Stroke units in Italy: engaging the public in optimizing existing resources.

BACKGROUND AND PURPOSE: The lack of a wide implementation of stroke units (SU)s in Italy appears to accompany the underuse of the operating units. Community awareness of acute stroke care options may affect stroke resource use. Our aim was to determine the level of knowledge about SUs and tissue-plasminogen activator (t-PA) treatment amongst Italian adults and investigate its relationship to local stroke services implementation. METHODS: A nation-based telephone survey was carried out in a sample of 1000 residents aged >18 years in May-June 2010. The questionnaire included close-ended questions regarding knowledge of SUs and t-PA treatment. Number and location of both SUs and t-PA treatments were provided by a concurrent national hospital-based survey. The prevalence and distribution of acute stroke care awareness in the community was examined and multivariate analyses were generated. RESULTS: Amongst the 1000 participants (474 men, mean age 48.8 ± 17.2), only 26.2% reported knowing about the availability of t-PA treatment and only 15% were aware of the existence of SUs. Awareness of both SUs and t-PA was significantly associated only with education. These associations remained significant in the multivariate analyses. The degree of stroke services implementation (in terms of SUs/inhabitant rates and number of t-PA treatments) was not associated with SU and t-PA awareness. CONCLUSIONS: This is the first European study that explored public knowledge about t-PA treatment and SUs. Italian adults proved insufficiently educated about SUs and t-PA; there is no higher awareness in areas with a greater supply of stroke services. This might partially explain the underuse of Italian SUs.

Post-stroke rehabilitation in Italy: inconsistencies across regional strategies.

BACKGROUND: Remarkable differences among European countries have been found in stroke rehabilitation models, owing to the fact that stroke rehabilitation services are embedded in health care systems. Comprehensive data on service utilization by stroke survivors in Italy are lacking, but would be instrumental in improving efficiency and effectiveness of post-acute stroke care, and consequently, in containing costs and improving outcomes. AIM: The purpose of the present study was to survey the Italian regional legislations in order to examine the provision of rehabilitation services for stroke survivors in Italy. DESIGN: This is a cross-sectional, observational study. SETTING: Post-stroke intra- and extra-hospital rehabilitation. POPULATION: All decrees and resolutions as to post-acute stroke rehabilitation were collected from each Italian region. METHOD: All decrees and resolutions were examined by the means of a check list including quantitative and qualitative characteristics, selected in accordance with national official recommendations. Each completed check list was then sent to each regional reference person, who filled in the section on the implementation of the indications and compliance. RESULTS: The study was carried out from November 2009 to September 2010. The documents were collected from 19 out of the 20 Italian regions. The results of the study indicate that there are many, remarkable regional variations in health policies concerning post-stroke care. Instruments for evaluation and criteria for allocating stroke patients to proper rehabilitation setting vary across regions, but data on the potential impact of these variations on clinical outcomes are still lacking. CONCLUSION: The study highlights the issue that, in Italy, delivery of post-stroke rehabilitation services is not uniform nation-wide and varies substantially across regions. The lack of a comprehensive post-acute stroke strategy is a major obstacle to service availability. CLINICAL REHABILITATION IMPACT: The study results advocate the need for a consistent and comprehensive strategic planning of post-stroke rehabilitation in Italy.

Effectiveness of public stroke educational interventions: a review.

BACKGROUND AND PURPOSE: Recognizing stroke symptoms and acting quickly can reduce death and disability, but public awareness of stroke risk factors, symptoms and what to do about them is still limited. Stroke educational campaigns are used worldwide but there are few published evaluations of such campaigns. METHODS: The literature from 1999 to 2012 on the effectiveness of stroke educational campaigns was reviewed and summarized with narrative synthesis. Web-based campaigns were also described. Three databases and one search engine were explored with two keywords (stroke campaign and stroke promotion). The reference lists of all included articles were also examined. RESULTS: Twenty-two intervention studies and five web-based campaigns were included in the review. Most interventions proved partially effective, in terms of gender preference (women) or type of information retained or media preferred. Only one intervention proved ineffective. Mass media campaigns can be effective but require sustained funding, and their ability to target high-risk subgroups, whether aging, linguistic or socioeconomic, is unclear. Three community-based participatory stroke promotion interventions proved partially effective, but the small sample sizes might have underpowered the results. Web-based campaigns are efficient in reaching a large number of people but tend to attract a selected and self-selected population. CONCLUSIONS: Stroke educational campaigns have the potential to improve knowledge and awareness and change the behavior of a large number of people. Health promoters and investigators must adopt flexibility and participatory mentality to develop cost-effective interventions. Both community-based campaigns and E-tools should be integrated within a comprehensive multifaceted stroke promotion strategy to expand their reach.

