Association between organic food consumption and metabolic syndrome: cross-sectional results from the NutriNet-Santé study

Purpose

Metabolic syndrome (MetS), a multicomponent condition, is a cardiovascular disease predictor. Although exposure to agricultural pesticides has been suggested as a potential contributor to the rising rates of obesity, type 2 diabetes, and other features of metabolic disorders, no studies have focused on the association between consumption of organic food (produced without synthetic pesticides) and MetS. We aimed to investigate the cross-sectional association between organic food consumption and MetS in French adults to determine whether it would be worth conducting further studies, particularly large prospective and randomised trials.

Methods

A total of 8174 participants from the NutriNet-Santé study who attended a clinical visit and completed an organic food frequency questionnaire were included in this cross-sectional analysis. We evaluated the association between the proportion of organic food in the diet (overall and by food group) and MetS using Poisson regression models while adjusting for potential confounders.

Results

Higher organic food consumption was negatively associated with the prevalence of MetS: adjusted prevalence ratio was 0.69 (95% CI 0.61, 0.78) when comparing the third tertile of proportion of organic food in the diet with the first one (p value <0.0001). Higher consumption of organic plant-based foods was also related to a lower probability of having MetS. In addition, when stratifying by lifestyle factors (nutritional quality of the diet, smoking status, and physical activity), a significant negative association was detected in each subgroup (p values <0.05), except among smokers.

Conclusions

Our results showed that a higher organic food consumption was associated with a lower probability of having MetS. Additional prospective studies and randomised trials are required to ascertain the relationship between organic food consumption and metabolic disorders.

     

Psychometric properties of the Korean version of the effort–reward imbalance questionnaire: a study in a petrochemical company

Objective To evaluate the criterion validity, factorial validity, and internal consistency of Korean version of effort–reward imbalance (ERI) for the scales of effort, reward, and overcommitment as well as to examine the effect of psychosocial factors on physical and mental illness among petroleum refinery workers in South Korea. Methods The Korean version of ERI questionnaire was constructed using the translation and back-translation technique, and its psychometric properties were explored among 908 male workers in a large petroleum refinery in South Korea in 2002. Cronbach’s alpha coefficient was used to test internal consistency. An exploratory factor analysis was conducted on all items of the instrument. Confirmatory factor analyses were conducted on each dimension of effort, reward and overcommitment. Physical and mental health was measured by self-rated health (SF-8). The lowest tertiles of the scores were defined as illness. Multiple logistic regression models were used to test the effect of job stress on the physical and mental health (criterion validity of ERI scales). Results The Cronbach’s alpha coefficients for effort, reward, and overcommitment were 0.71, 0.86, and 0.75, respectively, indicating satisfactory internal consistency. Exploratory factor analysis found three latent factors, which closely corresponded to the theoretical structure of the ERI model. Acceptable construct validity was shown using confirmatory factor analysis. The highest tertile of effort–reward ratio was significantly associated with physical illness (OR 2.4, 95% CI 1.7–3.6) and mental illness (OR 2.9, 95% CI 2.0–4.2), compared to lower tertiles. Overcommitment was significantly associated with mental illness, but not with physical illness. Conclusions These findings contribute to the validity and reliability of the Korean ERI questionnaire. Importantly, in the context of a rapid change in the labour market, the lack of reciprocity between efforts and rewards at work is strongly associated with self-rated physical and mental health.     

The relationship between antibiotic therapy in early childhood and the symptoms of allergy in children aged 6–8 years — the questionnaire study results

Introduction

Studies based on the ISAAC questionnaire suggest a correlation between the use of antibiotics and the prevalence of asthma and allergy in children aged 6–7 years. The number of courses of antibiotic therapy is an important factor.

Objectives

To investigate the relationship between the use of antibiotics during the first years of life and the prevalence of allergy and asthma among children (aged 6–8 years) in the urban population of Poland.

Materials and Methods

A survey-based study with a self-completed questionnaire. The respondents were parents of children aged 6-8 years living in Warszawa, Poland. 1461 completed questionnaires were collected.

