Association of Multi-Domain Factors with Cognition in the UK Biobank Study

BACKGROUND

Dementia is a multifactorial syndrome attributable to a combination of vascular risk factors, lifestyle factors and neurodegeneration. However, little is known about the relative contribution of all these factors and their combined effects on cognition among the older population.

OBJECTIVE

To examine the association of four domains of risk factors (sociodemographic, vascular risk factors, neuroimaging markers, lifestyle and psychosocial factors) with cognition in older adults.

DESIGN

A cross-sectional study.

SETTING

Data was obtained from a large-scale population-based study, UK Biobank study, at the first imaging visit assessment.

PARTICIPANTS

Participants are citizen or permanent residents of UK, aged 60 years old and above.

MEASURES

Cognitive function was assessed using the general cognitive ability score (g-factor score) derived from principal components analysis estimates of six cognitive tests. Associations with cognition were examined using multivariable linear regression for each domain and in combination.

RESULTS

The study included 19,773 participants (mean age 68.5 ± 5.3 years SD, 9,726 (49%) male). Participants with lower cognitive scores (poorer cognition) were older, female, non-whites individuals, less educated and more socially deprived than participants with better cognitive scores. Participants with lower cognitive scores also tended to have higher vascular risk factors, lower brain volumes and more adverse lifestyle behaviours. The multivariable analysis found associations between adverse lifestyle and psychosocial factors with poorer cognition, i.e., being obese by measure of body fat percentage, having diabetes, higher white matter hyperintensity volume, increased sedentary screen time watching TV, being socially isolated and having depression were independently associated with poorer cognition. While larger hippocampal volume, having optimal sleep duration, adherence to a heathy diet, current and former alcohol drinking, increased wine consumption and sedentary screen time using a computer were associated with better cognition.

CONCLUSION

A combination of adverse lifestyle and psychosocial factors were independently associated with poorer cognition in older adults. Findings in this study can potentially support public health communications to promote cognitive function and independence among older adults. This research has been conducted using the UK Biobank Resource under Application Number 71022.

Arterial Spin-Labeling Parameters and Their Associations with Risk Factors, Cerebral Small-Vessel Disease, and Etiologic Subtypes of Cognitive Impairment and Dementia

BACKGROUND AND PURPOSE

Cerebral small-vessel disease may alter cerebral blood flow (CBF) leading to brain changes and, hence, cognitive impairment and dementia. CBF and the spatial coefficient of variation can be measured quantitatively by arterial spin-labeling. We aimed to investigate the associations of demographics, vascular risk factors, location, and severity of cerebral small-vessel disease as well as the etiologic subtypes of cognitive impairment and dementia with CBF and the spatial coefficient of variation.

MATERIALS AND METHODS

Three hundred ninety patients with a diagnosis of no cognitive impairment, cognitive impairment no dementia, vascular cognitive impairment no dementia, Alzheimer disease, and vascular dementia were recruited from the memory clinic. Cerebral microbleeds and lacunes were categorized into strictly lobar, strictly deep, and mixed-location and enlarged perivascular spaces into the centrum semiovale and basal ganglia. Total and region-specific white matter hyperintensity volumes were segmented using FreeSurfer. CBF (n = 333) and the spatial coefficient of variation (n = 390) were analyzed with ExploreASL from 2D-EPI pseudocontinuous arterial spin-labeling images in white matter (WM) and gray matter (GM). To analyze the effect of demographic and vascular risk factors as well as the location and severity of cerebral small-vessel disease markers on arterial spin-labeling parameters, we constructed linear regression models, whereas logistic regression models were used to determine the association between arterial spin-labeling parameters and cognitive impairment no dementia, vascular cognitive impairment no dementia, Alzheimer disease, and vascular dementia.

