Cognitive heterogeneity among community-dwelling older adults with cerebral small vessel disease.

Some degree of ischemic injury to white matter tracts occurs naturally with age and is visible on magnetic resonance imaging as focal or confluent white matter hyperintensities. Its relationship to cognition, however, remains unclear. To explore this, community-dwelling adults between the ages 55 and 80 years completed structural imaging, neuropsychological testing, and questionnaires to provide objective measures and subjective experience of executive functioning. Volumetric lesion burden derived from structural MRI identified those with significant white matter hyperintensity burden (∼10 cm3). Half of those recruited met this criterion and were designated as the cerebral small vessel disease (CSVD) group. Subjective cognitive complaints but not objective test scores differentiated adults with and without CSVD. Hierarchical clustering revealed 2 CSVD subgroups that differentiated those with impaired versus preserved executive function relative to controls. Overall these results provide some explanation for behavioral heterogeneity often observed in studies of age-related white matter changes. They also support the use of questionnaires to assess subjective cognitive complaints that may point to subtle effects of vascular pathology not evident on standardized cognitive scores.

Rates of Screening for Breast, Colorectal, and Cervical Cancers in Older People With Cognitive Impairment or Dementia: A Meta-Analysis.

Purpose: Cancer screening may not be appropriate for some older people. We compare the likelihood of screening for colorectal, breast, and cervical cancers in older people with versus without cognitive impairment or dementia. Method: Systematic search of MEDLINE, Embase, and PsycINFO (to March 9, 2018) for articles reporting screening for colon, breast, and cervical cancers in patients with and without cognitive impairment or dementia. Studies were summarized quantitatively (random effects meta-analysis), according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Results: Studies reported data 1989-2008. The rate of screening for breast cancer by mammography was lower in women with cognitive impairment or dementia compared with those without (pooled odds ratio [OR] = 0.81, 95% confidence interval [CI] = [0.71, 0.91], p = .0007, six studies, N = 18,562). The rates of screening for cervical cancer by Pap smear (pooled OR = 0.88, 95% CI = [0.71, 1.08], p = 0.22, five studies, N = 409,131) and colorectal cancer by fecal occult blood test (pooled OR = 0.87, 95% CI = [0.55, 1.38], p = .55, two studies, N = 2,718) were not significantly lower in people with cognitive impairment or dementia. Conclusion: These historical rates provide a baseline for discussions around the need for more specific guidance to assist with decisions to discontinue screening. The study also identifies a gap in reported knowledge with respect to screening under current guidelines.

Characteristics and outcomes of Canadian MD/PhD program graduates: a cross-sectional survey.

BACKGROUND: Combined MD/PhD programs provide a structured path for physician-scientist training, but assessment of their success within Canada is limited by a lack of quantitative data. We collected outcomes data for graduates of Canadian MD/PhD programs. METHODS: We developed and implemented a Web-based survey consisting of 41 questions designed to collect outcomes data for Canadian MD/PhD program alumni from 8 Canadian universities who had graduated before September 2015. Respondents were categorized into 2 groups according to whether they had or had not completed all training. RESULTS: Of the 186 eligible alumni of MD/PhD programs, 139 (74.7%) completed the survey. A total of 136/138 respondents (98.6%) had completed or were currently completing residency training, and 66/80 (82%) had completed at least 1 postgraduate fellowship. Most (58 [83%]) of the 70 respondents who had completed all training were appointed as faculty at academic institutions, and 37 (53%) had been principal investigators on at least 1 recent funded project. Among the 58 respondents appointed at academic institutions, 44/57 (77%) dedicated at least 20% of their time to research, and 25/57 (44%) dedicated at least 50% to research. During their combined degree, 102/136 respondents (75.0%) published 3 or more first-author papers, and 133/136 (97.8%) matched with their first choice of specialty. The median length of physician-scientist training was 13.5 years. Most respondents graduated with debt despite having been supported by Canadian Institutes of Health Research MD/PhD studentships. INTERPRETATION: Most Canadian MD/PhD program alumni pursued careers consistent with their physician-scientist training, which indicates that these programs are meeting their primary objective. Nevertheless, our findings highlight that a minority of these positions are research intensive; this finding warrants further study. Our data provide a baseline for future monitoring of the output of Canadian MD/PhD programs.

