Remote neurological evaluation reliably identifies patients eligible to endovascular therapy while non-eligible to intravenous thrombolysis.

INTRODUCTION/BACKGROUND: Early identification of suspected stroke patients who might be eligible for a reperfusion strategy is a daily challenge in the management of patient referrals. The aim of this study was to evaluate the performance of a remote medical assessment in identifying patients eligible for endovascular therapy (EVT) while not eligible for intravenous thrombolysis (IVT), compared with a decision based on bedside clinico-radiological data. METHODS: Patients admitted to the emergency department for acute neurological symptoms lasting for less than 24h were prospectively included. Assessment of the clinical severity and medical history was performed simultaneously by two vascular neurologists (VNs), one remotely using a mobile telemedicine solution (NOMADEEC), the other at the bedside. RACE score was calculated from the NIHSS score. At the end of the evaluation, both VNs quoted their treatment convictions (IVT/EVT). Final therapeutic decision following brain and vascular imaging was recorded and compared to remote and bedside predictions. The performances of three different conditions were evaluated: complete medical evaluation (NIHSS+medical history), NIHSS score alone, and RACE score alone. Remote and bedside performances were also compared. Diagnostic accuracy parameters (sensitivity, specificity, positive and negative predictive values) of each condition were estimated, along with their two-sided 95% binomial confidence intervals. RESULTS: Out of 215 enrolled patients, 186 had a complete evaluation, 91 (54.3%) were diagnosed with an ischemic stroke or transient ischemic attack and 46 (24.7%) had an intracranial occlusion. Considering the three conditions evaluated remotely, RACE score-based decision provided the best sensitivity 54.6% [95% CI 23.4; 83.2]/specificity 80.6% [73.9; 86.2] combination. However, the complete medical evaluation had the best specificity (88.6% [82.9; 92.9] compared to RACE scores alone (P=0.038). Remote and bedside performances did not differ (κ=0.68 [0.59; 0.77]). DISCUSSION/CONCLUSION: This real-life study performed in the setting of emergency demonstrates that remote medical evaluations including recording of extensive medical information and NIHSS examination to address patient's eligibility to revascularization treatment is swiftly feasible and is as effective as bedside prediction to EVT and/or IVT. Remote standardized medical evaluation might improve the decision of patients' primary orientation and avoid overcrowding of comprehensive stroke centres.

High glycemic variability: An underestimated determinant of stroke functional outcome following large vessel occlusion.

BACKGROUND AND PURPOSE: Early glycemic variability (GV) in diabetic patients is a poor prognosis factor following cardiovascular events. However, its influence on the course of acute ischemic stroke (AIS) with large vessel occlusion remains unclear. We investigated the relationship between high GV during acute stroke and three-month functional outcome among patients treated with combined intravenous thrombolysis and endovascular therapy for large vessel occlusion. METHODS: A single-center retrospective analysis of AIS patients with proximal intracranial occlusion who underwent thrombolysis and mechanical thrombectomy between January 2015 and May 2017. Early GV was assessed using standard deviation (SD) of blood glucose levels for the first 24hours. The main outcome was functional status at three months as defined by the modified Rankin scale (mRS). Secondary outcomes were change in NIHSS score from baseline to 24hours and occurrence of severe hemorrhagic transformation. Multivariate logistic regression analyses including GV, admission glycemia and mean glycemia were performed. RESULTS: Among the 93 patients evaluated, 26 had early high GV (≥20.9mg/dl). High GV was associated with poor functional outcome (OR=8.00; 95%CI [1.34-47.89]; P=0.02) unlike admission glycemia and mean glycemia (OR=2.92; 95%CI [0.51-16.60]; P=0.23 and OR=0.36; 95%CI [0.05-2.6]; p=0.31, respectively). High GV was not associated with NIHSS at 24hours or hemorrhagic transformation. CONCLUSION: Acute high GV contributes to poorer functional outcome following AIS related to large vessel occlusion and should be considered as a new target in acute stroke management.

Depression and routinization following stroke.