RESULTS

Increasing age, male sex, hypertension, hyperlipidemia, history of heart disease, and smoking were associated with lower CBF and a higher spatial coefficient of variation. Higher numbers of lacunes and cerebral microbleeds were associated with lower CBF and a higher spatial coefficient of variation. Location-specific analysis showed mixed-location lacunes and cerebral microbleeds were associated with lower CBF. Higher total, anterior, and posterior white matter hyperintensity volumes were associated with a higher spatial coefficient of variation. No association was observed between enlarged perivascular spaces and arterial spin-labeling parameters. A higher spatial coefficient of variation was associated with the diagnosis of vascular cognitive impairment no dementia, Alzheimer's disease, and vascular dementia.

CONCLUSIONS

Reduced CBF and an increased spatial coefficient of variation were associated with cerebral small-vessel disease, and more specifically lacunes, whereas cerebral microbleeds and white matter hyperintensities were associated with WM-CBF and GM spatial coefficient of variation. The spatial coefficient of variation was associated with cognitive impairment and dementia, suggesting that hypoperfusion might be the key underlying mechanism for vascular brain damage.

Comparison between Appendicular Skeletal Muscle Index DXA Defined by EWGSOP1 and 2 versus BIA Tengvall Criteria among Older People Admitted to the Post-Acute Geriatric Care Unit in Italy

This study aims to assess the agreement between the appendicular skeletal muscle index (ASMI) and dual-energy X-ray absorptiometry (DXA) using a single frequency bioelectrical impedance analysis (BIA) to assess criteria. Moreover, we used the European working group on sarcopenia in older people 1 (EWGSOP1), EWGSOP2, and the Tengvall equation to estimate a low prevalence in ASMI (under the cutoff criteria). We examined a sample of 765 elderly individuals (27.8% male and 72.2% female, aged 82 ± 8.2 years). Based on the cutoff identified by Tengvall, EWGSOP1, and EWGSOP2, the results showed that the prevalence of low ASMI in females was 10.1%, 11.4%, and 9.2%, respectively, and 98.1%, 30.5%, and 23.5% in males, respectively. Moreover, low ASMI prevalence under each diagnostic criterion and body mass index (BMI) was calculated. For BMI < 25 kg/m2, the ASMI prevalence was 39.9%, 25.9%, and 20.6%, as determined using Tengvall, EWGSOP1, and EWGSOP2, respectively, and for BMI > 25 kg/m2, the ASMI prevalence was 29.0%, 6.6%, and 5.2%. The percentage of agreement and Cohen's Kappa with the corresponding p-value between Tengvall and EWGSOP1 was 70.1% (p < 0.001). Between Tengvall and EWGSOP2, it was 69.4% (p < 0.001). Between EWGSOP1 and EWGSOP2, it was 96.5% (p < 0.001). Regarding gender, low ASMI prevalence in males was higher than in females. Moreover, in females, the prevalence was comparable among the three diagnostic criteria, while in males, it was significantly higher under Tengvall than the other two criteria. The application of the Tengvall formula with a single frequency BIA should be revised in terms of application for assessing low ASMI in elderly patients.

Computed tomography and neurological soft signs in obsessive-compulsive disorder

Computed tomography was used to compare the following three groups: obsessive-compulsive disorder (OCD) patients with high scores on a soft neurological sign examination, OCD patients with low soft neurological sign scores, and control subjects. Neuranatomical structures were measured using quantitative volumetric analysis. OCD patients with high soft sign scores had significantly increased ventricular volumes compared with OCD patients with low soft sign scores and control subjects. Caudate and lenticular nucleus volumes did not differ between groups.

Abnormal cranial magnetic resonance imaging scans in sickle-cell disease. Neurological correlates and clinical implications

OBJECTIVE

Eight asymptomatic patients with sickle-cell disease (SCD) with magnetic resonance imaging (MRI) abnormalities consistent with cerebral infarcts (group 1) and eight asymptomatic patients with SCD with normal MRI scans (group 2) were followed up to assess the neurological correlates and the clinical outcome.

