Perceptions of diabetes risk and prevention in Nairobi, Kenya: A qualitative and theory of change development study.

BACKGROUND: Type 2 diabetes is increasing in Kenya, especially in urban settings, and prevention interventions based on local evidence and context are urgently needed. Therefore, this study aimed to explore diabetes risk and co-create a diabetes prevention theory of change in two socioeconomically distinct communities to inform future diabetes prevention interventions. METHODS: In-depth interviews were conducted with middle-aged residents in two communities in Nairobi (one low-income (n = 15), one middle-income (n = 14)), and thematically analysed. The theory of change for diabetes prevention was informed by analysis of the in-depth interviews and the Behaviour Change Wheel framework, and reviewed by a sub-set (n = 13) of interviewees. RESULTS: The key factors that influenced diabetes preventive practices in both communities included knowledge and skills for diabetes prevention, understanding of the benefits/consequences of (un)healthy lifestyle, social influences (e.g., upbringing, societal perceptions), and environmental contexts (e.g., access to (un)healthy foods and physical activity facilities). The proposed strategies for diabetes prevention included: increasing knowledge and understanding about diabetes risk and preventive measures particularly in the low-income community; supporting lifestyle modification (e.g., upskilling, goal setting, action planning) in both communities; identifying people at high risk of diabetes through screening in both communities; and creating social and physical environments for lifestyle modification (e.g., positive social influences on healthy living, access to healthy foods and physical activity infrastructure) particularly in the low-income community. Residents from both communities agreed that the strategies were broadly feasible for diabetes prevention but proposed the addition of door-to-door campaigns and community theatre for health education. However, residents from the low-income community were concerned about the lack of government prioritisation for implementing population-level interventions, e.g., improving access to healthy foods and physical activity facilities/infrastructure. CONCLUSION: Diabetes prevention initiatives in Kenya should involve multicomponent interventions for lifestyle modification including increasing education and upskilling at individual level; promoting social and physical environments that support healthy living at population level; and are particularly needed in low-income communities.

Effects of increasing light versus moderate-to-vigorous physical activity on cardiometabolic health in Chinese adults with obesity.

Increasing daily physical activity (PA) is a practical way to decrease the risk of cardiometabolic diseases, while the studies on exercise intensity remain limited. The purpose of the present study was to compare the effects of increasing light PA (LPA) or moderate-to-vigorous PA (MVPA) for 12 weeks on cardiometabolic markers in Chinese adults with obesity. Fifty-three adults were randomly assigned to the 1) control group, 2) LPA group, and 3) MVPA group in free-living settings. The intervention effects on body composition, cardiorespiratory fitness, and cardiometabolic biomarkers were analysed using a generalized estimated equation model adjusted for baseline values and potential confounders. Compared with the control group, the MVPA group showed improvements in body composition, lipids, C-peptide, monocyte chemoattractant protein-1 (MCP-1), interleukin-8, leptin, and E-selectin. A favourable change in triglycerides and E-selectin were observed in the LPA group when compared to the control group. Lastly, improvements in waist circumference, C-reactive protein, and MCP-1 were observed in the MVPA group when compared to those in the LPA group. Although increasing both LPA and MVPA improved certain cardiometabolic biomarkers, the latter may have more benefits. These findings imply that MVPA may reduce cardiometabolic disease risk more effectively than LPA, especially in Chinese adults with obesity.

Social connection and mortality in UK Biobank: a prospective cohort analysis.

