Reliability of multi-site UK Biobank MRI brain phenotypes for the assessment of neuropsychiatric complications of SARS-CoV-2 infection: The COVID-CNS travelling heads study.

INTRODUCTION: Magnetic resonance imaging (MRI) of the brain could be a key diagnostic and research tool for understanding the neuropsychiatric complications of COVID-19. For maximum impact, multi-modal MRI protocols will be needed to measure the effects of SARS-CoV-2 infection on the brain by diverse potentially pathogenic mechanisms, and with high reliability across multiple sites and scanner manufacturers. Here we describe the development of such a protocol, based upon the UK Biobank, and its validation with a travelling heads study. A multi-modal brain MRI protocol comprising sequences for T1-weighted MRI, T2-FLAIR, diffusion MRI (dMRI), resting-state functional MRI (fMRI), susceptibility-weighted imaging (swMRI), and arterial spin labelling (ASL), was defined in close approximation to prior UK Biobank (UKB) and C-MORE protocols for Siemens 3T systems. We iteratively defined a comparable set of sequences for General Electric (GE) 3T systems. To assess multi-site feasibility and between-site variability of this protocol, N = 8 healthy participants were each scanned at 4 UK sites: 3 using Siemens PRISMA scanners (Cambridge, Liverpool, Oxford) and 1 using a GE scanner (King's College London). Over 2,000 Imaging Derived Phenotypes (IDPs), measuring both data quality and regional image properties of interest, were automatically estimated by customised UKB image processing pipelines (S2 File). Components of variance and intra-class correlations (ICCs) were estimated for each IDP by linear mixed effects models and benchmarked by comparison to repeated measurements of the same IDPs from UKB participants. Intra-class correlations for many IDPs indicated good-to-excellent between-site reliability. Considering only data from the Siemens sites, between-site reliability generally matched the high levels of test-retest reliability of the same IDPs estimated in repeated, within-site, within-subject scans from UK Biobank. Inclusion of the GE site resulted in good-to-excellent reliability for many IDPs, although there were significant between-site differences in mean and scaling, and reduced ICCs, for some classes of IDP, especially T1 contrast and some dMRI-derived measures. We also identified high reliability of quantitative susceptibility mapping (QSM) IDPs derived from swMRI images, multi-network ICA-based IDPs from resting-state fMRI, and olfactory bulb structure IDPs from T1, T2-FLAIR and dMRI data. CONCLUSION: These results give confidence that large, multi-site MRI datasets can be collected reliably at different sites across the diverse range of MRI modalities and IDPs that could be mechanistically informative in COVID brain research. We discuss limitations of the study and strategies for further harmonisation of data collected from sites using scanners supplied by different manufacturers. These acquisition and analysis protocols are now in use for MRI assessments of post-COVID patients (N = 700) as part of the ongoing COVID-CNS study.

Ethnic-specific suggestions for physical activity based on existing recreational physical activity preferences of New Zealand women.

OBJECTIVES: Recreational physical activities of New Zealand women were examined to develop ethnic-specific suggestions encouraging physical activity (PA) participation as a targeted approach to reduce obesity rates among different groups. METHODS: Healthy Maori, Pacific and European women (n=331; 16-45 years of age) completed an online Recent Physical Activity Questionnaire to assess recreational PA and adherence to PA guidelines. Existing PA preferences were tailored to make ethnic-specific suggestions aimed at increasing PA participation. RESULTS: Achievement of PA guidelines was: Maori 74%; Pacific 60%; European 70%. Highest participation across all women was for walking (Maori 72%, Pacific 60%, European 83%), followed by floor exercise (Maori 54%, Pacific 37%, European 56%). Gym-type activities (e.g. weights, aerobics) and jogging were also common across ethnic groups. Group/team activities (dance, netball, touch football) were among the top 10 activities for Maori and Pacific, but not European women. CONCLUSION: Obesity rates among specific ethnic groups of New Zealand women might be reduced by promoting activities that are: family/whanau-oriented (netball, touch), community-linked (hula, dance) and outdoor-based. Implications for public health: Tailoring existing PA preferences to develop ethnic-specific sets of activity suggestions could be important avenues to increase PA participation, improving the PA habits and subsequent health of New Zealand women and their communities.

