Validity of the International Physical Activity Questionnaire and the Singapore Prospective Study Program physical activity questionnaire in a multiethnic urban Asian population

Rationale, Design, and Baseline Characteristics of Participants in the Health@NUS mHealth Augmented Cohort Study Examining Student-to-Work Life Transition: Protocol for a Prospective Cohort Study

BACKGROUND

Integration of mobile health data collection methods into cohort studies enables the collection of intensive longitudinal information, which gives deeper insights into individuals' health and lifestyle behavioral patterns over time, as compared to traditional cohort methods with less frequent data collection. These findings can then fill the gaps that remain in understanding how various lifestyle behaviors interact as students graduate from university and seek employment (student-to-work life transition), where the inability to adapt quickly to a changing environment greatly affects the mental well-being of young adults.

OBJECTIVE

This paper aims to provide an overview of the study methodology and baseline characteristics of participants in Health@NUS, a longitudinal study leveraging mobile health to examine the trajectories of health behaviors, physical health, and well-being, and their diverse determinants, for young adults during the student-to-work life transition.

METHODS

University students were recruited between August 2020 and June 2022 in Singapore. Participants would complete biometric assessments and questionnaires at 3 time points (baseline, 12-, and 24-month follow-up visits) and use a Fitbit smartwatch and smartphone app to continuously collect physical activity, sedentary behavior, sleep, and dietary data over the 2 years. Additionally, up to 12 two-week-long bursts of app-based ecological momentary surveys capturing lifestyle behaviors and well-being would be sent out among the 3 time points.

RESULTS

Interested participants (n=1556) were screened for eligibility, and 776 participants were enrolled in the study between August 2020 and June 2022. Participants were mostly female (441/776, 56.8%), of Chinese ethnicity (741/776, 92%), undergraduate students (759/776, 97.8%), and had a mean BMI of 21.9 (SD 3.3) kg/m2, and a mean age of 22.7 (SD 1.7) years. A substantial proportion were overweight (202/776, 26.1%) or obese (42/776, 5.4%), had indicated poor mental well-being (World Health Organization-5 Well-Being Index ≤50; 291/776, 37.7%), or were at higher risk for psychological distress (Kessler Psychological Distress Scale ≥13; 109/776, 14.1%).

CONCLUSIONS

The findings from this study will provide detailed insights into the determinants and trajectories of health behaviors, health, and well-being during the student-to-work life transition experienced by young adults.

TRIAL REGISTRATION

ClinicalTrials.gov NCT05154227; https://clinicaltrials.gov/study/NCT05154227.

INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID)

DERR1-10.2196/56749.

Validity and reliability of the international physical activity questionnaire short form in Chilean adults

PURPOSE

This study aimed to determine the test-retest reliability and concurrent validity of the International Physical Activity Questionnaire Short Form (IPAQ-SF) in Chilean adults.

METHODS

A cross-sectional validation study was carried out on 161 adults aged between 35 and 65, selected from a population-based study in Temuco, Chile. IPAQ-SF was completed twice, seven days apart, to analyze the test-retest reliability with the intraclass correlation coefficient (ICC). Objective PA was assessed by accelerometry (ActiGraph GT3X+) for seven consecutive days. Intraclass correlation coefficients were used to determine the reliability. Spearman correlation coefficients (rho) and Bland-Altman plots were calculated to assess validity.

RESULTS

144 subjects (52.5 ± 8.8 years, 53.9% men) answered the IPAQ-SF on both occasions and had valid accelerometry data. The IPAQ-SF showed moderate reliability for sitting time (ICC = 0.62), while it was poor for walking (ICC = 0.40), moderate PA (ICC = 0.41), vigorous PA (ICC = 0.48), and total PA (ICC = 0.33). There were weak correlations between IPAQ-SF and accelerometry for sedentary behavior (rho = 0.28, p = 0.0005), walking (rho = 0.11, p = 0.17), moderate PA (rho = 0.13, p = 0.128), vigorous PA (rho = 0.18, p = 0.03), and total PA (rho = 0.26, p = 0.002).

CONCLUSIONS

The results suggest that the IPAQ-SF test and retest would provide an acceptable measure of total SB and MVPA, and a weak correlation between IPAQ-SF and accelerometer.

Physical activity and sedentary time distribution among adult residents during COVID-19 circuit breaker movement restrictions in Singapore: a public health perspective

Introduction

Social lockdowns and quarantines have been enforced in various populations to mitigate the spread of coronavirus disease 2019 (COVID-19) in the community. This study investigated the impact of COVID-19 lockdown, known as circuit breaker movement restrictions (CBMR), on physical activity (PA) and sedentary time (ST) distribution patterns among Singapore residents aged 21-65 years.

Methods

This was a cross-sectional retrospective study that utilised a 44-item questionnaire that included sections to determine PA and ST distribution patterns before and during CBMR. It also included information on sleep duration, PA preference and routine, awareness of local initiatives and perceptions on barriers towards PA during the CBMR period.

Results

There was an overall decrease in PA and a significant increase in physical inactivity and ST during the CBMR period. A greater proportion of participants reported sleeping for longer hours, suggesting positive adaptations in sleep habits during CBMR. Majority were unaware of online exercise initiatives and programmes offered during the CBMR period, and >50% of the respondents never used an online resource for exercise. Singapore residents seemed to prefer outdoor and facility-based venues for exercise and PA, and closure of facilities was the primary barrier for PA during the CBMR period.

Conclusion

Reduced PA and increased ST during CBMR reflect negative lifestyle adaptations and may have adverse public health implications. Increased sleep duration suggests successful coping, which may consequently lead to physical and mental health benefits. While Singapore adult residents may be flexible with certain aspects of being physically active, they seemed less adaptive to changes in type of exercise, facility and environment.

Acculturation as a Determinant of Obesity and Related Lifestyle Behaviors in a Multi-Ethnic Asian Population

Limited attention has been given to the role of cultural orientation towards different ethnic groups in multi-ethnic settings without a dominant host culture. We evaluated whether acculturation levels, reflecting cultural orientation towards other ethnic groups, were associated with obesity and related lifestyle behaviors in a cosmopolitan Asian population. We conducted the current study based on data from the Singapore Multi-Ethnic Cohort (N = 10,622) consisting of ethnic Chinese, Malays, and Indians aged 21 to 75 years. Multivariable linear and logistic regression analyses were used to examine associations between the acculturation level (z-score), obesity, and related lifestyle behaviors, including dietary habits and physical activity. A higher acculturation level was directly associated with a higher prevalence of obesity among Chinese, whereas an inverse association was found for ethnic Indians, and no significant association in Malays. In ethnic Malays, greater acculturation was significantly associated with higher dietary quality and less sedentary time. Furthermore, a high acculturation level was significantly associated with higher sugar-sweetened beverage consumption and more leisure-time PA in all ethnic groups. Our findings suggest that greater cultural orientation towards other ethnic groups was associated with convergence in obesity levels. More research is required to understand how acculturation affects obesity-related lifestyle factors in multi-ethnic settings.

Differences in type 2 diabetes risk between East, South, and Southeast Asians living in Singapore: the multi-ethnic cohort

INTRODUCTION

Prospective data on differences in type two diabetes (T2D) risk between Asian ethnic groups are sparse. We, therefore, compared T2D risk for East (Chinese), South (Indian), and Southeast (Malay) Asians and examined biological factors that may contribute to ethnic differences.

RESEARCH DESIGN AND METHODS

We included 7427 adults of Chinese, Malay, and Indian origin participating in the Singapore multi-ethnic cohort. Information on sociodemographic, lifestyle, and biological risk factors (body mass index (BMI), waist circumference, blood lipids, blood pressure, C reactive protein, adiponectin, and homeostasis model assessment for insulin resistance and beta-cell function) were collected using standardized interviews and physical examinations. T2D cases were based on physician diagnoses, a national medical registry, fasting plasma glucose, or glycated hemoglobin A1c. We used multivariable logistic association and mediation analyses.

RESULTS

During an average follow-up of 7.2 years (SD 2.2 years), we documented 595 cases of incident diabetes. Ethnic Malays (OR 2.08, 95% CI 1.69 to 2.56) and Indians (OR 2.22, 95% CI 1.80 to 2.74) had an approximately twofold higher risk of T2D compared with ethnic Chinese. Higher BMI explained the higher risk for Malay compared with Chinese ethnicity. Higher BMI, waist circumference, inflammation, and insulin resistance, and lower beta-cell function and high-density lipoprotein-cholesterol significantly contributed to the higher T2D risk for Indian compared with Chinese ethnicity. However, part of the higher T2D risk associated with Indian ethnicity remained unexplained. Despite their lower diabetes risk, Chinese participants had the lowest adiponectin levels.

CONCLUSIONS

Different Asian ethnic groups have unique biological risk factor profiles related to T2D development that may warrant targeted approaches for prevention and treatment.

Association Between Domain-Specific Physical Activity and Cardiometabolic Factors in a Multiethnic Asian Population: A Longitudinal Study

AIMS

To examine the association between domain-specific physical activity (PA) and cardiometabolic factors with longitudinal data, which is limited in current literature.

METHODS

Participants who attended the Singapore Multi-Ethnic Cohort and follow-up surveys were included in this study (N = 3950, mean age: 44.7 y, female: 57.9%). Self-reported moderate- to vigorous-intensity PA (MVPA) for each domain (leisure-time, transportation, occupation, and household) was categorized into 4 levels: no, low, middle, and high MVPA. The longitudinal associations of domain-specific MVPA with cardiometabolic factors including systolic and diastolic blood pressures, low-density and high-density lipoprotein cholesterols, triglycerides, and body mass index were examined using Generalized Estimating Equations, accounting for confounding factors and repeated measurements.

