Olivier Potvin

Sleep quality and 1-year incident cognitive impairment in community-dwelling older adults.

STUDY OBJECTIVES To examine in cognitively intact older men and women the associations between subjective sleep quality and 1-yr incident cognitive impairment. DESIGN Prospective cohort study. SETTING General community. PARTICIPANTS 1,664 cognitively intact individuals age 65 to 96 years. MEASUREMENTS AND RESULTS Sleep quality at baseline was measured using the Pittsburgh Sleep Quality Index (PSQI). Cognitive functioning was assessed at baseline and 12 months later using the Mini-Mental State Examination (MMSE). Incident general cognitive impairment was defined according to a follow-up MMSE score below the 15(th) percentile according to normative data and of at least 2 points below baseline. General cognitive impairments were also separated into amnestic and nonamnestic subtypes according to MMSE delayed recall performance. Associations between sleep quality indicators at baseline and incident cognitive impairment were assessed by odds ratio (OR) adjusted for age, education, baseline MMSE score, psychotropic drug use, anxiety, depressive episodes, cardiovascular conditions, and chronic diseases. Results revealed that global PSQI score was significantly linked with incident cognitive impairment (OR 1.17, 95% confidence interval (CI) 1.05-1.30) in men, but not in women. In women, sleep disturbance score (OR 2.62, 95% CI 1.41-4.86) and long sleep duration (≥ 9 hr; OR 3.70, 95% CI 1.49-9.17) were associated with nonamnestic and amnestic incident cognitive impairment, respectively. In men, short sleep duration (≤ 5 hr; OR 4.95, 95% CI 1.72-14.27) and habitual sleep efficiency score (OR 1.94, 95% CI 1.42-2.66) were associated with amnestic and general incident cognitive impairment, respectively. CONCLUSIONS Sleep quality in older adults should receive particular attention by clinicians because poor sleep quality can be an early sign of cognitive decline.

The Impact of DSM-IV Symptom and Clinical Significance Criteria on the Prevalence Estimates of Subthreshold and Threshold Anxiety in the Older Adult Population

OBJECTIVES Subthreshold anxiety refers to a condition where individuals do not meet the full symptom criteria (i.e., the number of symptoms required for a formal diagnosis is not reached) and/or do not report significant impairment or distress in functioning (i.e., the clinical significance criterion is not met). The purpose of this study was to examine how the symptom and the clinical significance criteria may affect the prevalence estimates of anxiety problems in the older adult population and whether applying these criteria results in an identifiable older group showing more severe anxiety. SETTING AND PARTICIPANTS Data came from a large representative sample of community-dwelling older adults age 65 years and older (N = 2,784). RESULTS Results showed that the 12-month prevalence rate of any anxiety problem varied from 5.6% when DSM-IV criteria for anxiety disorders were used to 26.2% when all subthreshold manifestations of anxiety were considered. Findings also indicated that when compared with respondents without anxiety, older adults presenting different manifestations of subthreshold or threshold anxiety appear to be more similar than different in their health and health behavior characteristics. CONCLUSIONS Subthreshold anxiety has a high prevalence and may cause significant impairment. Both symptom and clinical significance criteria do not perfectly discriminate between older adults with or without a severe anxiety problem presenting comorbid disorders and needing psychiatric help.

Anxiety, Depression, and 1-Year Incident Cognitive Impairment in Community-Dwelling Older Adults

OBJECTIVES: To examine in men and women the independent associations between anxiety and depression and 1‐year incident cognitive impairment and to examine the association of cognitive impairment, no dementia (CIND) and incident cognitive impairment with 1‐year incident anxiety or depression.

Subjective sleep characteristics associated with anxiety and depression in older adults: a population-based study

Sleep complaints are often associated with anxiety and depression, but the specific complaints related to each syndrome are poorly characterized, especially in older adults. The objective was to identify subjective sleep characteristics specific to anxiety and depression in this population.

DNA methylation and single nucleotide variants in the brain-derived neurotrophic factor (BDNF) and oxytocin receptor (OXTR) genes are associated with anxiety/depression in older women.

Background: Environmental effects and personal experiences could be expressed in individuals through epigenetic non-structural changes such as DNA methylation. This methylation could up- regulate or down-regulate corresponding gene expressions and modify related phenotypes. DNA methylation increases with aging and could be related to the late expression of some forms of mental disease. The objective of this study was to evaluate the association between anxiety disorders and/or depression in older women and DNA methylation for four genes related to anxiety or depression. Methods: Women aged 65 and older with (n = 19) or without (n = 24) anxiety disorders and/or major depressive episode (DSM-IV), were recruited. DNA methylation and single nucleotide variant (SNV) were evaluated from saliva, respectively by pyrosequencing and by PCR, for the following genes: brain-derived neurotrophic factor (BDNF; rs6265), oxytocin receptor (OXTR; rs53576), serotonin transporter (SLC6A4; rs25531), and apolipoprotein E (APOE; rs429358 and rs7412). Results: A greater BDNF DNA methylation was observed in subjects with anxiety/depression compared to control group subjects (Mean: 2.92 SD ± 0.74 vs. 2.34 ± 0.42; p= 0.0026). This difference was more pronounced in subjects carrying the BDNF rs6265 CT genotype (2.99 ± 0.41 vs. 2.27 ± 0.26; p= 0.0006) than those carrying the CC genotype (p= 0.0332); no subjects with the TT genotype were observed. For OXTR, a greater DNA methylation was observed in subjects with anxiety/depression, but only for those carrying the AA genotype of the OXTR rs53576 SNV, more particularly at one out of the seven CpGs studied (7.01 ± 0.94 vs. 4.44 ± 1.11; p= 0.0063). No significant differences were observed for APOE and SLC6A4. Conclusion: These results suggest that DNA methylation in interaction with SNV variations in BDNF and OXTR, are associated with the occurrence of anxiety/depression in older women.

