 2017 Wiley Periodicals, Inc. J Clin Ultrasound 45:561-565, 2017.

Hematocrit levels as cardiovascular risk among taxi drivers in Bangkok, Thailand

In Thailand, taxi drivers employed in the informal sector often experience hazardous working conditions. Previous studies revealed that elevated Hematocrit (HCT) is a predictor of cardiovascular disease (CVD) risk. This study assessed factors associated with HCT in taxi drivers to predict their occupational CVD risk factors. A cross-sectional study was conducted on 298 male taxi drivers who joined a health check-up campaign in Bangkok, Thailand. HCT and body mass index were retrieved from participant health check-up files. Self-administered questionnaires assessed demographics, driving mileage, working hours, and lifestyle. Statistical associations were analyzed using stepwise linear regression. Our results showed that obesity (p=0.007), daily alcohol drinking (p=0.003), and current or past smoking (p=0.016) were associated with higher HCT levels. While working hours were not directly associated with HCT levels in the current study, the effect on overworking is statistically arguable because most participants worked substantially longer hours. Our findings suggest that taxi drivers' CVD risk may be increased by their unhealthy work styles. Initiatives to improve general working conditions for taxi drivers should take into account health promotion and CVD prevention. The policy of providing periodic health check-ups is important to make workers in the informal sector aware of their health status.

Cerebral small vessel disease and renal function: systematic review and meta-analysis

Background

The small vessel disease (SVD) that appears in the brain may be part of a multisystem disorder affecting other vascular beds such as the kidney and retina. Because renal failure is associated with both stroke and white matter hyperintensities we hypothesised that small vessel (lacunar) stroke would be more strongly associated with renal failure than cortical stroke. Therefore, we performed a systematic review and meta-analysis to establish first if lacunar stroke was associated with the renal function, and second, if cerebral small vessel disease seen on the MRI of patients without stroke was more common in patients with renal failure.

Methods

We searched Medline and EMBASE for studies in adults with cerebral SVD (lacunar stroke or white matter hyper intensities (WMH) on Magnetic Resonance Imaging (MRI)), in which renal function was assessed (estimated glomerular filtration rate (eGFR) or proteinuria). We extracted data on SVD diagnosis, renal function, demographics and comorbidities. We performed two meta-analyses: first, we calculated the odds of renal impairment in lacunar (small vessel) ischaemic stroke compared to other ischaemic stroke subtypes (non-small vessel disease); and second, we calculated the odds of renal impairment in non-stroke individuals with WMH on MRI compared to individuals without WMH. We then performed a sensitivity analysis by excluding studies with certain characteristics and repeating the meta-analysis calculation.

Results

After screening 11,001 potentially suitable titles, we included 37 papers reporting 32 studies of 20,379 subjects: 15 of stroke patients and 17 of SVD features in non-stroke patients. To diagnose lacunar stroke, 13/15 of the studies used risk factor-based classification (none used diffusion-weighted MRI). 394/1,119 (35%) of patients with lacunar stroke had renal impairment compared with 1,443/4,217 (34%) of patients with non-lacunar stroke, OR 0.88, (95% CI 0.6-1.30). In individuals without stroke the presence of SVD was associated with an increased risk of renal impairment (whether proteinuria or reduced eGFR) OR 2.33 (95% CI 1.80-3.01), when compared to those without SVD. After adjustment for age and hypertension, 15/21 studies still reported a significant association between renal impairment and SVD.

Conclusion

We found no specific association between renal impairment and lacunar stroke, but we did find that in individuals who had not had a stroke, having more SVD features on imaging was associated with a worse renal function, which remained significant after controlling for hypertension. However, this finding does not exclude a powerful co-associate effect of age or vascular risk factor exposure. Future research should subtype lacunar stroke sensitively and control for major risk factors.