BACKGROUND: Components of social connection are associated with mortality, but research examining their independent and combined effects in the same dataset is lacking. This study aimed to examine the independent and combined associations between functional and structural components of social connection and mortality. METHODS: Analysis of 458,146 participants with full data from the UK Biobank cohort linked to mortality registers. Social connection was assessed using two functional (frequency of ability to confide in someone close and often feeling lonely) and three structural (frequency of friends/family visits, weekly group activities, and living alone) component measures. Cox proportional hazard models were used to examine the associations with all-cause and cardiovascular disease (CVD) mortality. RESULTS: Over a median of 12.6 years (IQR 11.9-13.3) follow-up, 33,135 (7.2%) participants died, including 5112 (1.1%) CVD deaths. All social connection measures were independently associated with both outcomes. Friends/family visit frequencies < monthly were associated with a higher risk of mortality indicating a threshold effect. There were interactions between living alone and friends/family visits and between living alone and weekly group activity. For example, compared with daily friends/family visits-not living alone, there was higher all-cause mortality for daily visits-living alone (HR 1.19 [95% CI 1.12-1.26]), for never having visits-not living alone (1.33 [1.22-1.46]), and for never having visits-living alone (1.77 [1.61-1.95]). Never having friends/family visits whilst living alone potentially counteracted benefits from other components as mortality risks were highest for those reporting both never having visits and living alone regardless of weekly group activity or functional components. When all measures were combined into overall functional and structural components, there was an interaction between components: compared with participants defined as not isolated by both components, those considered isolated by both components had higher CVD mortality (HR 1.63 [1.51-1.76]) than each component alone (functional isolation 1.17 [1.06-1.29]; structural isolation 1.27 [1.18-1.36]). CONCLUSIONS: This work suggests (1) a potential threshold effect for friends/family visits, (2) that those who live alone with additional concurrent markers of structural isolation may represent a high-risk population, (3) that beneficial associations for some types of social connection might not be felt when other types of social connection are absent, and (4) considering both functional and structural components of social connection may help to identify the most isolated in society.

The roles of DGAT1 and DGAT2 in human myotubes are dependent on donor patho-physiological background.

The roles of DGAT1 and DGAT2 in lipid metabolism and insulin responsiveness of human skeletal muscle were studied using cryosections and myotubes prepared from muscle biopsies from control, athlete, and impaired glucose regulation (IGR) cohorts of men. The previously observed increases in intramuscular triacylglycerol (IMTG) in athletes and IGR were shown to be related to an increase in lipid droplet (LD) area in type I fibers in athletes but, conversely, in type II fibers in IGR subjects. Specific inhibition of both diacylglycerol acyltransferase (DGAT) 1 and 2 decreased fatty acid (FA) uptake by myotubes, whereas only DGAT2 inhibition also decreased fatty acid oxidation. Fatty acid uptake in myotubes was negatively correlated with the lactate thresholds of the respective donors. DGAT2 inhibition lowered acetate uptake and oxidation in myotubes from all cohorts whereas DGAT1 inhibition had no effect. A positive correlation between acetate oxidation in myotubes and resting metabolic rate (RMR) from fatty acid oxidation in vivo was observed. Myotubes from athletes and IGR had higher rates of de novo lipogenesis from acetate that were normalized by DGAT2 inhibition. Moreover, DGAT2 inhibition in myotubes also resulted in increased insulin-induced Akt phosphorylation. The differential effects of DGAT1 and DGAT2 inhibition suggest that the specialized role of DGAT2 in esterifying nascent diacylglycerols and de novo synthesized FA is associated with synthesis of a pool of triacylglycerol, which upon hydrolysis results in effectors that promote mitochondrial fatty acid oxidation but decrease insulin signaling in skeletal muscle cells.

Benefits, risks, barriers, and facilitators to cycling: a narrative review.

There is large potential to increase cycling participation worldwide. Participation in cycling is associated with lower risk of mortality from any cause, and incidence of cardiovascular disease and type 2 diabetes, as well as positive mental health and well-being. The largest potential for health gains likely to come from increasing participation amongst those who do not currently cycle regularly, rather than encouraging those who already cycle regularly to cycle more. Replacing car journeys with cycling can lead to reductions in air pollution emissions and lower pollutant exposure to the general population. Important gaps and uncertainties in the existing evidence base include: the extent to which the health benefits associated with cycling participation are fully causal due to the observational nature of much of the existing evidence base; the real-world economic cost-benefits of pragmatic interventions to increase cycling participation; and the most effective (combination of) approaches to increase cycling participation. To address these uncertainties, large-scale, long-term randomised controlled trials are needed to: evaluate the effectiveness, and cost-effectiveness, of (combinations of) intervention approaches to induce sustained long-term increases in cycling participation in terms of increases in numbers of people cycling regularly and number of cycling journeys undertaken, across a range of population demographic groups; establish the effects of such interventions on relevant outcomes related to health and wellbeing, economic productivity and wider societal impacts; and provide more robust quantification of potential harms of increasing cycling participation, such as collision risks.

Brief bouts of device-measured intermittent lifestyle physical activity and its association with major adverse cardiovascular events and mortality in people who do not exercise: a prospective cohort study.

