Effects of weather and season on human brain volume

We present an exploratory cross-sectional analysis of the effect of season and weather on Freesurfer-derived brain volumes from a sample of 3,279 healthy individuals collected on two MRI scanners in Hartford, CT, USA over a 15 year period. Weather and seasonal effects were analyzed using a single linear regression model with age, sex, motion, scan sequence, time-of-day, month of the year, and the deviation from average barometric pressure, air temperature, and humidity, as covariates. FDR correction for multiple comparisons was applied to groups of non-overlapping ROIs. Significant negative relationships were found between the left- and right- cerebellum cortex and pressure (t = -2.25, p = 0.049; t = -2.771, p = 0.017). Significant positive relationships were found between left- and right- cerebellum cortex and white matter between the comparisons of January/June and January/September. Significant negative relationships were found between several subcortical ROIs for the summer months compared to January. An opposing effect was observed between the supra- and infra-tentorium, with opposite effect directions in winter and summer. Cohen’s d effect sizes from monthly comparisons were similar to those reported in recent psychiatric big-data publications, raising the possibility that seasonal changes and weather may be confounds in large cohort studies. Additionally, changes in brain volume due to natural environmental variation have not been reported before and may have implications for weather-related and seasonal ailments.

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Effects of Weather and Season on Human Brain Volume

10.1101/2020.07.07.191239 ◽

2020 ◽

Author(s):

Gregory A. Book ◽

Shashwath A. Meda ◽

Ronald Janssen ◽

Alecia D. Dager ◽

Andrew Poppe ◽

...

Keyword(s):

Brain Volume ◽

Barometric Pressure ◽

Time Of Day ◽

Seasonal Effects ◽

Cross Sectional ◽

Brain Volumes ◽

Left And Right ◽

Sectional Analysis ◽

Negative Relationships ◽

Opposing Effect

AbstractWe present an exploratory cross-sectional analysis of the effect of season and weather on Freesurfer-derived brain volumes from a sample of 3,279 healthy individuals collected on two MRI scanners in Hartford, CT, USA over a 15 year period. Weather and seasonal effects were analyzed using a single linear regression model with age, sex, motion, scan sequence, time-of-day, month of the year, and the deviation from average barometric pressure, air temperature, and humidity, as covariates. FDR correction for multiple comparisons was applied to groups of non-overlapping ROIs. Significant negative relationships were found between the left- and right-cerebellum cortex and pressure (t = −2.25, p = 0.049; t = −2.771, p = 0.017). Significant positive relationships were found between left- and right-cerebellum cortex and white matter between the comparisons of January/June and January/September. Significant negative relationships were found between several subcortical ROIs for the summer months compared to January. An opposing effect was observed between the supra- and infra-tentorium, with opposite effect directions in winter and summer. Cohen’s d effect sizes from monthly comparisons were similar to those reported in recent psychiatric big-data publications, raising the possibility that seasonal changes and weather may be confounds in large cohort studies. Additionally, changes in brain volume due to natural environmental variation have not been reported before and may have implications for weather-related and seasonal ailments.

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Atrial Fibrillation and Brain Magnetic Resonance Imaging Abnormalities

Stroke ◽

10.1161/strokeaha.118.024143 ◽

2019 ◽

Vol 50 (4) ◽

pp. 783-788 ◽

Cited By ~ 6

Author(s):

Jeremy P. Berman ◽

Faye L. Norby ◽

Thomas Mosley ◽

Elsayed Z. Soliman ◽

Rebecca F. Gottesman ◽

...

Keyword(s):