Results

Asthma was declared in 4.3% of the children. Wheezing and/or sibilant rhonchi within 12 months before the study was observed in 13.5% of the cases. Asthma medication was taken by 21.8% of the children. Allergic rhinitis was declared in 18.7% of the children. Problems with sneezing, rhinorrhea, and nasal congestion not associated with cold or fever were observed in 40.7% of the children. The analysis of the odds ratios between the use of antibiotics and the symptoms of allergic diseases revealed a clear correlation. The highest odds ratio was observed between the completion of over three courses of antibiotic therapy prior to the age of 12 months and the declaration of one of the following: asthma (OR = 5.59, 95% CI: 2.6–12.01), wheezing and/or sibilant rhonchi (OR = 4.68, 95% CI: 3.01–7.27) and taking medicines for breathlessness (OR = 5.12, 95% CI: 3.42–7.68).

Conclusions

There is a direct relationship between antibiotic use in the first 3 years of life and asthma and allergy symptoms in children aged 6–8 years old.     

Are the stages of change relevant for the development and implementation of a web-based tailored alcohol intervention? A cross-sectional study

ABSTRACT: BACKGROUND: Computer-tailored programs are a promising tool to stimulate health behavior change, such as reducing alcohol intake. Yet more research is needed to assess whether groups differing in their motivational level to change may need different types of feedback. Furthermore, it is unknown whether motivational level may also determine reactions to computer-tailored interventions. Our aim is to identify the potential relevance of the application of the stages of change concept in the development and implementation of alcohol interventions. METHODS: A web-based instrument was used to disseminate a questionnaire and to provide tailored feedback messages among adults in the Netherlands (N=170; 96 females). Motivational level was assessed by the stage of change construct. The survey furthermore assessed alcohol consumption, attitude, social influence, self-efficacy, and program evaluation (i.e., survey items, tailored advice, layout and functionality of the program). The Least Significant Difference method was used to compare people in different stages of change with regard to psychosocial determinants of drinking behavior and program evaluation. RESULTS: Of the respondents, 34.1% (n=58) reported no intention to drink healthily in the foreseeable future (precontemplation), 22.9% (n=39) intended to improve their drinking behavior in the near future (contemplation/preparation) and 42.9% (n=73) reported to currently adhere to the Dutch alcohol consumption guidelines (action/maintenance). When comparing the three groups, people in the action or maintenance stage reported the lowest number of pros of drinking alcohol, having most healthy drinking role models and the highest levels of self-efficacy regarding healthy drinking in difficult situations, whereas precontemplators reported to receive the least social support regarding healthy drinking. In general, the intervention was positively evaluated, but it seemed to be most appreciated by contemplators and preparators. CONCLUSIONS: Stage-matched interventions may be useful to encourage people to reduce their alcohol intake. Different factors seem to be important for people in different motivational stages. Longitudinal studies are needed to determine whether these factors also predict stage transition. The intervention could be optimized by tailoring the feedback messages more precisely to the needs of people in different motivational stages, for example by applying the different processes of change.     

Does non-responder bias have a significant effect on the results in a postal questionnaire study?

Background and aim: In epidemiological questionnaire studies results can be influenced by non-responder bias. However, in respiratory epidemiology this has been analysed in very few recently published papers. The aim of our paper is to assess if the results found in our previous postal questionnaire study in an adult population in Northern Finland were biased by non-response. Methods: A random sample of 385 persons from the 1284 non-responders in a previous postal questionnaire study was examined. The same questionnaire as in the original study was again mailed to these persons, and those still not answering were contacted by phone. Results: Totally 183 complete answers (48%) were collected. Lack of interest (56%) and forgetting to mail the response letter (22%) were the most common reasons to non-response. Typical non-responders were young men and current smokers who less frequently reported respiratory symptoms in exercise and asthma than the responders in the original study. Answers collected by phone gave for some questions higher prevalence rates than postal answers. Conclusion: Firstly, in this population the response rate (83.6%) in the original study was high enough to provide reliable results for respiratory symptoms and diseases, only the prevalence of current smoking was biased by non-response. Secondly, the methods used for collecting responses in a non-response study may influence the results.     