RESULTS

There were 5.2% participants who had no MVPA. For each domain, this rate ranged from 22.6% (household) to 83.3% (occupation). Leisure-time and occupation MVPAs had positive and linear associations with high-density lipoprotein cholesterols, corresponding to 0.030 (95% confidence interval, 0.015 to 0.045) mmol/L (leisure-time) and 0.063 (95% confidence interval, 0.043 to 0.083) mmol/L (occupation), when compared high with no respective MVPA. Occupation and household MVPAs were associated with low-density lipoprotein cholesterol. Transportation and occupation exhibited a positive and linear relationship with diastolic blood pressure. None of the domains were associated with body mass index, systolic blood pressures, or triglycerides.

CONCLUSIONS

This study showed that each domain had differential association with individual cardiometabolic risk factors. As occupation, transportation, or household PA had unfavorable associations with low-density lipoprotein cholesterol or diastolic blood pressure, the overall beneficial impact of higher PA levels may not necessarily hold in the context of domain-specific PA and cardiovascular health. Further investigation is needed to corroborate our findings.

Association between Shift Work Schedules and Cardiovascular Events in a Multi-Ethnic Cohort

BACKGROUND

Shift work is known to increase the risk of cardiometabolic diseases and mortality. We investigate the relationship between shift work schedules and cardiometabolic risk factors (smoking, hypertension, and obesity) and their association with cardiometabolic diseases (diabetes and cardiovascular diseases) in a multi-ethnic population from Singapore.

METHODS

2469 participants from the Singapore-based Multi-Ethnic Cohort underwent physical and clinical assessments. Shift work schedules (morning, evening, night, and mixed) were assessed using a validated questionnaire.

RESULTS

Among shift workers, night shift workers had a significantly higher prevalence of smoking (54.5%), diabetes (27.3%), and cardiovascular events (14.1%). Compared to non-shift workers, workers in the night (OR = 2.10, 95%CI: 1.26-3.41) and mixed (OR = 1.74, 95%CI: 1.22-2.48) shift groups were more likely to be current smokers. A significant association between shift duration and smoking (OR = 1.02, 95%CI: 1.00-1.03) was also observed, with longer shift duration (in years) leading to an increase in smoking behavior. No significant associations were found between shift work schedules and hypertension, obesity (BMI), diabetes, and cardiovascular disease, as well as other cardiometabolic risk factors and diseases.

CONCLUSION

This study found that shift schedules and shift duration were most strongly associated with smoking status after covariate adjustments (age, gender, ethnicity, socioeconomic status, and work arrangement), with night and mixed shift types being strongly associated with current smoker status. As smoking is a modifiable risk factor for cardiometabolic disease, employers of shift workers should increase work-based health interventions to control smoking and promote a healthier workforce.

Handgrip Strength and Cognitive Performance in a Multiethnic Cohort in Singapore

BACKGROUND

Handgrip strength (HGS) is an important marker of frailty but there is limited research on lifestyle and vascular determinants of HGS and its relationship with cognitive impairment.

OBJECTIVE

To identify determinants of HGS and the association of HGS with cognitive impairment in a multiethnic cohort from Singapore.

METHODS

This study (n = 2,109, median [Q1, Q3] age: 53 [48, 60] years, 59.6% women) was based on cross-sectional data from Singapore Multi-Ethnic Cohort. HGS was collected using hand-held Electronic Dynamometer. The potential determinants of HGS included age, sex, ethnicity, smoking, physical activity, serum cholesterol and history of hypertension, diabetes, and stroke. Cognition, assessed with the Mini-Mental State Examination (MMSE), was analyzed as both continuous and binary outcome (cognitively impaired [scores < 26] and cognitively normal [scores≥26]).

RESULTS

In total, 239 (11.3%) participants were cognitively impaired. Older age, female sex, Malay or Indian compared with Chinese ethnicity, and diabetes history were associated with decreased HGS, whereas higher education, higher body mass index, and more physical activity were associated with higher HGS. Higher HGS was associated with higher MMSE scores (β: 0.34, 95% CI: 0.20, 0.49) and 37% lower odds of cognitive impairment (OR: 0.63, 95% CI: 0.49-0.82). These associations were significantly stronger in participants who were older (50-90 years), female, of Malay and Indian ethnicity (compared with Chinese), and less educated.

CONCLUSION

In this multi-ethnic Asian population, demographics, vascular risk factors, and lifestyle behaviors were associated with HGS. Additionally, higher HGS was associated with substantially better cognitive function, which association was modified by age, sex, ethnicity, and education level.

Criterion validity of the Saltin-Grimby Physical Activity Level Scale in adolescents. The Fit Futures Study

Background

The Saltin-Grimby Physical Activity Level Scale (SGPALS) is commonly used to measure physical activity (PA) in population studies, but its validity in adolescents is unknown. This study aimed to assess the criterion validity of the SGPALS against accelerometry in a large sample of adolescents. A secondary aim was to examine the validity across strata of sex, body mass index (BMI), parental educational level, study program and self-reported health.

Methods

The study is based on data from 572 adolescents aged 15–17 years who participated in the Fit Futures Study 2010–11 in Northern Norway. The participants were invited to wear an accelerometer (GT3X) attached to their hip for seven consecutive days. We used Spearman’s rho and linear regression models to assess the validity of the SGPALS against the following accelerometry estimates of PA; mean counts/minute (CPM), steps/day, and minutes/day of moderate-to-vigorous physical activity (MVPA).

Results

The SGPALS correlated with mean CPM (ρ = 0.40, p<0.01), steps/day (ρ = 0.35, p<0.01) and MVPA min/day (ρ = 0.35, p<0.01). We observed no differences between correlations within demographic strata (all p>0.001). Higher scores on SGPALS were associated with a higher CPM, higher number of steps per day and more minutes of MVPA per day, with the following mean differences in PA measurements between the SGPALS ranks: CPM increased by 53 counts (95% CI: 44 to 62), steps/day increased by 925 steps (95% CI: 731 to 1118), and MVPA by 8.4 min/day (95% CI: 6.7 to 10.0). Mean difference between the highest and lowest SGPALS category was 2947 steps/day (6509 vs. 9456 steps/day) and 26.4 min/day MVPA (35.2 minutes vs 61.6 minutes).

Conclusion

We found satisfactory ranking validity of SGPALS measured against accelerometry in adolescents, which was fairly stable across strata of sex, BMI, and education. However, the validity of SGPALS in providing information on absolute physical activity levels seem limited.

Dietary patterns and predicted 10-year cardiovascular disease risk in a multiethnic Asian population

BACKGROUND AND AIMS

Studies examining associations between dietary patterns and Framingham risk score (FRS) and predicted 10-year cardiovascular diseases (CVD) risk in an Asian population are lacking. This study aimed to identify a posteriori dietary patterns across three major ethnic groups in Singapore and ascertain their associations with locally modified FRS and predicted 10-year CVD risk.

METHODS AND RESULTS

This cross-sectional study included 8594 Singapore residents (aged 21-75 years) from the Singapore Multi-Ethnic Cohort. Data on sociodemographic and lifestyle factors were collected via questionnaires. Food consumption was assessed using a validated Food Frequency Questionnaire. Dietary patterns were identified using principal component analysis and associations with CVD risk factors, FRS and predicted CVD risk (%) were analysed using multiple linear and logistic regression. Four dietary patterns emerged that explained 25.6% of variance. The 'processed food and sugar-sweetened beverages' pattern was significantly associated with higher FRS (β: 0.13; 95% CI: 0.04, 0.23), while the 'ethnic breads, legumes and nuts' (β: 0.13; 95% CI: 0.22, -0.04) and 'whole grains, fruit and dairy' (β: 0.17; 95% CI: 0.24, -0.10) patterns were significantly associated with lower FRS. The 'meat and vegetables' pattern was not significantly associated with FRS. Increased adherence to the 'whole grains, fruit and dairy' pattern was associated with lower odds of having predicted CVD risk of ≥10% (p-trend: 0.03).

CONCLUSION

Adherence to the 'ethnic breads, legumes and nuts' and 'whole grains, fruit and dairy' patterns was associated with a lower predicted CVD risk, and an inverse association for the 'processed food and sugar-sweetened beverages' pattern in an Asian population. These findings can inform the development of culturally sensitive dietary interventions to prevent CVD.

Replacing dietary carbohydrates and refined grains with different alternatives and risk of cardiovascular diseases in a multi-ethnic Asian population

BACKGROUND

Cardiovascular diseases (CVDs) are a major cause of deaths worldwide, but prospective data on dietary risk factors for CVD in South and Southeast Asian populations are sparse.

OBJECTIVE

We aimed to evaluate the relation between macronutrient and food intakes and incidence of major adverse cardiovascular events (MACEs) in a multi-ethnic Asian population.

METHODS

We used data from the Singapore Multi-Ethnic Cohort (n = 12,408), a prospective cohort of ethnic Chinese, Malay, and Indian adults aged 21‒65 y recruited between 2004 and 2010. Dietary intakes were assessed using a validated food-frequency questionnaire, and the incidence of MACEs was ascertained through data linkage with national registries. A Cox proportional hazards model was used to evaluate the associations between dietary intakes and MACE risk.

RESULTS

Over a mean (SD) follow-up of 10.1 (2.3) y, 746 incident cases of MACEs were documented. We observed a direct association between carbohydrate intake and MACE risk (highest vs. lowest quartile, HR: 1.35; 95% CI: 1.07, 1.71; P-trend = 0.001). Replacing 5% of energy from carbohydrate with polyunsaturated fat (HR: 0.79; 95% CI: 0.69, 0.91) but not saturated fat (HR: 0.95; 95% CI: 0.84, 1.09) was significantly associated with a lower MACE risk. In terms of food groups, replacing 1 serving/d of refined grains with fruit (HR: 0.93; 95% CI: 0.87, 0.99), vegetables (HR: 0.92; 95% CI: 0.85, 1.00), and dairy (HR: 0.90; 95% CI: 0.82, 0.98) was associated with lower MACE risk. Cholesterol intake was associated with a higher MACE risk in ethnic Indians (highest vs. lowest quartile, HR: 2.40; 95% CI: 1.53, 3.75; P-trend < 0.001) but not in ethnic Malay or Chinese (P-interaction = 0.015).