Updating on Italian stroke units: the "CCM study".

The stroke units (SUs) have been demonstrated to be efficient and cost effective for acute stroke care. Nevertheless, the level of stroke unit implementation in Italy does not correspond to expectations yet. This study is a survey, which aims at assessing the current status of in-hospital stroke care in the Italian regions and at updating SUs. The survey was conducted by means of a semi-structured questionnaire, based on 18 stroke care "quality indicators", submitted to all the Italian centres that had taken part in the SITS-MOST study, and to other centres advised by the coordinator of SITS studies and by regional opinion leaders of stroke. SUs were defined as acute wards, with stroke-dedicated beds and dedicated teams that had been formally authorised to administer rt-PA. A statistical analysis was performed by a descriptive statistics and logistic regression model. The study was carried out from November 2009 to September 2010. A total of 168 forms were sent out and 153 replies received. Seven centres, which had not performed any thrombolytic treatment, and 16 which did not fulfil the criteria for the definition of SU were excluded from the study. Most of the centres reported more than 100 stroke patient admissions per year, i.e., 122 (84%) from 100 to 500, 18 (12%) more than 500. The 19% of the centres admitted more than 30% of patients within 3 h from the symptom onset and only 30% admitted more than 30% of patients within 4.5 h. The mean number of thrombolyses performed in the last 6 months was 10 for centres with a doctor on duty 24 h a day, 6 for those that have a doctor on duty from 8 a.m. to 8 p.m. and a doctor on call for night, and 5 for centres with a doctor on call 24 h a day. The territorial distribution of the SUs is remarkably heterogeneous: 87 SUs (67%) are located in the North of Italy, 28 (22%) in the central part of Italy and only 15 (11%) in the South. The last few years have witnessed a rise in both the diffusion of SUs and access to thrombolytic therapy in Italy. Despite this, there are a few large areas, mostly in the south, where the requirements of healthcare legislation are not met, and access to a dedicated SU and thrombolytic treatment is still limited and poor.

The impact of fine-tuning of optical recognition system on database reliability.

Although optical reading systems are important tools to transfer data from a paper form to electronic databases, the impact of system fine-tuning on the final error rate is not usually considered. At the end of a multi-step process involving paper form design training of operators, and fine-tuning procedure, the final rate of error can be reduced from 0.65% to 0.05%. Fine-tuning should be introduced as a standard procedure while using optical reading systems.

Stroke unit care in clinical practice: an observational study in the Florence center of the European Registers of Stroke (EROS) Project.

BACKGROUND: Randomized trials and meta-analyses indicate positive effects of stroke unit (SU) care on survival and dependency of patients with stroke. However, data on the advantages of SU in 'real-world' settings are limited. We prospectively assessed, in a large University Hospital, the effect of SU versus other conventional wards (OCW) care on all-cause mortality, death or dependency, death or institutionalization. METHODS: In a prospective observational study in the European Registers of Stroke Project, patients hospitalized for first-in-a-lifetime stroke were evaluated for demographics, risk factors, clinical presentation, resource use, 3-month and 1-year survival, and functional outcome. RESULTS: Overall, 355 patients (54.1% men, mean age 73.4 ± 14.5 years) were registered, 140 (39.4%) admitted to the SU, and 215 (60.6%) to OCW. OCW patients were older, whilst SU patients had more severe strokes according to NIHSS (P for trend = 0.025). SU patients were significantly more often treated by specialists in stroke medicine, stroke nurses, physiotherapists and speech therapists (all P < 0.001), psychologists (P = 0.025), dietitians (P < 0.001), and social workers (P = 0.003). MRI, carotid, and transcranial Doppler were significantly more often performed in SU patients (all P < 0.001). Intravenous fluids (P = 0.003) and intravenous anticoagulation (P < 0.001) were more often prescribed in SU. Controlling for case-mix, SU significantly reduced 1-year mortality (P = 0.020), death or dependency at 3 months (P = 0.006) and 1 year (P = 0.043), and death or institutionalization at 3 months (P = 0.001) and 1 year (P = 0.009). CONCLUSIONS: We confirmed the benefits of SU care in a clinical setting. Further analyses should define the contribution of individual components of care to stroke outcome.

