Prathiba Shammi

Brain derived neurotrophic factor, cardiopulmonary fitness and cognition in patients with coronary artery disease

OBJECTIVE To assess serum brain derived neurotrophic factor (BDNF) concentrations as a correlate of cardiopulmonary fitness and as a predictor of cognitive performance in subjects with coronary artery disease (CAD). METHODS Serum BDNF concentrations were assayed by ELISA and fitness was assessed using a standardized exercise stress test. The Mini Mental Status Examination (MMSE), California Verbal Learning Test 2nd Ed., Stroop, Trail Making Test B and the Digit Symbol-Coding task were administered. The val66met BDNF genotype and serum interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α) concentrations were determined as potential confounders. RESULTS In subjects with CAD (n=88; 85.2% male, mean age 62.8±10.5 yr), cardiopulmonary fitness was associated with higher serum BDNF concentrations (β=.305, p=.013). Higher serum BDNF concentrations were associated with higher MMSE scores (F(1,87)=15.406, p<.0005) and better performance on the Digit Symbol-Coding task (F(1,87)=9.620, p=.003). IL-6, TNF-α and the val66met genotype did not influence these results. CONCLUSION Serum BDNF concentrations were associated with cardiopulmonary fitness, psychomotor processing speed and overall cognition in subjects with CAD.

Cardiopulmonary fitness is associated with cognitive performance in patients with coronary artery disease.

OBJECTIVES: To investigate the association between cardiopulmonary fitness and cognitive performance in subjects with coronary artery disease (CAD).

The utility of the Mini-Mental Status Exam in older adults with traumatic brain injury

Primary objective: To assess the utility of the Mini-Mental Status Examination (MMSE) among the older TBI population. Methods and procedures: The MMSE and a number of other neuropsychological tests were administered to forty-three adults aged 50 and over one year following mild to moderate TBI. The sensitivity, specificity, and predictive value of the MMSE were evaluated in relation to these tests. Main outcomes and results: The domains of the MMSE generally exhibited low sensitivity while high specificity was demonstrated by Attention and Language. Positive predictive value was high only for Language but negative predictive value was moderate to high for all domains. Conclusions: These results suggest that one year following mild to moderate TBI among older adults, the MMSE should not be used to identify those with cognitive impairment; if administered, a perfect score on a component of the MMSE suggests that enhanced testing in that given domain may not reveal further impairment. A small sample size and a small number of those impaired limit our results.

Verbal memory performance and completion of cardiac rehabilitation in patients with coronary artery disease.

Objective: To assess cognitive performance as a predictor of noncompletion of cardiac rehabilitation (CR) using a standardized verbal memory test. Methods: This was a prospective cohort study of consecutive patients with coronary artery disease (n = 131) entering 1-year outpatient CR between April 2007 and May 2009. Verbal memory performance was assessed using the California Verbal Learning Test, Second Edition. Attendance at weekly CR sessions was recorded, and completion or noncompletion was determined according to comprehensive CR criteria. Depression was diagnosed according to DSM-IV criteria as a possible confounder. Results: Verbal memory performance at entry into CR differed significantly (F(1,130) = 7.80, p =.006) between noncompleters and completers (mean [SD] cumulative California Verbal Learning Test, Second Edition, score, −1.15 [2.59] versus 0.47 [3.12]) in analysis of covariance controlling for pertinent clinical confounders. Better verbal memory performance predicted a reduced risk of noncompletion (hazard ratio [HR] = 0.86, 95% confidence interval [CI] = 0.77-0.96, p =.009) in time-to-event analysis adjusted for depression (HR = 2.62, 95% CI = 1.33-5.17, p =.006) and smoking history (HR = 2.03, 95% CI = 0.98-4.22, p =.06). A post hoc analysis suggested that better verbal memory performance predicted a reduced risk of noncompletion for medical reasons (HR = 0.83, 95% CI = 0.70-0.99, p =.03). Conclusions: Poorer verbal memory performance was associated with an increased risk of noncompletion of CR among participants with coronary artery disease. Further studies exploring practical methods for screening and targeted support might improve rehabilitation outcomes.CR = cardiac rehabilitation; CAD = coronary artery disease; MMSE = Mini-Mental Status Examination; CABG = coronary artery bypass graft; CES-D = Center for Epidemiologic Studies Depression scale; CVLT-II = California Verbal Learning Test, Second Edition; HR = hazard ratio