CONCLUSIONS

Moderating carbohydrate intakes by increasing polyunsaturated fat intake and replacing refined grains with fruits, vegetables, and dairy was associated with lower MACE risk in Asian populations.

Advancing understanding of dietary and movement behaviours in an Asian population through real-time monitoring: Protocol of the Continuous Observations of Behavioural Risk Factors in Asia study (COBRA)

Background

Modifiable risk factors for non-communicable diseases, including eating an unhealthy diet and being physically inactive, are influenced by complex and dynamic interactions between people and their social and physical environment. Therefore, understanding patterns and determinants of these risk factors as they occur in real life is essential to enable the design of precision public health interventions.

Objective

This paper describes the protocol for the Continuous Observations of Behavioural Risk Factors in Asia study (COBRA). The study uses real-time data capture methods to gain a comprehensive understanding of eating and movement behaviours, including how these differ by socio-demographic characteristics and are shaped by people's interaction with their social and physical environment.

Methods

COBRA is an observational study in free-living conditions. We will recruit 1500 adults aged 21-69 years from a large prospective cohort study. Real-time data capture methods will be used for nine consecutive days: an ecological momentary assessment app with a global positioning system enabled to collect location data, accelerometers to measure movement, and wearable sensors to monitor blood glucose levels. Participants receive six EMA surveys per day between 8 a.m. and 9.30 p.m. to capture information on behavioural risk factors including eating behaviours and diet composition movement behaviours (physical activity, sedentary behaviour, sleep), and related contextual factors. The second wave of ecological momentary assessment surveys with a global positioning system enabled will be sent 6 months later. Data will be analysed using generalised linear models to examine associations between behavioural risk factors and contextual determinants.

Discussion

Findings from this study will advance our understanding of dietary and movement behaviours as they occur in real-life and inform the development of personalised interventions to prevent chronic diseases.

Taste of Modern Diets: The Impact of Food Processing on Nutrient Sensing and Dietary Energy Intake

BACKGROUND

Both fresh and processed foods are available in the modern food environment where taste can signal presence of nutrients. However, whether these taste-nutrient relationships are maintained across different degrees of food processing is not well understood, and less is known about the relative contribution of different taste qualities to population energy intakes.

OBJECTIVES

To investigate the association between perceived intensity of 6 taste modalities and a food's nutrient content in the context of food processing and to further examine the relative contribution of different taste clusters to total energy intakes, stratified by weight status.

METHODS

Diet and lifestyle data from the Singapore Multi-Ethnic Cohort Phase 2 (N = 7011; aged 21-75 y) were collected through interviewer-administrated questionnaires. Taste and nutrient profiles for each of the 269 Singaporean foods were derived using a published taste database and food composition table. Each food was then categorized into the NOVA food-processing classification (unprocessed, processed, ultra-processed) to compare the strength of taste-nutrient relationships. Multivariable-adjusted models were used to examine associations between relative consumption of foods from different taste clusters and processing categories, energy intake, and BMI (in kg/m2) within a population cohort.

RESULTS

Sweet taste and mono- and disaccharide content of foods were significantly associated across all processing categories, although this association was weaker among ultra-processed foods (UPFs) (r = 0.42) than among unprocessed foods (r = 0.72). In contrast, associations between fat sensation and fat content (r = 0.74), as well as salt taste and sodium content (r = 0.84), were stronger for UPFs. Individuals who had higher energy intakes or were overweight (BMI >23) derived significantly greater percentage of energy from processed foods rather than UPFs, and this energy was higher from "savory-fatty" and lower from "neutral" tasting foods than those with lower energy intakes and normal weight (all P < 0.001). Eighty percent of individuals' dietary energy was from both "savory-fatty" and "neutral" foods, independent of differences in total energy intake and weight status.

CONCLUSIONS

Taste-nutrient relationships are maintained across different degrees of food processing. Greater consumption of foods that have a high "savory-fatty" taste was associated with increased energy intakes and overweight in the Asian population.

APOC3 genetic variation, serum triglycerides, and risk of coronary artery disease in Asian Indians, Europeans, and other ethnic groups

BACKGROUND

Hypertriglyceridemia has emerged as a critical coronary artery disease (CAD) risk factor. Rare loss-of-function (LoF) variants in apolipoprotein C-III have been reported to reduce triglycerides (TG) and are cardioprotective in American Indians and Europeans. However, there is a lack of data in other Europeans and non-Europeans. Also, whether genetically increased plasma TG due to ApoC-III is causally associated with increased CAD risk is still unclear and inconsistent. The objectives of this study were to verify the cardioprotective role of earlier reported six LoF variants of APOC3 in South Asians and other multi-ethnic cohorts and to evaluate the causal association of TG raising common variants for increasing CAD risk.

METHODS

We performed gene-centric and Mendelian randomization analyses and evaluated the role of genetic variation encompassing APOC3 for affecting circulating TG and the risk for developing CAD.

RESULTS

One rare LoF variant (rs138326449) with a 37% reduction in TG was associated with lowered risk for CAD in Europeans (p = 0.007), but we could not confirm this association in Asian Indians (p = 0.641). Our data could not validate the cardioprotective role of other five LoF variants analysed. A common variant rs5128 in the APOC3 was strongly associated with elevated TG levels showing a p-value 2.8 × 10- 424. Measures of plasma ApoC-III in a small subset of Sikhs revealed a 37% increase in ApoC-III concentrations among homozygous mutant carriers than the wild-type carriers of rs5128. A genetically instrumented per 1SD increment of plasma TG level of 15 mg/dL would cause a mild increase (3%) in the risk for CAD (p = 0.042).

CONCLUSIONS

Our results highlight the challenges of inclusion of rare variant information in clinical risk assessment and the generalizability of implementation of ApoC-III inhibition for treating atherosclerotic disease. More studies would be needed to confirm whether genetically raised TG and ApoC-III concentrations would increase CAD risk.

Diet Quality and Lower Refined Grain Consumption are Associated With Less Weight Gain in a Multi-Ethnic Asian Adult Population

BACKGROUND

The prevalence of obesity is increasing in many Asian countries. However, longitudinal data on the impacts of dietary factors on weight gain in Asian populations are sparse.

OBJECTIVES

We evaluated the relationship between changes in intakes of nutrients, foods, and beverages and diet quality and long-term changes in body weight.

METHODS

We used data (n = 3064) from the Singapore Multi-Ethnic Cohort, a prospective cohort including Chinese, Indian, and Malay residents aged 21-65 years. Dietary intakes were assessed using an FFQ, and body weight and waist circumference were measured during health examinations. Diet quality was evaluated using the Dietary Approaches to Stop Hypertension (DASH) and Alternative Healthy Eating Index (AHEI-2010) scores. Data were collected at baseline (2004-2010) and follow-up (2011-2016), with a mean follow-up of 6.0 years. Linear regression was used to assess the associations between dietary changes and weight change, adjusted for socio-demographic and lifestyle variables.

RESULTS

Improvements in dietary quality scores (DASH, -0.34 kg per 5 points; AHEI-2010, -0.35 kg per 10 points) and replacement of carbohydrates with protein (-0.44 kg per 5% of energy) were significantly associated with less weight gain. Increased intakes of white rice (+0.25 kg per serving/d), soft drinks (+0.69 kg), red meat (+0.58 kg), and poultry with skin (+0.74 kg) were directly associated with weight gain. The replacement of 1 serving per day of white rice with whole grains (-0.68 kg), vegetables (-0.33 kg), poultry without skin (-0.79 kg), and eggs (-0.87 kg) was associated with less weight gain. Similar associations were observed between changes in dietary factors and changes in waist circumference.

CONCLUSIONS

Among Asian adults, increasing dietary quality, reducing soft drink consumption, and replacing white rice with whole grains, vegetables, and selected high-protein foods was associated with less weight gain.

Dietary Fat and Protein Intake in Relation to Plasma Sphingolipids as Determined by a Large-Scale Lipidomic Analysis

Sphingolipid concentrations have been associated with risk of type 2 diabetes and cardiovascular diseases. Because sphingolipids can be synthesized de novo from saturated fatty acids (SFA), dietary fatty acids may affect plasma sphingolipid concentrations. We aimed to evaluate dietary fat and protein intakes in relation to circulating sphingolipid levels. We used cross-sectional data from 2860 ethnic Chinese Singaporeans collected from 2004–2007. Nutrient intakes were estimated on the basis of a validated 159-item food frequency questionnaire. We quantified 79 molecularly distinct sphingolipids in a large-scale lipidomic evaluation from plasma samples. Higher saturated fat intake was associated with higher concentrations of 16:1;O2 sphingolipids including ceramides, monohexosylcermides, dihexosylceramides, sphingomyelins, and sphingosine 1-phosphates. Higher polyunsaturated fat intake was associated with lower plasma long-chain ceramides and long-chain monohexosylcermide concentrations. Protein intake was inversely associated with concentrations of most subclasses of sphingolipids, with the exception of sphingolipids containing a 16:1;O2 sphingoid base. Lower intake of saturated fat and higher intake of polyunsaturated fat and protein may decrease plasma concentrations of several sphingolipid classes. These findings may represent a novel biological mechanism for the impact of nutrient intakes on cardio-metabolic health.

Consumption of Foods With Higher Energy Intake Rates is Associated With Greater Energy Intake, Adiposity, and Cardiovascular Risk Factors in Adults

BACKGROUND

Both high energy density and fast eating rates contribute to excess energy intakes. The energy intake rate (EIR; kcal/min) combines both the energy density (kcal/g) and eating rate (g/min) of a food to quantify the typical rate at which calories of different foods are ingested.