BACKGROUND: Guidelines emphasise the health benefits of bouts of physical activity of any duration. However, the associations of intermittent lifestyle physical activity accumulated through non-exercise with mortality and major adverse cardiovascular events (MACE) remain unclear. We aimed to examine the associations of bouts of moderate-to-vigorous intermittent lifestyle physical activity (MV-ILPA) and the proportion of vigorous activity contributing within these bouts with mortality and MACE. METHODS: In this prospective cohort study, we used data from the UK Biobank on adults who do not exercise (ie, those who did not report leisure-time exercise) who had wrist-worn accelerometry data available. Participants were followed up until Nov 30, 2022, with the outcome of interest of all-cause mortality obtained through linkage with NHS Digital of England and Wales, and the NHS Central Register and National Records of Scotland, and MACE obtained from inpatient hospitalisation data provided by the Hospital Episode Statistics for England, the Patient Episode Database for Wales, and the Scottish Morbidity Record for Scotland. MV-ILPA bouts were derived using a two-level Random Forest classifier and grouped as short (<1 min), medium (1 to <3 min; 3 to <5 min), and long (5 to <10 min). We further examined the dose-response relationship of the proportion of vigorous physical activity contributing to the MV-ILPA bout. FINDINGS: Between June 1, 2013, and Dec 23, 2015, 103 684 Biobank participants wore an accelerometer on their wrist. 25 241 adults (mean age 61·8 years [SD 7·6]), of whom 14 178 (56·2%) were women, were included in our analysis of all-cause mortality. During a mean follow-up duration of 7·9 years (SD 0·9), 824 MACE and 1111 deaths occurred. Compared with bouts of less than 1 min, mortality risk was lower for bouts of 1 min to less than 3 min (hazard ratio [HR] 0·66 [0·53-0·81]), 3 min to less than 5 min (HR 0·56 [0·46-0·69]), and 5 to less than 10 min (HR 0·48 [0·39-0·59]). Similarly, compared with bouts of less than 1 min, risk of MACE was lower for bouts of 1 min to less than 3 min (HR 0·71 [0·54-0·93]), 3 min to less than 5 min (0·62 [0·48-0·81]), and 5 min to less than 10 min (0·59 [0·46-0·76]). Short bouts (<1 min) were associated with lower MACE risk only when bouts were comprised of at least 15% vigorous activity. INTERPRETATION: Intermittent non-exercise physical activity was associated with lower mortality and MACE. Our results support the promotion of short intermittent bouts of non-exercise physical activity of moderate-to-vigorous intensity to improve longevity and cardiovascular health among adults who do not habitually exercise in their leisure time. FUNDING: Australian National Health, Medical Research Council, and Wellcome Trust.

Associations and predictive performance of 11 anthropometric measures with incident type 2 diabetes: A prospective cohort study from the UK Biobank.

OBJECTIVE: The study aim was to investigate associations of 11 anthropometric measures with incident type 2 diabetes and compare their predictive performance. METHODS: This prospective cohort study included 161,127 White European UK Biobank participants who were free of diabetes at baseline. Anthropometric measures included height, weight, BMI, A Body Shape Index, waist circumference, waist to hip ratio, waist to height ratio (WHtR), hip circumference, visceral adiposity index, hip index, and anthropometric risk index. The associations were examined using Cox proportional hazard models. The differences in C-index were used to compare predictive performance between BMI and other anthropometric measures. RESULTS: The median follow-up was 10.0 (interquartile range: 9.3-10.8) years, during which 6315 participants developed type 2 diabetes. All markers except height and hip index were positively associated with incident type 2 diabetes. The strongest associations were found for WHtR (hazard ratio per 1-SD increment: 2.27 [95% CI 2.19-2.35] in women; 1.96 [95% CI 1.90-2.01] in men). Compared with BMI, WHtR and anthropometric risk index had significantly better type 2 diabetes risk discrimination. CONCLUSIONS: Although most adiposity markers were associated with type 2 diabetes, the magnitude of the associations differed. WHtR had the strongest associations and predictive ability for type 2 diabetes and thus could be a more suitable marker for clinical use.

The effect of home-based resistance exercise training in people with type 2 diabetes: A randomized controlled trial.

