Jean-Michel Oppert

Measuring the food environment using geographical information systems: a methodological review.

OBJECTIVEnThrough a literature review, we investigated the geographic information systems (GIS) methods used to define the food environment and the types of spatial measurements they generate.nnnDESIGNnReview study.nnnSETTINGnSearches were conducted in health science databases, including Medline/Pubmed, PsycINFO, Francis and GeoBase. We included studies using GIS-based measures of the food environment published up to 1 June 2008.nnnRESULTSnTwenty-nine papers were included. Two different spatial approaches were identified. The density approach quantifies the availability of food outlets using the buffer method, kernel density estimation or spatial clustering. The proximity approach assesses the distance to food outlets by measuring distances or travel times. GIS network analysis tools enable the modelling of travel time between referent addresses (home) and food outlets for a given transportation network and mode, and the assumption of travel routing behaviours. Numerous studies combined both approaches to compare food outlet spatial accessibility between different types of neighbourhoods or to investigate relationships between characteristics of the food environment and individual food behaviour.nnnCONCLUSIONSnGIS methods provide new approaches for assessing the food environment by modelling spatial accessibility to food outlets. On the basis of the available literature, it appears that only some GIS methods have been used, while other GIS methods combining availability and proximity, such as spatial interaction models, have not yet been applied to this field. Future research would also benefit from a combination of GIS methods with survey approaches to describe both spatial and social food outlet accessibility as important determinants of individual food behaviours.

Assessment of environmental correlates of physical activity: development of a European questionnaire

BackgroundResearch on the influence of the physical environment on physical activity is rapidly expanding and different measures of environmental perceptions have been developed, mostly in the US and Australia. The purpose of this paper is to (i) provide a literature review of measures of environmental perceptions recently used in European studies and (ii) develop a questionnaire for population monitoring purposes in the European countries.MethodsThis study was done within the framework of the EU-funded project Instruments for Assessing Levels of Physical Activity and Fitness (ALPHA), which aims to propose standardised instruments for physical activity and fitness monitoring across Europe. Quantitative studies published from 1990 up to November 2007 were systematically searched in Pubmed, Web of Science, TRIS and Geobase. In addition a survey was conducted among members of the European network for the promotion of Health-Enhancing Physical Activity (HEPA Europe) and European members of the International Physical Activity and Environment Network (IPEN) to identify published or ongoing studies. Studies were included if they were conducted among European general adult population (18+y) and used a questionnaire to assess perceptions of the physical environment. A consensus meeting with an international expert group was organised to discuss the development of a European environmental questionnaire.ResultsThe literature search resulted in 23 European studies, 15 published and 8 unpublished. In these studies, 13 different environmental questionnaires were used. Most of these studies used adapted versions of questionnaires that were developed outside Europe and that focused only on the walkability construct: The Neighborhood Environment Walkability Scale (NEWS), the abbreviated version of the NEWS (ANEWS) and the Neighborhood Quality of Life Study (NQLS) questionnaire have been most commonly used. Based on the results of the literature review and the output of the meeting with international experts, a European environmental questionnaire with 49 items was developed.ConclusionThere is need for a greater degree of standardization in instruments/methods used to assess environmental correlates of physical activity, taking into account the European-specific situation. A first step in this process is taken by the development of a European environmental questionnaire.

Measuring physical activity-related environmental factors: reliability and predictive validity of the European environmental questionnaire ALPHA

BackgroundA questionnaire to assess physical activity related environmental factors in the European population (a 49-item and an 11-item version) was created as part of the framework of the EU-funded project Instruments for Assessing Levels of PHysical Activity and fitness (ALPHA). This paper reports on the development and assessment of the questionnaires test-retest stability, predictive validity, and applicability to European adults.MethodsThe first pilot test was conducted in Belgium, France and the UK. In total 190 adults completed both forms of the ALPHA questionnaire twice with a one-week interval. Physical activity was concurrently measured (i) by administration of the long version of the International Physical Activity Questionnaire (IPAQ) by interview and (ii) by accelerometry (Actigraph™ device). After adaptations, the second field test took place in Belgium, the UK and Austria; 166 adults completed the adapted questionnaire at two time points, with minimum one-week interval. In both field studies intraclass correlation coefficients (ICC) and proportion of agreement were computed to assess the stability of the two test scores. Predictive validity was examined in the first field test by correlating the results of the questionnaires with physical activity data from accelerometry and long IPAQ-last 7 days.ResultsThe reliability scores of the ALPHA questionnaire were moderate-to good in the first field testing (ICC range 0.66 - 0.86) and good in the second field testing (ICC range 0.71 - 0.87). The proportion of agreement for the ALPHA short increased significantly from the first (range 50 - 83%) to the second field testing (range 85 - 95%). Environmental scales from both versions of the ALPHA questionnaire were significantly associated with self-reported minutes of transport-related walking, and objectively measured low intensity physical activity levels, particularly in women. Both versions were easily administered with an average completion time of six minutes for the 49-item version and less than two minutes for the short version.ConclusionThe ALPHA questionnaire is an instrument to measure environmental perceptions in relation to physical activity. It appears to have good reliability and predictive validity. The questionnaire is now available to other researchers to investigate its usefulness and applicability across Europe.