Plasma B-type natriuretic peptide is a useful tool for assessing coronary heart disease risk in a Japanese general population

B-type natriuretic peptide (BNP) has been reported to be associated with cardiovascular prognosis in a community-based population. In addition, accumulation of individual cardiovascular risk factors is important in predicting an individual's risk of future cardiovascular disease. However, there have been few reports showing that BNP is a comprehensive marker of the accumulation of cardiovascular risk factors. We studied 1530 community-dwelling subjects without obvious heart diseases or renal dysfunction (mean age 62 ± 15 years; 569 men and 961 women) who participated in an annual health checkup in a rural Japanese community. Coronary heart disease (CHD) risk was estimated, and patients were placed into the following three groups based on the Framingham function: low risk, moderate risk and high risk. The prevalence of moderate- and high-risk subjects for CHD rose in both genders with increasing plasma BNP levels. The area under the receiver operating characteristic curve showed a modest ability of plasma BNP levels to detect these subjects (0.755 and 0.700 for men and women, respectively). The optimal thresholds for the identification of subjects with moderate- and high-risk disease were BNP concentrations of 12.0 and 22.0 pg ml(-1), with sensitivities of 70% and 66% and specificities of 71% and 63% for men and women, respectively. In conclusion, subjects with high plasma BNP levels were at higher risk for CHD in a population without obvious heart disease or renal dysfunction.

The silent and apparent neurological injury in transcatheter aortic valve implantation study (SANITY): concept, design and rationale

Background

The incidence of clinically apparent stroke in transcatheter aortic valve implantation (TAVI) exceeds that of any other procedure performed by interventional cardiologists and, in the index admission, occurs more than twice as frequently with TAVI than with surgical aortic valve replacement (SAVR). However, this represents only a small component of the vast burden of neurological injury that occurs during TAVI, with recent evidence suggesting that many strokes are clinically silent or only subtly apparent. Additionally, insult may manifest as slight neurocognitive dysfunction rather than overt neurological deficits. Characterisation of the incidence and underlying aetiology of these neurological events may lead to identification of currently unrecognised neuroprotective strategies.

Methods

The Silent and Apparent Neurological Injury in TAVI (SANITY) Study is a prospective, multicentre, observational study comparing the incidence of neurological injury after TAVI versus SAVR. It introduces an intensive, standardised, formal neurologic and neurocognitive disease assessment for all aortic valve recipients, regardless of intervention (SAVR, TAVI), valve-type (bioprosthetic, Edwards SAPIEN-XT) or access route (sternotomy, transfemoral, transapical or transaortic). Comprehensive monitoring of neurological insult will also be recorded to more fully define and compare the neurological burden of the procedures and identify targets for harm minimisation strategies.

Discussion

The SANITY study undertakes the most rigorous assessment of neurological injury reported in the literature to date. It attempts to accurately characterise the insult and sustained injury associated with both TAVI and SAVR in an attempt to advance understanding of this complication and associations thus allowing for improved patient selection and procedural modification.

Association between common genetic variants of α2A-, α2B- and α2C-adrenoceptors and the risk of silent brain infarction

Silent brain infarction (SBI) is an asymptomatic cerebrovascular disorder. The aim of the present study was to investigate the association between adrenoceptor-α2 (ADRA2) gene polymorphisms and SBI. A total of 361 patients with SBI and 467 healthy control subjects were examined. The polymerase chain reaction was performed to genotype the ADRA2A 1780G>A, ADRA2B 301-303 insertion/deletion (I/D) and ADRA2C 322-325I/D polymorphisms. The frequency of the ADRA2C 322-325I/D polymorphism was significantly different between patients with SBI and control subjects. When interaction analyses were performed for vascular risk factors, the ADRA2C 322-325ID genotype increased the risk for SBI in the presence of hypertension and elevated plasma homocysteine levels. The ADRA2C 322-325ID genotype and plasma homocysteine levels showed a significant synergistic effect for SBI. In addition, the ADRA2A 1780AA genotype was associated with elevated plasma homocysteine levels. Although further analysis of the association between ADRA2 polymorphisms and clinical risk factors of SBI is required, the present study of a limited set of SBI risk factors with ADRA2 polymorphisms provides the first evidence of the involvement of ADRA2 gene family members in the development of SBI. Further studies using larger and more heterogeneous populations are required to validate the association of ADRA2 polymorphisms with SBI.

LA volumes and reservoir function are associated with subclinical cerebrovascular disease: the CABL (Cardiovascular Abnormalities and Brain Lesions) study

OBJECTIVES

The purpose of this study was to assess the relationship of left atrial (LA) phasic volumes and LA reservoir function with subclinical cerebrovascular disease in a stroke-free community-based cohort.