Subcortical ischaemic changes in young hypertensive patients: frequency, effect on cognitive performance and relationship with markers of endothelial and haemostatic activation.

Information on subcortical ischaemic changes (SIC) in young hypertensive patients is scarce. We evaluated the frequency of SIC at magnetic resonance imaging (MRI), the possible effect on cognition of these patients, and the role of plasma markers known as indicators of endothelial and haemostatic activation. Inclusion criteria were age

CIND and MCI in the Italian elderly: frequency, vascular risk factors, progression to dementia.

OBJECTIVE: To estimate prevalence and progression to dementia of cognitive impairment, no dementia (CIND), mild cognitive impairment (MCI), and relative subtypes, evaluating the relationships with daily functioning, cardiovascular diseases and vascular risk factors. METHODS: We evaluated CIND and MCI in the Italian Longitudinal Study on Aging. The neuropsychological battery assessed global cognitive function, memory and attention. Two thousand eight hundred thirty participants were examined at baseline and after a mean follow-up of 3.9 +/- 0.7 years. RESULTS: The prevalence was 9.5% for CIND and 16.1% for MCI. Prevalence rates for CIND subtypes were 1.8% for amnestic, 2.3% for single nonmemory, 1.5% for multidomain, and 3.9% for CIND defined only on global cognitive function. The prevalence was 7.0% for amnestic, 7.8% for single nonmemory, and 1.3% for multidomain MCI. Incidence of dementia (per 1,000 person-years) was 7.63 in the total sample, 21.37 in CIND, and 13.59 in MCI. In MCI, rates ranged from 8.74 in amnestic to 40.60 in multidomain subtype. The highest incidence of 56.02 per 1,000 person-years was found in multidomain CIND. Both CIND and MCI increased by almost three times the risk of dementia at follow-up. Among baseline variables, only previous stroke and impairment in instrumental activities of daily living significantly increased the risk of dementia at follow-up. CONCLUSIONS: Both cognitive impairment, no dementia and mild cognitive impairment are frequent in the Italian elderly (2,955,000 prevalent cases expected) and significantly predict progression to dementia. Individuation of subgroups with different risk factors and transition rates to dementia is required to plan early and cost-effective interventions.

Epidemiology of distal symmetrical neuropathies in the Italian elderly.

OBJECTIVES: To estimate prevalence and incidence of distal symmetric neuropathies (DSN) in the Italian elderly, and to evaluate the accuracy of our procedure to screen for DSN. METHODS: In eight Italian municipalities, a population-based sample was directly evaluated both at baseline (1992) and after a 3-year follow-up. Cohort members who had died were studied. DSN diagnosis and subtyping were made according to specified diagnostic criteria. RESULTS: Our screening procedure proved accurate (sensitivity 94.7%, specificity 70%, positive predictive value 18.9%), and provided an adjusted prevalence of 7.0 (95% CI, 6.9 to 7.0). Women outnumber men both in the oldest age groups and as a whole. Rates increase with increasing age in both genders. Among the 2,845 individuals re-screened at the follow-up and the 221 deceased subjects with reliable information, we identified 100 incident cases of DSN. Adjusted annual incidence rate (per 1,000 person-years) in the population 65 to 84 years of age is 7.9 (95% CI, 6.3 to 9.5), and for the nondiabetic DSN is 5.76 (95% CI, 4.3 to 7.3). Age significantly predicted the onset of DSN both in diabetic individuals (for every increasing year of age RR = 1.07; 95% CI, 1.01 to 1.14) and in the entire study population (RR = 1.05; 95% CI, 1.02 to 1.09). CONCLUSIONS: We provide the first population-based distal symmetric neuropathies incidence data, as well as prevalence rates from an unselected sample of Italian elderly. Distal symmetric neuropathies are an age-associated condition, but the frequency of diabetic distal symmetric neuropathies declines with age, coincident with an increase in nondiabetic cases.

Lifestyle-related risk factors for Parkinson's disease: a population-based study.

