Costs and Clinical Consequences of Compliance with COPD GOLD Recommendations or National Guidelines Compared with Current Clinical Practice in Belgium, Germany, Sweden, and the United States.

Purpose: The objective of this study was to assess the clinical and cost benefits of treating patients with chronic obstructive pulmonary disease (COPD) according to global and national guidelines compared to real-life clinical practice in the United States and three European countries (Belgium, Germany, Sweden). Patients and Methods: A cost-consequence model was developed to compare current prescribing patterns with two alternative scenarios, the first aligned with the Global Initiative for Chronic Obstructive Lung Disease (GOLD 2022) recommendations and the second with national guidelines. Costs and clinical outcomes were modeled for these alternative scenarios over a time horizon of one year, based on real-world evidence and health insurance data. Results: Current clinical practice in each of the countries was inconsistent with published recommendations. A redistribution to prescribing patterns according to global and national recommendations led to a substantial decrease in the use of inhaled corticosteroid (ICS) containing therapies of more than 80% and 44%, respectively. There was a reduced incidence of up to 16% of mild-to-moderate pneumonia and up to 29% of severe pneumonia. Exacerbations decreased across all countries apart from Sweden, where a small increase in the rate of exacerbations was due to the redistribution of some patients currently undergoing inhaled triple therapy to non-ICS-containing therapies. Adapting treatment to recommendations could provide potential cost savings of up to 13% in estimated annual direct costs, resulting predominantly from the reduction in cost of healthcare resource use, including hospitalization associated with treating incident pneumonia, particularly severe pneumonia. Cost savings for prevalent adult patients with COPD on long-acting inhaler therapy ranged from €31 to €675 per patient per year. Conclusion: Redistribution of COPD patients from current clinical practice to treatment according to published recommendations would provide clinical benefits and substantial cost savings.

Cost-consequence analysis of COPD treatment according to NICE and GOLD recommendations compared with current clinical practice in the UK.

OBJECTIVES: The objective of this study was to model the clinical and economic impact of adapting current clinical practice in the management of patients with chronic obstructive pulmonary disease (COPD) to treatment according to national and international guideline recommendations. DESIGN: Treatment mapping was undertaken to hypothetically redistribute patients from current clinical practice, representing actual prescribing patterns in the UK, to an alternative recommendation-based treatment scenario, representing prescribing in accordance with either National Institute for Health and Care Excellence (NICE) guidance [NG115] or Global Initiative for Chronic Obstructive Lung Disease (GOLD) 2020 strategy. SETTING: Primary care practices in the UK (1-year time horizon). PARTICIPANTS: Adults with COPD undergoing long-acting inhaler maintenance therapy in the UK (N=1 067,531). INTERVENTIONS: Inhaler maintenance therapy. OUTCOME MEASURES: Costs and clinical outcomes (type of treatment, rates of moderate and/or severe exacerbations, and mild-to-moderate and/or severe pneumonia events) were modelled for the two alternative pathways. RESULTS: Compared with current clinical practice, treating patients according to NICE guidance resulted in an estimated annual reduction in expenditure of £46.9 million, and an estimated annual reduction in expenditure of over £43.7 million when patients were treated according to GOLD 2020 strategy. Total cost savings of up to 8% annually could be achieved by treatment of patients according to either of these recommendations. Cost savings arose from a reduction in the rates of pneumonia, with an associated decrease in costs associated with antibiotic use and hospitalisation. Savings were achieved overall despite a small increase in the rate of exacerbations due to the redistribution of certain patients currently undergoing triple inhaled therapy to therapies not containing inhaled corticosteroids. CONCLUSION: Redistribution of patients with COPD from current clinical practice to treatment according to published recommendations would provide substantial cost savings over the first year.

Cost-Consequences Analysis of Increased Utilization of Triple-Chamber-Bag Parenteral Nutrition in Preterm Neonates in Seven European Countries.