Magnetic Resonance Imaging ◽

Brain Volume ◽

Brain Mri ◽

Brain Magnetic Resonance Imaging ◽

White Matter Hyperintensity ◽

Resonance Imaging ◽

Total Brain Volume ◽

Cross Sectional ◽

Total Brain ◽

Sectional Analysis

Background and Purpose— Atrial fibrillation (AF) is associated with dementia independent of clinical stroke. The mechanisms underlying this association remain unclear. In a community-based cohort, the ARIC study (Atherosclerosis Risk in Communities), we evaluated (1) the longitudinal association of incident AF and (2) the cross-sectional association of prevalent AF with brain magnetic resonance imaging (MRI) abnormalities. Methods— The longitudinal analysis included 963 participants (mean age, 73±4.4 years; 62% women; 51% black) without prevalent stroke or AF who underwent a brain MRI in 1993 to 1995 and a second MRI in 2004 to 2006 (mean, 10.6±0.8 years). Outcomes included subclinical cerebral infarctions, sulcal size, ventricular size, and, for the cross-sectional analysis, white matter hyperintensity volume and total brain volume. Results— In the longitudinal analysis, 29 (3.0%) participants developed AF after the first brain MRI. Those who developed AF had higher odds of increase in subclinical cerebral infarctions (odds ratio [OR], 3.08; 95% CI, 1.39–6.83), worsening sulcal grade (OR, 3.56; 95% CI, 1.04–12.2), and worsening ventricular grade (OR, 9.34; 95% CI, 1.24–70.2). In cross-sectional analysis, of 969 participants, 35 (3.6%) had prevalent AF at the time of the 2004 to 2006 MRI scan. Those with AF had greater odds of higher sulcal (OR, 3.9; 95% CI, 1.7–9.1) and ventricular grade (OR, 2.4; 95% CI, 1.0–5.7) after multivariable adjustment and no difference in white matter hyperintensity or total brain volume. Conclusions— AF is independently associated with increase in subclinical cerebral infarction and worsening sulcal and ventricular grade—morphological changes associated with aging and dementia. More research is needed to define the mechanisms underlying AF-related neurodegeneration.

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FALLERS AND CORTICAL BRAIN VOLUMES: CROSS-SECTIONAL ANALYSIS IN COGNITIVELY HEALTHY OLDER ADULTS

Innovation in Aging ◽

10.1093/geroni/igx004.3838 ◽

2017 ◽

Vol 1 (suppl_1) ◽

pp. 1050-1050

Author(s):

O. Beauchet ◽

G. Allali ◽

J. Verghese

Keyword(s):

Older Adults ◽

Cross Sectional ◽

Brain Volumes ◽

Healthy Older Adults ◽

Cross Sectional Analysis ◽

Sectional Analysis

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Brain volume in first-episode schizophrenia

The British Journal of Psychiatry ◽

10.1192/bjp.188.6.510 ◽

2006 ◽

Vol 188 (6) ◽

pp. 510-518 ◽

Cited By ~ 515

Author(s):

R. Grant Steen ◽

Courtney Mull ◽

Robert Mcclure ◽

Robert M. Hamer ◽

Jeffrey A. Lieberman

Keyword(s):

Brain Volume ◽

Limit Of Detection ◽

Meta Analysis ◽

First Episode ◽

Psychotic Episode ◽

Healthy Controls ◽

Brain Abnormalities ◽

Cross Sectional ◽

Brain Volumes ◽

First Psychotic Episode

BackgroundStudies of people with schizophrenia assessed using magnetic resonance imaging (MRI) usually include patients with first-episode and chronic disease, yet brain abnormalities may be limited to those with chronic schizophrenia.AimsTo determine whether patients with a first episode of schizophrenia have characteristic brain abnormalities.MethodSystematic review and meta-analysis of 66 papers comparing brain volume in patients with a first psychotic episode with volume in healthy controls.ResultsAtotal of 52 cross-sectional studies included 1424 patients with a first psychotic episode; 16 longitudinal studies included 465 such patients. Meta-analysis suggests that whole brain and hippocampal volume are reduced (both P < 0.0001) and that ventricular volume is increased (P < 0.0001) in these patients relative to healthy controls.ConclusionsAverage volumetric changes are close to the limit of detection by MRI methods. It remains to be determined whether schizophrenia is a neurodegenerative process that begins at about the time of symptom onset, or whether it is better characterised as a neurodevelopmental process that produces abnormal brain volumes at an early age.

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Is Distance to the Nearest Registered Public Automated Defibrillator Associated with the Probability of Bystander Shock for Victims of Out-of-Hospital Cardiac Arrest?