BACKGROUND

An increase in LA size is associated with cardiovascular events including stroke. However, it is not known whether LA phasic volumes and reservoir function are associated with subclinical cerebrovascular disease.

METHODS

The LA minimum (LAV(min)) and maximum (LAV(max)) volumes, and LA reservoir function, measured as total emptying volume (LAEV) and total emptying fraction (LAEF), were assessed by real-time 3-dimensional echocardiography in 455 stroke-free participants from the community-based CABL (Cardiovascular Abnormalities and Brain Lesions) study. Subclinical cerebrovascular disease was assessed as silent brain infarcts (SBI) and white matter hyperintensity volume (WMHV) by brain magnetic resonance imaging.

RESULTS

Prevalence of SBI was 15.4%; mean WMHV was 0.66 ± 0.92%. Participants with SBI showed greater LAV(min) (17.1 ± 9.3 ml/m(2) vs. 12.5 ± 5.6 ml/m(2), p < 0.01) and LAV(max) (26.6 ± 8.8 ml/m(2) vs. 23.3 ± 7.0 ml/m(2), p < 0.01) compared to those without SBI. The LAEV (9.5 ± 3.4 ml/m(2) vs. 10.8 ± 3.9 ml/m(2), p < 0.01) and LAEF (38.7 ± 14.7% vs. 47.0 ± 11.9%, p < 0.01) were also reduced in participants with SBI. In univariate analyses, greater LA volumes and smaller reservoir function were significantly associated with greater WMHV. In multivariate analyses, LAV(min) remained significantly associated with SBI (adjusted odds ratio per SD increase: 1.37, 95% confidence interval: 1.04 to 1.80, p < 0.05) and with WMHV (β = 0.12, p < 0.01), whereas LAVmax was not independently associated with either. Smaller LAEF was independently associated with SBI (adjusted odds ratio: 0.67, 95% confidence interval: 0.50 to 0.90, p < 0.01) and WMHV (β = -0.09, p < 0.05).

CONCLUSIONS

Greater LA volumes and reduced LA reservoir function are associated with subclinical cerebrovascular disease detected by brain magnetic resonance imaging in subjects without history of stroke. In particular, LAV(min) and LAEF are more strongly associated with SBI and WMHV than the more commonly measured LAVmax, and their relationship with subclinical brain lesions is independent of other cardiovascular risk factors.

Prevalence of unrecognized myocardial infarction detected with magnetic resonance imaging and its relationship to cerebral ischemic lesions in both sexes

OBJECTIVES

The purpose of this study was to investigate the prevalence of unrecognized myocardial infarction (UMI) detected with magnetic resonance imaging (MRI) and whether it is related to cerebral ischemic lesions on MRI in an elderly population-based cohort.

BACKGROUND

There is a correlation between stroke and recognized myocardial infarction (RMI) and between stroke and UMI detected with electrocardiography, whereas the prevalence of stroke in subjects with MRI-detected UMI is unknown.

METHODS

Cerebral MRI and cardiac late-enhancement MRI were performed on 394 randomly selected 75-year-old subjects (188 women, 206 men). Images were assessed for cerebral ischemic lesions and myocardial infarction (MI) scars. Medical records were scrutinized. Subjects with MI scars, with or without a hospital diagnosis of MI, were classified as RMI or UMI, respectively.

RESULTS

UMIs were found in 120 subjects (30%) and RMIs in 21 (5%). The prevalence of UMIs (p = 0.004) and RMIs (p = 0.02) was greater in men than in women. Men with RMI displayed an increased prevalence of cortical and lacunar cerebral infarctions, whereas women with UMI more frequently had cortical cerebral infarctions (p = 0.003).

CONCLUSIONS

MI scars are more frequent in men than in women at 75 years of age. The prevalence of RMI is related to that of cerebral infarctions.