AIMS: To evaluate the effects of pragmatic home-based resistance exercise training on glycated haemoglobin (HbA1c) as well as muscle strength and body composition in people with type 2 diabetes. MATERIALS AND METHODS: People with type 2 diabetes were randomized (1:1) to usual care or usual care plus home-based resistance exercise for 32 weeks. The changes in HbA1c, body composition, physical function, quality of life, continuous glucose monitoring and liver fat were compared by randomized group using linear regression. RESULTS: This study recruited 120 participants (female: n = 46 [38%], age 60.2 (9.4) years, BMI 31.1 (5.4) kg.m-2 ), 64 to intervention and 56 to usual care. Intention to treat analysis revealed no effect on HbA1c (difference in difference: -0.4 mmol/mol, 95% confidence interval [CI]: -3.26, 2.47; p = 0.78) but the intervention increased the number of push-ups (3.6 push-ups, 95% CI: 0.8, 6.4), arm lean mass (116 g, 95% CI: 6, 227) and leg lean mass (438 g, 95% CI 65, 810) and decreased liver fat (-1.27%, 95% CI -2.17, -0.38), with no differences in other outcomes. Per-protocol analysis revealed similar results. CONCLUSIONS: Home-based resistance exercise is unlikely to lower HbA1c in people with type 2 diabetes but may be of benefit for maintaining muscle mass and function and reducing liver fat.

Recommendations from Diabetes UK's 2022 diabetes and physical activity workshop.

AIMS: To describe the process and outputs of a workshop convened to identify key priorities for future research in the area of diabetes and physical activity and provide recommendations to researchers and research funders on how best to address them. METHODS: A 1-day research workshop was conducted, bringing together researchers, people living with diabetes, healthcare professionals, and members of staff from Diabetes UK to identify and prioritise recommendations for future research into physical activity and diabetes. RESULTS: Workshop attendees prioritised four key themes for further research: (i) better understanding of the physiology of exercise in all groups of people: in particular, what patient metabolic characteristics influence or predict the physiological response to physical activity, and the potential role of physical activity in beta cell preservation; (ii) designing physical activity interventions for maximum impact; (iii) promoting sustained physical activity across the life course; (iv) designing physical activity studies for groups with multiple long-term conditions. CONCLUSIONS: This paper outlines recommendations to address the current gaps in knowledge related to diabetes and physical activity and calls on the research community to develop applications in these areas and funders to consider how to stimulate research in these areas.

Dose-response relationship between device-measured physical activity and incident type 2 diabetes: findings from the UK Biobank prospective cohort study.

BACKGROUND: Most studies investigating the association between physical activity (PA) and the risk of type 2 diabetes are derived from self-reported questionnaires, with limited evidence using device-based measurements. Therefore, this study aimed to investigate the dose-response relationship between device-measured PA and incident type 2 diabetes. METHODS: This prospective cohort study included 40,431 participants of the UK Biobank. Wrist-worn accelerometers were used to estimate total, light, moderate, vigorous and moderate-to-vigorous PA. The associations between PA and incident type 2 diabetes were analysed using Cox-proportional hazard models. The mediating role of body mass index (BMI) was tested under a causal counterfactual framework. RESULTS: The median follow-up period was 6.3 years (IQR: 5.7-6.8), with 591 participants developing type 2 diabetes. Compared to those achieving < 150 min/week of moderate PA, people achieving 150-300, 300-600 and > 600 min/week were at 49% (95% CI 62-32%), 62% (95% CI 71-50%) and 71% (95% CI 80-59%) lower risk of type 2 diabetes, respectively. For vigorous PA, compared to those achieving < 25 min/week, individuals achieving 25-50, 50-75 and > 75 min/week were at 38% (95% CI 48-33%), 48% (95% CI 64-23%) and 64% (95% CI 78-42%) lower type 2 diabetes risk, respectively. Twelve per cent and 20% of the associations between vigorous and moderate PA and type 2 diabetes were mediated by lower BMI, respectively. CONCLUSIONS: PA has clear dose-response relationship with a lower risk of type 2 diabetes. Our findings support the current aerobic PA recommendations but suggest that additional PA beyond the recommendations is associated with even greater risk reduction. TRIAL REGISTRATION: The UK Biobank study was approved by the North West Multi-Centre Research Ethics Committee (Ref 11/NW/0382 on June 17, 2011).