Role of non-government organizations in engaging medical students in research.

The continued decline in medical trainees entering the workforce as clinician-scientists has elevated the need to engage medical students in research. While past studies have shown early exposure to generate interest among medical students for research and academic careers, financial constraints have limited the number of such formal research training programs. In light of recent government budget cuts to support research training for medical students, non-government organizations (NGOs) may play a progressively larger role in supporting the development of clinician-scientists. Since 2005, the Mach-Gaensslen Foundation has sponsored 621 Canadian medical student research projects, which represents the largest longitudinal data set of Canadian medical students engaged in research. We present the results of the pre- and post-research studentship questionnaires, program evaluation survey and the 5-year and 10-year follow-up questionnaires of past recipients. This paper provides insight into the role of NGOs as stakeholders in the training of clinician-scientists and evaluates the impact of such programs on the attitudes and career trajectory of medical students. While the problem of too few physicians entering academic and research-oriented careers continues to grow, alternative-funding strategies from NGOs may prove to be an effective approach in developing and maintaining medical student interest in research.

Pathoconnectomics of cognitive impairment in small vessel disease: A systematic review.

INTRODUCTION: Cerebral small vessel disease (CSVD) is a highly prevalent condition associated with diffuse ischemic damage and cognitive dysfunction particularly in executive function and attention. Functional brain imaging studies can reveal mechanisms of cognitive impairment in CSVD, although findings are mixed. METHODS: A systematic review integrating findings from functional magnetic resonance imaging and electroencephalography in CSVD is involved. RESULTS: CSVD damages long-range white matter tracts connecting nodes within distributed brain networks. It also disrupts frontosubcortical circuits and cholinergic fiber tracts mediating attentional processes. These changes, illustrated within a model of network dynamics, synergistically relate to neurodegenerative pathology contributing to dementia. DISCUSSION: The effects of CSVD on attention and executive functioning are best understood within a network model of cognition as revealed by functional neuroimaging. Analysis of network function in CSVD can improve characterization of disease severity and treatment effects, and it can inform theoretical models of brain function.

Validity of Self-Report of Cardiovascular Risk Factors in a Population at High Risk for Stroke.

BACKGROUND: Screening for vascular risk factors is commonly assessed through self-report, despite reports of low sensitivity using this approach in healthy populations. The validity of self-reported vascular risk factors in a population at high risk for stroke has yet to be explored. AIMS: This study investigated the validity of self-reported cardiovascular risk factors (e.g., hypertension, hypercholesterolemia, and type II diabetes mellitus) in a population of patients with a recent history of high-risk transient ischemic attack or minor stroke. METHODS: Data were extracted from patient questionnaire responses and medical records (n = 101). Agreement between self-report and clinical measures (blood pressure, fasting blood glucose, lipid profile, and active medications) was assessed using estimates of sensitivity, specificity, and positive and negative predictive values for each vascular risk factor. RESULTS: Forty-nine percent of the study population inaccurately self-reported at least 1 vascular risk factor. Sensitivities of self-report for hypertension, hypercholesterolemia, and diabetes were 84.5% (confidence interval [CI]: 72.1-92.2), 57.5% (CI: 44.1-69.7), and 77.8% (CI: 57.3-90.6), respectively, while specificities were 76.7% (CI: 61.0-87.7), 83.3% (CI: 67.3-93.2), and 95.4% (CI: 87.8-98.9), respectively. Accuracy of self-report for hypercholesterolemia was significantly lower than that for diabetes (P < .001) and hypertension (P < .05), with 42.6% of those with high cholesterol under-reporting their diagnosis. Logistic regression revealed that odds of accurate self-report were greater among younger adults and males. CONCLUSIONS: These results highlight the need for clinicians, scientists, and epidemiologists to be cautious when screening for vascular risk factors using self-report measures as cross validation against objectives measures reveals poor sensitivity. Our results also highlight a lack of public education concerning these significant conditions.