DESIGN

Patients in the two cohorts underwent clinical evaluations and xenon 133 regional cerebral blood flow (rCBF) studies within 1 month of the entry MRI. This study sequence was repeated up to 5 years later. Neuropsychological studies also were performed in six group 1 patients and eight group 2 patients at the end of the study.

SETTING

The patients were recruited from the Comprehensive Sickle Cell Center at Columbia University, New York, NY.

PATIENTS

All patients had SCD, hemoglobin SS, and normal findings on clinical evaluation at entry. The group 1 cohort had clinically silent MRI abnormalities consistent with cerebral infarction. The group 2 cohort was age matched to group 1 and had normal MRI studies.

INTERVENTIONS

None.

MAIN OUTCOME MEASURE

The natural history of MRI abnormalities and the neurological correlates were assessed to determine the predictive value of subclinical MRI lesions as a risk factor for clinically apparent stroke.

RESULTS

The mean duration of MRI follow-up was 3.7 years. In group 1, four patients (50%) demonstrated progressive MRI abnormalities and three patients (38%) became clinically symptomatic. In group 2, findings for all patients remained normal on clinical and radiological examination. Both groups had markedly elevated rCBF values. Individual rCBF differences correlated with the specific MRI abnormalities. The psychometric study results were similar in the two cohorts. Eighty-three percent of group 1 and 88% of group 2 patients had defective scores in one or more areas of cognitive functioning. Three patients met cognitive criteria for dementia.

CONCLUSIONS

Cranial MRI abnormalities have important prognostic implications even when detected in clinically asymptomatic patients. Cognitive abnormalities exist in patients with SCD even in the absence of MRI abnormalities or clinical stroke.

Focal headache during balloon inflation in the vertebral and basilar arteries

BACKGROUND AND PURPOSE

Headache may be seen in acute cerebrovascular disease. The significance of localized headache in association with vertebrobasilar disease has not been recognized.

SUMMARY OF REPORT

We describe a patient with a cerebellar arteriovenous malformation who underwent intravascular balloon occlusion of the vertebral and basilar artery. He developed reproducible patterns of referred pain with balloon inflation at specific sites.

CONCLUSIONS

Well localized head pain in the setting of acute stroke should alert physicians to the possibility of localized arterial injury. The pattern seen in this patient has been documented in experimental situations, and should be of use in the setting of acute stroke.

Structural brain imaging abnormalities associated with schizophrenia and partial trisomy of chromosome 5

Chromosomal abnormalities occurring in association with mental illness provide a unique opportunity to study the interaction of genetic abnormalities and the brain in mental illness. Four individuals from a family in which schizophrenia was found to cosegregate with a partial trisomy of chromosome 5 were studied with computed tomography and magnetic resonance imaging. Temporal lobe atrophy was found in the two trisomic males and in the asymptomatic balanced translocation female. In addition, a large cavum septum pellucidum and a cavum vergae were found in the older trisomic individual. Scans from the normal male were free of abnormalities. These results suggest that molecular studies of the translocation breakpoints in this chromosomal abnormality may be of interest, and encourage further studies of brain structure in other chromosomal abnormalities associated with psychosis.

A prospective controlled study of magnetic resonance imaging of the brain in gay men and parenteral drug users with human immunodeficiency virus infection

To detect the earliest structural changes in the brain in human immunodeficiency virus (HIV) infection, 118 gay men and 115 parenteral drug users enrolled in a study of the natural history of HIV infection underwent magnetic resonance imaging evaluations. Routine T2-weighted and heavily T2-weighted scans for quantification of brain water were obtained, blinded to HIV serostatus. Atrophy and foci of increased signal did not correlate with any medical, immunologic, neurologic, or neuropsychologic parameters in the group as a whole, or in the gay men or parenteral drug user subgroups. Three subjects had progressive multifocal leukoencephalopathy and one had central nervous system lymphoma. In a subgroup in whom intracranial water percent was calculated, correlations were found with CD4 counts and CD4/CD8 ratios. We conclude that standard magnetic resonance imaging of the brain does not differentiate asymptomatic and mildly symptomatic HIV-positive individuals from HIV-negative individuals, regardless of risk group. However, intracranial water percent may distinguish HIV-positive from HIV-negative individuals because it correlates with raw CD4 counts and CD4/CD8 ratios.

