Prophylactic Hydroxyurea Treatment Is Associated with Improved Cerebral Hemodynamics as a Surrogate Marker of Stroke Risk in Sickle Cell Disease: A Retrospective Comparative Analysis

Sickle cell disease (SCD) increases the incidence of childhood stroke eighty-fold. Stroke risk can be estimated by measurement of the blood velocity through the middle cerebral artery (MCA) using transcranial doppler ultrasound (TCD). A high MCA blood velocity indicates increased stroke risk due to cerebral vasculopathy, and first-line treatment to prevent primary or recurrent strokes in high-risk children with SCD has classically been chronic blood transfusions. Research has more recently shown that many of these patients may safely transition from transfusions to oral hydroxyurea (HU) treatment while maintaining a decreased risk of stroke. However, the effect on stroke risk of truly prophylactic HU treatment beginning in infancy, prior to the onset of cerebral vasculopathy, is less well understood. Our retrospective study aimed to document the long-term effects of HU treatment compared with no HU treatment in children with SCD, using TCD measurements as our primary outcome and a surrogate marker of stroke risk. Our results showed that when accounting for age-related variability and duration of treatment, prophylactic HU treatment was independently associated with lower TCD MCA velocities compared with no HU treatment, providing further evidence supporting its early initiation for patients with SCD.

Middle Cerebral Artery Pulsatility Index as Predictor of Cognitive Impairment in Hypertensive Patients

Background: Cognitive impairment is a manifestation of cerebrovascular disease regarding hypertension and other degenerative diseases which has become a global health issue due to increased life expectancy. Recently, the gold standard used for diagnosing vascular cognitive impairment (VCI) has required a combination of the neurophysiological approach and magnetic resonance imaging (MRI). The Neurosonological approach, involving measuring the pulsatility index (PI) of the middle cerebral artery (MCA) using Trans Cranial Doppler (TCD), can hopefully be used as an affordable alternative predictor of VCI in patients with hypertension.

Methods: A cross-sectional study was conducted at the Outpatient Clinic of the Department of Neurology in Ciptomangunkusumo Hospital, Jakarta. Sixty-six hypertensive subjects with no macrovascular complication were selected and screened using the Montreal Cognitive Assesment-Indonesia version (MoCA-Ina) to determine their cognitive status. Subjects were categorized into two groups; subjects with scores ≥26 were classified as the normal cognitive group, while subjects with scores <26 were classified as the cognitive impairment group. Both groups then underwent TCD examination to determine bilateral MCA PI.

Results: There was a significant difference between MCA PI in both groups; it was higher in the cognitive impairment group than normal group (p < 0.001). Subjects with an increased left MCA PI were more likely to suffer cognitive impairment than those with an increased right MCA PI.

Conclusion: MCA PI can be used as a predictor for cognitive impairment in hypertensive subjects.

OPLS statistical model versus linear regression to assess sonographic predictors of stroke prognosis

The objective of the present study was to assess the comparable applicability of orthogonal projections to latent structures (OPLS) statistical model vs traditional linear regression in order to investigate the role of trans cranial doppler (TCD) sonography in predicting ischemic stroke prognosis. The study was conducted on 116 ischemic stroke patients admitted to a specialty neurology ward. The Unified Neurological Stroke Scale was used once for clinical evaluation on the first week of admission and again six months later. All data was primarily analyzed using simple linear regression and later considered for multivariate analysis using PLS/OPLS models through the SIMCA P+12 statistical software package. The linear regression analysis results used for the identification of TCD predictors of stroke prognosis were confirmed through the OPLS modeling technique. Moreover, in comparison to linear regression, the OPLS model appeared to have higher sensitivity in detecting the predictors of ischemic stroke prognosis and detected several more predictors. Applying the OPLS model made it possible to use both single TCD measures/indicators and arbitrarily dichotomized measures of TCD single vessel involvement as well as the overall TCD result. In conclusion, the authors recommend PLS/OPLS methods as complementary rather than alternative to the available classical regression models such as linear regression.