Konstantinos Vemmos

Low triiodothyronine: a strong predictor of outcome in acute stroke patients.

Backgroundu2003 Low triiodothyronine (T3) has been associated with increased short‐term mortality in intensive care unit patients and long‐term mortality in patients with heart disease. The objective of this study was to investigate possible associations of thyroid hormone status with clinical outcome in patients admitted for acute stroke.

The Prognostic Value of the Modified Rankin Scale Score for Long-Term Survival after First-Ever Stroke

Background: The modified Rankin Scale (mRS) is gaining importance as a means to quantity disability following stroke, yet little is known about its usefulness as a determinant of the long-term outcome. Methods: The Athens Stroke Registry, which includes information on 1,816 first-ever stroke patients admitted to the Athens University Hospital from 1992 to 2004, was used to examine the crude and adjusted effect of the 3-month mRS score for long-term survival. The mean age was 70 years, 62% were males, and 84% had an ischemic stroke. Results: The mortality in the first 3 months exceeded 20%, but thereafter the survival declined much more slowly (∼4.5% per year). The patients with worse mRS scores had a significant excess risk of death; the effect persisted when controlling for coexistent cardiovascular problems (transient ischemic attack, claudication, heart failure and atrial fibrillation). Conclusions: These findings underscore the importance of interventions aimed at improving disability following stroke.

Adherence to the Mediterranean diet in relation to acute coronary syndrome or stroke nonfatal events: a comparative analysis of a case/case-control study.

BACKGROUNDnAlthough the role of Mediterranean diet on cardiovascular disease prevention has long been evaluated and understood, its association with the development of stroke has been rarely examined. The aim of the present work was to comparatively evaluate the association between adherence to the Mediterranean diet and the development of an acute coronary syndrome (ACS) or ischemic stroke.nnnMETHODSnDuring the period from 2009 to 2010, 1,000 participants were enrolled; 250 were consecutive patients with a first ACS, 250 were consecutive patients with a first ischemic stroke, and 500 population-based, control subjects, 1-for-1 matched to the patients by age and sex. Sociodemographic, clinical, psychological, dietary, and other lifestyle characteristics were measured. Adherence to the Mediterranean diet was assessed by the validated MedDietScore (theoretical range 0-55).nnnRESULTSnAfter various adjustments were made, it was observed that for each 1-of-55-unit increase of the MedDietScore, the corresponding odds ratio for having an ACS was 0.91 (95% CI 0.87-0.96), whereas regarding stroke, it was 0.88 (95% CI 0.82-0.94).nnnCONCLUSIONSnThe present work extended the current knowledge about the cardioprotective benefits from the adoption of the Mediterranean diet by showing an additional protective effect on ischemic stroke development.

Stroke, obesity and gender: a review of the literature.

Cerebrovascular disease constitutes one of the main causes of morbidity, disability and mortality worldwide. Obesity, a major health problem reaching global epidemic proportions, is also associated with morbidity and mortality. The present review provides an update on the current knowledge regarding the association of gender and obesity with stroke prevalence and outcome. We also discuss the areas that future research needs to point towards. In general, gender differences in relation to stroke are increasingly being recognized and evaluated. Age-specific stroke incidence is generally higher in men, except in the elderly. Women are treated less frequently with intravenous thrombolysis compared with men stroke patients and the two genders seem to respond differently to aspirin and statins. Regarding obesity, although it is a well-known predictor of cardiovascular disease, there is a growing body of evidence revealing the presence of an inverse relationship between obesity and outcome in patients with stroke or established cardiovascular disease, the so-called obesity paradox. Further research is warranted on these important topics, as human population is continuously aging and becoming more obese. In this context, the causes of gender differences in stroke prevalence and outcome and the obesity-stroke paradox should be further investigated in future studies.

Comparative analysis of a-priori and a-posteriori dietary patterns using state-of-the-art classification algorithms: A case/case-control study

OBJECTIVEnTo compare the accuracy of a-priori and a-posteriori dietary patterns in the prediction of acute coronary syndrome (ACS) and ischemic stroke. This is actually the first study to employ state-of-the-art classification methods for this purpose.nnnMETHODS AND MATERIALSnDuring 2009-2010, 1000 participants were enrolled; 250 consecutive patients with a first ACS and 250 controls (60±12 years, 83% males), as well as 250 consecutive patients with a first stroke and 250 controls (75±9 years, 56% males). The controls were population-based and age-sex matched to the patients. The a-priori dietary patterns were derived from the validated MedDietScore, whereas the a-posteriori ones were extracted from principal components analysis. Both approaches were modeled using six classification algorithms: multiple logistic regression (MLR), naïve Bayes, decision trees, repeated incremental pruning to produce error reduction (RIPPER), artificial neural networks and support vector machines. The classification accuracy of the resulting models was evaluated using the C-statistic.nnnRESULTSnFor the ACS prediction, the C-statistic varied from 0.587 (RIPPER) to 0.807 (MLR) for the a-priori analysis, while for the a-posteriori one, it fluctuated between 0.583 (RIPPER) and 0.827 (MLR). For the stroke prediction, the C-statistic varied from 0.637 (RIPPER) to 0.767 (MLR) for the a-priori analysis, and from 0.617 (decision tree) to 0.780 (MLR) for the a-posteriori.nnnCONCLUSIONnBoth dietary pattern approaches achieved equivalent classification accuracy over most classification algorithms. The choice, therefore, depends on the application at hand.