OBJECTIVE: Post-stroke depression is a frequent complication of stroke that has detrimental consequences for quality of life and functional outcomes. Daily life routines may increase feelings of security for some individuals confronted with age-related health concerns, but little information is available concerning their role following stroke. The aim of this investigation was to examine the association of depression and other psychological variables at hospitalization for stroke and behavioral routines and mood symptoms three months later using Ecological Momentary Assessment (EMA). METHODS: Forty-four patients with minor ischemic stroke were consecutively enrolled in the study. Stroke severity, handicap, depression and anxiety symptoms were assessed at baseline. EMA data acquired three months later were coded for the repetition of specific activities or behaviors occurring within the same time period across days. RESULTS: Higher baseline depression and anxiety symptom severity were significantly associated with increased behavioral routines three months after stroke. The occurrence of routines was associated with a higher level of depressive symptomatology over subsequent hours of the day. CONCLUSION: The findings demonstrate a general correlation between baseline psychological vulnerability and routines three months later, but within-day analyses suggest that routines may increase the risk of negative affect in this vulnerable population.

Influence of inflammatory status in the acute phase of stroke on post-stroke depression.

BACKGROUND: Thirty percent of stroke patients will suffer from post-stroke depression (PSD). Recent data suggest that inflammation accounts for a substantial amount of depression. Our primary objective was to assess the association between standard inflammation biomarkers in the acute phase of stroke and PSD at three months. The secondary objective was to elaborate a predictive model of PSD from clinical, biological and radiological data. METHODS: We performed a retrospective analysis of a single-centre cohort of stroke patients with a three-month follow-up. Serum levels of C-reactive protein (CRP), fibrinogen, leukocyte count and neutrophil to lymphocyte ratio (NLR) were tested at admission and at peak. Mood was assessed at three months using the depression sub-scale of the Hospital Anxiety and Depression Scale (HADS). Association between inflammation biomarkers and HADS was evaluated with multi-linear regression adjusted on clinical and radiological parameters. Logistic predictive models of PSD at three months, with and without inflammation biomarkers, were compared. RESULTS: Three hundred and forty-eight patients were included, of whom 20.06% developed PSD. Baseline and peak values of all inflammatory markers were associated with the severity of PSD at three months. Area under the curve for the receiver operating characteristic curve of PSD prediction was 0.746 (CI 95% 0.592-0.803) with selected inflammation biomarkers and 0.744 (CI 95% 0.587-0.799) without. CONCLUSION: Most inflammation biomarkers are weakly associated with PSD, adding negligible value to predictive models. While they suggest the implication of inflammation in PSD pathogenesis, they are useless for the prediction of PSD, underscoring the need for more specific biomarkers.

Acute Ischemic Stroke or Epileptic Seizure? Yield of CT Perfusion in a "Code Stroke" Situation.

BACKGROUND AND PURPOSE: The clinical differentiation between acute ischemic stroke and epileptic seizure may be challenging, and making the correct diagnosis could avoid unnecessary reperfusion therapy. We examined the accuracy of CTP in discriminating epileptic seizures from acute ischemic stroke without identified arterial occlusion. MATERIALS AND METHODS: We retrospectively identified consecutive patients in our emergency department who underwent CTP in the 4.5 hours following the development of an acute focal neurologic deficit who were discharged with a final diagnosis of acute ischemic stroke or epileptic seizure. RESULTS: Among 95 patients, the final diagnosis was epileptic seizure in 45 and acute ischemic stroke in 50. CTP findings were abnormal in 73% of the patients with epileptic seizure and 40% of those with acute ischemic stroke. Hyperperfusion was observed more frequently in the seizure group (36% versus 2% for acute ischemic stroke) with high specificity (98%) but low sensitivity (35%) for the diagnosis of epileptic seizure. Hypoperfusion was found in 38% of cases in each group and was not confined to a vascular territory in 24% of patients in the seizure group and 2% in the acute ischemic stroke group. The interobserver agreement was good (κ = 0.60) for hypo-, hyper-, and normoperfusion patterns and moderate (κ = 0.41) for the evaluation of vascular systematization. CONCLUSIONS: CTP patterns helped to differentiate acute ischemic stroke from epileptic seizure in a "code stroke" situation. Our results indicate that a hyperperfusion pattern, especially if not restricted to a vascular territory, may suggest reconsideration of intravenous thrombolysis therapy.

Contribution of routine cardiac biological markers to the etiological workup of ischemic stroke.