Focal headache during balloon inflation in the internal carotid and middle cerebral arteries

Although a number of reports are available on the occurrence of headache in patients with ischemic cerebrovascular disease, most studies have recorded the frequency but not the specific sites of the pain. We report 18 patients who underwent balloon inflation in the distal internal carotid artery and middle cerebral artery stem during embolization therapy for intracerebral arteriovenous malformations. Eleven patients had reproducible patterns of headache during balloon inflation. Inflation in the proximal middle cerebral artery stem produced pain primarily in the ipsilateral temple, that in the middle of the middle cerebral artery stem produced pain referred primarily retro-orbitally, and inflation in the distal middle cerebral artery stem produced pain referred primarily to the forehead. Experimental studies have demonstrated similar patterns of referred pain. The fact that these areas of referred pain are so reproducible is of potentially great clinical importance in the approach to management of patients with cerebrovascular disease.

Cerebral hyperemia, stroke, and transfusion in sickle cell disease

To investigate cerebral hemodynamics in sickle cell disease (SCD), we used the 133Xenon inhalation technique of quantifying cerebral blood flow (CBF) in 67 patients. Clinical examinations and cerebral magnetic resonance imaging also were performed in all patients. Compared with age-matched healthy controls, CBF was elevated by 68% in patients, and inversely related to hematocrit. An experimental index of cerebral blood volume, pr4, was also elevated in the patients in a similar manner. Cerebral blood volume was positively correlated to CBF in SCD patients but not in controls. History of stroke and current neurologic symptoms were associated with lower flow and higher cerebral blood volume. Transfusion therapy reduced the hyperemia, the reduction being greater than expected by hematocrit elevation alone. These findings document a vasodilatory hyperemia in SCD. This dilatation may be a risk factor for ischemic distal-field infarctions, as visualized by MRI, due to a limitation of cerebrovascular reserve capacity.

Brain infarction in sickle cell anemia: magnetic resonance imaging correlates

Brain infarction is a well-known but poorly understood complication of sickle cell disease. Seventy-three sickle cell disease patients underwent neurological examinations and high-field, heavily T2-weighted axial cranial magnetic resonance image (MRI) scanning. Eighteen of the 73 had a history of stroke, defined as an acute, focal neurological sign lasting longer than 1 hour; in the event of a convulsive onset, an MRI abnormality as a correlate was necessary. Sixteen of the 18 stroke patients demonstrated focal MRI abnormalities consistent with arterial borderzone infarctions. Fifty-five of the 73 patients had no history of stroke. Six of the 55 (11%) had focal MRI abnormalities suggesting previous subclinical stroke. Five of these lesions were in borderzone regions. The distinguishing feature in 21 of the 22 patients with MRI abnormalities was the predilection for lesions in the high cortical convexity, in the general regions of arterial borderzones between the major cerebral arteries and adjacent deep white matter. The pattern of MRI lesions suggests two pathogenetic mechanisms: (1) proximal large-vessel disease with inadequate cerebral perfusion (distal field insufficiency syndrome) and (2) distal small-vessel disease (sludging syndrome).

The effects of nuclear magnetic resonance imaging on ocular tissues

Nuclear magnetic resonance, an imaging technique with great promise for detecting cerebral abnormalities, was studied to determine its possible deleterious effects on the mammalian eye. Young (3.5-week-old) Columbia-Sherman rats were exposed simultaneously to a constant magnetic field of 2.7 tesla and radio frequency pulses of 29 MHz at 800-ms intervals for six hours at field strengths representing the maximum used in a clinical setting. The six-hour exposure is many times greater than the four to six minutes currently employed in most diagnostic protocols. The animals were examined by slit-lamp biomicroscopy and ophthalmoscopy at regular intervals. Autoradiograms of lenses from animals injected with tritiated thymidine prior to exposure did not reveal any disturbances in cell-cycle kinetics. Eyes from rats not previously injected with the isotope were processed for cytopathologic analysis at various intervals. A two-year follow-up has indicated that at both the slit-lamp biomicroscopic and the light microscopic levels, there were no discernable effects on the rat eye.