Associations of Supermarket Characteristics with Weight Status and Body Fat: A Multilevel Analysis of Individuals within Supermarkets (RECORD Study)

Purpose Previous research on the influence of the food environment on weight status has often used impersonal measures of the food environment defined for residential neighborhoods, which ignore whether people actually use the food outlets near their residence. To assess whether supermarkets are relevant contexts for interventions, the present study explored between-residential neighborhood and between-supermarket variations in body mass index (BMI) and waist circumference (WC), and investigated associations between brands and characteristics of supermarkets and BMI or WC, after adjustment for individual and residential neighborhood characteristics. Methods Participants in the RECORD Cohort Study (Paris Region, France, 2007–2008) were surveyed on the supermarket (brand and exact location) where they conducted their food shopping. Overall, 7 131 participants shopped in 1 097 different supermarkets. Cross-classified multilevel linear models were estimated for BMI and WC. Results Just 11.4% of participants shopped for food primarily within their residential neighborhood. After accounting for participants residential neighborhood, people shopping in the same supermarket had a more comparable BMI and WC than participants shopping in different supermarkets. After adjustment for individual and residential neighborhood characteristics, participants shopping in specific supermarket brands, in hard discount supermarkets (especially if they had a low education), and in supermarkets whose catchment area comprised low educated residents had a higher BMI/WC. Conclusion A public health strategy to reduce excess weight may be to intervene on specific supermarkets to change food purchasing behavior, as supermarkets are where dietary preferences are materialized into definite purchased foods.

Associations between dietary patterns, physical activity (leisure-time and occupational) and television viewing in middle-aged French adults

Diet and physical activity are considered to be major components of a healthy lifestyle. However, few studies have examined in detail the relationships between specific types of physical activity, sedentary behaviour and diet in adults. The objective of the present study was to assess differential relationships between dietary patterns, leisure-time and occupational physical activities and time spent watching television (TV), as an indicator of sedentary behaviour, in middle-aged French subjects. We performed a cross-sectional analysis using data from 1359 participants in the SUpplémentation en VItamines et Minéraux AntioXydants study, who completed a detailed physical activity questionnaire and at least six 24 h dietary records. Sex-specific dietary patterns were derived using factor analysis; their relationships with leisure-time and occupational physical activities and TV viewing were assessed using ANCOVA, after adjustment for age, educational level and smoking status. Three dietary patterns were identified in each sex. After adjustment for potential confounders, leisure-time physical activity was positively associated with a healthy food pattern in both men (P for trend < 0·01) and women (P for trend < 0·03) and negatively associated with an alcohol/meat pattern in men (P for trend < 0·01). TV viewing was positively associated with a convenience pattern in men and with a alcohol-appetiser pattern in women. In conclusion, identification of relationships between dietary patterns, physical activity and sedentary behaviour can enable identification of different types of lifestyle and should help to target at-risk groups in nutrition prevention programmes.

One-Year Changes in Energy Expenditure and Serum Leptin Following Adjustable Gastric Banding in Obese Women

Background: Weight loss is associated with a decrease in both energy expenditure and circulating leptin levels. Whether this holds true when the influence of body composition on energy expenditure and leptin is taken into account remains controversial. The aim of the study was to assess changes in resting metabolic rate (RMR) and serum leptin adjusted for body composition during surgically induced weight loss. Methods: In 36 women (age 42.7±8.7 years; BMI 47.2±8.5 kg/m2; mean±SD) undergoing laparoscopic adjustable gastric banding (LAGB) for morbid obesity, we measured RMR (by indirect calorimetry), body composition (by dual-energy X-ray absorptiometry) and serum leptin (by immunoradiometry), immediately before and 1 year after surgery. Results: 1 year after LAGB, there were significant decreases in body weight (−23.7±11.6 kg, P<0.001), fat mass (FM: −20.9±11.3 kg, P<0.0001), lean body mass (LBM: −3±5.3 kg, P=0.005), RMR (−298±309 kcal/day, P<0.0001), serum leptin (−24.0±18.4 ng/ml, P<0.0001), RMR/LBM ratio (−3.9±5.8 kcal/kg LBM/day, P<0.01) and leptin/FM ratio (−0.21±0.29 ng/kg FM/ml, P<0.001). RMR values after surgery were correctly predicted by the regression equation relating RMR to LBM and FM at baseline, whereas this was not the case for serum leptin (in relation to FM). Conclusions: Changes in RMR 1 year after LAGB were explained by changes in body composition whereas changes in serum leptin were not. The data provide no evidence for a metabolic adaptation of RMR with weight loss, but suggest that serum leptin is decreased beyond expected values based on body composition, a factor that may favor weight regain after surgically induced weight loss.