BACKGROUND: Optimization of the detection of atrial fibrillation following stroke is mandatory. Unfortunately, access to long-term cardiac monitoring is limited in many centers. The aim of this study was to assess the potential usefulness of three routine biological markers, troponin, D-dimers and BNP, measured in acute stroke phase in the selection of patients at risk of cardio-embolic stroke. METHODS: Troponin, D-Dimers and BNP were measured within 48 h after admission for ischemic stroke in 634 patients. Stroke mechanism was defined at the 3 months follow-up visit using ASCOD classification using a standardized work-up. Association between clinical, radiological and biological markers and stroke mechanism was evaluated using logistic regression analyses. RESULTS: 159 patients (25.1% of total study population) had a cardiac mechanism. On multivariate analysis, admission initial stroke severity (OR 1.04, 95 CI% 1.004-1.07, p < 0.05) history of heart failure (OR 3.03, 95% CI 1.19-7.73, p < 0.05), ECG abnormalities and high BNP value (OR 4.34, 95% CI 2.59-7.29, p < 0.05) were associated with pure cardiac stroke mechanism. CONCLUSION: High BNP value measured within 48 h after stroke admission is an independent predictor of cardiac stroke mechanism. Its measurement might be used to improve the selection of patients for whom further cardiologic investigations such as continuous long term ECG monitoring would be the most useful. BNP should be added to the standard admission-work-up for stroke patients.

Atrial fibrillation is a major cause of stroke in apneic patients: a prospective study.

OBJECTIVES: Large prospective studies have established that sleep-disordered breathing (SDB) is associated with an increased incidence of cardiovascular and cerebrovascular diseases. Heterogeneous results have been published about SDB and ischaemic stroke mechanism. The aim of this study was to evaluate the relationship between poststroke apneic syndrome and stroke aetiologies according to the ASCO classification. METHODS: A total of 134 patients with acute ischaemic cerebrovascular events were prospectively included. Patients with severe or infratentorial infarctions were excluded. Stroke risk factors and clinical characteristics were recorded in all patients. An overnight polygraphy was recorded (Embletta PDS). Apneic patients were defined if the polygraphy reported an apnea-hypopnea index ≥15. A standardized diagnosis workup, including serum biological investigation, evaluation of extra and intracranial arteries and heart morphology and function, was performed. Stroke mechanism was defined using ASCO and TOAST classifications. RESULTS: A proportion of 42% (56 of 134) of the patients were diagnosed as having sleep apneas. Apneic patients were older (p < 0.001), had higher BMI (p = 0.02), and more were hypertensive (p < 0.001). Using ASCO classification, a major cardioembolic source of stroke, mainly atrial fibrillation, was more frequently observed in apneic patients (41.1% vs. 20.5%, p < 0.05), while no difference was observed when considering atherosclerosis or small-vessel disease mechanisms. Univariate analysis showed that cardioembolic stroke depends on sex, age, left atrial size and OSA; however, age remained the only significant factor in multivariate analysis. CONCLUSION: This study confirms the high prevalence of sleep apneas in stroke-affected patients and identifies atrial fibrillation as a major source of stroke in this population. The strong correlation between age and SDB seems to drive the increased frequency of stroke related to atrial fibrillation in this population.

The impact of intravenous thrombolysis on outcome of patients with acute ischemic stroke after 90 years old.

BACKGROUND: Age increases the risk of mortality and poor prognosis following stroke. The benefit of intravenous thrombolysis in very old patients remains uncertain. The purpose of the study was to evaluate the efficacy and safety of thrombolysis in very old patients considering their perfusion-imaging profile. METHODS: We conducted a retrospective study including patients older than 90 y.o. admitted for an acute ischemic stroke. A computed tomography perfusion-imaging (CTP) was performed in patients who received thrombolysis. Primary outcome was the functional status at 3 months, assessed by the modified Rankin scale (mRS). Secondary outcomes were the rate of hemorrhagic transformations, duration of hospitalization and the rate of death in the first 7 days. Patients receiving thrombolysis were compared with an age-matched group of non-thrombolysed patients. RESULTS: 78 patients were included (31 % male, aged 92 ± 1.7 y.o). 37 patients received thrombolysis and among them, 30 had CTP with a mismatch. The three months mRS was not significantly different in the two groups (mRS 0-2: 5 % and 7 % in the thrombolysed and non-thrombolysed group, respectively). Hemorrhagic transformations were more frequent in the thrombolysed group (54 % versus 12 %, p = 0.002) and symptomatic intracranial hemorrhage tended to be associated with mRS at three months and death in the first 7 days. Duration of hospitalization was longer in the thrombolysed group (10 days ± 12 versus 7 days ± 9, p = 0.046). CONCLUSIONS: Patients who received thrombolysis did not have a better functional prognosis than non-thrombolysed patients.