The safety of parenteral nutrition (PN) remains a concern in preterm neonates, impacting clinical outcomes and health-care-resource use and costs. This cost-consequence analysis assessed national-level impacts of a 10-percentage point increase in use of industry-prepared three-chamber bags (3CBs) on clinical outcomes, healthcare resources, and hospital budgets across seven European countries. A ten-percentage-point 3CB use-increase model was developed for Belgium, France, Germany, Italy, Portugal, Spain, and the UK. The cost-consequence analysis estimated the impact on compounding error harm and bloodstream infection (BSI) rates, staff time, and annual hospital budget. Of 265,000 (52%) preterm neonates, 133,000 (52%) were estimated to require PN. Baseline compounding methods were estimated as 43% pharmacy manual, 16% pharmacy automated, 22% ward, 9% outsourced, 3% industry provided non-3CBs, and 7% 3CBs. A modeled increased 3CB use would change these values to 39%, 15%, 18%, 9%, 3%, and 17%, respectively. Modeled consequences included -11.6% for harm due to compounding errors and -2.7% for BSIs. Labor time saved would equate to 41 specialized nurses, 29 senior pharmacists, 26 pharmacy assistants, and 22 senior pediatricians working full time. Budget impact would be a €8,960,601 (3.4%) fall from €260,329,814 to €251,369,212. Even a small increase in the use of 3CBs in preterm neonates could substantially improve neonatal clinical outcomes, and provide notable resource and cost savings to hospitals.

Cost-Effectiveness of Take-Home Naloxone for the Prevention of Overdose Fatalities among Heroin Users in the United Kingdom.

BACKGROUND: Heroin overdose is a major cause of premature death. Naloxone is an opioid antagonist that is effective for the reversal of heroin overdose in emergency situations and can be used by nonmedical responders. OBJECTIVE: Our aim was to assess the cost-effectiveness of distributing naloxone to adults at risk of heroin overdose for use by nonmedical responders compared with no naloxone distribution in a European healthcare setting (United Kingdom). METHODS: A Markov model with an integrated decision tree was developed based on an existing model, using UK data where available. We evaluated an intramuscular naloxone distribution reaching 30% of heroin users. Costs and effects were evaluated over a lifetime and discounted at 3.5%. The results were assessed using deterministic and probabilistic sensitivity analyses. RESULTS: The model estimated that distribution of intramuscular naloxone, would decrease overdose deaths by around 6.6%. In a population of 200,000 heroin users this equates to the prevention of 2,500 premature deaths at an incremental cost per quality-adjusted life year (QALY) gained of £899. The sensitivity analyses confirmed the robustness of the results. CONCLUSIONS: Our evaluation suggests that the distribution of take-home naloxone decreased overdose deaths by around 6.6% and was cost-effective with an incremental cost per QALY gained well below a £20,000 willingness-to-pay threshold set by UK decision-makers. The model code has been made available to aid future research. Further study is warranted on the impact of different formulations of naloxone on cost-effectiveness and the impact take-home naloxone has on the wider society.

Use of opioid substitution therapies in the treatment of opioid use disorder: results of a UK cost-effectiveness modelling study.

AIMS: This study investigated the cost-effectiveness of buprenorphine maintenance treatment (BMT) and methadone maintenance treatment (MMT) vs no opioid substitution therapy (OST) for the treatment of opioid use disorder, from the UK National Health Service (NHS)/personal social services (PSS) and societal perspectives over 1 year. METHODS: Cost-effectiveness of OST vs no OST was evaluated by first replicating and then expanding an existing UK health technology assessment model. The expanded model included the impact of OST on infection rates of human immunodeficiency virus (HIV) and hepatitis C virus (HCV) infection. RESULTS: Versus no OST, incremental cost-effectiveness ratios (ICERs) for BMT and MMT were £13,923 and £14,206 per quality-adjusted life year (QALY), respectively, from a NHS/PSS perspective. When total costs (NHS/PSS and societal) are considered, there are substantial savings associated with adopting OST; these savings are in excess of £14,032 for BMT vs no OST and £17,174 for MMT vs no OST over 1 year. This is primarily driven by a reduction in victim costs. OST treatment also impacted other aspects of criminality and healthcare resource use. LIMITATIONS: The model's 1-year timeframe means long-term costs and benefits, and the influence of changes over time are not captured. CONCLUSIONS: OST can be considered cost-effective vs no OST from the UK NHS/PSS perspective, with a cost per QALY well below the UK's willingness-to-pay threshold. There were only small differences between BMT and MMT. The availability of two or more cost-effective options is beneficial to retaining patients in OST programs. From a societal perspective, OST is estimated to save over £14,032 and £17,174 per year for BMT and MMT vs no OST, respectively, due to savings in victim costs. Further work is required to fully quantify the clinical and health economic impacts of different OST formulations and their societal impact over the long-term.