OBJECTIVES

We describe the EIRs of diets in a multi-ethnic Asian population, and examine relationships between the consumption of high-EIR foods and total energy intake, body composition, and cardio-metabolic risk factors.

METHODS

Diet and lifestyle data from the Singapore Multi-Ethnic Cohort 2 (n = 7011; 21-75 y), were collected through interviewer-administrated questionnaires. The EIR for each of the 269 foods was calculated as the product of its eating rate and energy density. Multivariable models were used to examine associations between the relative consumption of foods with higher and lower EIRs and energy intake, body composition, and cardio-metabolic risks, after adjusting for age, sex, ethnicity, education level, physical activity, smoking status, and alcohol drinking status.

RESULTS

Individuals with higher daily energy intakes and with obesity consumed a significantly larger percentage of their energy from high-EIR foods, with a smaller relative intake of lower-EIR foods. Individuals with raised serum cholesterol also consumed a significantly higher proportion of high-EIR foods, whereas those without hypertension consumed a larger percentage of energy intake from low-EIR foods. Individuals classified as having a "very high" dietary EIR had a significantly 1.3 kg higher body weight (95% CI, 0.2-1.5; P = 0.013), 0.4 kg/m2 higher BMI (95% CI, 0.03-0.8; P = 0.037), and 1.2 cm larger waist circumference (95% CI, 0.2-2.2; P = 0.010), and were more likely to have abdominal overweight (OR, 1.3; 95% CI, 1.1-1.5; P < 0.001) than those with a "low" dietary EIR.

CONCLUSIONS

Comparing foods by their EIRs summarizes the combined impact of energy density and eating rate, and may identify foods and dietary patterns that are associated with obesogenic eating styles and higher diet-related cardiovascular disease risk in an Asian population.

The Association of Different Types of Leisure Time Physical Activities with Cardiometabolic Outcomes in Singapore-Findings from the Multi-Ethnic Cohort Study

The study aimed to investigate the association between leisure time physical activity (LTPA) subtypes and cardiometabolic outcomes in the Singapore Multi-Ethnic Cohort (MEC). Self-reported data on socio-demographics, lifestyle factors, LTPA subtypes, and health screening data on body-mass index (BMI), waist circumference (WC), systolic and diastolic blood pressure (SBP and DBP), triglycerides (TG), and HDL-and LDL cholesterol were collected. Multivariable linear regression analyses were used adjusting for confounders. The mean age of 9768 participants was 45.2 ± 12.5 years (57.3% female, 47.3% Chinese, 26.0% Malay, and 26.8% Indians). Overall, 65.8% engaged in LTPA, and walking, strength/fitness and running were most common. Higher total LTPA was associated with lower WC, DBP, TG, a trend towards lower BMI, and higher SBP and HDL. Running was beneficially associated with all outcomes except for SBP and LDL. Balance exercises (BMI, SBP and DBP), cycling (BMI, WC and HDL), and strength/fitness (BMI, WC, TG and HDL) were also favorably associated with a number of outcomes, whereas ball games (DBP and TG), dancing (HDL) and other LTPA (DBP) were only favorably associated with selected outcomes. Unfavorable associations were found for total LTPA (SBP), strength/fitness (SBP), golf (DBP) and swimming (BMI and WC). Further research is warranted to inform future health promotion efforts.

Coffee, Black Tea, and Green Tea Consumption in Relation to Plasma Metabolites in an Asian Population

SCOPE

Coffee and tea are among the most popular beverages in the world. However, the association between habitual coffee, green tea, and black tea consumption with metabolomics profiles in Asian populations remain largely unknown.

METHODS AND RESULTS

158 metabolites (14 amino acids, 45 acylcarnitines, and 99 sphingolipids) in the blood plasma of participants are measured from the population-based Singapore Prospective Study Program cohort using mass spectrometry (MS). Linear regression models are used to obtain the estimates for the association between coffee and tea consumption with metabolite levels, adjusted for potential confounders and false discovery rate (FDR). Coffee consumption is significantly associated with higher levels of 63 sphingolipids (29 sphingomyelins, 32 ceramides, a sphingosine-1-phosphate, and a sphingosine) and lower levels of 13 acylcarnitines and alanine. Black tea consumption is significantly associated with higher levels of eight sphingolipids, and lower levels of an amino acid, whereas green tea is significantly inversely associated with four metabolites (C8:1-OH acylcarnitine, ganglioside GM3 d18:1/16:0, sphingomyelins d18:2/18:0 and d18:1/14:0).

CONCLUSIONS

Coffee, black tea, and green tea consumption are associated with plasma levels of certain classes of sphingolipids and acylcarnitines in an Asian population, particularly sphingomyelins, which may mediate the health benefits of these beverages.

Combined Impact of a Faster Self-Reported Eating Rate and Higher Dietary Energy Intake Rate on Energy Intake and Adiposity

Eating more quickly and consuming foods with a higher energy-intake-rate (EIR: kcal/min) is associated with greater energy intake and adiposity. However, it remains unclear whether individuals who eat more quickly are more likely to consume foods with higher EIR. We investigated the overlap between self-reported eating rate (SRER) and the consumption of higher EIR foods, and their combined impact on daily energy intake and adiposity in a population-based Asian cohort (n = 7011; 21-75y). Food consumption was assessed using a validated Food Frequency Questionnaire. Moderated regression with simple slope analysis was conducted to evaluate whether SRER modified the association between dietary EIR and total dietary energy intakes. Faster eaters consumed a significantly higher proportion of energy from higher EIR foods among overweight individuals, but not among normal-weight individuals. Associations between dietary EIR and total energy intake were stronger among medium (β = 15.04, 95%CI: 13.00-17.08) and fast (β = 15.69, 95%CI: 12.61-18.78) eaters, compared with slower eaters (β = 9.89, 95%CI: 5.11-14.67; p-interaction = 0.032). Higher dietary EIR also tended to be more strongly associated with BMI in fast eaters (β = 0.025, 95%CI: 0.011-0.038) than in slow eaters (β = 0.017, 95%CI: -0.007-0.040). These findings suggest that the combination of eating more quickly and selecting a greater proportion of energy from higher EIR foods (i.e., softly textured, energy dense), promoted higher dietary energy intakes and adiposity.

Diet, Physical Activity and Adiposity as Determinants of Circulating Amino Acid Levels in a Multiethnic Asian Population

Profiles of circulating amino acids have been associated with cardiometabolic diseases. We investigated the associations between dietary protein intake, physical activity and adiposity and serum amino acid profiles in an Asian population. We used data from 3009 male and female participants from the Singapore Prospective Study Program cohort. Dietary and physical activity data were obtained from validated questionnaires; anthropometric measurements were collected during a health examination; and fasting concentrations of 16 amino acids were measured using targeted LC-MS. The association between lifestyle factors and amino acid levels was modeled using multiple linear regression with adjustment for other sociodemographic and lifestyle factors and correction for multiple testing. We observed significant associations between seafood intake (β-coefficient 0.132, 95% CI 0.006, 0.257 for a 100% increment), physical activity (β-coefficient −0.096, 95% CI −0.183, −0.008 in the highest versus lowest quartile) and adiposity (BMI β-coefficient 0.062, 95% CI 0.054, 0.070 per kg/m²; waist circumference β-coefficient 0.034, 95% CI 0.031, 0.037 per cm) and branched-chain amino acid levels (expressed per-SD). We also observed significant interactions with sex for the association between meat and seafood and total intakes and BCAA levels (P for interaction 0.007), which were stronger in females than in males. Our findings suggest novel associations between modifiable lifestyle factors and amino acid levels in Asian populations.

CHI study: protocol for an observational cohort study on ageing and mental health in community-dwelling older adults

INTRODUCTION

Ageing is associated with a multitude of healthcare issues including dementia, depression, frailty, morbidity associated with chronic disease and high healthcare utilisation. With Singapore's population projected to age significantly over the next two decades, it has become increasingly important to understand the disease burden and etiological process among older adults. The Community Health and Intergenerational study aims to holistically examine ageing in place by investigating the resilience and vulnerability factors of the ageing process in the biological, psychological and social domains within the environment.

METHODS AND ANALYSIS

Using a cohort multiple randomised controlled trial design, comprehensive health profiles of community-dwelling older adults will be collected. The objective is to recruit 1000 participants (aged 60-99 years) living in the western region of Singapore within a period of 3 years (2018-2020). Assessments include basic sociodemographic, physical health and function (cardiac, oral and blood profiles and visual function), cognitive functioning, daily functioning, physical fitness, emotional state, free-flowing speech, sleep quality, social connectedness, caregiver burden, intergenerational communication, quality of life, life satisfaction, attitudes to ageing and gratitude and compassion. Results from the cohort will enable future studies to identify at-risk groups and develop interventions to improve the physical and mental health and quality of life of older adults.

ETHICS AND DISSEMINATION

Approval of the cohort study by the National University of Singapore Institutional Review Board (NUS-IRB Reference code: H-17-047) was obtained on 12 October 2017. Written consent will be obtained from all participants. Findings from the cohort study will be disseminated by publication of peer-reviewed manuscripts, presentations at scientific meetings and conferences with local stakeholders.