Optimizing the design of web-based questionnaires – experience from a population-based study among 50,000 women

Background Web-questionnaires are an important tool for future epidemiological research because these allow for rapid and cost-efficient assembly of self-reported information on risk factors and health outcomes. However, to achieve high response rates it is essential to accommodate factors that prevent drop out and so insure validity of future studies. We aim to study how socio-demographic variables as well as design issues such as the ordering and level of difficulty (Easy-to-hard vs. Hard-to-easy) of questions in a web-questionnaire affects the probability of drop out and non-response. Method In 2003 we invited 47,859 women participating in an ongoing prospective study to a follow-up using a web-based mode. Two versions of the questionnaire existed, varying in level of difficulty (Easy-to-hard vs. Hard-to-easy). We report drop out (proportion non-completers) between groups defined by level of difficulty and estimated adjusted risk differences. Results The drop out differs significantly depending on the order of the questions in the web-questionnaire. The socio-demographic pattern among lurkers (participants that enter, start responding to, but do not complete a web-questionnaire) differs from that among completers of web-questionnaires. Conclusions An additional 6% units of completers – persons initiating and completing the questionnaire – can be obtained by considering the ordering of questions. A group uniquely identified in web-surveys,␣as lurkers are potentially easier to persuade to complete an already started web-questionnaire compared to a non-responder. Lurkers thus constitute a unique opportunity of decreasing the drop out rate and therefore merit future research.     

Does socio-demographic status influence the effect of pollens and molds on hospitalization for asthma? Results from a time-series study in 10 Canadian cities

PURPOSE: Social status influences asthma morbidity but the mechanisms are not well understood. To determine if sociodemographics influence the susceptibility to ambient aeroallergens, we determined the association between daily hospitalizations for asthma and daily concentrations of ambient pollens and molds in 10 large Canadian cities. METHODS: Daily time-series analyses were performed and results were adjusted for day of the week, temperature, barometric pressure, relative humidity, ozone, carbon monoxide, sulfur dioxide, and nitrogen dioxide. Results were then stratified by age, gender, and neighborhood family education and income. RESULTS: There appeared to be age and gender interactions in the relation between aeroallergens and asthma. An increase in basidiomycetes equivalent to its mean value, about 300/m3, increased asthma admissions for younger males (under 13 years of age) by 9.3% (95% CI, 4.8%, 13.8%) vs. 4.2% (95% CI, - 0.1%, 8.5%) for older males. The reverse was true among females with increased effect in the older age group: 2.3% (95% CI, 1.2%, 5.8%) in those under 13 years vs. 7.1% (95% CI, 4.1%, 10.1%) for older females. Associations were seen between aeroallergens and asthma hospitalization in the lowest but not the highest education group. CONCLUSIONS: Our results suggest that younger males and those within less educated families may be more vulnerable to aeroallergens as reflected by hospitalization for asthma.     

Association between smoking and paracoccidioidomycosis: a case-control study in the State of Espírito Santo,Brazil

Paracoccidioidomycosis, the main systemic mycosis in Brazil, requires long-term, high-cost treatment and leaves serious sequelae in the lungs, the organ most frequently affected and further subject to aggressive external risk factors like smoking. The influence of tobacco and alcohol consumption on chronic paracoccidioidomycosis was investigated using a case-control study. Data on occupation, place of residence, and living habits were obtained from 70 cases and 180 controls residing in the same geographic areas. The risk of becoming ill was 14 times greater among smokers and 3.6 times greater among individuals with an alcohol intake of more than 50 g/day. Logistic regression showed as significant variables: tobacco consumption for more than 20 years (OR = 10.1), smoking manufactured (not hand-rolled) cigarettes (OR = 4.8), and alcohol intake > 50 g/day (OR = 2.9). Cases who smoked 20 or more cigarettes/day became ill on average eight years before others (p = 0.002). Alcohol intake > 50 g/day had no statistically significant impact on age at onset of illness (p = 0.78). The study concludes that smoking stands as an important risk factor for the development of chronic paracoccidioidomycosis. As for alcoholism, there is evidence that it acts as a co-factor, together with smoking.     

