The role of intima-media-thickness, ankle-brachial-index and inflammatory biochemical parameters for stroke risk prediction: a systematic review

Background: Despite important advances in therapeutic approaches in stroke, the options of acute treatment are still limited. Primary prevention represents another potentially highly efficient strategy. For effective prevention the early detection of subjects at risk is of utmost importance. Coinciding with a change in current understanding of atherosclerosis as an inflammatory, cross‐organ disease, new parameters to assess the individual risk are emerging. Methods: Systematic review of the potential of selected parameters for prediction of cerebrovascular events beyond detection of traditional risk factors that might expand the repertoire of primary prevention programs in stroke. Results: An absolute carotid intima‐media thickness difference of 0.1 mm increases the future risk of stroke by 13–18%. An ankle‐brachial index <0.9 was associated with a relative risk of 2.33 (95% CI 2.02–2.68) for stroke. In patients with acute stroke and ABI values < 0.9 the risk for a new vascular event is significantly increased (HR 2.1; 95% CI 1.6–2.8). Measurements of several molecular biomarkers may be used to predict future vascular events independently of traditional risk factors. Conclusions: Based on the data presented, there is clear evidence that measurement of the ankle‐brachial index identifies subjects of increased stroke risk in primary and secondary care settings as well as of stroke recurrence in acute stroke.     

Interleukin‐6 and silent cerebral infarction in hemodialysis patients: a cross‐sectional study

Background: In patients with chronic renal failure undergoing hemodialysis (HD), silent cerebral infarctions (SCI) are associated with high mortality. Levels of interleukin‐6 (IL‐6) increase with renal dysfunction and may be a novel predictor for cerebrovascular events. We tested the hypothesis that increased IL‐6 levels correlate with the occurrence of SCI in HD patients. Methods: Using cranial magnetic resonance imaging findings, we divided 50 Japanese patients undergoing HD into two groups: with SCI (60 ± 7 years, mean ± SD, n = 27) and without SCI (60 ± 6 years, n = 23). We compared the gender, body mass index, metabolic profiles, IL‐6 levels, and smoking habits between the two groups. Results: We made the following observations: (i) The prevalence of diabetes or hypertension did not differ between the two groups, (ii) the level of IL‐6 was higher in the with‐SCI group than in the without‐SCI group (P < 0.0001), (iii) the proportion of smokers was higher in the with‐SCI group (P < 0.05), (iv) plasma level of high‐density lipoprotein cholesterol was lower, whilst uric acid level was higher, in the with‐SCI group (P < 0.05 and P < 0.05, respectively), and (v) multiple logistic regression analysis identified IL‐6 levels as being significantly associated with the presence of SCI (odds ratio 3.13, 95% CI = 1.42–7.89, P < 0.0001). Conclusions: This study indicates that patients with chronic renal failure who are maintained on HD exhibit an increased prevalence of SCI and that IL‐6 is significantly associated with the presence of SCI in HD patients.     

Cystatin C as an index of cerebral small vessel disease: results of a cross‐sectional study in community‐based Japanese elderly

Background and purpose: Recent studies have shown that kidney dysfunction is associated with cerebral small vessel disease (SVD). Although creatinine‐based estimating equations have been used as the standard measure for the evaluation of kidney function, the accuracy of these is limited in the elderly because of muscle mass decrease with aging. Cystatin C is a more useful measurement than creatinine‐based estimating equations for evaluating kidney function, however, the relationship amongst cystatin C, cognitive dysfunction, and cerebral SVD has not been fully examined in community‐based elderly. Methods: We performed a cross‐sectional study using MRI to determine the relationship amongst cystatin C, cognitive function, and cerebral SVD in a total of 604 community‐based Japanese elderly. Results: In this study, subjects with higher cystatin C levels tended to have more lacunas and higher grades of white matter lesions. Although a decline of the Mini‐Mental State Examination (MMSE) scores was associated with SVD‐related lesions, the relationship between the tertiles of cystatin C and mean MMSE scores was not statistically significant. In the logistic regression analysis, the association between cystatin C and SVD‐related lesions was statistically significant, even after adjustment for conventional risk factors and high‐sensitivity C‐reactive protein. Furthermore, subjects with higher cystatin C levels accompanied with albuminuria had a greater risk for the presence of subclinical cerebral SVD than those with lower cystatin C levels without albuminuria. Conclusions: The present study suggests that there is a close relationship between cystatin C and subclinical cerebral SVD, independently of conventional risk factors, in community‐based elderly.     

Changes in white matter fiber density and morphology across the adult lifespan: A cross‐sectional fixel‐based analysis

White matter (WM) fiber bundles change dynamically with age. These changes could be driven by alterations in axonal diameter, axonal density, and myelin content. In this study, we applied a novel fixel‐based analysis (FBA) framework to examine these changes throughout the adult lifespan. Using diffusion‐weighted images from a cohort of 293 healthy volunteers (89 males/204 females) from ages 21 to 86 years old, we performed FBA to analyze age‐related changes in microscopic fiber density (FD) and macroscopic fiber morphology (fiber cross section [FC]). Our results showed significant and widespread age‐related alterations in FD and FC across the whole brain. Interestingly, some fiber bundles such as the anterior thalamic radiation, corpus callosum, and superior longitudinal fasciculus only showed significant negative relationship with age in FD values, but not in FC. On the other hand, some segments of the cerebello‐thalamo‐cortical pathway only showed significant negative relationship with age in FC, but not in FD. Analysis at the tract‐level also showed that major fiber tract groups predominantly distributed in the frontal lobe (cingulum, forceps minor) exhibited greater vulnerability to the aging process than the others. Differences in FC and the combined measure of FD and cross section values observed between sexes were mostly driven by differences in brain sizes although male participants tended to exhibit steeper negative linear relationship with age in FD as compared to female participants. Overall, these findings provide further insights into the structural changes the brain's WM undergoes due to the aging process.     

Prevalence and risk factors for posttraumatic stress disorder: a cross‐sectional study among survivors of the Wenchuan 2008 earthquake in China

Background: The impact of the May 2008 Wenchuan earthquake, measuring a massive 8.0 on the surface wave magnitude scale, on public health in China has been significant and multifaceted. In light of extant data on prevalence and risk factors for posttraumatic stress disorder (PTSD) after other natural diasters, we collected data from the Wenchuan earthquake survivors to estimate the prevalence of PTSD and to characterize a range of PTSD risk factors. Methods: A cross‐sectional multicluster sample survey of 446 respondents (201 from the Qiang ethnic‐minority group, 245 the majority Han Chinese group) was conducted in August 2008 in Beichuan county, Sichuan province, a region that was severely affected by the earthquake. In total, 240 households were represented, with a mean of 2.2 respondents per household. Data were collected from structured interviews and the Harvard Trauma Questionnaire (HTQ) and DSM‐IV criteria were used to diagnose PTSD. Results: The prevalence of PTSD was 45.5% (203/446). Low household income, being from an ethnic minority, living in a shelter or temporary house, death in family, and household damage were factors significantly related to increased odds of PTSD. Conclusions: PTSD is common after a major disaster. Postdisaster mental health recovery programs that include early identification, ongoing monitoring, preventive and intervention programs, and sustained psychosocial support are needed for the highest‐risk population, namely, the bereaved, people without incomes and those with serious household damage. These populations may also benefit from governmental and nongovernmental programs that provide social and economic support, as suggested by earlier studies. Depression and Anxiety, 2009. © 2009 Wiley‐Liss, Inc.