Association Between Self-Reported Eating Rate, Energy Intake, and Cardiovascular Risk Factors in a Multi-Ethnic Asian Population

Eating faster is associated with greater body mass index (BMI), but less is known about the relationships between eating rate, energy intake, body composition, and cardio-metabolic risk factors in different Asian ethnic groups. Using data from the Singapore Multi-Ethnic Cohort (n = 7011; 21-75 y), we investigated associations between self-reported eating rate (SRER), with energy intake, body composition, blood pressure, and blood lipids. SRER and lifestyle was assessed using interviewer-administered questionnaires. Multivariable models were used to examine the associations of SRER with energy intake, body composition, blood pressure, and blood lipids after adjusting for covariates. General and abdominal overweight were defined as BMI ≥ 23 kg/m² and waist circumference > 90cm (men) and > 80cm (women), respectively. On average, faster eaters (vs. slower eaters) consumed 105kcal/day more (p = 0.034), had ~5kg higher body weight (p < 0.001), 1.3 kg/m² higher BMI (p < 0.001), and 3.1cm larger waist-circumference (p < 0.001). Faster eaters had significantly higher blood pressure, circulating triglycerides, and total-to-high-density lipoprotein cholesterol ratio than slower eaters. Faster eaters were twice as likely to develop general (multivariable-OR: 2.2;95%CI,1.8-2.6; p < 0.001), and abdominal (OR:1.8;95%CI, 1.5-2.2; p < 0.001) overweight than slower eaters. This association was observed across all subgroups by age, sex, and ethnicity. Findings suggest that SRER is a robust behavioral marker for increased risk of higher energy intake, obesity, and poor cardio-metabolic health, and a modifiable behavioral risk-factor for obesity prevention.

The effect of coffee consumption on insulin sensitivity and other biological risk factors for type 2 diabetes: a randomized placebo-controlled trial

BACKGROUND

In observational studies, coffee consumption has been consistently associated with a lower risk of type 2 diabetes mellitus. Trials examining the effect of coffee consumption on glucose metabolism have been limited by the use of surrogate insulin sensitivity indices, small sample sizes, lack of blinding, and short follow-up duration.

OBJECTIVES

We aimed to overcome limitations of previously conducted coffee trials in a randomized placebo-controlled trial of the effect of coffee consumption on insulin sensitivity.

METHODS

We conducted a 24-wk randomized placebo-controlled trial in 126 overweight, non-insulin sensitive (HOMA-IR ≥1.30), Chinese, Malay, and Asian-Indian males and females aged 35-69 y. Participants were randomly assigned to receive 4 cups of instant regular coffee (n = 62) or 4 cups of a coffee-like placebo beverage (n = 64) per day. The primary outcome was the amount of glucose metabolized per kilogram of body weight per minute (Mbw) assessed during steady-state conditions with a hyperinsulinemic euglycemic clamp. Secondary outcomes included other clamp-based insulin sensitivity measures, biological mediators of insulin sensitivity, and measures of fasting glucose metabolism.

RESULTS

Coffee consumption did not significantly change insulin sensitivity compared with placebo (percentage mean difference in Mbw = 4.0%; 95% CI: -8.3, 18.0%; P = 0.53). Furthermore, no significant differences in fasting plasma glucose (2.9%; 95% CI: -0.4, 6.3%; P = 0.09) or biological mediators of insulin resistance, such as plasma adiponectin (2.3%; 95% CI: -1.4, 6.2%; P = 0.22), were observed between coffee and placebo groups over 24 wk of intervention. Participants in the coffee arm experienced a loss of fat mass (FM) (-3.7%; 95% CI: -6.3, -1.1%; P = 0.006) and reduction in urinary creatinine concentrations (-21.2%; 95% CI: -31.4, -9.5%; P = 0.001) compared with participants in the placebo arm over 24 wk of intervention.

CONCLUSIONS

Consuming 4 cups/d of caffeinated coffee for 24 wk had no significant effect on insulin sensitivity or biological mediators of insulin resistance but was associated with a modest loss of FM and reduction in urinary creatinine concentrations.This trial was registered at clinicaltrials.gov as NCT01738399. Registered on November 28, 2012. Trial sponsor: Nestlé Research, Lausanne, Switzerland. Trial site: National University of Singapore.

Factors associated with the severity of hypertension among Malaysian adults

High blood pressure is a worldwide problem and major global health burden. Whether alone or combined with other metabolic diseases, high blood pressure increases the risk of cardiovascular disease. This study is a secondary data analysis from the National Health and Morbidity Survey 2015, a population-based study that was conducted nationwide in Malaysia using a multi-stage stratified cluster sampling design. A total of 15,738 adults ≥18-years-old were recruited into the study, which reports the prevalence of hypertension stages among adults in Malaysia using the JNC7 criteria and determinants of its severity. The overall prevalence of raised blood pressure was 66.8%, with 45.8% having prehypertension, 15.1% having Stage 1 hypertension, and 5.9% having Stage 2 hypertension. In the multivariate analysis, a higher likelihood of having prehypertension was observed among respondents with advancing age, males (OR = 2.74, 95% CI: 2.41-3.12), Malay ethnicity (OR = 1.21, 95% CI: 1.02-1.44), lower socioeconomic status, and excessive weight. The factors associated with clinical hypertension (Stages 1 and 2) were older age, rural residency (Stage 1 OR = 1.22, Stage 2 OR = 1.28), Malay ethnicity (Stage 2 OR = 1.64), diabetes (Stage 2 OR = 1.47), hypercholesterolemia (Stage 1 OR = 1.34, Stage 2 OR = 1.82), being overweight (Stage 1 OR = 2.86, Stage 2 OR = 3.44), obesity (Stage 1 OR = 9.01, Stage 2 OR = 13.72), and lower socioeconomic status. Almost 70% of Malaysian adults are at a risk of elevated blood pressure. The highest prevalence was in the prehypertension group, which clearly predicts a future incurable burden of the disease. Public health awareness, campaigns through mass and social media, and intervention in the work place should be a priority to control this epidemic.

A Healthy Asian A Posteriori Dietary Pattern Correlates with A Priori Dietary Patterns and Is Associated with Cardiovascular Disease Risk Factors in a Multiethnic Asian Population

Background

Healthful dietary patterns are associated with cardiovascular disease risk factors in Western populations. However, a consistent healthful dietary pattern across major Asian ethnic groups has yet to be identified.

Objective

We aimed to identify a posteriori dietary patterns for Chinese, Malay, and Indian ethnic groups in an urban Asian setting, compare these with a priori dietary patterns, and ascertain associations with cardiovascular disease risk factors including hypertension, obesity, and abnormal blood lipid concentrations.

Methods

We used cross-sectional data from 8433 Singapore residents (aged 21-94 y) from the Multi-Ethnic Cohort study of Chinese, Malay, and Indian ethnicity. Food consumption was assessed using a validated 169-item food-frequency questionnaire. With the use of 28 food groups, dietary patterns were derived by principal component analysis, and their association with cardiovascular disease risk factors was assessed using multiple linear regression. Associations between derived patterns and a priori patterns (aHEI-2010-Alternative Healthy Eating Index-2010, aMED-alternate Mediterranean Diet, and DASH-Dietary Approaches to Stop Hypertension) were assessed, and the magnitude of associations with risk factors compared.

Results

We identified a "healthy" dietary pattern, similar across ethnic groups, and characterized by high intakes of whole grains, fruit, dairy, vegetables, and unsaturated cooking oil and low intakes of Western fast foods, sugar-sweetened beverages, poultry, processed meat, and flavored rice. This "healthy" pattern was inversely associated with body mass index (BMI; in kg/m2) (-0.26 per 1 SD of the pattern score; 95% CI: -0.36, -0.16), waist circumference (-0.57 cm; 95% CI: -0.82, -0.32), total cholesterol (-0.070 mmol/L; 95% CI: -0.091, -0.048), LDL cholesterol (-0.054 mmol/L; 95% CI: -0.074, -0.035), and fasting triglycerides (-0.22 mmol/L; 95% CI: -0.04, -0.004) and directly associated with HDL cholesterol (0.013 mmol/L; 95% CI: 0.006, 0.021). Generally, "healthy" pattern associations were at least as strong as a priori pattern associations with cardiovascular disease risk factors.

Conclusion

A healthful dietary pattern that correlated well with a priori patterns and was associated with lower BMI, serum LDL cholesterol, total cholesterol, and fasting triglyceride concentrations was identified across 3 major Asian ethnic groups.

A systematic literature review of reviews on techniques for physical activity measurement in adults: a DEDIPAC study

The links between increased participation in Physical Activity (PA) and improvements in health are well established. As this body of evidence has grown, so too has the search for measures of PA with high levels of methodological effectiveness (i.e. validity, reliability and responsiveness to change). The aim of this “review of reviews” was to provide a comprehensive overview of the methodological effectiveness of currently employed measures of PA, to aid researchers in their selection of an appropriate tool. A total of 63 review articles were included in this review, and the original articles cited by these reviews were included in order to extract detailed information on methodological effectiveness.

Self-report measures of PA have been most frequently examined for methodological effectiveness, with highly variable findings identified across a broad range of behaviours. The evidence-base for the methodological effectiveness of objective monitors, particularly accelerometers/activity monitors, is increasing, with lower levels of variability observed for validity and reliability when compared to subjective measures. Unfortunately, responsiveness to change across all measures and behaviours remains under-researched, with limited information available.

Other criteria beyond methodological effectiveness often influence tool selection, including cost and feasibility. However, researchers must be aware of the methodological effectiveness of any measure selected for use when examining PA. Although no “perfect” tool for the examination of PA in adults exists, it is suggested that researchers aim to incorporate appropriate objective measures, specific to the behaviours of interests, when examining PA in free-living environments.

Correlates of occupational, leisure and total sitting time in working adults: results from the Singapore multi-ethnic cohort

Background

Evidence on the health risks of sitting is accumulating. However, research identifying factors influencing sitting time in adults is limited, especially in Asian populations. This study aimed to identify socio-demographic and lifestyle correlates of occupational, leisure and total sitting time in a sample of Singapore working adults.