Risk Stratification for Recurrence and Mortality in Embolic Stroke of Undetermined Source

Background and Purpose— The risk of stroke recurrence in patients with Embolic Stroke of Undetermined Source (ESUS) is high, and the optimal antithrombotic strategy for secondary prevention is unclear. We investigated whether congestive heart failure, hypertension, age ≥75 years, diabetes mellitus, and stroke or transient ischemic attack (TIA; CHADS2) and CHA2DS2-VASc scores can stratify the long-term risk of ischemic stroke/TIA recurrence and death in ESUS. Methods— We pooled data sets of 11 stroke registries from Europe and America. ESUS was defined according to the Cryptogenic Stroke/ESUS International Working Group. Cox regression analyses were performed to investigate if prestroke CHADS2 and congestive heart failure, hypertension, age ≥75 years, diabetes mellitus, stroke or TIA, vascular disease, age 65–74 years, sex category (CHA2DS2-VASc) scores were independently associated with the risk of ischemic stroke/TIA recurrence or death. The Kaplan–Meier product limit method was used to estimate the cumulative probability of ischemic stroke/TIA recurrence and death in different strata of the CHADS2 and CHA2DS2-VASc scores. Results— One hundred fifty-nine (5.6% per year) ischemic stroke/TIA recurrences and 148 (5.2% per year) deaths occurred in 1095 patients (median age, 68 years) followed-up for a median of 31 months. Compared with CHADS2 score 0, patients with CHADS2 score 1 and CHADS2 score >1 had higher risk of ischemic stroke/TIA recurrence (hazard ratio [HR], 2.38; 95% confidence interval [CI], 1.41–4.00 and HR, 2.72; 95% CI, 1.68–4.40, respectively) and death (HR, 3.58; 95% CI, 1.80–7.12, and HR, 5.45; 95% CI, 2.86–10.40, respectively). Compared with low-risk CHA2DS2-VASc score, patients with high-risk CHA2DS2-VASc score had higher risk of ischemic stroke/TIA recurrence (HR, 3.35; 95% CI, 1.94–5.80) and death (HR, 13.0; 95% CI, 4.7–35.4). Conclusions— The risk of recurrent ischemic stroke/TIA and death in ESUS is reliably stratified by CHADS2 and CHA2DS2-VASc scores. Compared with the low-risk group, patients in the high-risk CHA2DS2-VASc group have much higher risk of ischemic stroke recurrence/TIA and death, approximately 3-fold and 13-fold, respectively.

Comparative Analysis of Cardiovascular Disease Risk Factors Influencing Nonfatal Acute Coronary Syndrome and Ischemic Stroke

The aim of the present work was to compare the influence of classic cardiovascular disease (CVD) risk factors on the development of acute coronary syndrome (ACS) and ischemic stroke. During 2009-2010, 1,000 participants were enrolled: 250 were consecutive patients with a first ACS, 250 were consecutive patients with a first ischemic stroke, and 500 were population-based, control subjects, 1-for-1 matched to the patients by age and gender. The following CVD risk factors were evaluated: smoking/passive smoking, family history of CVD, physical inactivity, hypertension, hypercholesterolemia, diabetes mellitus, presence of overweight and obesity, trait anxiety (assessed with the Spielberger State-Trait Anxiety Inventory form Y-2), and adherence to the Mediterranean diet (assessed by the MedDietScore). Furthermore, participants graded the perceived significance of the aforementioned factors, using a scale from 1 (not important) to 9 (very important). The risk factors with the highest effect size for ACS, as determined by the Wald criterion, were smoking and hypercholesterolemia; regarding stroke, they were anxiety and family history of CVD (all p <0.01). When the odds ratios of each factor for ACS and stroke were compared, insignificant differences were observed, except for smoking. On the basis of the participants health beliefs, smoking and stress emerged as the most important risk factors, whereas all subjects graded passive smoking as a least important factor. In conclusion, similarities of the risk factors regarding ACS and ischemic stroke facilitate simultaneous primary prevention measures.