Estimation of Free-Living Energy Expenditure by Heart Rate and Movement Sensing: A Doubly-Labelled Water Study.

BACKGROUND: Accurate assessment of energy expenditure (EE) is important for the study of energy balance and metabolic disorders. Combined heart rate (HR) and acceleration (ACC) sensing may increase precision of physical activity EE (PAEE) which is the most variable component of total EE (TEE). OBJECTIVE: To evaluate estimates of EE using ACC and HR data with or without individual calibration against doubly-labelled water (DLW) estimates of EE. DESIGN: 23 women and 23 men (22-55 yrs, 48-104 kg, 8-46%body fat) underwent 45-min resting EE (REE) measurement and completed a 20-min treadmill test, an 8-min step test, and a 3-min walk test for individual calibration. ACC and HR were monitored and TEE measured over 14 days using DLW. Diet-induced thermogenesis (DIT) was calculated from food-frequency questionnaire. PAEE (TEE ÷ REE ÷ DIT) and TEE were compared to estimates from ACC and HR using bias, root mean square error (RMSE), and correlation statistics. RESULTS: Mean(SD) measured PAEE and TEE were 66(25) kJ·day(-1)·kg(-1), and 12(2.6) MJ·day(-1), respectively. Estimated PAEE from ACC was 54(15) kJ·day(-1)·kg(-1) (p<0.001), with RMSE 24 kJ·day(-1)·kg(-1) and correlation r = 0.52. PAEE estimated from HR and ACC+HR with treadmill calibration were 67(42) and 69(25) kJ·day(-1)·kg(-1) (bias non-significant), with RMSE 34 and 20 kJ·day(-1)·kg(-1) and correlations r = 0.58 and r = 0.67, respectively. Similar results were obtained with step-calibrated and walk-calibrated models, whereas non-calibrated models were less precise (RMSE: 37 and 24 kJ·day(-1)·kg(-1), r = 0.40 and r = 0.55). TEE models also had high validity, with biases <5%, and correlations r = 0.71 (ACC), r = 0.66-0.76 (HR), and r = 0.76-0.83 (ACC+HR). CONCLUSIONS: Both accelerometry and heart rate may be used to estimate EE in adult European men and women, with improved precision if combined and if heart rate is individually calibrated.

Energy balance and physical demands during an 8-week arduous military training course.

This study assessed soldier's physical demands and energy balance during the Section Commanders' Battles Course (SCBC). Forty male soldiers were monitored during the 8-week tactics phase of the SCBC. Energy expenditure was measured using the doubly labeled water method. Cardiovascular strain (heart rate) and physical activity (using triaxial accelerometer) were also monitored. Average sized portions of meals were weighed, with all recipes and meals entered into a dietary analysis program to calculate the calorie content. Energy expenditure averaged 19.6 ± 1.8 MJ · d(-1) in weeks 2 to 3 and 21.3 ± 2.0 MJ · d(-1) in weeks 6 to 7. Soldiers lost 5.1 ± 2.6 kg body mass and body fat percent decreased from 23 ± 4% to 19 ± 5%. This average weight loss equates to an estimated energy deficit of 2.69 MJ · d(-1). The Army provided an estimated 14.0 ± 2.2 MJ · d(-1) in weeks 2 to 3 and 15.7 ± 2.2 MJ · d(-1) in weeks 6 to 7. Although this provision adheres to the minimum requirement of 13.8 MJ · d(-1) set by Army regulations, soldiers were in a theoretical 5.6 MJ · d(-1) energy deficit. The physical demands of SCBC were high, and soldiers were in energy deficit resulting in loss in body mass; primarily attributed to a loss in fat mass.