Methods

Data were collected between 2004 and 2010 from participants of the Singapore Multi Ethnic Cohort (MEC). Medical exclusion criteria for cohort participation were cancer, heart disease, stroke, renal failure and serious mental illness. Participants who were not working over the past 12 months and without data on sitting time were excluded from the analyses. Multivariable regression analyses were used to examine cross-sectional associations of self-reported age, gender, ethnicity, marital status, education, smoking, caloric intake and moderate-to-vigorous leisure time physical activity (LTPA) with self-reported occupational, leisure and total sitting time. Correlates were also studied separately for Chinese, Malays and Indians.

Results

The final sample comprised 9384 participants (54.8% male): 50.5% were Chinese, 24.0% Malay, and 25.5% Indian. For the total sample, mean occupational sitting time was 2.71 h/day, mean leisure sitting time was 2.77 h/day and mean total sitting time was 5.48 h/day. Sitting time in all domains was highest among Chinese. Age, gender, education, and caloric intake were associated with higher occupational sitting time, while ethnicity, marital status and smoking were associated with lower occupational sitting time. Marital status, smoking, caloric intake and LTPA were associated with higher leisure sitting time, while age, gender and ethnicity were associated with lower leisure sitting time. Gender, marital status, education, caloric intake and LTPA were associated with higher total sitting time, while ethnicity was associated with lower total sitting time. Stratified analyses revealed different associations within sitting domains for Indians compared to Chinese and Malays.

Conclusion

Our findings highlight the need to focus on separate domains of sitting (occupational, leisure or total) when identifying which factors determine this behavior, and that the content of intervention programs should be tailored to domain-specific sitting rather than to sitting in general. Finally, our study showed ethnic differences and therefore we recommend to culturally target interventions.

Criterion validity of the Physical Activity Scale (PAS2) in Danish adults

BACKGROUND

The Physical Activity Scale (PAS2) was developed to measure physical activity (PA) during work, transportation and leisure time, in the Danish adult population. The objective of this study was to assess the criterion validity of PAS2 against a combined accelerometer and heart rate monitor in Danish adults and to investigate if the criterion validity differed by socio-demographic factors and body mass index.

METHOD

A total of 330 Danish adults (mean age = 46.7 years, 38.5% men) participating in the Health2008 study completed the PAS2 questionnaire and wore a combined accelerometer and heart rate sensor for seven days. Average daily estimates from PAS2 were categorised into time spent in sedentary behaviour, light PA, moderate PA and vigorous PA and were compared to the objective measures.

RESULTS

PAS2 accounted for 19.5 hours/day on average. Time spent in sedentary behaviour, light and moderate-intensity PA was weakly correlated with objective data (polychoric correlation coefficients (PCC): 0.18-0.20), whereas vigorous intensity PA was moderately correlated (PCC: 0.54, p = 0.04). Mean bias was -2.3 hours/day (95% limits of agreement (LoA): -9.04 to 4.34) for sedentary behaviour, 1.68 hours/day (LoA: 8.02 to -4.62) for light activity, 0.55 hours/day (LoA: 3.37 to -2.26) for moderate activity and 0.12 hours/day (LoA: 0.57 to 0.33) for vigorous activity. Criterion validity was lower in women, in participants who were above 40 years, overweight, had short education and were unemployed.

CONCLUSIONS

PAS2 overestimated time spent on light, moderate and vigorous intensity PA and underestimated time spent on sedentary behaviour. Validity differed by key socio-demographic characteristics.

Correlates of Agreement between Accelerometry and Self-reported Physical Activity

Supplemental digital content is available in the text.

Purpose

Understanding factors that influence accurate assessment of physical activity (PA) and sedentary behavior (SB) is important to measurement development, epidemiologic studies, and interventions. This study examined agreement between self-reported (International Physical Activity Questionnaire—Long Form [IPAQ-LF]) and accelerometry-based estimates of PA and SB across six countries and identified correlates of between-method agreement.

Methods

Self-report and objective (accelerometry-based) PA and SB data were collected in 2002–2011 from 3865 adult participants in eight cities from six countries (Belgium, Czech Republic, Denmark, Spain, United Kingdom, and United States). Between-method relative agreement (correlation) and absolute disagreement (mean difference between conceptually and intensity-matched IPAQ-LF and accelerometry-based PA and SB variables) were estimated. Also, sociodemographic characteristics and PA patterns were examined as correlates of between-method agreement.

Results

Observed relative agreement (relationships of IPAQ-LF with accelerometry-based PA and SB variables) was small to moderate (r = 0.05–0.37) and was moderated by sociodemographic (age, sex, weight status, and education) and behavioral (PA-type) factors. The absolute disagreement was large, with participants self-reporting higher PA intensity and total time in moderate-to-vigorous-intensity PA than accelerometry. Also, self-reported sitting time was lower than accelerometry-based sedentary behavior. After adjusting for sociodemographic and behavioral factors, the absolute disagreement between pairs of IPAQ-LF and accelerometry-based PA variables remained significantly different across cities/countries.

Conclusions

Present findings suggest systematic cultural and/or linguistic and sociodemographic differences in absolute agreement between the IPAQ-LF and the accelerometry-based PA and SB variables. These results have implications for the interpretation of international PA and SB data and correlate/determinant studies. They call for further efforts to improve such measures.

Consumption of Red Meat, but Not Cooking Oils High in Polyunsaturated Fat, Is Associated with Higher Arachidonic Acid Status in Singapore Chinese Adults

High arachidonic acid (AA; 20:4n-6) status may have adverse effects on inflammation and risk of cardiovascular diseases. Concerns about high intake of n-6 polyunsaturated fatty acids (PUFAs) are based on the premise that endogenous conversion from linoleic acid (LA; 18:2n-6) is an important source of AA, but few population-based studies have investigated dietary determinants of AA status. In this study, we examined habitual food consumption in relation to plasma concentrations of AA and other PUFAs in population-based studies. We used cross-sectional data from 269 healthy, ethnic Chinese participants (25–80 years old) with contrasting intakes of fish and red meat from the Singapore Prospective Study Program and 769 healthy participants (44–74 years old) from the Singapore Chinese Health Study as a validation set. Multivariable linear regression was used to examine PUFA intake (% energy) and food sources of PUFA (fish, red meat, poultry, soy and cooking oils) in relation to plasma PUFAs (AA, LA, dihomo-gamma-linolenic acid (DGLA; 20:3n-6), alpha-linolenic acid (ALA; 18:3n-3), eicosapentaenoic acid (EPA; 20:5n-3), and docosahexaenoic acid (DHA; 22:6n-3)) concentrations. Higher intake of red meat was associated with higher plasma AA concentrations. High intake of PUFA or PUFA-rich oils was associated with higher plasma ALA but not with plasma AA. Higher intakes of soy were associated with higher ALA and fish with higher DHA and EPA concentrations. These associations were statistically significant (p < 0.05) in both studies. Red meat consumption, but not PUFA or PUFA-rich cooking oil, was associated with circulating AA suggesting that intake of pre-formed AA rather than LA is an important determinant of AA status. A diet high in fish, soy products and polyunsaturated cooking oil, and low in red meat may be associated with an optimal plasma profile of PUFA in this Chinese population.

Validation of the SQUASH Physical Activity Questionnaire in a Multi-Ethnic Population: The HELIUS Study

PURPOSE

To investigate the reliability and validity of the SQUASH physical activity (PA) questionnaire in a multi-ethnic population living in the Netherlands.

METHODS

We included participants from the HELIUS study, a population-based cohort study. In this study we included Dutch (n = 114), Turkish (n = 88), Moroccan (n = 74), South-Asian Surinamese (n = 98) and African Surinamese (n = 91) adults, aged 18-70 years. The SQUASH was self-administered twice to assess test-re-test reliability (mean interval 6-7 weeks) and participants wore an accelerometer and heart rate monitor (Actiheart) to enable assessment of construct validity.

RESULTS

We observed low test-re-test reliability; Intra class correlation coefficients ranged from low (0.05 for moderate/high intensity PA in African Surinamese women) to acceptable (0.78 for light intensity PA in Moroccan women). The discrepancy between self-reported and measured PA differed on the basis of the intensity of activity: self-reported light intensity PA was lower than measured but self-reported moderate/high intensity PA was higher than measured, with wide limits of agreement. The discrepancy between questionnaire and Actiheart measures of moderate intensity PA did not differ between ethnic minority and Dutch participants with correction for relevant confounders. Additionally, the SQUASH overestimated the number of participants meeting the Dutch PA norm; Cohen's kappas for the agreement were poor, the highest being 0.30 in Dutch women.

CONCLUSION

We found considerable variation in the test-re-test reliability and validity of self-reported PA with no consistency based on ethnic origin. Our findings imply that the SQUASH does not provide a valid basis for comparison of PA between ethnic groups.

Accelerometry and physical activity questionnaires - a systematic review

Background

The aim of this study is to review accelerometer wear methods and correlations between accelerometry and physical activity questionnaire data, depending on participant characteristics.

Methods

We included 57 articles about physical activity measurement by accelerometry and questionnaires. Criteria were to have at least 100 participants of at least 18 years of age with manuscripts available in English. Accelerometer wear methods were compared. Spearman and Pearson correlation coefficients between questionnaires and accelerometers and differences between genders, age categories, and body mass index (BMI) categories were assessed.

Results

In most investigations, requested wear time was seven days during waking hours and devices were mostly attached on hips with waist belts. A minimum of four valid days with wear time of at least ten hours per day was required in most studies. Correlations (r = Pearson, ρ = Spearman) of total questionnaire scores against accelerometer measures across individual studies ranged from r = 0.08 to ρ = 0.58 (P < 0.001) for men and from r = −0.02 to r = 0.49 (P < 0.01) for women. Correlations for total physical activity among participants with ages ≤65 ranged from r = 0.04 to ρ = 0.47 (P < 0.001) and from r = 0.16 (P = 0.02) to r = 0.53 (P < 0.01) among the elderly (≥65 years). Few studies investigated stratification by BMI, with varying cut points and inconsistent results.