The association between socio-demographic factors and leisure-time physical activity in the Pró-Saúde Study

This study evaluated the relationship between socio-demographic variables and leisure-time physical activity (LTPA). A baseline survey questionnaire was completed by 4,030 employees. LPTA was assessed as engagement in physical activities during the previous two weeks. The metabolic cost of LTPA was calculated based on frequency and amount of time participating in physical activities, assigning weekly metabolic equivalents (METs) to each activity. Odds ratios (OR) to express the relationship between socio-demographic factors and LTPA were estimated from multinomial regression models. The questions used to evaluate LTPA presented moderate reproducibility, with kappa correlation coefficients ranging from 0.45 to 0.88. Prevalence of LTPA was higher among men (52.2% men; 40.8% women). For both men and women, higher educational level and higher income were both associated with engaging in LPTA, this relationship being stronger for the highest tercile of METs as compared to physical inactivity. Men were more engaged in LTPA, and there was a strong association between LTPA and socio-demographic variables for both genders.     

Is questionnaire information valid in the study of a chronic disease such as diabetes? The Nord-Tr?ndelag diabetes study.

STUDY OBJECTIVE--The aim was to validate information about diabetes mellitus collected by questionnaire in a large epidemiological survey. DESIGN--Questions on diabetes diagnosis, medical treatment for diabetes, diabetes duration, and hypertension treatment were selected from the Nord-Trøndelag health survey questionnaires. One of the municipalities was selected for the validation study. SETTING--The health survey 1984-86 addressed all inhabitants > or = 20 years of age in Nord-Trøndelag county, Norway; 76,885 (90.3%) of the eligible population participated in answering the question on diabetes. PARTICIPANTS--All inhabitants in the municipality answering "yes" to the question on diabetes (n = 169) and the persons with the same sex born closest before and after each diabetic patient and answering "no" to the diabetes question (n = 338) were included. MEASUREMENTS AND MAIN RESULTS--A very thorough search was made in the medical files of the general practitioners in the municipality for corresponding information. Compared to the files, diabetes was verified in 163 out of the 169. The commonest cause of discrepancy was renal glycosuria. One out of the 338 registered non-diabetic persons was found to have diabetes. Diabetic patients tended to overestimate diabetes duration significantly. Insulin treatment was verified in 19/20 (95%) and treatment with oral hypoglycaemic agents in all 44 with an affirmative questionnaire answer. A negative answer on insulin and oral hypoglycaemic agents was verified in 100% and 99% respectively. CONCLUSIONS--The concordance was considerably higher than in a comparable Norwegian study performed 10 years earlier. Patient administered questionnaires may be a very reliable source of information for epidemiological purposes in a well defined chronic disease such as diabetes mellitus.     

Spatial and socio-demographic predictors of time-to-immunization in a rural area in Kenya: Is equity attainable?

We conducted a vaccine coverage survey in Kilifi District, Kenya in order to identify predictors of childhood immunization. We calculated travel time to vaccine clinics and examined its relationship to immunization coverage and timeliness among the 2169 enrolled children (median age: 12.5 months). 86% had vaccine cards available, >95% had received three doses of DTP-HepB-Hib and polio vaccines and 88% of measles. Travel time did not affect vaccination coverage or timeliness. The Kenyan EPI reaches nearly all children in Kilifi and delays in vaccination are few, suggesting that vaccines will have maximal impact on child morbidity and mortality.     

How should patients consult? A study of the differences in viewpoint between doctors and patients

BACKGROUND: Increasing pressure on limited NHS resources has led to the introduction in primary care of a skill mix which seeks to match clinical presentation to an intervention based on skills and training. There has also been increasing emphasis on the use of telephone consultations. However, outcomes on the benefits of these different approaches may be difficult to obtain and process variables such as the views of patients may be important. OBJECTIVE: The objective of the study was to answer the following questions (i) how many existing GP consultations do doctors and patients assess as being suitable for consultation with a specially trained nurse or for telephone advice from a doctor?; (ii) do doctors and patients share similar views on the suitability of individual cases?; and (iii) do these assessments differ between acute, chronic and urgent cases? METHOD: A sample of 750 patients comprising of 150 patients attending for booked consultation with each of five doctors were interviewed prior to the consultation and asked whether they would be happy to see a specially trained practice nurse or if their problem could be dealt with by a doctor on the telephone. For each case the GP gave his response. A similar study was undertaken with 150 'extras' patients who needed to be seen urgently and who could not wait for an appointment the following day. The viewpoint of the GP was compared with that of the patient. RESULTS: GPs felt that 20% of all booked cases could be seen by a nurse compared with the patients' assessment of 29%. These figures were higher for acute booked cases (30 and 34%) and for urgent extras (44 and 58%). There was a poor agreement between the viewpoints of doctor and patient especially for chronic booked cases although this agreement increased with the more acute presentations. The number of cases that could be dealt with on the telephone ranged from 5 to 9% with poor agreement between doctor and patient. CONCLUSION: This study extends the findings of a number of others which indicate that patients can be seen satisfactorily by nurses, and that both doctors and patients see scope for increasing the number of consultations dealt with by nurses. Booked patients with chronic presentations and urgent extras are more likely than their doctors to think that they could be dealt with by the nurse. This may be due to a difference in perspective between doctors and patients about the outcome they hope to achieve in the consultation. Further qualitative work is needed to explore these differences and to clarify the best approach to this expanding area.     