Risk of "silent stroke" in patients older than 60 years: risk assessment and clinical perspectives

With the increasing size of the elderly population and evolving imaging technology, silent brain infarction (SBI) has garnered attention from both the public and the physicians. Over 20% of the elderly exhibit SBI, and the prevalence of SBI increases steadily with age, ie, 30%–40% in those older than 70 years. Well-known cardiovascular risk factors such as hypertension has been identified as a risk factor of SBI (odds ratio [OR] = 3.47) Besides this, blood pressure (BP) reactivity to mental stress, morning BP surges, and orthostatic BP changes have been demonstrated to contribute to the presence of SBI. Further, a metabolic syndrome not only as a whole syndrome (OR =2.18) but also as individual components could have an influence on SBI. Increased C-reactive protein and interleukin-6, coronary artery disease, body mass index, and alcohol consumption have also been associated with SBI. The ORs and possible mechanisms have been discussed in this article. Overt stroke, dementia, depression, and aspiration pneumonia were all associated with SBI. (overt stroke: hazard ratio [HR] =1.9, 95% confidence interval [CI]: 1.2–2.8; dementia: HR =2.26, 95% CI: 1.09–4.70). We also looked into their close relationship with SBI in this review.

Sex differences in the risk profile and male predominance in silent brain infarction in community-dwelling elderly subjects: the Sefuri brain MRI study

Although brain infarction is more common in men, the male predominance of silent brain infarction (SBI) was inconsistent in the earlier studies. This study was to examine the relationship between sex differences in the risk profile and SBI. We conducted a population-based, cross-sectional analysis of cardiovascular risk factors and SBI on MRI. We asked all the female participants about the age at natural menopause and parity. SBI was detected in 77 (11.3%) of 680 participants (266 men and 414 women) with a mean age of 64.5 (range 40-93) years. In the logistic analysis, age (odds ratio (OR)=2.760/10 years, 95% confidence interval (CI)=2.037-3.738), hypertension (OR=3.465, 95% CI=1.991-6.031), alcohol intake (OR=2.494, 95% CI=1.392-4.466) and smoking (OR=2.302, 95% CI=1.161-4.565) were significant factors concerning SBI. Although SBI was more prevalent among men, this sex difference disappeared on the multivariate model after adjustment for other confounders. In 215 women aged 60 years or older, age at natural menopause, early menopause, duration of menopause, number of children and age at the last parity were not significantly associated with SBI after adjustment for age. Hypertension and age were considered to be the major risk factors for SBI in community-dwelling people. Male predominance in SBI was largely due to higher prevalence of alcohol habit and smoking in men than in women in our population.

Monocyte count is an underlying marker of lacunar subtype of hypertensive small vessel disease

BACKGROUND

In the hypertensive small vessel disease (HSVD), it remains unclear why some patients develop lacunar infarcts (LIs) whilst others develop deep intracerebral hemorrhages (dICHs). Inflammation might be related to LI, and leukocyte and monocyte counts are regarded as an inflammatory marker of ischemic stroke.

OBJECTIVE

We investigated the relationship between leukocyte and monocyte counts determined in the first 24 h after stroke onset in HSVD patients.

METHODS

We prospectively studied 236 patients with first acute stroke because of HSVD (129 LI and 107 dICH). We analyzed demographic data, vascular risk factors, and white blood cell count subtypes obtained in the first 24 h after stroke.

RESULTS

The multivariate analysis showed that LI subtype of HSVD was correlated with hyperlipidemia (P < 0.0001), a higher monocyte count (P = 0.002), and showed a trend with current smoking (P = 0.051), whereas dICH subtype was correlated with low serum total cholesterol (P = 0.003), low serum triglycerides (P < 0.0001), and high neutrophil count (P = 0.050).

CONCLUSIONS

In patients who developed HSVD-related stroke, high monocyte count, current smoking, and hyperlipidemia are prothrombotic factors related to LI, whereas low cholesterol and triglyceride values are related to dICH. Monocyte count might be an inflammatory risk marker for the occlusion of small vessels in hypertensive patients.

Prevalence, awareness, treatment, and control of hypertension in rural adults from Liaoning Province, northeast China