Two new meal- and web-based interactive food frequency questionnaires: validation of energy and macronutrient intake.

BACKGROUND: Meal-Q and its shorter version, MiniMeal-Q, are 2 new Web-based food frequency questionnaires. Their meal-based and interactive format was designed to promote ease of use and to minimize answering time, desirable improvements in large epidemiological studies. OBJECTIVE: We evaluated the validity of energy and macronutrient intake assessed with Meal-Q and MiniMeal-Q as well as the reproducibility of Meal-Q. METHODS: Healthy volunteers aged 20-63 years recruited from Stockholm County filled out the 174-item Meal-Q. The questionnaire was compared to 7-day weighed food records (WFR; n=163), for energy and macronutrient intake, and to doubly labeled water (DLW; n=39), for total energy expenditure. In addition, the 126-item MiniMeal-Q was evaluated in a simulated validation using truncated Meal-Q data. We also assessed the answering time and ease of use of both questionnaires. RESULTS: Bland-Altman plots showed a varying bias within the intake range for all validity comparisons. Cross-classification of quartiles placed 70%-86% in the same/adjacent quartile with WFR and 77% with DLW. Deattenuated and energy-adjusted Pearson correlation coefficients with the WFR ranged from r=0.33-0.74 for macronutrients and was r=0.18 for energy. Correlations with DLW were r=0.42 for Meal-Q and r=0.38 for MiniMeal-Q. Intraclass correlations for Meal-Q ranged from r=0.57-0.90. Median answering time was 17 minutes for Meal-Q and 7 minutes for MiniMeal-Q, and participants rated both questionnaires as easy to use. CONCLUSIONS: Meal-Q and MiniMeal-Q are easy to use and have short answering times. The ranking agreement is good for most of the nutrients for both questionnaires and Meal-Q shows fair reproducibility.

Maternal physical activity and insulin action in pregnancy and their relationships with infant body composition.

OBJECTIVE: We sought to assess the association between maternal gestational physical activity and insulin action and body composition in early infancy. RESEARCH DESIGN AND METHODS: At 28-32 weeks' gestation, pregnant women participating in an observational study in Sweden underwent assessments of height, weight, and body composition, an oral glucose tolerance test, and 10 days of objective physical activity assessment. Thirty mothers and infants returned at 11-19 weeks postpartum. Infants underwent assessments of weight, length, and body composition. RESULTS: Early insulin response was correlated with total physical activity (r = -0.47; P = 0.007). Early insulin response (r = -0.36; P = 0.045) and total physical activity (r = 0.52; P = 0.037) were also correlated with infant fat-free mass. No maternal variable was significantly correlated with infant adiposity. CONCLUSIONS: The relationships between maternal physical activity, insulin response, and infant fat-free mass suggest that physical activity during pregnancy may affect metabolic outcomes in the mother and her offspring.

Comparison of the physical demands of single-sex training for male and female recruits in the British Army.

This study compared the physical demands and progression of basic training for male and female British Army recruits in single-sex platoons. Thirty male and 30 female recruits were monitored for energy expenditure (EE) (doubly labeled water), physical activity (3-dimensional accelerometry) and cardiovascular strain (percent heart rate reserve) during 6 weeks over the 14-week course. First time pass rate was similar for male (60%) and female (57%) recruits. Average daily percent heart rate reserve (female 31 +/- 4%; male 32 +/- 5%), physical activity levels (female 2.2 +/- 0.2; male 2.3 +/- 0.2) and percentage improvements in 2.4-km run time (female 10 +/- 4%; male 10 +/- 5%) were similar for both sexes (p > 0.05), although male recruits had 12% higher physical activity counts (p < 0.01). Although the absolute physical demands of basic training were greater for male recruits, the relative cardiovascular strain experienced was similar between sexes.

Active-Q: validation of the web-based physical activity questionnaire using doubly labeled water.