Lucid dreams, an atypical sleep disturbance in anterior and mediodorsal thalamic strokes.

BACKGROUND: Cognitive, affective, and behavioural disturbances are commonly reported following thalamic strokes. Conversely, sleep disorders are rarely reported in this context. OBSERVATIONS: Herein, we report the cases of two young patients admitted for an ischemic stroke located in the territories of the left pre-mammillary and paramedian arteries. Together with aphasia, memory complaint, impaired attention and executive functions, they reported lucid dreams with catastrophic content or conflicting situations. CONCLUSION: Lucid dreams are an atypical presentation in thalamic strokes. These cases enlarge the clinical spectrum of sleep-wake disturbances potentially observed after an acute cerebrovascular event.

Magnetisation transfer parameters and stroke outcome.

Our aim was to evaluate the association between magnetisation transfer imaging (MTI) parameters measured 30 to 45 days after a cerebrovascular insult and post-stroke functional outcome at the same time. MTI offers the opportunity to depict subtle microstructural changes in infarcted areas. The clinical significance of the heterogeneity of brain damage within ischaemic stroke lesions is unknown. We prospectively included 58 patients with acute middle cerebral artery stroke. Diffusion-weighted imaging was performed within 12 hours after onset and the final infarct was documented by MRI with fluid-attenuated inversion recovery (FLAIR) and MTI at 30 to 45 days follow-up. We evaluated the association between MTI histogram parameters and the clinical outcome assessed by dichotomised (threshold >2) modified rankin scale (mRS) using multivariable logistic regression models adjusted on baseline characteristics. In multivariable analyses, stroke outcome was mostly driven by initial National Institutes of Health Stroke Scale (odds ratio [OR]=1.23; 95% confidence interval [CI]=1.07-1.41; p<0.01) while after adjustment of initial stroke severity magnetisation transfer ratio peak position was the only MRI parameter associated with functional status at 30 to 45 days post-stroke (OR=0.86; 95% CI=0.75-0.98; p=0.02); lower peak position values associated with higher mRS. Conversely, stroke volume measured on FLAIR sequence was not associated with stroke prognosis (p=0.87). The intensity of microstructural changes within the infarct core measured at 30 to 45 days follow-up is independently associated with the functional status evaluated at the same time. MTI and related parameters could be used as surrogate markers of treatment response in stroke clinical trials.

Caseous calcification of the mitral annulus associated with stroke: report of two cases.

OBJECTIVE: Caseous calcification of the mitral annulus (CCAM) is a rare complication of mitral annulus calcification (MAC). Whether CCAM should be considered as a cardiac source of stroke or a simple marker of atherosclerosis remains a matter of debate. METHOD: Herein, we report two patients with stroke and CCAM. RESULTS: The first one was associated with extensive aortic arch atheroma, while CCAM was the only potential cause in the second case. Transthoracic echocardiography was normal in both cases and CCAM was diagnosed on transesophageal echocardiography. CONCLUSION: These observations suggest that CCAM should be added to the list of minor cardioembolic sources of stroke but also requires a perfect control of vascular risk factors.

[Intracranial hemorrhage in three haemophilic adults: A severe complication of hemophilia]. / Hémorragie intracérébrale chez trois adultes hémophiles : une complication sévère de l'hémophilie.

BACKGROUND: Intracranial hemorrhage (ICH) complications are uncommon at hemophilic patients. OBSERVATIONS: We report three cases of ICH occurring in hemophilic patients. Contributing factors were identified in two patients: hemophilia severity, presence of inhibitor, hepatitis C virus infection, and high blood pressure. No contributing factor was identified in the last patient. CONCLUSION: Rapid diagnosis of ICH is crucial in hemophilic patients. A search for contributing factors, both those specific to hemophilia, and those favoring ICH in the general population, is essential to optimize therapeutic care. Specific substitutive treatment for the deficient factor is a difficult management challenge.

[Benefit of a short atherosclerosis prevention program on post-stroke vascular risk reduction]. / Intérêt d'un programme court de prise en charge globale de l'athérosclérose sur la réduction du risque vasculaire à distance d'un infarctus cérébral.