Pergolide for the treatment of pituitary tumors secreting prolactin or growth hormone

We gave pergolide mesylate, a new long-acting ergot derivative with dopaminergic properties, to 47 patients with hypersecretion of prolactin or growth hormone. Single doses produced long-lasting reductions of serum prolactin levels; after 24 hours, the values remained depressed at a mean of 28.8 per cent of the base-line value. Among 41 patients (22 women and 19 men) with hyperprolactinemia who took pergolide for three months or more, prolactin levels fell to normal in 37 and remained slightly elevated in 2. In the two patients in whom the levels fell to only 38 to 52 per cent of base line, treatment was regarded as a failure. The level of growth hormone fell to a mean of 52.8 per cent of base line in patients with acromegaly who were taking 100 micrograms of pergolide per day. Among patients for whom adequate CT scans were available, definite tumor shrinkage occurred in 10 of 13 with macroadenomas and definite or probable shrinkage in 5 of 9 with microadenomas. Menses returned in 76 per cent of treated women and testosterone levels rose in 10 of 14 men. We conclude that pergolide reduces hypersecretion and shrinks most prolactin-secreting macroadenomas. In some patients long-term pergolide therapy may be superior to surgery and x-ray treatment.

Acute posterior multifocal placoid pigment epitheliopathy associated with cerebral vasculitis and homonymous hemianopia

An 18-year-old man developed acute posterior multifocal placoid pigment epitheliopathy and homonymous hemianopia. Cerebral angiography showed cerebral vasculitis probably with occipital infarction. To the best of our knowledge, this is the first reported case with such concomitant visual defects. Other published reports suggest that such cerebral vasculitis may not be unusual in acute posterior multifocal placoid pigment epitheliopathy.

Evaluation of subarachnoid hemorrhage and cerebral vasospasm by computed tomography

The CT findings in patients with subarachnoid hemorrhage include visualization of the aneurysm (10% of the cases), subarachnoid, intraventricular, or intracerebral hemorrhage (87% of cases scanned within five days), "ischemic" lucency secondary to spasm (10%), and hydrocephalus (54%).

BCNU and steroids in the viral-induced dog brain tumor

Schmidt-Ruppin strain of Rous Sarcoma was inoculated intracerebrally into 27 newborn beagle dogs. Fourteen days after viral inoculation, 13 of the dogs were given intravenous BCNU (1 mg/kg). The other 14 were given the same volume of intravenous saline in a randomized, double-blinded fashion. Ninety percent of all dogs developed intracranial tumors. Radionuclide (mercury 197) brain scans were done on each dog at 2-week intervals. Median survival was 113 days in the BCNU group and 115 days in the placebo group (P > .99). Unequivocally positive radionuclide brain scans were detected in 5 dogs treated with BCNU and in 2 of the controls. There were no gross or microscopic differences at autopsy between treated and nontreated animals. BCNU, as given in this animal brain tumor model, did not demonstrate any oncolytic effect. An improvement in sequential brain scans was detected in 2 other dogs in response to Dexamethasone, which was given in a double-blinded, cross-over controlled fashion. Computerized tomography clearly demonstrated the tumor in two cases.

Computerized tomography correlated with CSF protein concentrations

The authors present a case of hydrocephalus complicated by ventriculitis in which it was possible to correlate the numerical printout of sequential computerized tomograms (CT-Scans) with cerebrospinal fluid protein concentrations obtained by direct ventricular puncture. Different protein levels were unambiguously associated with changes in the absorption numbers on the scan but they did not bear a simple linear relationship to one another. The value of the numerical printout in diagnosis and follow-up is discussed.