OBJECTIVES: To investigate the association of major lifestyle-related risk factors with the prevalent cases of Parkinson's disease (PD) identified by the Italian Longitudinal Study on Aging. METHODS: A total of 5632 individuals randomly selected from the population registers of eight centers were screened for parkinsonism using both a questionnaire and a neurologic examination. Screened positives underwent a structured clinical work-up for the diagnosis of parkinsonism and parkinsonism subtypes. RESULTS: We identified 113 prevalent cases of PD. Age, male gender, and pesticide-use license were significantly related to PD. Heavy smoking was inversely related to PD. Age (OR = 1.1; 95% CI, 1.06-1.15) and pesticide-use license (OR = 3.7; 95% CI, 1.6-8.6) kept their significant correlation with the disease in the multivariate analysis to adjust for all the variables under investigation. Multivariate analyses were made for men and women separately: pesticide exposure was positively associated with PD only in men. CONCLUSIONS: Pesticide exposure might represent a candidate for environmental factors involved in PD.

Dementia and disability: impact on mortality. The Italian Longitudinal Study on Aging.

Dementia is known to be associated with excess mortality. Physical disability, as a marker of dementia severity, is often considered the last step on the way from disease to death. The objective of this study was to investigate the direct effect of dementia on mortality in a population-based study, carried out in Italy, with a sample of 5,632 individuals aged 65-84 years. At 4-year follow-up, 998 participants had died. The independent predictors of death were: age (75-84 years; HR 2.63, CI = 2.11-3.27), male sex (HR 1.45, CI = 1.22-1.74), coronary heart disease (HR 1.61, CI = 1.34-1.94), moderate and severe instrumental activities of daily living disability (HR 1.98, CI = 1.30-3.03 and HR 3.26, CI = 2.09-5.09, respectively), diabetes in subjects with a survival time greater than 23 months (HR 0.68, CI = 0.43-1.08) and dementia (HR 2.07, CI = 1.62-2.66). These data provide evidence that dementia per se, independently from physical disability, is a strong predictor of death in the elderly.

High plasma insulin and lipids profile in older individuals: the Italian longitudinal study on aging.

BACKGROUND: The inverse relationship of insulin level to high-density lipoprotein (HDL)-cholesterol and its positive association with hypertriglyceridemia has been demonstrated in several studies; however, the relationship of insulin to low-density lipoprotein (LDL)-cholesterol in elderly persons is not clear. This study investigates the relationships of fasting plasma insulin and selected metabolic and biological risk factors in an aged population. METHODS: The present study is based on a cross-sectional analysis of the data collected at baseline of the Italian Longitudinal Study on Aging in 1992 on a random sample of 5632 Italians aged 65-84 years. Analyses were performed to compare the distribution of risk factors, such as blood level of lipids, creatinine, albumin, fibrinogen, apolipoprotein A-1 and B, blood pressure, and body mass index (BMI), by quartiles of insulin, in both diabetic and nondiabetic participants. RESULTS: Significantly higher levels of triglycerides and BMI and lower levels of HDL-cholesterol were found in the upper quartile of insulin among nondiabetic individuals. In men, we also found significantly higher levels of systolic and diastolic blood pressure. The same trend for these variables, although not significant for HDL-cholesterol and blood pressure, was seen in diabetic men. In diabetic women, total and LDL-cholesterol were significantly lower in the highest insulin quartile (p <.001), while no significant differences were seen in nondiabetic women or in men. We also found higher levels of white blood cells in the highest insulin quartile of diabetic women. CONCLUSIONS: These results, apparently in disagreement with earlier reports on the clustering of cardiovascular disease risk factors in hyperinsulinemic individuals, could be due to the high frequency of chronic inflammation and the high prevalence of urinary infections in older diabetic women.

Parkinson's disease, smoking, and family history. EUROPARKINSON Study Group.