INTRODUCTION: Atherosclerosis is a major cause of ischemic stroke. Despite important therapeutic advances, the risk of recurrence of vascular events remains very high. The partial failure of these strategies is to some extent related to the lack of patient adherence to their treatments and to the fact that therapeutic targets are not reached. The aim of the present study was to evaluate the influence of a short atherosclerosis prevention program on vascular risk reduction in stroke patients. PATIENTS AND METHODS: Ninety-five patients with a first ischemic stroke related to atherosclerosis or with a high vascular risk profile were recruited. Three months later, a global evaluation of the atherosclerotic disease and of the vascular risk factors was performed combined with several education sessions on vascular risk factors and way of life. A follow-up evaluation was performed several months later to investigate the number of vascular events and the vascular risk profile. RESULTS: Median follow-up was 684 days after stroke. At follow-up, 91.3% of patients were taking a cholesterol-lowering drug, 95.6% an anti-thrombotic agent, and 78% an angiotensin converting enzyme inhibitor. A persistent decrease in tobacco use and an improvement in glycemic control were observed. During follow-up, 3.2% of patients died; none of the deaths were related to a vascular event. During the 22-month follow-up, 7.6% of patients experienced a major vascular event, acute coronary syndrome or stroke. CONCLUSION: Compared with results in the literature, this study illustrates the positive influence of a short atherosclerosis prevention program combining depiction of atherosclerotic lesions and education of vascular risk factors on the quality of long-term post-stroke prevention.

Atraumatic nonaneurysmal sulcal subarachnoid hemorrhages: a diagnostic workup based on a case series.

INTRODUCTION: Atraumatic and nonaneurysmal sulcal subarachnoid hemorrhage (sSAH) is a rare type of cerebrovascular disease with various etiologies previously reported in small case reports. In this study, we propose to analyze clinical presentations, imaging patterns and etiologies in a large case series of such patients in order to propose a diagnostic workup. METHODS: We retrospectively analyzed clinical and radiological data of consecutive patients with a diagnosis of atraumatic and nonaneurysmal sSAH, admitted to our institution between 2008 and 2011. All patients had both computed tomography (CT) and magnetic resonance imaging (MRI) as a part of their initial evaluation. RESULTS: 30 patients (18 women and 12 men, mean age: 60 years) were identified. The main clinical symptoms at presentation were focal and transient neurological deficit (n = 22) and thunderclap headache (n = 10). Four patients had progressive headache and 4 other had partial or generalized epileptic seizures. MRI abnormalities associated with sSAH were prior hemorrhages, microbleeds, severe leukoencephalopathy and hemosiderosis suggesting cerebral amyloid angiopathy (CAA; n = 9), vasogenic edema in parieto-occipital areas compatible with a posterior reversible encephalopathy syndrome (PRES; n = 3), cortical venous thrombosis (n = 2) and concomitant acute cortical stroke (n = 3). Other underlying causes of sSAH, not diagnosed on MRI, were reversible cerebral vasoconstriction syndrome (RCVS) based on clinical criteria and conventional angiography (n = 4), angiitis diagnosed by skin biopsy (n = 1), vascular malformation diagnosed on CT and digital subtraction angiographies (n = 3), and overanticoagulation (n = 1). Four cases remained unresolved. CONCLUSION: This study confirmed that sSAH is a rare condition related to a wide spectrum of etiologies. Combination of brain MRI and magnetic resonance angiography and eventually digital subtraction angiography allowed the identification of an underlying etiology for 87% of patients. CAA, RCVS and PRES represented more than 50% of the etiological mechanisms. Among older patients, sSAH was mainly related to CAA while in younger patients, RCVS represented the most frequent etiology.

Final cerebral infarct volume is predictable by MR imaging at 1 week.