Liaoning Province is located in northeast China, which has distinct weather conditions, geographic characteristics and lifestyles compared with other regions of the country; the lifestyle differences are especially pronounced in the rural parts of this region, where there is a dearth of financial and other resources. However, information on the prevalence, awareness, treatment, and control of hypertension in these impoverished areas is very scarce. We therefore performed multistage cluster random sampling of a group of 29,970 adult residents (>or=5 years of residency; >or=35 years of age) of the rural portions of Liaoning Province from 2005 to 2006. The sampling included a survey on blood pressure and associated risk factors. The overall prevalence of hypertension in the community was 36.2%, and 73.0% of hypertensives were unaware of their condition. Among the total group of hypertensives, only 19.8% were taking prescribed medication to lower their BP, and 0.9% had controlled hypertension. Of all subjects, 46.4% did not think that high blood pressure would endanger their lives. As to the reasons given by hypertensives who were aware of their hypertension for not taking antihypertensive medication, 47.4% reported that they lacked knowledge about the mortality of hypertension. The average salt intake in hypertensives was 16.6+/-9.9 g/day, and the percentages of smoking (44.3%), drinking (31.7%) and salt intake>6 g/day (86.8%) in hypertensives were high. Logistic regression analysis indicated that the relative risks (95% confidence interval [CI]) of overweight, obesity, smoking, drinking, increased salt intake and family history of hypertension for hypertension were 1.95 (range, 1.82-2.08), 2.92 (2.40-3.55), 1.19 (1.12-1.27), 1.16 (1.08-1.25), 1.26 (1.20-1.33) and 2.85 (2.66-3.05), respectively. A higher education level was found to be a protective factor. In conclusion, the prevalence of hypertension in adults living in the rural parts of Liaoning Province was high, and the rates of awareness, treatment, and control were unacceptably low, which may have been due to unique geographical characteristics, unwholesome lifestyles, greater sodium intake, lower education levels, and genetic risk factors.

Influence of hypertension on the incidence of cardiovascular disease in two rural communities in Japan: the Tanno-Sobetsu [corrected] study

The purpose of this study was to determine the relationship between hypertension and onset of cardiovascular disease in Japan. As part of an ongoing epidemiological survey of cardiovascular diseases in Hokkaido, Japan, 1,798 subjects (806 males and 992 females; mean age in the initial year of the survey, 58.6+/-11.8 years) were selected, after excluding subjects who had been taking antihypertensive drugs, from a total of 2,136 subjects who had undergone medical examinations in 1991 in the town of Tanno and in 1992 in the town of Sobetsu, two rural communities in Hokkaido. Height, weight, casual systolic and diastolic blood pressures in the sitting position and blood biochemical values of all subjects were measured, and the subjects were divided into blood pressure level groups according to the 1999 World Health Organization/International Society of Hypertension (WHO/ISH) criteria. The follow-up survey was concluded at the end of August in 1999. The endpoints in this study were onset of circulatory disease or death due to circulatory disease. During the follow-up period, circulatory diseases (ischemic heart disease or stroke) occurred in 94 of the subjects. The incidence rates of cardiovascular disease (per 1,000 persons/year) for subjects divided into blood pressure groups according to the 1999 WHO/ISH blood pressure classification were 6.24 for the optimal+normal blood pressure level group, 11.26 for the normal high blood pressure level group, and 15.83 for the grade 1-3 hypertension group. Thus, the incidence rate of circulatory disease increased as the blood pressure level increased, and there was a significant difference between the incidence rate in subjects in the grade 1-3 hypertension group and the incidence rate in subjects in the optimal+normal blood pressure level group (p<0.05). In a Cox's proportional hazards model with onset of circulatory disease as the endpoint, diastolic blood pressure was shown to be an independent risk factor with a relative risk of 1.01. The results suggest that hypertension is an independent risk factor for onset of circulatory disease.

Silent brain infarcts: a systematic review

As the availability and quality of imaging techniques improve, doctors are identifying more patients with no history of transient ischaemic attack or stroke in whom imaging shows brain infarcts. Until recently, little was known about the relevance of these lesions. In this systematic review, we give an overview of the frequency, causes, and consequences of MRI-defined silent brain infarcts, which are detected in 20% of healthy elderly people and up to 50% of patients in selected series. Most infarcts are lacunes, of which hypertensive small-vessel disease is thought to be the main cause. Although silent infarcts, by definition, lack clinically overt stroke-like symptoms, they are associated with subtle deficits in physical and cognitive function that commonly go unnoticed. Moreover, the presence of silent infarcts more than doubles the risk of subsequent stroke and dementia. Future studies will have to show whether screening and treating high-risk patients can effectively reduce the risk of further infarcts, stroke, and dementia.

Extracranial carotid plaque is increasing in Japanese ischemic stroke patients

OBJECTIVE

The objectives of this study were to investigate the prevalence of extracranial carotid plaque and the association between risk factors and carotid plaque in Japanese patients with ischemic stroke.