Associations of grip strength and walking pace with mortality in stroke survivors: A prospective study from UK Biobank.

INTRODUCTION: Although stroke is an emerging cause of disability and mortality globally, associations between physical capability markers and mortality in stroke survivors are elusive. This study investigated the individual and combined associations of walking pace and grip strength with all-cause and stroke mortality in stroke survivors. METHODS: Individual and combined associations of walking pace and grip strength with stroke deaths and all-cause mortality were investigated using Cox proportional-hazard models adjusted for sociodemographic, lifestyle, and health-related variables. RESULTS: Seven thousand four hundred eighty-six stroke survivors from the UK Biobank study (aged 40-70 years; 42.4% women) were included in this prospective study. Over a median follow-up of 12.6 (IQR: 11.9-13.3) years, 1490 (19.9%) participants died, of whom 222 (3.0%) died from stroke. After adjusting for confounding factors, and compared to individuals in the average/brisk walking pace category, those who reported a slow walking pace had 2.00 (95% CI: 1.50-2.68) and 1.99 (95% CI: 1.78-2.23) times higher risk of stroke mortality and all-cause mortality, respectively. Similar associations were identified for participants with low grip strength compared with those with normal levels. For combined associations, those with both slow walking pace and low grip strength showed the highest risk of stroke mortality (hazard ratio: 2.86 [95% CI: 1.93-4.22]). Similar results were found for all-cause mortality. CONCLUSIONS: Low grip strength and slow walking pace were associated with a higher risk of stroke and all-cause mortality in stroke survivors. If these associations are causal, improving physical capability among stroke survivors might potentially prolong survival.

Association between walking pace and incident type 2 diabetes by adiposity level: A prospective cohort study from the UK Biobank.

AIMS: To investigate the combined association of adiposity and walking pace with incident type 2 diabetes. METHODS: We undertook a prospective cohort study in 194 304 White-European participants (mean age 56.5 years, 55.9% women). Participants' walking pace was self-reported as brisk, average or slow. Adiposity measures included body mass index (BMI), waist circumference (WC) and body fat percentage (BF%). Associations were investigated using Cox proportional hazard models, with a 2-year landmark analysis. A four-way decomposition analysis was used for mediation and additive interaction. RESULTS: The median (interquartile range) follow-up was 5.4 (4.8-6.3) years. During the follow-up period, 4564 participants developed type 2 diabetes. Compared to brisk-walking participants with normal BMI, those with obesity who walked briskly were at an approximately 10- to 12-fold higher risk of type 2 diabetes (hazard ratio [HR] 9.64, 95% confidence interval [CI] 7.24-12.84, in women; HR 11.91, 95% CI 8.80-16.12, in men), whereas those with obesity and walked slowly had an approximately 12- to 15-fold higher risk (HR 12.68, 95% CI 9.62-16.71, in women; HR 15.41, 95% CI 11.27-21.06, in men). There was evidence of an additive interaction between WC and BF% and walking pace among women, explaining 17.8% and 47.9% excess risk respectively. Obesity mediated the association in women and men, accounting for 60.1% and 44.9%, respectively. CONCLUSIONS: Slow walking pace is a risk factor for type 2 diabetes independent of adiposity. Promoting brisk walking as well as weight management might be an effective type 2 diabetes prevention strategy given their synergistic effects.

Dietary weight-management for type 2 diabetes remissions in South Asians: the South Asian diabetes remission randomised trial for proof-of-concept and feasibility (STANDby).