BACKGROUND AND PURPOSE: Stroke volume, an increasingly used end point in phase II trials, is considered stationary at least 30 days after the ictus. We investigated whether information conveyed by MR imaging measurements of the "final" infarct volume could be assessed as early as the subacute stage (days 3-6), rather than waiting for the chronic stage (days 30-45). MATERIALS AND METHODS: Ninety-five patients with middle cerebral artery stroke prospectively included in a multicenter study underwent MR imaging during the first 12 hours (MR imaging-1), between days 3 and 6 (MR imaging-2), and between days 30 and 45 (MR imaging-3). We first investigated the relationship between subacute (FLAIR-2) and chronic volumes (FLAIR-3), by using a linear regression model. We then tested the relationship between FLAIR volumes (either FLAIR-2 or FLAIR-3) and functional disability, measured by the mRS at the time of MR imaging-3, by using logistic regression. The performances of the models were assessed by using the AUC in ROC. RESULTS: A linear association between log FLAIR-2 and log FLAIR-3 volumes was observed. The proportion of FLAIR-3 variation, explained by FLAIR-2, was high (R(2) = 81%), without a covariate that improved this percentage. Both FLAIR-2 and FLAIR-3 were independent predictors of mRS (OR, 0.79 and 0.73; 95% CI, 0.64-0.97 and 0.56-0.96; P = .026 and .023). The performances of the models for the association between either FLAIR volume and mRS did not differ (AUC = 0.897 for FLAIR-2 and 0.888 for FLAIR-3). CONCLUSIONS: Stroke damage may be assessed by a subacute volume because subacute volume predicts the "true" final volume and provides the same clinical prognosis.

Reliability of the ECASS radiological classification of postthrombolysis brain haemorrhage: a comparison of CT and three MRI sequences.

BACKGROUND: Postthrombolysis brain haemorrhagic transformations (HT) are often categorized with the CT-based classification of the European Cooperative Acute Stroke Study (ECASS). However, little is known about the reliability of this classification and its extension to MRI. Our objective was to compare the inter- and intraobserver reliability of this classification on CT and 3 MRI sequences. METHODS: Forty-three patients with postthrombolysis HT on CT or at least 1 of the 3 MRI sequences: fluid-attenuation inversion recovery (FLAIR), diffusion-weighted imaging (DWI), and T2* gradient recalled echo (T2*GRE) were selected. Twelve control patients without any bleeding were added to avoid a bias based on a pure HT-positive cohort. Each series of images were independently classified with the ECASS method by 6 blinded observers. Inter- and intraobserver reproducibility was categorized from poor to excellent depending on kappa values. RESULTS: The inter- and intraobserver overall concordance of the classification was good for T2*GRE, DWI and CT (kappa > 0.6) and moderate for FLAIR (kappa < 0.6). The interobserver concordance for parenchymal haematomas was excellent for T2*GRE (kappa > 0.8) and moderate for CT, FLAIR and DWI. CONCLUSION: The T2*GRE sequence is the most reproducible method to categorize postthrombolysis HT and has an excellent reliability for the severe parenchymal haematoma category, suggesting that this sequence should be used to assess HT in thrombolytic therapy trials.

Feasibility and validity of computerized ambulatory monitoring in stroke patients.

BACKGROUND: Computerized ambulatory monitoring provides real-time assessments of clinical outcomes in natural contexts, and it has been increasingly applied in recent years to investigate symptom expression in a wide range of disorders. The purpose of this study was to examine the feasibility and validity of this data collection strategy with adult stroke patients. METHODS: Forty-eight individuals (75% of the contacted sample) agreed to participate in the current study and were instructed to complete electronic interviews using a personal digital assistant 5 times per day over a 1-week period. RESULTS: More than 80% of programmed assessments were completed by the sample, and no evidence was found for fatigue effects. Expected patterns of associations were observed among daily life variables, and data collected through ambulatory monitoring were significantly correlated with standard clinic-based measures of similar constructs. CONCLUSION: Support was found for the feasibility and validity of computerized ambulatory monitoring with stroke patients. The application of these novel methods with stroke patients should provide complementary information that is inaccessible to standard hospital-based assessments and permit increased understanding of the significance of clinical results and test scores for daily life experience.

Penetrance of marked cognitive impairment in older male carriers of the FMR1 gene premutation.

BACKGROUND: Male carriers of the FMR1 premutation are at risk of developing the fragile X-associated tremor/ataxia syndrome (FXTAS), a newly recognised and largely under-diagnosed late onset neurodegenerative disorder. Patients affected with FXTAS primarily present with cerebellar ataxia and intention tremor. Cognitive decline has also been associated with the premutation, but the lack of data on its penetrance is a growing concern for clinicians who provide genetic counselling. METHODS: The Mattis Dementia Rating Scale (MDRS) was administered in a double blind fashion to 74 men aged 50 years or more recruited from fragile X families (35 premutation carriers and 39 intrafamilial controls) regardless of their clinical manifestation. Based on previous publications, marked cognitive impairment was defined by a score