BACKGROUND: Increased use of the Internet provides new opportunities for collecting data in large studies. The aim of our new Web-based questionnaire, Active-Q, is to assess total physical activity and inactivity in adults. Active-Q assesses habitual activity during the past year via questions in four different domains: (1) daily occupation, (2) transportation to and from daily occupation, (3) leisure time activities, and (4) sporting activities. OBJECTIVE: The objective of our study is to validate Active-Q's energy expenditure estimates using the doubly labeled water (DLW) method, and to assess the reproducibility of Active-Q by comparing the results of the questionnaire completed by the same group on two occasions. METHODS: The validity and reproducibility of Active-Q were assessed in a group of 37 individuals, aged 20 to 65 years. Active-Q was distributed via email to the participants. The total energy expenditure of the participants was assessed using DLW for 11 consecutive days. RESULTS: The median time to complete Active-Q was 6.1 minutes. The majority of participants (27/37, 73%) reported that the questionnaire was "easy" or "very easy" to answer. On average, Active-Q overestimated the total daily energy expenditure by 440 kJ compared with the DLW. The Spearman correlation between the two methods was r = 0.52 (P < .001). The intraclass correlation coefficient for total energy expenditure between the results of Active-Q completed on two occasions was 0.83 (95% CI 0.73-0.93). CONCLUSIONS: Active-Q is a valid and reproducible method of assessing total energy expenditure. It is also a user-friendly method and suitable for Web-based data collection in large epidemiological studies.

Estimation of daily energy expenditure in pregnant and non-pregnant women using a wrist-worn tri-axial accelerometer.

BACKGROUND: Few studies have compared the validity of objective measures of physical activity energy expenditure (PAEE) in pregnant and non-pregnant women. PAEE is commonly estimated with accelerometers attached to the hip or waist, but little is known about the validity and participant acceptability of wrist attachment. The objectives of the current study were to assess the validity of a simple summary measure derived from a wrist-worn accelerometer (GENEA, Unilever Discover, UK) to estimate PAEE in pregnant and non-pregnant women, and to evaluate participant acceptability. METHODS: Non-pregnant (N = 73) and pregnant (N = 35) Swedish women (aged 20-35 yrs) wore the accelerometer on their wrist for 10 days during which total energy expenditure (TEE) was assessed using doubly-labelled water. PAEE was calculated as 0.9×TEE-REE. British participants (N = 99; aged 22-65 yrs) wore accelerometers on their non-dominant wrist and hip for seven days and were asked to score the acceptability of monitor placement (scored 1 [least] through 10 [most] acceptable). RESULTS: There was no significant correlation between body weight and PAEE. In non-pregnant women, acceleration explained 24% of the variation in PAEE, which decreased to 19% in leave-one-out cross-validation. In pregnant women, acceleration explained 11% of the variation in PAEE, which was not significant in leave-one-out cross-validation. Median (IQR) acceptability of wrist and hip placement was 9(8-10) and 9(7-10), respectively; there was a within-individual difference of 0.47 (p<.001). CONCLUSIONS: A simple summary measure derived from a wrist-worn tri-axial accelerometer adds significantly to the prediction of energy expenditure in non-pregnant women and is scored acceptable by participants.

Physical activity, sedentary behaviors, and estimated insulin sensitivity and secretion in pregnant and non-pregnant women.

BACKGROUND: Overweight and obesity during pregnancy raise the risk of gestational diabetes and birth complications. Lifestyle factors like physical activity may decrease these risks through beneficial effects on glucose homeostasis. Here we examined physical activity patterns and their relationships with measures of glucose homeostasis in late pregnancy compared to non-pregnant women. METHODS: Normal weight and overweight women without diabetes (N = 108; aged 25-35 years) were studied; 35 were pregnant (in gestational weeks 28-32) and 73 were non-pregnant.Insulin sensitivity and ß-cell response were estimated from an oral glucose tolerance test. Physical activity was measured during 10-days of free-living using a combined heart rate sensor and accelerometer. Total (TEE), resting (REE), and physical activity (PAEE) energy expenditure were measured using doubly-labeled water and expired gas indirect calorimetry. RESULTS: Total activity was associated with reduced first-phase insulin response in both pregnant (Regression r2 = 0.11; Spearman r = -0.47; p = 0.007) and non-pregnant women (Regression r2 = 0.11 Spearman; r = -0.36; p = 0.002). Relative to non-pregnant women, pregnant women were estimated to have secreted 67% more insulin and had 10% lower fasting glucose than non-pregnant women. Pregnant women spent 13% more time sedentary, 71% less time in moderate-to-vigorous intensity activity, had 44% lower objectively measured total activity, and 12% lower PAEE than non-pregnant women. Correlations did not differ significantly for any comparison between physical activity subcomponents and measures of insulin sensitivity or secretion. CONCLUSIONS: Our findings suggest that physical activity conveys similar benefits on glucose homeostasis in pregnant and non-pregnant women, despite differences in subcomponents of physical activity.