Background: We aimed to assess whether a structured weight management programme incorporating a total diet replacement (TDR) (3-5 months ∼850 kcal/day formula diet) weight loss phase is acceptable to people of South Asian ethnicity and can achieve type 2 diabetes (T2D) remissions similarly to other populations. Methods: Adults of South Asian ethnicity, aged 18-65 years, with T2D for ≤4 years, and BMI 25-45 kg/m2 were recruited from primary care and social media, and randomised to commence TDR either immediately (iTDR), or delayed (dTDR) for 3-5 months as a usual care control arm during this period. Intervention effects were tested in randomised comparisons powered to detect significant weight loss, and in an expanded observational analysis to determine remission effect size, including both iTDR and dTDR groups. Acceptability in those recruited was explored by questionnaire and weight change. Trial registration: Current Controlled Trials, ISRCTN10720065. Date of Registration 27/09/2017. Findings: Twenty-five eligible individuals were recruited. Mean baseline (SD) age was 45.8 (11.1) years, weight 88.2 (13.7) kg, BMI 32.1 (3.8) kg/m2, HbA1c 60.4 (11.3) mmol/mol, liver fat by MRI 15.6 (9.4)%. In the RCT, mean(SD) weight change after TDR was -7.7 (7.2)% in the intervention group (n = 13), and -1.2 (1.4)% in the usual-care control group (n = 12) (p = 0.005), with T2D remission achieved by 5/13, compared to 0/12 respectively (p = 0.039). In the observational study, 23/25 started TDR and 19/23 participants completed the TDR phase. Median time spent in TDR was 105 days (IQR 77-134 days). T2D remission was achieved in 10/23 (43%), and weight changes were concordant with the RCT. Overall, 8/23 (35%) lost over 10% bodyweight. Absolute liver fat proportion near halved from 15.3% at the start of TDR to 8.6% (p < 0.001). Interpretation: In UK-based South Asians, TDR-led weight loss and T2D remission rates are comparable to those observed in white cohorts, and the intervention was acceptable in most of those recruited. There is potential to further improve outcomes, but one-third lost >10% body weight, and the mechanism underpinning T2D remission appears similar, driven by weight change with loss of excess ectopic body-fat. Funding: We gratefully acknowledge funding for the MRI scans from the, Miss MJM Smith Trust (registered charity: SC040586). No other external funds were provided for this trial. NS is supported by the British Heart Foundation Research Excellence Award (RE/18/6/34217).

Qualitative study of practices and attitudes towards physical activity among prediabetic men and women in urban and rural Malawi.

OBJECTIVES: Given the decline in physical activity levels in Malawi, like other sub-Saharan African countries, and its implication for non-communicable disease (NCD) prevention, this study aimed to compare and contrast accounts of practices and attitudes towards physical activity among Malawian men and women (previously identified as having pre-diabetes) in urban and rural settings. SETTING: Two communities: one urban (Lilongwe) and one rural (Karonga). PARTICIPANTS: 14 men (urban N=6, rural N=8) and 18 women (urban N=9, rural N=9) classified as prediabetic during their participation in an NCD survey 3-5 years previously. DESIGN: A qualitative focus group study (N=4) and thematic analysis, with the ecological model used as a framework to characterise the types of physical activity people engaged in and potential ways to support them to exercise more. RESULTS: Participants reported undertaking different types of physical activity across all ecological model domains (household, occupational, transport, recreational). Rural participants reported more vigorous physical activities than urban participants, and women reported more household activities than men. Many participants recognised a need to promote physical activity in Malawi, and the health benefits of doing so, including the importance of physical activity in helping them stay strong to maintain physical functioning. Barriers to physical activity included competing priorities (especially urban men), societal expectations around wealth, use of motorised transport, lack of accessible facilities for women, ageing and ill health. CONCLUSIONS: Physical activity is declining in Malawi as working and transport practices change in response to economic development, making promotion of alternative forms of physical activity a public health priority. Multilevel interventions emphasising the personal benefits/value of physical activity for all ages, and routine and group-based exercising, as well as investment in accessible recreational facilities (including for women) and active travel infrastructure should be considered to improve physical activity levels in Malawi.

Liver, visceral and subcutaneous fat in men and women of South Asian and white European descent: a systematic review and meta-analysis of new and published data.