Higher Cortisol Predicts Less Improvement in Verbal Memory Performance after Cardiac Rehabilitation in Patients with Coronary Artery Disease

Objective. While physical activity can improve verbal memory performance in subjects with coronary artery disease (CAD), there is large variability in response. Elevated cortisol production has been suggested to negatively affect verbal memory performance, yet cortisol concentrations have not been assessed as a predictor of response to exercise intervention in those with CAD. Methods. CAD patients participating in a one-year cardiac rehabilitation program were recruited. Memory was assessed with the California Verbal Learning Test second edition at baseline and one year. Cortisol was measured from a 20 mg, 3.0 cm hair sample collected at baseline. Results. In patients with CAD (n = 56, mean ± SD age = 66 ± 11, 86% male), higher cortisol (hair cortisol concentrations ≥ 153.2 ng/g) significantly predicted less memory improvement (F1,50 = 5.50, P = 0.02) when controlling for age (F1,50 = 0.17, P = 0.68), gender (F1,50 = 2.51, P = 0.12), maximal oxygen uptake (F1,50 = 1.88, P = 0.18), and body mass index (F1,50 = 3.25, P = 0.08). Conclusion. Prolonged hypothalamic pituitary adrenal axis activation may interfere with exercise-related improvements in memory in CAD.

Differentiating between visual hallucination-free dementia with Lewy bodies and corticobasal syndrome on the basis of neuropsychology and perfusion single-photon emission computed tomography.

IntroductionDementia with Lewy bodies (DLB) and Corticobasal Syndrome (CBS) are atypical parkinsonian disorders with fronto-subcortical and posterior cognitive dysfunction as common features. While visual hallucinations are a good predictor of Lewy body pathology and are rare in CBS, they are not exhibited in all cases of DLB. Given the clinical overlap between these disorders, neuropsychological and imaging markers may aid in distinguishing these entities.MethodsProspectively recruited case–control cohorts of CBS (n =31) and visual hallucination-free DLB (n =30), completed neuropsychological and neuropsychiatric measures as well as brain perfusion single-photon emission computed tomography and structural magnetic resonance imaging (MRI). Perfusion data were available for forty-two controls. Behavioural, perfusion, and cortical volume and thickness measures were compared between the groups to identify features that serve to differentiate them.ResultsThe Lewy body with no hallucinations group performed more poorly on measures of episodic memory compared to the corticobasal group, including the delayed and cued recall portions of the California Verbal Learning Test (F (1, 42) =23.1, P <0.001 and F (1, 42) =14.0, P =0.001 respectively) and the delayed visual reproduction of the Wechsler Memory Scale-Revised (F (1, 36) =9.7, P =0.004). The Lewy body group also demonstrated reduced perfusion in the left occipital pole compared to the corticobasal group (F (1,57) =7.4, P =0.009). At autopsy, the Lewy body cases all demonstrated mixed dementia with Lewy bodies, Alzheimer’s disease and small vessel arteriosclerosis, while the corticobasal cases demonstrated classical corticobasal degeneration in five, dementia with agyrophilic grains + corticobasal degeneration + cerebral amyloid angiopathy in one, Progressive Supranuclear Palsy in two, and Frontotemporal Lobar Degeneration-Ubiquitin/TAR DNA-binding protein 43 proteinopathy in one. MRI measures were not significantly different between the patient groups.ConclusionsReduced perfusion in the left occipital region and worse episodic memory performance may help to distinguish between DLB cases who have never manifested with visual hallucinations and CBS at earlier stages of the disease. Development of reliable neuropsychological and imaging markers that improve diagnostic accuracy will become increasingly important as disease modifying therapies become available.