Accuracy and validity of a combined heart rate and motion sensor for the measurement of free-living physical activity energy expenditure in adults in Cameroon.

BACKGROUND: The increasing burden of non-communicable diseases in sub-Saharan Africa (SSA) warrants rigorous studies of contributing lifestyle factors. Combined heart rate (HR) and movement monitoring make it possible to objectively measure physical activity in free-living individuals. We examined the validity of a combined HR and motion sensor in estimating physical activity energy expenditure (PAEE) in free-living adults in rural and urban Cameroon compared with doubly-labelled water (DLW) as criterion. METHODS: PAEE was measured in 33 free-living rural and urban dwellers by DLW over 7 consecutive days. Simultaneously, the combined sensor recorded HR and uni-axial acceleration. Individual HR vs PAEE calibration was done by a step test. Branched equation modelling was used to estimate PAEE from HR and acceleration. Validity and accuracy of prediction were expressed as mean bias and root mean square error (RMSE). Agreement was analysed using Bland and Altman limits of agreement (LOA). RESULTS: There was no significant mean bias between PAEE estimated from the combined sensor or measured by DLW [mean bias (standard error): -5.4 (5.1) kJ/kg/day; P = 0.3; RMSE = 29.3 kJ/kg/day]. The bias doubled for group compared with individual calibration of HR [-9.1 (5.0) kJ/kg/day, P = 0.08]. PAEE prediction was more accurate in urban compared with rural volunteers. The 95% LOAs between predicted and measured PAEE were ∼50-60 kJ/kg/day above or below perfect agreement. CONCLUSIONS: Combined HR and movement sensing is a valid method for estimating free-living PAEE on group level in adults in SSA.

Health, fitness, and responses to military training of officer cadets in a Gulf Cooperation Council country.

OBJECTIVE: To quantify the health, fitness, and physiological responses to military training of Officer Cadets from a Gulf Cooperation Council country. METHODS: One hundred and nineteen Officer Cadets volunteered; body composition, core body temperature, aerobic fitness, hydration status (urine osmolality), cardiovascular strain, physical activity (3-dimensional accelerometry), and energy expenditure (doubly labelled water) were measured over 5-days of Basic Training (BT), Army Training (AT), Navy Training (NT), and Air Force Training (AFT). RESULTS: There were no differences between courses for body mass index (mean all courses: 24.1 +/- 4.1 kg x m2) or peak core body temperature (mean all courses: 38.1 +/- 0.4 degrees C) (p > 0.05). AT body fat (19.8 +/- 3.6%) and BT VO2 max (36.8 +/- 11.6 mL x kg(-1) x min(-1)) were lower than the other courses (BT, 26.1 +/- 8.1; NT, 26.0 +/- 6.0; AFT, 24.7 +/- 6.1%) and (AT, 44.8 +/- 9.6; NT, 45.0 +/- 7.5; AFT, 44.6 +/- 5.2 mL x kg(-1) x min(-1)), respectively (p < 0.05). NT urine osmolality (979 +/- 90 mOsmol x kg(-1)) was similar to BT (946 +/- 181 mOsmol x kg(-1) p > 0.05) but lower in AT (868 +/- 144 mOsmol x kg(-1), p < 0.05) and AFT (883 +/- 121 mOsmol x kg(-1), p < 0.05). Cardiovascular strain during NT (22 +/- 5% HRR) was lower than other courses (range, 25 +/- 4-29 +/- 3% Heart Rate Reserve) (p < 0.05). Physical activity level during AFT (1.70 +/- 0.18 AU) was lower than other courses (range, 1.86 +/- 0.21-1.92 +/- 0.18 AU) (p > 0.05). CONCLUSION: Positive developments were apparent from BT leading into other courses. Potential exists to increase physical training volume on all courses, which may improve participants' aerobic fitness, body composition, and health.