Plasma leptin and hunger ratings in healthy humans

Leptin, the ob gene product, is considered as a signal involved in the regulation of energy stores through centrally mediated effects on ingestive behavior and metabolism. To investigate the relationships between appetite-related sensations and circulating leptin in humans, 12 healthy male volunteers were served two test lunches (1200 kcal, 38% carbohydrate, 50% fat, 12% protein) with comparable palatability but resulting in different postprandial hunger ratings, and plasma leptin concentrations were monitored during 8 h after meal ingestion. Whereas postprandial hunger ratings (assessed by visual analog scales) and plasma insulin patterns differed significantly between meals, no significant difference in postprandial plasma leptin concentrations was observed between the two meals. A moderate but significant increase in mean plasma leptin was found over time. We conclude that postprandial plasma leptin concentrations do not significantly differ between two meals inducing different effects on hunger subjective feelings. These data are in agreement with a role for leptin in the regulation of energy balance as a long-term adiposity-related signal rather than a short-term meal-related factor.

Pharmacology of morphine in obese patients: clinical implications.

Morphine is an analgesic drug used to treat acute and chronic pain. Obesity is frequently associated with pain of various origins (e.g. arthritis, fibromyalgia, cancer), which increases the need for analgesic drugs. Obesity changes drug pharmacokinetics, and for certain drugs, specific modalities of prescription have been proposed for obese patients. However, scant data are available regarding the pharmacokinetics and pharmacodynamics of morphine in obesity. Prescription of morphine depends on pain relief but the occurrence of respiratory adverse effects correlates with obesity, and is not currently taken into account. Variations in the volume of distribution, elimination half-life and oral clearance of morphine, as well as recent advances in the respective roles of drug-metabolizing enzymes, catechol-O-methyltransferase and the μ opioid receptor in morphine pharmacokinetics and pharmacodynamics, may contribute to differences between obese and non-obese patients. In addition, drug-drug interactions may alter the disposition of morphine and its glucuronide metabolites, which may either increase the risk of adverse effects or reduce drug efficacy.

Leisure-time and occupational physical activity in relation to cardiovascular risk factors and eating habits in French adults

OBJECTIVEnTo investigate the relationships of two main physical activity domains (during leisure and at work) with cardiovascular risk factors and eating habits.nnnDESIGNnCross-sectional study.nnnSETTINGnPreventive medicine centre.nnnSUBJECTSnIn 5478 adults (32% women, aged 20-80 years) who consecutively underwent a standardised health examination, leisure-time physical activity (LTPA; i.e. non-sport leisure and sport activities), occupational physical activity (OPA) and eating habits were assessed by self-administered questionnaires. We analysed sex-specific relationships of LTPA and OPA (in quartiles) with (1) various cardiovascular risk factors and (2) eating habits using analysis of variance and logistic regression, respectively.nnnRESULTSnIn both genders, with and without adjustment for education in addition to age, LTPA was associated negatively with body mass index, body fat, waist circumference, resting heart rate, diastolic blood pressure and triglycerides, and positively associated with high-density lipoprotein cholesterol (all P < or = 0.005). OPA adjusted for age only was positively associated with most cardiovascular risk factors but these associations were not significant after further adjustment on education (except for waist circumference in women). Age- and education-adjusted LTPA was associated with increased frequency of consumption of fruits (odds ratio (OR) = 2.05, 95% confidence interval (CI) 1.68-2.52 in men; OR = 1.90, 95% CI 1.41-2.05 in women) and vegetables (OR = 1.81, 95% CI 1.48-2.21 in men; OR = 2.22, 95% CI 1.66-2.97 in women).nnnCONCLUSIONSnThe data emphasise the favourable associations of LTPA, a modifiable behaviour, with various cardiovascular risk factors and healthy eating habits. The results also suggest that the relationships of OPA with cardiovascular risk factors depend, at least in part, on socio-economic status as reflected by educational level.

Obesity-related polymorphisms and their associations with the ability to regulate fat oxidation in obese Europeans: the NUGENOB study.

Both obesity and insulin resistance have been related to low fat oxidation rates, which may be genetically determined. The association between variation in fat oxidation rates among obese subjects and genotype was studied for 42 common single‐nucleotide polymorphisms (SNPs) in 26 candidate genes for fat oxidation, insulin resistance, and obesity, including FTO. Energy expenditure (EE) and fat oxidation were measured with indirect calorimetry during fasting and 3 h after a high fat load containing 95 energy% of fat (60% saturated fat, energy content 50% of estimated resting EE) in 722 obese subjects (541 women, 181 men) from 8 European centers. After adjustment for center and gender, −178 A>C CD36 (rs2232169) (P = 0.02), −22510 C>G SLC6A14 (women, rs2011162) (P = 0.03), and T690S C>G PCSK1 (rs6235) (P = 0.02) were related to a reduced fat oxidation, whereas 17 C>G SREBF1 (17 C>G) (P = 0.01) was related to increased fat oxidation in the fasting state. The ability to increase fat oxidation after a high fat load was increased in subjects with −174 G>C IL6 (rs1800795) (P = 0.01). Effect sizes range from 1.1 to 3.1% differences in fat oxidation (expressed as % of EE). FTO rs9939609 was not related to fat oxidation. At the same time, the results are not adjusted for multiple testing, thus none of the associations can be considered statistically significant. The results should therefore only be considered as leads to new hypotheses about effects of specific genetic polymorphisms on fasting and postprandial fat oxidation.