There is growing evidence that both genetic and environmental factors play a role in the etiology of Parkinson's disease (PD). The hypothesis of an interaction between genetic and environmental risk factors has been little explored, and never using a population-based case-control study design. Our objective was to investigate the possible interaction between smoking and family history in the etiology of PD, as part of a collaborative population-based case-control study. We included 149 nondemented PD patients ascertained in three European prevalence surveys using a two-phase design. Each patient was matched by age (+/-2 years), gender, and center to three controls drawn from the same populations (n=375). Presence of PD among first-degree relatives and smoking history were assessed through an interview for 127 cases and 306 controls. In the overall sample we found suggestive evidence that family history and ever-smoking interact in determining the risk of PD (P=0.09), with individuals exposed to both risk factors having the highest risk (OR=10.0; 95% CI=2.0-49.6). Analyses were repeated after stratification into two age-groups (cutoff: 75 years). In older patients, the joint exposure to both risk factors was associated with a significant increase in the risk of PD (OR=17.6; 95% CI=1.9-160.5). Among younger subjects, the OR for joint exposure was not significant. In conclusion, our findings suggest that smoking and family history interact synergistically on a multiplicative scale in determining the risk of PD in individuals older than 75 years.

Parkinson's disease and parkinsonism in a longitudinal study: two-fold higher incidence in men. ILSA Working Group. Italian Longitudinal Study on Aging.

OBJECTIVE: To determine the incidence of parkinsonism and PD in the Italian elderly, and to explore the relation with age and gender. METHODS: In eight Italian municipalities, a population-based, parkinsonism-free cohort was followed for an average of 3 years. At the end of the follow-up, the cohort survivors were directly contacted (screening and clinical examination). Cohort members who had died were studied using death certificates, clinical records, and information gathered from relatives and general practitioners. Parkinsonism diagnosis and subtyping were made according to specified diagnostic criteria. RESULTS: The cohort consisted of 4,341 individuals (65 to 84 years of age): 596 died before the examination, 2,863 (76.4% of the survivors) completed the screening procedure, and 882 refused to participate. The authors found 68 incident cases of parkinsonism: 42 PD (62%), 7 drug-induced parkinsonism (10%), 8 parkinsonism in dementia (12%), 8 vascular parkinsonism (12%), and 3 parkinsonism, unspecified (5.8%). Average annual incidence rate (per 100,000 person-years) in the population aged 65 to 84 years, adjusted to the 1992 Italian population, was 529.7 (95% CI, 400.5 to 658.9) for parkinsonism, and 326.3 (95% CI, 224.1 to 427.5) for PD. Incidence rates for both parkinsonism and PD increased with age in both men and women; men had higher rates in every age group. Age-adjusted relative risk in men compared with women was 1.66 (95% CI, 1.02 to 2.70) for parkinsonism and 2.13 (95% CI, 1.11 to 4.11) for PD. CONCLUSIONS: Incidence of parkinsonism and PD increased with age, PD was the most common type of parkinsonism, and men had a risk of developing PD twice that of women.

Cognitive impairment without dementia in older people: prevalence, vascular risk factors, impact on disability. The Italian Longitudinal Study on Aging.

OBJECTIVES: To investigate prevalence of "cognitive impairment, no dementia" (CIND) in the Italian older population, evaluating the association with cardiovascular disease and the impact on activities of daily living (ADL). CIND may provide pathogenic clues to dementia and independently affect ADL. DESIGN: Cross-sectional examination in the context of the Italian Longitudinal Study on Aging. SETTING: Random population sample from eight Italian municipalities. PARTICIPANTS: A total of 3,425 individuals aged 65-84 years, residing in the community or institutionalized. MEASUREMENTS: Study participants were screened for cognitive impairment by using the Mini-Mental State Examination. Trained neurologists examined those scoring <24. CIND diagnosis relied on clinical and neuropsychological examination, informant interview, and assessment of functional activities. Age-related cognitive decline (ARCD) was diagnosed in CIND cases without neuropsychiatric disorders responsible for the cognitive impairment. RESULTS: Prevalence was 10.7% for CIND and 7.5% for ARCD, increased with age, and was higher in women. Age (odds ratio [OR], 1.09; 95% confidence interval [CI], 1.06-1.12), stroke (OR, 2.05; 95% CI, 1.26-3.35) and heart failure (OR, 1.73; 95% CI, 1.11-2.68) were significantly and positively associated with CIND at multivariate analysis. Education (OR, 0.61; 95% CI, 0.56-0.65) and smoking (OR, 0.72; 95% CI, 0.54-0.98) showed a negative correlation. Age and myocardial infarction were positively associated with ARCD, whereas a negative correlation was found for education and smoking. The effect of smoking was no more significant either on CIND or ARCD considering current habits or "pack year" exposure. CIND showed an independent impact on ADL (OR, 1.88; 95% CI, 1.41-2.49). CONCLUSIONS: CIND is very frequent in older people. The effect of demographic variables and vascular conditions offers opportunities for prevention. The association with functional impairment is useful to evaluate the burden of disability and healthcare demands.