Performance on spatial working memory tasks after dorsal or ventral hippocampal lesions and adjacent damage to the subiculum.

Rats with excitotoxic lesions of the dorsal or ventral hippocampus and control rats were trained on 2 spatial working memory tasks: the standard version of the radial maze with 8 baited arms and the non-matching-to-place procedure in the T maze. Dorsal lesions produced deficits in both tasks, whereas ventral lesions did not affect learning in either of them. A volumetric analysis of subicular damage showed that dorsal hippocampal lesions caused a deficit in the non-matching-to-place only when accompanied by damage to the dorsal subiculum; on the other hand, lesions to the dorsal hippocampus impaired performance in the radial-arm maze regardless of the extent of subicular damage.

Anxiety disorders, depressive episodes and cognitive impairment no dementia in community-dwelling older men and women.

Anxiety symptoms are highly prevalent in elders with mild cognitive disorders, but little is known about the associations of specific anxiety disorders to mild cognitive disorders.

Contributions of the dorsal hippocampus and the dorsal subiculum to processing of idiothetic information and spatial memory

It is well established that the dorsal hippocampal formation is crucial for spatial memory in rats. However, little is known about the distinct functions of the dorsal hippocampus and the dorsal subiculum. To examine the role of the dorsal hippocampus and the dorsal subiculum, Long-Evans rats with excitotoxic lesions (NMDA) of the dorsal hippocampus (DH), the dorsal subiculum (DS), or both (DHDS), and controls were trained on a nonmatching-to-place task. Then, to identify the strategy used by each group, they were tested on the same task in the dark with the T-maze being rotated between the sample and the test runs. In the light, rats with combined lesions were impaired. In the dark, groups DH, DS, and controls performed near chance level except in trials without rotation, suggesting the use of a sense of direction. The same rats were trained on a radial-arm maze task. In the light, where proximal visual cues were accessible, combined lesions affected performance whereas in the dark, it was impaired by all lesions. This experiment demonstrated that the dorsal subiculum and the dorsal hippocampus play a crucial role in processing idiothetic information and/or in maintenance of this information in memory.

Normative data for subcortical regional volumes over the lifetime of the adult human brain.

Normative data for volumetric estimates of brain structures are necessary to adequately assess brain volume alterations in individuals with suspected neurological or psychiatric conditions. Although many studies have described age and sex effects in healthy individuals for brain morphometry assessed via magnetic resonance imaging, proper normative values allowing to quantify potential brain abnormalities are needed. We developed norms for volumetric estimates of subcortical brain regions based on cross-sectional magnetic resonance scans from 2790 healthy individuals aged 18 to 94years using 23 samples provided by 21 independent research groups. The segmentation was conducted using FreeSurfer, a widely used and freely available automated segmentation software. Models predicting subcortical regional volumes of each hemisphere were produced including age, sex, estimated total intracranial volume (eTIV), scanner manufacturer, magnetic field strength, and interactions as predictors. The mean explained variance by the models was 48%. For most regions, age, sex and eTIV predicted most of the explained variance while manufacturer, magnetic field strength and interactions predicted a limited amount. Estimates of the expected volumes of an individual based on its characteristics and the scanner characteristics can be obtained using derived formulas. For a new individual, significance test for volume abnormality, effect size and estimated percentage of the normative population with a smaller volume can be obtained. Normative values were validated in independent samples of healthy adults and in adults with Alzheimers disease and schizophrenia.

Norms and associated factors of the STAI-Y State anxiety inventory in older adults: results from the PAQUID study.

BACKGROUND The latest version of the State-Trait Anxiety Inventory (STAI-Y) is commonly used in older adults, even though this anxiety scale was developed in and for young adults. Norms and associated factors of the STAI-Y are lacking for older adults in the general population. The objectives of the present study were to produce norms on the STAI-Y State scale for older adults using a large sample of older adults selected from a general population and to examine the sociodemographic and health-related factors associated with the STAI-Y State score. METHODS 993 community-dwelling individuals aged 66 years and over from the PAQUID study were evaluated at home by a psychologist for the following variables: age, education, marital status, proximity of relatives, self-assessment of income sufficiency, occupation during active life, depressive symptomatology, objective and subjective health, objective and subjective cognitive functioning, adverse life events, activities of daily living, drug use, and cigarette consumption. RESULTS Norms were stratified for age, sex, and education and were produced separately for older adults with and without depressive symptomatology. Multivariate analyses revealed that younger age (66-79 years), female sex, lower education, perception of income insufficiency, depressive symptomatology, poor subjective health, subjective cognitive complaints, psychotropic drugs use, and recent adverse life events were independently associated with higher STAI-Y State score. CONCLUSIONS This study provides norms for the STAI-Y State anxiety inventory in a general population of older adults and indicates the specific factors linked with state anxiety. Such factors should be taken into account by clinicians in order to better understand state anxiety in older adults.