Conclusion

Accelerometers appear to provide slightly more consistent results in relation to self-reported physical activity among men. Nevertheless, due to overall limited consistency, different aspects measured by each method, and differences in the dimensions studied, it is advised that studies use both questionnaires and accelerometers to gain the most complete physical activity information.

Electronic supplementary material

The online version of this article (doi:10.1186/s12889-016-3172-0) contains supplementary material, which is available to authorized users.

Determinants of individuals' participation in integrated chronic disease screening in Singapore

BACKGROUND

A large pool of patients with chronic diseases remains undiagnosed globally and in Singapore. We explored factors associated with participation in a health screening exercise, using revealed preference, that is, actual attendance, to understand why people remain undiagnosed with chronic diseases.

METHODS

A cross-sectional, community-based sample of Singapore residents was invited to participate in home interviews, and subsequently to attend centre-based health screening, between 2004 and 2007. Determinants of health screening participation were identified using logistic regression models based on Andersen's Behavioral Model.

RESULTS

Of the 6366 participants who completed health interview, 4092 attended the health screening, while 2274 did not. Older age, Chinese or Indian ethnicity, higher education levels, greater intake of monounsaturated fat, greater transport and leisure-time physical activity were the key predisposing factors associated with greater health screening participation. Greater family cohesion was the key associated enabling factor, while previous diagnosis of dyslipidaemia or musculoskeletal conditions, absence of previously diagnosed diabetes or hypertension and lower perceived physical health were the associated need factors.

CONCLUSIONS

Our study suggests that ethnicity, education, family cohesion, healthy behaviour patterns and perceived physical health status were key determinants of health screening participation. Enhancing the cultural competence of preventive health services may help increase participation of these groups in screening efforts and reduce the proportions of undiagnosed chronic disease in the community.

Validation of the long international physical activity questionnaire: Influence of age and language region

Objective

Little is known about the influence of age, gender and language on the measurement properties of the long International Physical Activity Questionnaire (IPAQ). The aim was to validate the long IPAQ in adults aged 18–84 in the German-, French- and Italian-speaking parts of Switzerland, focusing on differences between gender, age groups and language regions.

Methods

This cross-sectional study was conducted in the frame of SAPALDIA (Swiss Cohort Study on Air Pollution and Lung and Heart Disease in Adults) in 2011. 346 participants (54.6% women, mean age 54.6 years) wore an Actigraph GT3X accelerometer during 8 days and completed the IPAQ. IPAQ and accelerometer data on total physical activity and on different intensities as well as sitting time were compared using Spearman correlations and Bland–Altman plots.

Results

Correlations were highest for vigorous physical activity (r = 0.41) and sitting time (r = 0.42). Significant gender differences were apparent for leisure-time physical activity (men: r = 0.35 versus women: r = 0.57, p = 0.012) and for sitting time (men: r = 0.28 versus women: r = 0.53, p = 0.007). Differences between age groups were present for sitting time (youngest: r = 0.72 versus middle: r = 0.36, p < 0.001; youngest versus oldest: r = 0.34, p = 0.001). Differences between language regions were present for vigorous physical activity (German: r = 0.28 versus Italian: r = 0.53, p = 0.033). IPAQ overestimated physical activity but underestimated sitting time.

Conclusion

The long IPAQ showed moderate validity similar to other studies when compared to accelerometer data in a diverse sample of individuals. Some sex, age and regional differences were observed but do not seem to limit its applicability in population sub groups.

•

We assessed the validity of the long IPAQ focusing on age and language differences.

•

The IPAQ showed moderate validity against accelerometers.

•

Correlations were highest for vigorous physical activity and for sitting time.

•

We observed only limited sex, age and regional differences regarding validity.

•

However, these do not limit the applicability of the IPAQ in specific sub groups.

Physical activity using wrist-worn accelerometers: comparison of dominant and non-dominant wrist

The purpose of this study was to determine whether there is a difference in physical activity assessment between a wrist-worn accelerometer at the dominant or non-dominant arm. The secondary purpose was to assess the concurrent validity of measures of physical activity from the wrist-worn accelerometer and the waist-worn accelerometer. Forty adults wore three accelerometers simultaneously, one on the waist and one each on the non-dominant wrist and dominant wrist, respectively, for 24 consecutive hours of free-living conditions. Data were uploaded from the monitor to a computer following a 1-day test period. There were no significant differences in physical activity when comparing the dominant versus the non-dominant wrist, regardless of axis (P>0·05). Mean daily accelerometer output data from both wrists were strongly correlated with average counts per minute from the ActiGraph worn around the waist (r = 0·88, P<0·001). Findings suggest that the choice to wear the accelerometer on the non-dominant or dominant wrist has no impact on results. Data from this study contribute to the knowledge of how to best assess physical activity habits.

Smaller size of high metabolic rate organs explains lower resting energy expenditure in Asian-Indian Than Chinese men

BACKGROUND

In Singapore, the obesity prevalence is disproportionately higher in the Asian-Indians and Malays than the Chinese. Lower resting energy expenditure (REE) may be a contributory factor.

OBJECTIVE

We explored the association between ethnicity and REE in Chinese, Asian-Indian and Malay men living in Singapore and determined the influence of body composition, mass/volume of high metabolic rate organs, represented by brain volume and trunk fat-free mass (FFM), and physical activity on ethnic differences.

DESIGN

Two hundred and forty-four men from Singapore (n=100 Chinese, 70 Asian-Indians and 74 Malays), aged 21-40 years and body mass index of 18.5-30.0 kg m(-2), were recruited in this cross-sectional study. REE was assessed by indirect calorimetry and body composition by dual-energy X-ray absorptiometry. Brain volume was measured by magnetic resonance imaging. Physical activity was assessed by the Singapore Prospective Study Program Physical Activity Questionnaire.

RESULTS

REE was significantly lower in Asian-Indians compared with that in Chinese after adjusting for body weight. FFM (total, trunk and limb) and total fat mass were important predictors of REE across all ethnic groups. Brain volume was positively associated with REE only in Malays. Moderate and vigorous physical activity was positively associated with REE only in Asian-Indians and Malays. The difference in REE between Asian-Indians and Chinese was attenuated but remained statistically significant after adjustment for total FFM (59±20 kcal per day), fat mass (67±20 kcal per day) and brain volume (54±22 kcal per day). The association between REE and ethnicity was no longer statistically significant after total FFM was replaced by trunk FFM (which includes heart, liver, kidney and spleen) but not when it was replaced by limb FFM (skeletal muscle).

CONCLUSIONS

We have demonstrated a lower REE in Asian-Indians compared with Chinese who may contribute to the higher rates of obesity in the former. This difference could be accounted for by differences in metabolically active organs.

Association of Television Viewing Time with Body Composition and Calcified Subclinical Atherosclerosis in Singapore Chinese

Objective

Sedentary behavior such as television viewing may be an independent risk factor for coronary heart disease. However, few studies have assessed the impact of television viewing time on coronary artery calcification and it remains unclear how body fat contributes to this relationship. The aim of this study is to evaluate the association between television viewing time and subclinical atherosclerosis and whether effects on visceral or subcutaneous fat may mediate any associations observed.

Methods

This was a cross-sectional study of 398 Chinese participants (192 men and 206 women) from Singapore prospective study. Participants were free from known cardiovascular diseases and underwent interview, health screening, computed tomography scans of coronary arteries and abdomen. Spearman’s correlation was used to test the correlation between television viewing time, physical activity, body composition and abdominal fat distribution. The association between television viewing time and subclinical atherosclerosis was assessed by multiple logistic regression analysis.

Results

In men, television viewing time was significantly correlated with higher body fat mass index, percent body fat, subcutaneous and visceral fat. These associations were in the same direction, but weaker and not statistically significant in women. Television viewing time (hours/day) was associated with subclinical atherosclerosis in men (odds ratio: 1.41, 95% CI: 1.03-1.93) but no significant association was observed in women (odds ratio: 0.88, 95% CI: 0.59-1.31) after adjusting for potential socio-demographic and lifestyle confounders. Further adjustments for biological factors did not affect these associations.

Conclusions

Television viewing time was associated with greater adiposity and higher subcutaneous and visceral fat in men. TV viewing time was also associated with subclinical atherosclerosis in men and the potential mechanisms underlying this association require further investigation.

Identifying Factors Associated With Dropout During Prerandomization Run-in Period From an mHealth Physical Activity Education Study: The mPED Trial

Background

The mobile phone-based physical activity education (mPED) trial is a randomized controlled trial (RCT) evaluating a mobile phone-delivered physical activity intervention for women. The study includes a run-in period to maximize the internal validity of the intervention trial, but little is known about factors related to successful run-in completion, and thus about potential threats to external validity.

Objective

Objectives of this study are (1) to determine the timing of dropout during the run-in period, reasons for dropout, optimum run-in duration, and relevant run-in components, and (2) to identify predictors of failure to complete the run-in period.

Methods

A total of 318 physically inactive women met preliminary eligibility criteria and were enrolled in the study between May 2011 and April 2014. A 3-week run-in period was required prior to randomization and included using a mobile phone app and wearing a pedometer. Cross-sectional analysis identified predictors of dropout.

Results

Out of 318 participants, 108 (34.0%) dropped out prior to randomization, with poor adherence using the study equipment being the most common reason. Median failure time was 17 days into the run-in period. In univariate analyses, nonrandomized participants were younger, had lower income, were less likely to drive regularly, were less likely to have used a pedometer prior to the study, were generally less healthy, had less self-efficacy for physical activity, and reported more depressive symptoms than randomized participants. In multivariate competing risks models, not driving regularly in the past month and not having used a pedometer prior to the study were significantly associated with failure to be randomized (P=.04 and .006, respectively), controlling for age, race/ethnicity, education, shift work, and use of a study-provided mobile phone.