METHODS

We consecutively recruited patients with ischemic stroke admitted to our hospital from January 2000 to September 2002. Neurologic signs and a brain magnetic resonance imaging diagnosed ischemic stroke. All subjects underwent a carotid ultrasonography. Multiple logistic regression analysis was used to determine the risk factors that independently contributed to the presence of carotid plaques.

RESULTS

Carotid plaques were identified in 76.2% of the patients and bilateral plaques were found in 58.2%. These lesions were more frequent in comparison with previous Japanese reports. The risk factors that independently contributed to the presence of extracranial carotid plaques were hypertension, age, smoking and past history of ischemic stroke.

CONCLUSIONS

This study demonstrates that extracranial carotid plaque is increasing in Japanese patients with ischemic stroke.

Cognitive impairment in elderly women: the relative importance of selected genes, lifestyle factors, and comorbidities

BACKGROUND

A variety of factors contribute to the development of cognitive impairment in elderly people. Previous studies have focused upon a single or a few risk factors. In this study we assessed and compared the significance of a wide variety of potential risk factors for cognitive impairment in postmenopausal women.

METHODS

A total of 208 pairs of elderly women (mean age = 73.2 years) were examined in a cross-sectional case-control study. Each pair consisted of a case (with impaired cognition) and a control subject matched by age and educational status. Cognitive functions were determined using a modified version of the Blessed test. Participants were also subjected to a general clinical examination and they were interviewed to collect information on lifestyle practices and comorbid disorders. Genotypes for the apolipoprotein E (APOE) epsilon4, catechol-O-methyltransferase (COMT) Val/Met, and brain-derived neurotropic growth factor (BDNF) Val/Met polymorphisms were determined. Data were analyzed by conditional logistic regression.

RESULTS

We identified a set of risk factors for age-related cognitive impairment. A statistical model for assessment of the importance of these factors was constructed. The factors in this model were physical exercise (odds ratio [OR] = 0.50, 95% confidence interval [CI] = 0.32-0.78), regular alcohol consumption (OR = 0.49, 95% CI = 0.29-0.83), metabolic syndrome (OR = 2.83, 95% CI = 1.26-6.39), depression (OR = 3.24, 95% CI = 1.28-8.22), and the APOE epsilon4 allele (OR = 1.76, 95% CI = 1.09-2.83). Also COMT genotype was present as a risk factor in the statistical model (p = 0.08).

CONCLUSIONS

Lifestyle risk factors, comorbid disorders, and genetic factors contribute to development of age-related cognitive impairment. The two former groups of risk factors appear to be particular important in this respect.

Association between carotid hemodynamics and asymptomatic white and gray matter lesions in patients with essential hypertension

The aim of this study was to clarify the magnitude of common carotid artery (CCA) structural and hemodynamic parameters on brain white and gray matter lesions in patients with essential hypertension (EHT). The study subjects were 49 EHT patients without a history of previous myocardial infarction, atrial fibrillation, diabetes mellitus, impaired glucose tolerance, chronic renal failure, symptomatic cerebrovascular events, or asymptomatic carotid artery stenosis. All patients underwent brain MRI and ultrasound imaging of the CCA. MRI findings were evaluated by periventricular hyperintensity (PVH), deep and subcortical white matter hyperintensity (DSWMH), and état criblé according to the Japanese Brain dock Guidelines of 2003. Intima media thickness (IMT), and mean diastolic (Vd) and systolic (Vs) velocities were evaluated by carotid ultrasound. The Vd/Vs ratio was further calculated as a relative diastolic flow velocity. The mean IMT and max IMT were positively associated with PVH, DSWMH, and état criblé (mean IMT: rho=0.473, 0.465, 0.494, p=0.0007, 0.0014, 0.0008, respectively; max IMT: rho=0.558, 0.443, 0.514, p=0.0001, 0.0024, 0.0004, respectively). Vd/Vs was negatively associated with état criblé (rho=-0.418, p=0.0038). Carotid structure and hemodynamics are potentially related to asymptomatic lesions in the cerebrum, and might be predictors of future cerebral vascular events in patients with EHT.