Adherence to the Mediterranean Diet in Relation to Ischemic Stroke Nonfatal Events in Nonhypercholesterolemic and Hypercholesterolemic Participants Results of a Case/Case–Control Study

The aim of the present work was to evaluate the association between adherence to the Mediterranean diet and the development of ischemic stroke according to cholesterol levels. During 2009-2010, 500 participants were enrolled; 250 were consecutive patients (77 ± 9 years, 55.6% men) with a first ischemic stroke and 250 population-based, control participants, matched to the patients by age and sex. Sociodemographic, clinical, dietary, and other lifestyle characteristics were measured. Adherence to the Mediterranean diet was assessed by the validated MedDietScore (theoretical range: 0-55). After various adjustments, each 1/55 unit increase in the MedDietScore was associated with 17% lower likelihood of having an ischemic stroke in nonhypercholesterolemic participants (95%CI: 0.72-0.96) and 10% lower likelihood in participants with hypercholesterolemia (95%CI: 0.81-0.99). The present work highlights the cardioprotective benefits from the adoption of the Mediterranean diet, by showing its beneficial effect regarding ischemic stroke development, regardless of the presence of hypercholesterolemia.

Temporal trends and associated factors for pre-hospital and in-hospital delays of stroke patients over a 16-year period: the Athens study.

Background: The management and outcome of acute ischemic stroke changed dramatically after the introduction of intravenous thrombolysis. However, relatively few patients have received thrombolytic treatment, mainly due to pre-hospital and/or in-hospital delays. Although the causes of these delays have been adequately studied, their change over a long period has not. Methods: All acute first-ever stroke patients (n = 2,746) presenting to our academic center from 1993 to 2008 were prospectively documented in a computerized stroke data bank. The time from symptoms onset to presentation at the emergency room and to acquisition of a brain CT was calculated. Time trends over this period as well as the factors affecting them were analyzed. Results: The final study cohort consisted of 2,326 acute stroke patients after excluding 302 patients with an unknown time of stroke onset and 118 who suffered a stroke during hospitalization for another illness. Over the 16-year period, the median time from stroke onset to presentation at the emergency room decreased significantly from 3.15 h (interquartile range 1.30–10.30) to 2.00 h (range 1.00–4.00) (p < 0.001). The median time from emergency room presentation to CT scan completion also decreased significantly (p < 0.001) from 12.3 h (range 4.1–29.8) to 1.0 h (range 0.31–2.77). As a result, the proportion of patients having a CT scan within 4 h of stroke onset increased significantly from 8.6% in 1993–1994 to 53.6% in 2007–2008 (p < 0.001). Thrombolytic treatment was applied in 4.15% of all ischemic stroke patients in the period from 2003 to 2008. Along with other significant factors, use of an emergency medical service was associated with a 57% greater chance of presenting within 3 h after symptoms onset. Conclusions: These results suggest a continued improvement in pre-hospital and in-hospital delays for stroke management. Public awareness and education regarding medical and paramedical services are necessary for the best early management of acute stroke patients.

Severity and outcome of acute stroke in women: relation to adrenal sex steroid levels.

Adrenal sex steroids exert diverse metabolic and neurobiological actions. Their levels have been associated with cardiovascular disease, but data concerning cerebrovascular disease are lacking. The objective of our study was to investigate the role of adrenal sex steroids in a female population suffering an acute stroke. We addressed the question of whether their levels are associated with disease severity and prognosis. A 2-year cohort study was performed in 2 tertiary hospitals, where we prospectively studied 302 consecutive postmenopausal female patients hospitalized for an acute stroke. Neurological severity on admission was assessed by the National Institutes of Health Stroke Scale; and handicap 1 month after stroke, with the modified Rankin Scale. Δ4-androstenedione levels were positively and dehydroepiandrosterone sulfate was inversely associated with stroke severity (r = 0.142, P = .014 and r = -0.153, P = .008, respectively), and both parameters remained as significant determinants even after entering other confounders in the multivariate model (r = 0.118, P = .039 and r = -0.150, P = .011, respectively). Levels of Δ4-androstenedione were significantly associated with 1-month mortality in the multivariate analysis (odds ratio with 95% confidence intervals: 1.540 [1.107-2.138)], P = .010). Δ4-androstenedione and dehydroepiandrosterone sulfate levels were associated with poor outcome in the univariate analysis, that is, combined severe handicap (modified Rankin Scale ≥4) and death, 1 month poststroke, although this was not significant in the multivariate analysis. Adrenal sex steroids, and especially Δ4-androstenedione, are significantly associated with stroke severity on admission and short-term prognosis among female stroke subjects. Well-designed prospective studies will further clarify their role in cerebrovascular disease.