Prehospital and Disaster Medicine ◽

10.1017/s1049023x18000080 ◽

2018 ◽

Vol 33 (2) ◽

pp. 153-159 ◽

Cited By ~ 5

Author(s):

Joel Neves Briard ◽

Luc de Montigny ◽

Dave Ross ◽

François de Champlain ◽

Eli Segal

Keyword(s):

Cardiac Arrest ◽

Urban Areas ◽

Prehospital Care ◽

Time Of Day ◽

Publication Type ◽

Cross Sectional ◽

Automated External Defibrillators ◽

Life Saving ◽

Sectional Analysis ◽

Hospital Cardiac Arrest

AbstractIntroductionRapid access to defibrillation is a key element in the management of out-of-hospital cardiac arrests (OHCAs). Public automated external defibrillators (PAEDs) are becoming increasingly available, but little information exists regarding the relation between the proximity to the arrest and their usage in urban areas.MethodsThis study is a retrospective, observational, cross-sectional analysis of non-traumatic OHCA during a 24-month period in the greater Montreal area (Quebec, Canada). Using logistic regression, bystander shock odds are described with regards to distance from the OHCA scene to the nearest PAED, adjusted for prehospital care arrival delay and time of day, and stratifying for type of location.ResultsOut of a total of 2,443 OHCA victims identified, 77 (3%) received bystander PAED shock, 622 (26%) occurred out-of-home, and 743 (30%) occurred during business hours. When controlling for time (business hours versus other hours) and minimum response delay for prehospital care arrival, a marginal negative association was found between bystander shock and distance to the nearest PAED in logged meters (aOR=0.80; CI, 0.64-0.99) for out-of-home cardiac arrests. No significant association was found between distance and bystander shock for at-home arrests. Out-of-home victims had significantly higher odds of receiving bystander shock up to 175 meters of distance to a PAED inclusively (aOR=2.52; CI, 1.07-5.89).ConclusionFor out-of-home cardiac arrests, proximity to a PAED was associated with bystander shock in the greater Montreal area. Strategies aiming to increase accessibility and use of these life-saving devices could further expand this advantage by assisting bystanders in rapidly locating nearby PAEDs.Neves BriardJ, de MontignyL, RossD, de ChamplainF, SegalE. Is distance to the nearest registered public automated defibrillator associated with the probability of bystander shock for victims of out-of-hospital cardiac arrest?Prehosp Disaster Med. 2018;33(2):153–159.

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The Relationship Between Time of Day of Physical Activity and Obesity in Older Women

Journal of Physical Activity and Health ◽

10.1123/jpah.2015-0152 ◽

2016 ◽

Vol 13 (4) ◽

pp. 416-418 ◽

Cited By ~ 15

Author(s):

Andrea K. Chomistek ◽

Eric J. Shiroma ◽

I-Min Lee

Keyword(s):

Physical Activity ◽

Weight Control ◽

Time Of Day ◽

Health Study ◽

Healthy Weight ◽

Cross Sectional ◽

Important Health ◽

Novel Strategy ◽

Study Participants ◽

Sectional Analysis

Background:Physical activity is important for maintaining healthy weight. The time of day when exercise is performed—a highly discretionary aspect of behavior—may impact weight control, but evidence is limited. Thus, we examined the association between the timing of physical activity and obesity risk in women.Methods:A cross-sectional analysis was conducted among 7157 Women’s Health Study participants who participated in an ancillary study begun in 2011 that is measuring physical activity using accelerometers. The exposure was percentage of total accelerometer counts accumulated before 12:00 noon and the outcome was obesity.Results:Mean (±SD) BMI among participants was 26.1 (±4.9) kg/m2 and 1322 women were obese. The mean activity counts per day was 203,870 (±95,811) of which a mean 47.1% (±11.5%) were recorded in the morning. In multivariable-adjusted models, women who recorded < 39% (lowest quartile) of accelerometer counts before 12:00 noon had a 26% higher odds of being obese, compared with those recording ≥ 54% (highest quartile) of counts before noon (Ptrend = 0.02).Conclusions:These study findings—that women who are less active during morning hours may be at higher risk of obesity—if confirmed can provide a novel strategy to help combat the important health problem of obesity.

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Mediterranean-type diet and brain structural change from 73 to 76 years in a Scottish cohort

Neurology ◽

10.1212/wnl.0000000000003559 ◽

2017 ◽

Vol 88 (5) ◽

pp. 449-455 ◽

Cited By ~ 54

Author(s):

Michelle Luciano ◽

Janie Corley ◽

Simon R. Cox ◽

Maria C. Valdés Hernández ◽

Leone C.A. Craig ◽

...