Smoking and antihypertensive medication: interaction between blood pressure reduction and arterial stiffness

To investigate how cigarette smoking and antihypertensive drug therapy may interact to affect cardiovascular disease, in this prospective study we administered amlodipine to hypertensive smokers and non-smokers and compared blood pressure reduction and indices of arterial stiffness. We measured blood pressure (BP), heart rate (HR), brachial-ankle pulse wave velocity (baPWV), and the carotid augmentation index (AIx) by using a non-invasive automated device in 101 hypertensive patients at baseline and at 1, 3, and 6 months of amlodipine administration (5.0 mg). At baseline, the AIx was significantly lower in smokers (n=27) than in non-smokers (n=74) (27.3% +/- 13.3% vs. 33.3% +/- 11.4%). After amlodipine administration, in both the groups, the mean BP, baPWV, and AIx were significantly reduced; however, the HR did not show a statistically significant difference. The reduction in the baPWV (cm/s) at 1 and 3 months was less marked in smokers than in non-smokers (mean +/- SD: -186.6 +/- 36.5 vs. -283.6 +/- 24.5 at 1 month; -136.6 +/- 42.2 vs. -280.1 +/- 29.6 at 3 months, respectively, both p<0.05). At 6 months, these intergroup differences in the reductions of baPWV disappeared. The blunted reduction of baPWV, particularly at 3 months, was significantly associated with the extent of smoking (lifetime pack-years smoked). Changes observed in the AIx and mean BP were similar between groups throughout the study period. In the short term, cigarette smoking blunts the effect of amlodipine on the reduction of arterial stiffness, independently of the mean BP level.

Prevalence, Awareness, Treatment, Control and Risk Factors of Hypertension in the Guangxi Hei Yi Zhuang and Han Populations

Han is the largest nationality and Zhuang is the largest minority among the 56 nationalities in China. Geographically and linguistically, Zhuang can be classified into 43 ethnic subgroups, with the Hei Yi Zhuang Chinese, who live in Napo County bordering northeast Vietnam and comprise a population of 51,655, having the most conservative culture and customs (Hei Yi means "black-clothing" and the Hei Yi Zhuang revere and wear the color black). The determinants of hypertension and its risk factors in this population have not been well-defined. To obtain some of this information, a cross-sectional study of hypertension was carried out in 1,166 Hei Yi Zhuang Chinese (aged 7-84; mean, 44.00+/-17.54 years) and 1,018 Han Chinese controls (42.95+/-17.11; range, 6-89 years) in the same area. Information on demographic characteristics, health-related behaviors and lifestyle factors was collected by questionnaire. The overall prevalence rates of hypertension and isolated systolic hypertension in Hei Yi Zhuang were higher than those in Han (23.2% vs. 16.0% and 11.5% vs. 3.7%; p<0.001 for each). The levels of systolic blood pressure and pulse pressure in Hei Yi Zhuang were also higher than those in Han (p<0.001 for each). The prevalence of hypertension was positively correlated with triglycerides, male gender, and age in Hei Yi Zhuang, whereas it was positively correlated with total cholesterol, male gender, age, and alcohol consumption in Han. The rates of awareness, treatment and control in Hei Yi Zhuang were lower than those in Han (8.5% vs. 20.9%, 4.4% vs. 15.3%, and 1.9% vs. 10.4%; p<0.001 for each), which may have been due to unique geographical characteristics, unwholesome lifestyles, greater sodium intake, lower education levels, and genetic risk factors in the former group.

Low-Density Lipoprotein Subfractions and the Prevalence of Silent Lacunar Infarction in Subjects with Essential Hypertension

Recent lipid research has focused on low-density lipoprotein (LDL) subfractions as new markers for cardiovascular risk. However, the clinical significance of measurement of LDL subfractions in subjects with essential hypertension is yet to be established. We studied the association between the prevalence of silent lacunar infarction (SLI) and LDL subfractions in patients with essential hypertension. We performed brain MRI to detect SLI and measured LDL subfractions in 100 asymptomatic non-diabetic middle-aged subjects with essential hypertension (mean age, 62 years). We fractionated LDL into three parts, LDL-1, LDL-2, and LDL-3, with LDL-3 being the oxidized subfraction. Of the 100 study subjects, 24 (24%) had one or more SLIs, while the remaining 76 (76%) were considered as a non-SLI group. The LDL-3 levels were significantly higher in the SLI group than in the non-SLI group (8.3 +/- 4.4 mg/dl vs. 6.3 +/- 2.0 mg/dl, p = 0.006). Multiple logistic regression analysis showed that LDL-3 levels alone were an independent predictor of SLI (odds ratio [OR]: 1.380; 95% confidence interval [CI]: 1.113-1.663; p = 0.003). When subjects were divided into quartiles based on LDL-3 levels, the prevalence of SLI was significantly higher in the highest LDL-3 level group than in the lowest LDL-3 level group (p = 0.0036). The present study suggests that LDL-3 levels are associated with the prevalence of SLI in subjects with essential hypertension.