Physical activity energy expenditure of adolescents in India.

Physical activity (PA) has rarely been quantified in adolescent populations undergoing economic transition; therefore relationships with disease still remain uncertain. This study assessed whether absolute PA energy expenditure (PAEE), PAEE/kg, and PAEE/kg(FFM) could be accurately estimated using accelerometry and a questionnaire in Indian adolescents and how these values compared to those of other populations. PAEE was assessed using doubly labeled water (DLW) in 30 adolescents from Chennai, India, over seven consecutive days, simultaneous with the measurement of PA using accelerometry and a previous-week recall questionnaire. Accelerometry counts (regression analysis) and questionnaire data were used to estimate PAEE; estimates were cross-validated using the Bland-Altman method. Accelerometry data and DLW-derived PAEE were visually compared to values from four North American and European populations. For boys, 49% of the variance in DLW-derived PAEE was explained with an equation including accelerometry counts and fat-free mass (FFM). Questionnaire-derived estimates did not contribute to the explained variance in DLW derived PAEE. The group-level PA of these Indian adolescents was successfully assessed using accelerometry, but not questionnaire. DLW-derived PAEE/kg(FFM) (mean (s.d.): 53.0 (27.5) kJ/kg(FFM)/day) was lower in this group than other adolescent populations in Europe and similar to those in North America. Additionally, four boys and none of the girls accumulated ≥60 min/day of accelerometry-derived moderate intensity activity, indicating low levels of PAEE and PA in these adolescents. Further research is necessary to investigate the association between PA and health outcomes in Indian adolescents.

Predicting physical activity energy expenditure using accelerometry in adults from sub-Sahara Africa.

Lack of physical activity may be an important etiological factor in the current epidemiological transition characterized by increasing prevalence of obesity and chronic diseases in sub-Sahara Africa. However, there is a dearth of data on objectively measured physical activity energy expenditure (PAEE) in this region. We sought to develop regression equations using body composition and accelerometer counts to predict PAEE. We conducted a cross-sectional study of 33 adult volunteers from an urban (n = 16) and a rural (n = 17) residential site in Cameroon. Energy expenditure was measured by doubly labeled water (DLW) over a period of seven consecutive days. Simultaneously, a hip-mounted Actigraph accelerometer recorded body movement. PAEE prediction equations were derived using accelerometer counts, age, sex, and body composition variables, and cross-validated by the jack-knife method. The Bland and Altman limits of agreement (LOAs) approach was used to assess agreement. Our results show that PAEE (kJ/kg/day) was significantly and positively correlated with activity counts from the accelerometer (r = 0.37, P = 0.03). The derived equations explained 14-40% of the variance in PAEE. Age, sex, and accelerometer counts together explained 34% of the variance in PAEE, with accelerometer counts alone explaining 14%. The LOAs between DLW and the derived equations were wide, with predicted PAEE being up to 60 kJ/kg/day below or above the measured value. In summary, the derived equations performed better than existing published equations in predicting PAEE from accelerometer counts in this population. Accelerometry could be used to predict PAEE in this population and, therefore, has important applications for monitoring population levels of total physical activity patterns.

Year-round high physical activity levels in agropastoralists of Bolivian Andes: results from repeated measurements of DLW method in peak and slack seasons of agricultural activities.