Conclusions

Regular driving and past pedometer use were associated with reduced dropout during the prerandomization run-in period. Understanding these characteristics is important for identifying higher-risk participants, and implementing additional help strategies may be useful for reducing dropout.

Trial Registration

ClinicalTrials.gov NCT01280812; https://clinicaltrials.gov/ct2/show/NCT01280812 (Archived by WebCite at http://www.webcitation.org/6XFC5wvrP).

Rice and noodle consumption is associated with insulin resistance and hyperglycaemia in an Asian population

High consumption of refined grains, particularly white rice, has been reported to be associated with a higher risk of type 2 diabetes. Therefore, in the present study, we evaluated the association between rice and noodle consumption and markers of glucose homeostasis, inflammation and dyslipidaemia in an Asian population. We carried out a population-based cross-sectional study in 2728 Singaporean Chinese men and women aged between 24 and 92 years. Rice and noodle intake was assessed using a validated FFQ and studied in relation to glycaemic (fasting glucose, glycated Hb, homeostasis model assessment (HOMA) index for insulin resistance (HOMA-IR) and HOMA index for β-cell function (HOMA-β)), inflammatory (plasma adiponectin and C-reactive protein (CRP)) and lipid (fasting TAG and HDL-cholesterol (HDL-C)) markers. We used multiple linear regression analyses with adjustment for total energy intake and sociodemographic, anthropometric (BMI and waist:hip ratio) and lifestyle factors. Higher rice consumption was found to be associated with higher fasting glucose concentrations (0·81 % higher values per portion increment; 95 % CI 0·09, 1·54) and HOMA-IR (4·62 %; 95 % CI 1·29, 8·07). Higher noodle consumption was also found to be significantly associated with higher fasting glucose concentrations (1·67 %; 95 % CI 0·44, 2·92), HOMA-IR (6·17 %; 95 % CI 0·49, 12·16) and fasting TAG concentrations (9·17 %; 95 % CI 3·44, 15·22). No significant association was observed between rice and noodle consumption and adiponectin, CRP and HDL-C concentrations or HOMA-β in the fully adjusted model. These results suggest that high consumption of rice and noodles may contribute to hyperglycaemia through greater insulin resistance and that this relationship is independent of adiposity and systemic inflammation.

Television screen time, but not computer use and reading time, is associated with cardio-metabolic biomarkers in a multiethnic Asian population: a cross-sectional study

Background

Recent evidence shows that sedentary behaviour may be an independent risk factor for cardiovascular diseases, diabetes, cancers and all-cause mortality. However, results are not consistent and different types of sedentary behaviour might have different effects on health. Thus the aim of this study was to evaluate the association between television screen time, computer/reading time and cardio-metabolic biomarkers in a multiethnic urban Asian population. We also sought to understand the potential mediators of this association.

Methods

The Singapore Prospective Study Program (2004–2007), was a cross-sectional population-based study in a multiethnic population in Singapore. We studied 3305 Singaporean adults of Chinese, Malay and Indian ethnicity who did not have pre-existing diseases and conditions that could affect their physical activity. Multiple linear regression analysis was used to assess the association of television screen time and computer/reading time with cardio-metabolic biomarkers [blood pressure, lipids, glucose, adiponectin, C reactive protein and homeostasis model assessment of insulin resistance (HOMA-IR)]. Path analysis was used to examine the role of mediators of the observed association.

Results

Longer television screen time was significantly associated with higher systolic blood pressure, total cholesterol, triglycerides, C reactive protein, HOMA-IR, and lower adiponectin after adjustment for potential socio-demographic and lifestyle confounders. Dietary factors and body mass index, but not physical activity, were potential mediators that explained most of these associations between television screen time and cardio-metabolic biomarkers. The associations of television screen time with triglycerides and HOMA-IR were only partly explained by dietary factors and body mass index. No association was observed between computer/ reading time and worse levels of cardio-metabolic biomarkers.

Conclusions

In this urban Asian population, television screen time was associated with worse levels of various cardio-metabolic risk factors. This may reflect detrimental effects of television screen time on dietary habits rather than replacement of physical activity.

Validity of the international physical activity questionnaire in the arctic

PURPOSE

Information about physical activity (PA) in Greenland is limited, partly because of a lack of validated instruments in countries with non-Western living conditions. We modified the long form of the International Physical Activity Questionnaire (IPAQ-L) to arctic living conditions. The aim of the study was to compare IPAQ-L estimates with combined accelerometry and heart rate monitoring (ACC + HR) in a population-based study of adult Inuit in Greenland.

METHODS

Cross-sectional data were collected by face-to-face interview and ACC + HR monitoring among Inuit (18 yr and above) in Greenland during 2005-2010 (n = 1508). PA energy expenditure (PAEE) and time spent sedentary and on PA at moderate and vigorous intensity were derived from IPAQ-L and ACC + HR. Estimates were compared using Bland-Altman agreement analysis and Spearman correlations stratified by sex, place of residence (capital, towns, and villages), and age groups.

RESULTS

Questionnaire-based PAEE was moderately correlated with objectively measured PAEE (r = 0.20-0.35, P < 0.01). Self-reported time spent at moderate- and vigorous-intensity PA and time spent sedentary were weakly correlated with the objective measure (r = 0.11-0.31). Agreement analyses showed relatively small median differences for all measures of PA; however, time spent at moderate-intensity PA was substantially overreported by IPAQ-L when including walking (>1.5 h·d, P < 0.001) but not when excluding walking.

CONCLUSIONS

The IPAQ-L adapted to arctic living conditions in Greenland had a moderate level of agreement with combined accelerometry and heart rate monitoring for total PAEE at population level, but it was less valid to measure different intensities of PA and sedentary activity. Validity did not differ markedly between rural and urban communities.

Positive experience, self-efficacy, and action control predict physical activity changes: a moderated mediation analysis

OBJECTIVES

Experiencing positive consequences of one's physical activity is supposed to facilitate further activity. This motivational outcome might be generated by an increase in perceived self-efficacy. In addition to such a mediator effect, we examine whether this applies generally or only under conditions of volitional control. For this purpose, perceived action control was considered as a putative moderator.

DESIGN AND METHOD

N = 193 students participated in a study with three measurement points in time. At baseline, positive experience with previous physical activity was measured as a predictor of physical activity. Two weeks later, self-efficacy and action control variables were assessed as putative mediator and moderator, respectively. After another 2 weeks, physical activity was measured as the outcome. A moderated mediation model was specified with baseline physical activity and sex as covariates.

RESULTS

Self-efficacy was found to mediate between initial positive experience and later physical activity, and this mediation was moderated by action control.

CONCLUSIONS

Participants' perceptions of positive experience were associated with their subsequent self-efficacy fostering physical activity. However, persons with low levels of action control did not translate positive experience into physical activity via self-efficacy.

STATEMENT OF CONTRIBUTION

What is already known on this subject? Numerous studies have shown that exercise-specific self-efficacy predicts subsequent physical activity. Prior positive experience with physical activity is suggested to be associated with exercise-specific self-efficacy. Furthermore, action control was found to be beneficial for the maintenance of physical activity. What does this study add? This study unveils the mechanisms between these social-cognitive determinants: our longitudinal results suggest that the mediation of positive experience and subsequent physical activity via self-efficacy is moderated by action control. Persons with low levels of action control did not translate positive experience into physical activity via self-efficacy.

A systematic review of reliability and objective criterion-related validity of physical activity questionnaires

Physical inactivity is one of the four leading risk factors for global mortality. Accurate measurement of physical activity (PA) and in particular by physical activity questionnaires (PAQs) remains a challenge. The aim of this paper is to provide an updated systematic review of the reliability and validity characteristics of existing and more recently developed PAQs and to quantitatively compare the performance between existing and newly developed PAQs.

A literature search of electronic databases was performed for studies assessing reliability and validity data of PAQs using an objective criterion measurement of PA between January 1997 and December 2011. Articles meeting the inclusion criteria were screened and data were extracted to provide a systematic overview of measurement properties. Due to differences in reported outcomes and criterion methods a quantitative meta-analysis was not possible.

In total, 31 studies testing 34 newly developed PAQs, and 65 studies examining 96 existing PAQs were included. Very few PAQs showed good results on both reliability and validity. Median reliability correlation coefficients were 0.62–0.71 for existing, and 0.74–0.76 for new PAQs. Median validity coefficients ranged from 0.30–0.39 for existing, and from 0.25–0.41 for new PAQs.

Although the majority of PAQs appear to have acceptable reliability, the validity is moderate at best. Newly developed PAQs do not appear to perform substantially better than existing PAQs in terms of reliability and validity. Future PAQ studies should include measures of absolute validity and the error structure of the instrument.

Comparison of two ActiGraph accelerometer generations in the assessment of physical activity in free living conditions

Background

The aim of this study was to compare physical activity measured using GT1M ActiGraph and GT3X ActiGraph accelerometers in free living conditions.

Findings

Twenty-five adults wore GT1M and GT3X Actigraph accelerometers simultaneously during a typical weekday of activity. Data were uploaded from the monitor to a computer at the end of test (one day). Previously established thresholds were used for defining time spent at each level of physical activity, physical activity was assessed at varying intensities comparing data from the two accelerometers by ANOVA and Bland and Altman statistical analysis. The concordance correlation coefficient between accelerometers at each intensity level was 0.99. There were no significant differences between accelerometers at any of the activity levels. Differences between data obtained in minutes with the GT1M accelerometer and the GT3X monitor were to 0.56, 0.36, 0.52 and 0.44% for sedentary, light, moderate and vigorous, respectively. The Bland and Altman method showed good agreement between data obtained for the two accelerometers.

Conclusions

Findings suggest that the two accelerometers provided similar results and therefore the GT3X may be used in clinical and epidemiological studies without additional calibration or validation studies.