Exploring the challenges in obtaining physical activity data from women using hip-worn accelerometers.

Quality objective physical activity data are required to inform physical activity-based health improvement initiatives, however, various challenges undermine acquisition of such data. We examined the efficacy and challenges of a hip-worn accelerometry protocol in women. Specific objectives included determining accelerometer-wear-compliance rates and understanding the barriers and acceptability of wearing accelerometers. Healthy New Zealand women (n = 406) of three ethnicities (Maori (indigenous New Zealander), Pacific, European) aged 16-45 years (30.9 ± 8.7 y) wore hip-mounted Actigraph wGT3X+ accelerometers for 7 consecutive days under a 24-h wear protocol. Post hoc, a sub-sample (n = 45; age: 29.4 ± 9.0 y) was interviewed to investigate comfort/convenience and burdens of accelerometer-wear. Wear-compliance (≥10 h/day, ≥4 day) was 86%. European women returned more valid data (92.7%, p < .04) than Pacific (73.0%) or Maori women (82.1%). Twenty-two participants (5.4%) had completely missing data; 13 due to lost accelerometers. Burden of accelerometer-wear was greatest during sleeping (66.7%) due to discomfort. Embarrassment of accelerometer visibility through clothing and consequent restricted clothing choices caused high burden in social settings (45.2%). Discomfort during sleeping, embarrassment due to perceived appearance in social settings and ethnicity are key factors affecting the efficacy of collecting physical activity data from women using hip-worn accelerometers. Refining accelerometer design to reduce size and subsequently participant burden should improve acceptability and wear-compliance. Increasing overall participant compliance by reducing burden and ensuring appropriate understanding of study aims and relevance should reduce attrition and improve wear-compliance and data quality when collecting accelerometry data from women of different ethnicities.

Predictors and risks of body fat profiles in young New Zealand European, Maori and Pacific women: study protocol for the women's EXPLORE study.

BACKGROUND: Body mass index (BMI) (kg/m(2)) is used internationally to assess body mass or adiposity. However, BMI does not discriminate body fat content or distribution and may vary among ethnicities. Many women with normal BMI are considered healthy, but may have an unidentified "hidden fat" profile associated with higher metabolic disease risk. If only BMI is used to indicate healthy body size, it may fail to predict underlying risks of diseases of lifestyle among population subgroups with normal BMI and different adiposity levels or distributions. Higher body fat levels are often attributed to excessive dietary intake and/or inadequate physical activity. These environmental influences regulate genes and proteins that alter energy expenditure/storage. Micro ribonucleic acid (miRNAs) can influence these genes and proteins, are sensitive to diet and exercise and may influence the varied metabolic responses observed between individuals. The study aims are to investigate associations between different body fat profiles and metabolic disease risk; dietary and physical activity patterns as predictors of body fat profiles; and whether these risk factors are associated with the expression of microRNAs related to energy expenditure or fat storage in young New Zealand women. Given the rising prevalence of obesity globally, this research will address a unique gap of knowledge in obesity research. METHODS/DESIGN: A cross-sectional design to investigate 675 NZ European, Maori, and Pacific women aged 16-45 years. Women are classified into three main body fat profiles (n = 225 per ethnicity; n = 75 per body fat profile): 1) normal BMI, normal body fat percentage (BF%); 2) normal BMI, high BF%; 3) high BMI, high BF%. Regional body composition, biomarkers of metabolic disease risk (i.e. fasting insulin, glucose, HbA1c, lipids), inflammation (i.e. IL-6, TNF-alpha, hs-CRP), associations between lifestyle factors (i.e. dietary intake, physical activity, taste perceptions) and microRNA expression will be investigated. DISCUSSION: This research targets post-menarcheal, premenopausal women, potentially exhibiting lifestyle behaviours resulting in excess body fat affecting metabolic health. These behaviours may be characterised by specific patterns of microRNA expression that will be explored in terms of tailored solutions specific to body fat profile groups and ethnicities. TRIAL REGISTRATION: ACTRN12613000714785.