By the repeated use of the doubly labeled water method (DLW), this study aimed to investigate (1) the extent of changes in energy expenditure and physical activity level (PAL) in response to increased agricultural work demands, and (2) whether the seasonal work demands induce the changes in the fairly equitable division of work and similarity of energy needs between men and women observed in our previous study (Phase 1 study; Kashiwazaki et al., 1995: Am J Clin Nutr 62: 901-910). In a rural small agropastoral community of the Bolivian Andes, we made the follow-up study (Phase 2, 14 adults; a time of high agricultural activity) of the Phase 1 study (12 adults; a time of low agricultural activity). In the Phase 2 study, both men and women showed very high PAL (mean+/-SD), but there was no significant difference by sex (men; 2.18 +/- 0.23 (age; 64 +/- 11 years, n = 7), women; 2.26 +/- 0.25 (63 +/- 10 years, n = 7)). The increase of PAL by 11% (P = 0.023) in the Phase 2 was equally occurred in both men and women. The factorial approach underestimated PAL significantly by approximately 15% (P < 0.05). High PAL throughout the year ranging on average 2.0 and 2.2 was attributable to everyday tasks for subsistence and domestic works undertaking over 9-11 h (men spent 2.7 h on agricultural work and 4.7 h on animal herding, whereas women spent 7.3 h almost exclusively on animal herding). The seasonal increase in PAL was statistically significant, but it was smaller than those anticipated from published reports. A flexible division of labor played an important role in the equitable energetic increase in both men and women.

Is it possible to assess free-living physical activity and energy expenditure in young people by self-report?

BACKGROUND: It is unclear whether it is possible to accurately estimate physical activity energy expenditure (PAEE) by self-report in youth. OBJECTIVE: We assessed the validity and reliability of 4 self-reports to assess PAEE and time spent at moderate and vigorous intensity physical activity (MVPA) over the previous week in British young people between 4 and 17 y of age. DESIGN: PAEE and MVPA were derived from the Children's Physical Activity Questionnaire, Youth Physical Activity Questionnaire, and Swedish Adolescent Physical Activity Questionnaire; a lifestyle score indicative of habitual activity was derived from the Child Heart and Health Study in England Questionnaire. These data were compared with criterion methods, PAEE, and MVPA derived from simultaneous measurements by doubly labeled water and accelerometry in 3 age groups: 4-5 y (n = 27), 12-13 y (n = 25), and 16-17 y (n = 24). Validity was assessed by using Spearman correlations and the Bland-Altman method, and reliability was assessed by using intraclass correlation coefficients. RESULTS: The strength of association between questionnaire and criterion methods varied (r = 0.09 to r = 0.46). Some questionnaires were able to accurately assess group-level PAEE and MVPA for some age groups, but the error was large for individual-level estimates throughout. Reliability of the Youth Physical Activity Questionnaire and Child Heart and Health Study in England Questionnaire was good (intraclass correlation coefficient: 0.64-0.92). CONCLUSIONS: Absolute PAEE and MVPA estimated from these self-reports were not valid on an individual level in young people, although some questionnaires appeared to rank individuals accurately. Age (the outcome of interest) and whether individual or group-level estimates are necessary will influence the best choice of self-report method when assessing physical activity in youth.

Validity of impedance-based predictions of total body water as measured by 2H dilution in African HIV/AIDS outpatients.

Measurements of body composition are crucial in identifying HIV-infected patients at risk of malnutrition. No information is available on the validity of indirect body composition methods in African HIV-infected outpatients. Our first aim was to test the validity of fifteen published equations, developed in whites, African-Americans and/or Africans who were or not HIV-infected, for predicting total body water (TBW) from bioelectrical impedance analysis (BIA) in HIV-infected patients. The second aim was to develop specific predictive equations. Thirty-four HIV-infected patients without antiretroviral treatment and oedema at the beginning of the study (age 39 (SD 7) years, BMI 18.7 (SD3.7) kg/m2, TBW 30.4 (SD7.2) kg) were measured at inclusion then 3 and 6 months later. In the resulting eighty-eight measurements, we compared TBW values predicted from BIA to those measured by 2H dilution. Range of bias values was 0.1-4.3 kg, and errors showed acceptable values (2.2-3.4 kg) for fourteen equations and a high value (10.4) for one equation. Two equations developed in non-HIV-infected subjects showed non-significant bias and could be used in African HIV-infected patients. In the other cases, poor agreement indicated a lack of validity. Specific equations developed from our sample showed a higher precision of TBW prediction when using resistance at 1000 kHz (1.7 kg) than at 50 kHz (2.3 kg), this latter precision being similar to that of the valid published equations (2.3 and 2.8 kg). The valid published or developed predictive equations should be cross-validated in large independent samples of African HIV-infected patients.