AIMS/HYPOTHESIS: South Asians have a two- to fivefold higher risk of developing type 2 diabetes than those of white European descent. Greater central adiposity and storage of fat in deeper or ectopic depots are potential contributing mechanisms. We collated existing and new data on the amount of subcutaneous (SAT), visceral (VAT) and liver fat in adults of South Asian and white European descent to provide a robust assessment of potential ethnic differences in these factors. METHODS: We performed a systematic review of the Embase and PubMed databases from inception to August 2021. Unpublished imaging data were also included. The weighted standardised mean difference (SMD) for each adiposity measure was estimated using random-effects models. The quality of the studies was assessed using the ROBINS-E tool for risk of bias and overall certainty of the evidence was assessed using the GRADE approach. The study was pre-registered with the OSF Registries ( https://osf.io/w5bf9 ). RESULTS: We summarised imaging data on SAT, VAT and liver fat from eight published and three previously unpublished datasets, including a total of 1156 South Asian and 2891 white European men, and 697 South Asian and 2271 white European women. Despite South Asian men having a mean BMI approximately 0.5-0.7 kg/m2 lower than white European men (depending on the comparison), nine studies showed 0.34 SMD (95% CI 0.12, 0.55; I2=83%) more SAT and seven studies showed 0.56 SMD (95% CI 0.14, 0.98; I2=93%) more liver fat, but nine studies had similar VAT (-0.03 SMD; 95% CI -0.24, 0.19; I2=85%) compared with their white European counterparts. South Asian women had an approximately 0.9 kg/m2 lower BMI but 0.31 SMD (95% CI 0.14, 0.48; I2=53%) more liver fat than their white European counterparts in five studies. Subcutaneous fat levels (0.03 SMD; 95% CI -0.17, 0.23; I2=72%) and VAT levels (0.04 SMD; 95% CI -0.16, 0.24; I2=71%) did not differ significantly between ethnic groups in eight studies of women. CONCLUSIONS/INTERPRETATION: South Asian men and women appear to store more ectopic fat in the liver compared with their white European counterparts with similar BMI levels. Given the emerging understanding of the importance of liver fat in diabetes pathogenesis, these findings help explain the greater diabetes risks in South Asians. FUNDING: There was no primary direct funding for undertaking the systematic review and meta-analysis.

The influence of socioeconomic status on the association between unhealthy lifestyle factors and adverse health outcomes: a systematic review.

Background: Combinations of lifestyle factors (LFs) and socioeconomic status (SES) are independently associated with cardiovascular disease (CVD), cancer, and mortality. Less advantaged SES groups may be disproportionately vulnerable to unhealthy LFs but interactions between LFs and SES remain poorly understood. This review aimed to synthesise the available evidence for whether and how SES modifies associations between combinations of LFs and adverse health outcomes. Methods: Systematic review of studies that examine associations between combinations of >3 LFs (eg.smoking/physical activity/diet) and health outcomes and report data on SES (eg.income/education/poverty-index) influences on associations. Databases (PubMed/EMBASE/CINAHL), references, forward citations, and grey-literature were searched from inception to December 2021. Eligibility criteria were analyses of prospective adult cohorts that examined all-cause mortality or CVD/cancer mortality/incidence. Results: Six studies (n=42,467-399,537; 46.5-56.8 years old; 54.6-59.3% women) of five cohorts were included. All examined all-cause mortality; three assessed CVD/cancer outcomes. Four studies observed multiplicative interactions between LFs and SES, but in opposing directions. Two studies tested for additive interactions; interactions were observed in one cohort (UK Biobank) and not in another (National Health and Nutrition Examination Survey (NHANES)). All-cause mortality HRs (95% confidence intervals) for unhealthy LFs (versus healthy LFs) from the most advantaged SES groups ranged from 0.68 (0.32-1.45) to 4.17 (2.27-7.69). Equivalent estimates from the least advantaged ranged from 1.30 (1.13-1.50) to 4.00 (2.22-7.14). In 19 analyses (including sensitivity analyses) of joint associations between LFs, SES, and all-cause mortality, highest all-cause mortality was observed in the unhealthiest LF-least advantaged suggesting an additive effect. Conclusions: Limited and heterogenous literature suggests that the influence of SES on associations between combinations of unhealthy LFs and adverse health could be additive but remains unclear. Additional prospective analyses would help clarify whether SES modifies associations between combinations of unhealthy LFs and health outcomes. Registration: Protocol is registered with PROSPERO (CRD42020172588;25 June 2020).

Association of wearable device-measured vigorous intermittent lifestyle physical activity with mortality.