Comparison of brachial-ankle pulse wave velocity in Japanese and Russians

Pulse wave velocity (PWV) is a well-known indicator of arterial stiffness and a marker of the presence of vascular lesions. Cardiovascular mortality in Russia has become the highest in the world. The Japanese are enjoying long lives, and the mortality caused by cardiovascular diseases has thus far remained at lower levels than that in Russia. In this study, we focused on brachial-ankle pulse wave velocity (baPWV) obtained from normal human subjects in Russia as well as in Japan, and compared their respective cardiovascular risks. We evaluated baPWV in 337 Japanese and 138 Russian healthy subjects. The baPWV was recorded using a PWV diagnosis device. BaPWV was measured between 2 locations of the arterial tree. The baPWV in the Russian group was significantly higher than that obtained in the Japanese of two groups categorized by age (40-59 years and 60- years). Further, body mass index (BMI), systolic blood pressure (SBP) and diastolic blood pressure in the Russian group were significantly higher than those obtained in Japanese in three age groups (under 39 years, 40-59 years, and 60- years). Moreover, the baPWV indicated a positive correlation with age, BMI and SBP in both Japanese and Russians, although the increasing trend of the baPWV against age of the Russian group had a larger value than that of the Japanese. Therefore, we suggest that arterial stiffness might be promoted earlier in the Russian group, which might be the main cause of the increased cardiovascular risk in Russia.

A Case of Vertebral Artery Dissection Associated with Morning Blood Pressure Surge

We report a case of a middle-aged man who suffered a cerebral infarction resulting from dissection of a vertebral artery associated with morning blood pressure surge. A 56-year-old man was transferred to our hospital with dizziness and vomiting in the early morning on a cold day in winter. He reported that he had been standing in front of the sink after bathing when he suddenly felt dizzy and fell down. He did not lose consciousness, and by the time he reached the hospital by ambulance, his dizziness had subsided, but he complained of severe headache and vomited 3 times. On admission, he was alert, and there were no neurological or radiological abnormalities (CT, MR angiography) in the brain. However, infarction in the left cerebellar hemisphere was detected by brain MRI on the 5th day of hospitalization. String sign of the left vertebral artery was noted by angiography, confirming the diagnosis of dissection of the left vertebral artery. Ambulatory blood pressure monitoring was performed after discharge. Although the mean 24-h blood pressure was in the normal range, a marked morning blood pressure rise was observed. We speculated that the acute rise of blood pressure in the early morning might have contributed to the dissection of the vertebral artery.

Effects of Microbleeds on Hemorrhage Development in Leukoaraiosis Patients

The possible influences of cerebral microbleeds (CMBs) on the development of intracerebral hemorrhage (ICH) in patients with leukoaraiosis (LA) have rarely been examined. We aimed to determine whether CMBs might be a risk factor for ICH in hypertensive patients with leukoaraiosis. We studied 70 hypertensive patients with acute ICH and LA (the ICH group) by brain MRI, including T2*-weighted gradient-echo sequences. The control group was composed of 73 hypertensive LA patients without ICH. CMBs and old lacunae were counted in the group of patients with ICH and in the control subjects and compared. The ICH group contained more patients with CMBs (68 patients; control group, 41; p < 0.01), and showed a higher mean number of lesions (19.9 +/- 31.1; control group, 7.4 +/- 19.6; p < 0.01). The negative predictive value for ICH was highest among the ICH patients without CMB (94.1%), and the positive predictive value was highest among the ICH patients with 6 or more CMBs (75.4%). Old lacunae were observed more frequently in the ICH group (65 patients; control group, 58; p = 0.02), but their predictive value for ICH was not high (positive, 52.3%; negative, 75.0%). Our results indicated that CMBs may be used to predict the risk of ICH in hypertensive patients with advanced LA.