Keyword(s):

Cortical Thickness ◽

Gray Matter ◽

Brain Volume ◽

Gray Matter Volume ◽

Brain Mri ◽

Total Brain Volume ◽

Cross Sectional ◽

Brain Volumes ◽

Total Brain ◽

Lower Adherence

Objective:To assess the association between Mediterranean-type diet (MeDi) and change in brain MRI volumetric measures and mean cortical thickness across a 3-year period in older age (73–76 years).Methods:We focused on 2 longitudinal brain volumes (total and gray matter; n = 401 and 398, respectively) plus a longitudinal measurement of cortical thickness (n = 323), for which the previous cross-sectional evidence of an association with the MeDi was strongest. Adherence to the MeDi was calculated from data gathered from a food frequency questionnaire at age 70, 3 years prior to the baseline imaging data collection.Results:In regression models adjusting for relevant demographic and physical health indicators, we found that lower adherence to the MeDi was associated with greater 3-year reduction in total brain volume (explaining 0.5% of variance, p < 0.05). This effect was half the size of the largest covariate effect (i.e., age). Cross-sectional associations between MeDi and baseline MRI measures in 562 participants were not significant. Targeted analyses of meat and fish consumption did not replicate previous associations with total brain volume or total gray matter volume.Conclusions:Lower adherence to the MeDi in an older Scottish cohort is predictive of total brain atrophy over a 3-year interval. Fish and meat consumption does not drive this change, suggesting that other components of the MeDi or, possibly, all of its components in combination are responsible for the association.

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Ultramicrotomy as a Technique for Materials Specimen Preparation

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100135745 ◽

1990 ◽

Vol 48 (2) ◽

pp. 428-429

Author(s):

S.R. Glanvill

Keyword(s):

Materials Science ◽

Structural Information ◽

Specimen Preparation ◽

Preparation Technique ◽

Cross Sectional ◽

Surfaces And Interfaces ◽

Beam Analysis ◽

Flat Embedding ◽

20 Nm ◽

Sectional Analysis

This paper summarizes the application of ultramicrotomy as a specimen preparation technique for some of the Materials Science applications encountered over the past two years. Specimens 20 nm thick by hundreds of μm lateral dimension are readily prepared for electron beam analysis. Materials examined include metals, plastics, ceramics, superconductors, glassy carbons and semiconductors. We have obtain chemical and structural information from these materials using HRTEM, CBED, EDX and EELS analysis. This technique has enabled cross-sectional analysis of surfaces and interfaces of engineering materials and solid state electronic devices, as well as interdiffusion studies across adjacent layers.Samples are embedded in flat embedding moulds with Epon 812 epoxy resin / Methyl Nadic Anhydride mixture, using DY064 accelerator to promote the reaction. The embedded material is vacuum processed to remove trapped air bubbles, thereby improving the strength and sectioning qualities of the cured block. The resin mixture is cured at 60 °C for a period of 80 hr and left to equilibrate at room temperature.

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Twitter Usage Using Common Reference to Tinnitus

American Journal of Audiology ◽

10.1044/2020_aja-19-00055 ◽

2020 ◽

Vol 29 (2) ◽

pp. 206-217

Author(s):

Jianyuan Ni ◽

Monica L. Bellon-Harn ◽

Jiang Zhang ◽

Yueqing Li ◽

Vinaya Manchaiah

Keyword(s):

Nonprofit Organizations ◽

Temporal Trends ◽

Temporal Analysis ◽

Cross Sectional ◽

For Profit ◽

Common Reference ◽

Personal Experiences ◽

Twitter Users ◽

Sectional Analysis ◽

Share Information

Objective The objective of the study was to examine specific patterns of Twitter usage using common reference to tinnitus. Method The study used cross-sectional analysis of data generated from Twitter data. Twitter content, language, reach, users, accounts, temporal trends, and social networks were examined. Results Around 70,000 tweets were identified and analyzed from May to October 2018. Of the 100 most active Twitter accounts, organizations owned 52%, individuals owned 44%, and 4% of the accounts were unknown. Commercial/for-profit and nonprofit organizations were the most common organization account owners (i.e., 26% and 16%, respectively). Seven unique tweets were identified with a reach of over 400 Twitter users. The greatest reach exceeded 2,000 users. Temporal analysis identified retweet outliers (> 200 retweets per hour) that corresponded to a widely publicized event involving the response of a Twitter user to another user's joke. Content analysis indicated that Twitter is a platform that primarily functions to advocate, share personal experiences, or share information about management of tinnitus rather than to provide social support and build relationships. Conclusions Twitter accounts owned by organizations outnumbered individual accounts, and commercial/for-profit user accounts were the most frequently active organization account type. Analyses of social media use can be helpful in discovering issues of interest to the tinnitus community as well as determining which users and organizations are dominating social network conversations.

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