Wearable devices can capture unexplored movement patterns such as brief bursts of vigorous intermittent lifestyle physical activity (VILPA) that is embedded into everyday life, rather than being done as leisure time exercise. Here, we examined the association of VILPA with all-cause, cardiovascular disease (CVD) and cancer mortality in 25,241 nonexercisers (mean age 61.8 years, 14,178 women/11,063 men) in the UK Biobank. Over an average follow-up of 6.9 years, during which 852 deaths occurred, VILPA was inversely associated with all three of these outcomes in a near-linear fashion. Compared with participants who engaged in no VILPA, participants who engaged in VILPA at the sample median VILPA frequency of 3 length-standardized bouts per day (lasting 1 or 2 min each) showed a 38%-40% reduction in all-cause and cancer mortality risk and a 48%-49% reduction in CVD mortality risk. Moreover, the sample median VILPA duration of 4.4 min per day was associated with a 26%-30% reduction in all-cause and cancer mortality risk and a 32%-34% reduction in CVD mortality risk. We obtained similar results when repeating the above analyses for vigorous physical activity (VPA) in 62,344 UK Biobank participants who exercised (1,552 deaths, 35,290 women/27,054 men). These results indicate that small amounts of vigorous nonexercise physical activity are associated with substantially lower mortality. VILPA in nonexercisers appears to elicit similar effects to VPA in exercisers, suggesting that VILPA may be a suitable physical activity target, especially in people not able or willing to exercise.

Development and optimisation of a multi-component workplace intervention to increase cycling for the Cycle Nation Project.

The Cycle Nation Project (CNP) aimed to develop, test the feasibility of and optimize a multi-component individual-/social-level workplace-based intervention to increase cycling among office staff at a multinational bank (HSBC UK). To do this, we first explored barriers to cycling in a nationally-representative survey of UK adults, then undertook focus groups with bank employees to understand any context-specific barriers and ways in which these might be overcome. These activities led to identification of 10 individual-level, two social-level, and five organizational-level modifiable factors, which were mapped to candidate intervention components previously identified in a scoping review of cycling initiatives. Interviews with HSBC UK managers then explored the practicality of implementing the candidate intervention components in bank offices. The resultant pilot CNP intervention included 32 core components across six intervention functions (education, persuasion, incentivisation, training, environmental restructuring, enablement). Participants received a loan bike for 12-weeks (or their own bike serviced), and a 9-week cycle training course (condensed to 6 weeks for those already confident in basic cycling skills), including interactive information sharing activities, behavior change techniques (e.g., weekly goal setting), bike maintenance training, practical off-road cycling skill games and on-road group rides. Sessions were delivered by trained bank staff members who were experienced cyclists. The CNP pilot intervention was delivered across three sites with 68 participants. It was completed in two sites (the third site was stopped due to COVID-19) and was feasible and acceptable to both women and men and across different ethnicities. In addition, the CNP intervention was successful (at least in the short term) in increasing cycling by 3 rides/week on average, and improving perceptions of safety, vitality, confidence, and motivation to cycle. Following minor modifications, the long-term effectiveness and cost-effectiveness of the CNP intervention should be tested in a full-scale randomized controlled trial.

Device-measured physical activity and incident affective disorders.

BACKGROUND: Studies on physical activity (PA) and mental health are largely limited to self-reported PA. This study aims to use prospective cohort data to investigate the association between device-measured PA and affective disorders. METHODS: A total of 37,327 participants from UK Biobank who had not had any prior affective disorder diagnoses were included in this prospective cohort study. Wrist-worn accelerometers were used to measure total, light (LPA), moderate (MPA), and vigorous (VPA) PA. Associations between PA domains and affective disorders were analysed using penalised splines in Cox proportional hazard models. Analyses were adjusted for other intensity-specific PA and sociodemographic and lifestyle factors. Sensitivity analyses were conducted adjusting for body mass index and longstanding illnesses as well as excluding events in the first 2 years of follow-up. Preventable fractions for the population were estimated for MPA and VPA. RESULTS: Over a median follow-up of 6.8 years, 1262 (3.4%) individuals were diagnosed with affective disorders. Replacing 30 min of sedentary behaviour in a week with MPA (HR 0.95, 95% CI 0.94-0.97) or VPA (HR 0.91, 95% CI 0.85-0.98) was associated with lower risk of affective behaviours, up to 500 and 120 min of MPA and VPA. Assuming causality, 5.14% and 18.88% of affective disorders could have been prevented if MPA ≥150 min/week and VPA ≥75 min/week were achieved, respectively, across the study population. CONCLUSIONS: Device-measured MPA and VPA were associated with lower risk of affective disorders. The potential mental health benefits of MPA continue to accrue above the current World Health Organization recommendation.