The reproducibility of a food frequency questionnaire among controls participating in a case‐control study on cancer

This study was designed to test the reproducibility of a food frequency questionnaire used in a population‐based case‐control study on diet and pancreatic cancer. Repeat questionnaires covering the same time period were obtained using 63 male and female population controls, 35–79 years of age. For selected food items included in the case‐control study, the attenuation of the odds ratios due to random error was estimated. Using 54 male and female population controls, 35–79 years of age, we conducted a second study to examine the agreement between original and repeat interviews when the time interval between interview and the period of interest was constant.

In the first study, the median correlation coefficient was 0.72 for foods (ranging from 0.36 and 0.59 for subgroups of vegetables to 0.96 for alcoholic beverages) and 0.77 for nutrients (ranging from 0.62 for β‐carotene to 0.85 for energy and 0.91 for ethanol). In the second study, the median correlation coefficient was 0.68 for foods (ranging from 0.28 for eggs to 0.87 for alcoholic beverages) and 0.75 for nutrients (ranging from 0.48 for β‐carotene to 0.76 for energy).

We conclude that for most items the agreement between original and repeat estimates was moderate (r> 0.50) to high (r > 0.70). Moderate agreement was found for 28 of 33 food items (85%) and for all 21 nutrient items (100%) and high agreement for 19 of 33 of food items (56%) and 15 of 21 nutrient items (71 %). In the second study, agreement was somewhat lower but closely paralleled the results of the first study. On average, random error presumably attenuated most of the observed diet‐cancer relationships only moderately; i.e., an observed odds ratio of 1.5 and a correlation coefficient of 0. 70 yield an unattenuated odds ratio of 2.1.     

Quantifying the association between Campylobacter infection and Guillain-Barré syndrome: a systematic review

Guillain-Barré Syndrome (GBS) is a neurologic disease that causes ascending paralysis and is triggered by a preceding bacterial or viral infection. Several studies have shown that patients with GBS have a recent history of infection due to Campylobacter jejuni. A literature review of published studies that reported rates of Campylobacter infection before or in conjunction with GBS was done. These reported data were used for calculating the proportion of GBS cases who tested positive for Campylobacter compared to the control population and the incidence of GBS among patients infected with Campylobacter. Results of the analysis suggest that 31% of 2,502 GBS cases included in these papers are attributable to Campylobacter infection.     

Development and relative validity of a food frequency questionnaire for the estimation of intake of retinol and β‐carotene

The aim of this study was to develop and validate a semiquantitative food frequency questionnaire to classify individuals according to their intakes of retinol and β‐carotene. Food items for the questionnaire were selected both on the basis of their contribution to total population intake of retinol and β‐carotene and on the proportion of between‐person variation explained, which was as calculated from data of two study populations in the Netherlands. Thus, 15 products containing retinol and 15 products containing β‐carotene were selected. These contributed over 90% to the total intake and explained 99% of the variation of retinol and β‐carotene, respectively. The questionnaire was validated against a dietary history in a population of 82 women (aged 30–49 years). The time elapsed between the two interviews was (on average) 25 days. Spearman rank‐order correlation coefficients comparing the questionnaire with the dietary history were 054, 0.59, and 0.64 for retinol, β‐carotene, and total vitamin A, respectively. The proportion of exact agreement in the two extreme categories of vitamin A intake, based on quintiles, was 56%. The corresponding gross misclassification (from 1 extreme category into the opposite) was 3%. These data indicate that a very short questionnaire can classify subjects into categories according to their vitamin A intake.