Prognosis with dementia in Europe: A collaborative study of population-based cohorts. Neurologic Diseases in the Elderly Research Group.

The effect of dementia on time to death and institutionalization in elderly populations is of importance to resource planning, as well as to patients and their carers. The authors report a collaborative reanalysis of nine population-based studies conducted in Europe to compare dementia cases and noncases in risk of and time to death and to institutionalization. Prevalent and incident cases were more likely than noncases to reside in an institution at baseline and were more likely to enter institutional care. Prevalent cases also had over twice the risk of death compared to noncases and survival for men with dementia was consistently lower than that for women with dementia of the same age group.

Prevalence of Parkinson's disease in Europe: A collaborative study of population-based cohorts. Neurologic Diseases in the Elderly Research Group.

The results of seven population-based studies were examined separately and pooled to obtain age- and sex-specific estimates of the prevalence of PD. An in-person screening instrument and diagnostic clinical examination were used to detect potential PD cases. The overall prevalence (per 100 population) in persons 65 years of age and older was 1.8, with an increase from 0.6 for those age 65 to 69 years to 2.6 for those 85 to 89 years. There were no sex differences in prevalence of PD.

Education and the risk for Alzheimer's disease: sex makes a difference. EURODEM pooled analyses. EURODEM Incidence Research Group.

The hypothesis that a low educational level increases the risk for Alzheimer's disease remains controversial. The authors studied the association of years of schooling with the risk for incident dementia and Alzheimer's disease by using pooled data from four European population-based follow-up studies. Dementia cases were identified in a two-stage procedure that included a detailed diagnostic assessment of screen-positive subjects. Dementia and Alzheimer's disease were diagnosed by using international research criteria. Educational level was categorized by years of schooling as low (< or =7), middle (8-11), or high (> or =12). Relative risks (95% confidence intervals) were estimated by using Poisson regression, adjusting for age, sex, study center, smoking status, and self-reported myocardial infarction and stroke. There were 493 (328) incident cases of dementia (Alzheimer's disease) and 28,061 (27,839) person-years of follow-up. Compared with women with a high level of education, those with low and middle levels of education had 4.3 (95% confidence interval: 1.5, 11.9) and 2.6 (95% confidence interval: 1.0, 7.1) times increased risks, respectively, for Alzheimer's disease. The risk estimates for men were close to 1.0. Finding an association of education with Alzheimer's disease for women only raises the possibility that unmeasured confounding explains the previously reported increased risk for Alzheimer's disease for persons with low levels of education.

Gender differences in the incidence of AD and vascular dementia: The EURODEM Studies. EURODEM Incidence Research Group.

OBJECTIVE: To study the difference in risk for dementing diseases between men and women. BACKGROUND: Previous studies suggest women have a higher risk for dementia than men. However, these studies include small sample sizes, particularly in the older age groups, when the incidence of dementia is highest. METHODS: Pooled analysis of four population-based prospective cohort studies was performed. The sample included persons 65 years and older, 528 incident cases of dementia, and 28,768 person-years of follow-up. Incident cases were identified in a two-stage procedure in which the total cohort was screened for cognitive impairment, and screen positives underwent detailed diagnostic assessment. Dementia and main subtypes of AD and vascular dementia were diagnosed according to internationally accepted guidelines. Sex- and age-specific incidence rates, and relative and cumulative risks for total dementia, AD, and vascular dementia were calculated using log linear analysis and Poisson regression. RESULTS: There were significant gender differences in the incidence of AD after age 85 years. At 90 years of age, the rate was 81.7 (95% CI, 63.8 to 104.7) in women and 24.0 (95% CI, 10.3 to 55.6) in men. There were no gender differences in rates or risk for vascular dementia. The cumulative risk for 65-year-old women to develop AD at the age of 95 years was 0.22 compared with 0.09 for men. The cumulative risk for developing vascular dementia at the age of 95 years was similar for men and women (0.04). CONCLUSION: Compared with men, women have an increased risk for AD. There are no gender differences in risk for vascular dementia.