Impact of mediterranean diet promotion on environmental sustainability: a longitudinal analysis.

OBJECTIVE: This article aims to estimate the differences in environmental impact (greenhouse gas [GHG] emissions, land use, energy used, acidification and potential eutrophication) after one year of promoting a Mediterranean diet (MD). METHODS: Baseline and 1-year follow-up data from 5800 participants in the PREDIMED-Plus study were used. Each participant's food intake was estimated using validated semi-quantitative food frequency questionnaires, and the adherence to MD using the Dietary Score. The influence of diet on environmental impact was assessed through the EAT-Lancet Commission tables. The influence of diet on environmental impact was assessed through the EAT-Lancet Commission tables. The association between MD adherence and its environmental impact was calculated using adjusted multivariate linear regression models. RESULTS: After one year of intervention, the kcal/day consumed was significantly reduced (-125,1 kcal/day), adherence to a MD pattern was improved (+0,9) and the environmental impact due to the diet was significantly reduced (GHG: -361 g/CO2-eq; Acidification:-11,5 g SO2-eq; Eutrophication:-4,7 g PO4-eq; Energy use:-842,7 kJ; and Land use:-2,2 m2). Higher adherence to MD (high vs. low) was significantly associated with lower environmental impact both at baseline and one year follow-up. Meat products had the greatest environmental impact in all the factors analysed, both at baseline and at one-year follow-up, in spite of the reduction observed in their consumption. CONCLUSIONS: A program promoting a MD, after one year of intervention, significantly reduced the environmental impact in all the factors analysed. Meat products had the greatest environmental impact in all the dimensions analysed.

Health-related quality of life and mortality in the 'Seguimiento Universidad de Navarra' prospective cohort study.

OBJECTIVE: To study the association between health-related quality of life (HRQoL) and all-cause mortality in a healthy middle-aged Mediterranean cohort. METHODS: We included 15,390 participants -mean age 42.8 years at first HRQoL ascertainment, all university graduates-. HRQoL was assessed with the self-administered Medical Outcomes Study Short Form-36 (SF-36) twice, with a 4-year gap. We used multivariable-adjusted Cox regression models to address the relation between self-reported health and Physical or Mental Component Summary (PCS-36 or MCS-36) and mortality, and their interaction with prior comorbidities or adherence to the Mediterranean diet (MedDiet). RESULTS: Over 8.7 years of median follow-up time, 266 deaths were identified. Hazard ratio (HR) for the excellent vs. poor/fair category in self-reported health was 0.30 (95 % confidence interval (CI), 0.16-0.57) in the model with repeated measurements of HRQoL. Both the PCS-36 (HRquartile4(Q4)vs.Q1 0.57 [95%CI, 0.36-0.90], ptrend < 0.001; HRper+10points: 0.64 [95%CI, 0.54-0.75]) and the MCS-36 (HRQ4vs.Q1 0.67 [95%CI, 0.46-0.97], ptrend = 0.025; HRper+10points: 0.86 [95%CI, 0.74-0.99]) were inversely associated with mortality in the model with repeated measurements of HRQoL. Previous comorbidities or adherence to the MedDiet did not modify these associations. CONCLUSIONS: Self-reported HRQoL -assessed as self-reported health, PCS-36 and MCS-36- obtained with the Spanish version of the SF-36 were inversely associated with mortality risk, regardless of the presence of previous comorbidities or adherence to the MedDiet.

Caffeinated coffee consumption and risk of atrial fibrillation in two Spanish cohorts.

AIMS: The association between caffeinated coffee consumption and atrial fibrillation remains unclear. Recent studies suggest an inverse association only between a moderate caffeinated coffee consumption and atrial fibrillation, but others have reported no association. The aim of our study was to prospectively assess the association between caffeinated coffee consumption and atrial fibrillation in two Spanish cohorts, one of adults from a general population and another of elderly participants at high cardiovascular risk. METHODS AND RESULTS: We included 18,983 and 6479 participants from the 'Seguimiento Universidad de Navarra' (SUN) and 'Prevención con Dieta Mediterránea' (PREDIMED) cohorts, respectively. Participants were classified according to their caffeinated coffee consumption in three groups: ≤3 cups/month, 1-7 cups/week, and >1 cup/day. We identified 97 atrial fibrillation cases after a median follow-up of 10.3 years (interquartile range 6.5-13.5), in the SUN cohort and 250 cases after 4.4 years median follow-up (interquartile range 2.8-5.8) in the PREDIMED study. No significant associations were observed in the SUN cohort although a J-shaped association was suggested. A significant inverse association between the intermediate category of caffeinated coffee consumption (1-7 cups/week) and atrial fibrillation was observed in PREDIMED participants with a multivariable-adjusted hazard ratio = 0.53 (95% confidence interval 0.36-0.79) when compared with participants who did not consume caffeinated coffee or did it only occasionally. No association was found for higher levels of caffeinated coffee consumption (>1 cup per day), hazard ratio = 0.79 (95% confidence interval 0.49-1.28). In the meta-analysis of both PREDIMED and SUN studies, the hazard ratio for intermediate consumption of caffeinated coffee was 0.60 (95% confidence interval 0.44-0.82) without evidence of heterogeneity. Similar findings were found for the association between caffeine intake and atrial fibrillation risk. CONCLUSION: Intermediate levels of caffeinated coffee consumption (1-7 cups/week) were associated with a reduction in atrial fibrillation risk in two prospective Mediterranean cohorts.

Leisure-time physical activity, sedentary behavior, and risk of breast cancer: Results from the SUN ('Seguimiento Universidad De Navarra') project.

Evidence is still limited on the influence of sedentary lifestyles on breast cancer (BC) risk. Also, prospective information on the combined effects of both sedentariness and leisure-time physical activity (LTPA) is scarce. We aimed to assess the association of higher sedentary behavior and LTPA (separately and in combination) with the risk of BC in a middle-aged cohort of university graduates. The SUN Project is a follow-up study initiated in 1999 with recruitment permanently open. Baseline assessments included a validated questionnaire on LTPA and sedentary habits. Subsequently, participants completed biennial follow-up questionnaires. Multivariable adjusted Cox models were used to estimate the hazard ratios (HR) for incident BC according to LTPA, TV-watching, the joint classification of both, and a combined 8-item multidimensional active lifestyle score. We included 10,812 women, with 11.8 years of median follow-up of. Among 115,802 women-years of follow-up, we confirmed 101 incident cases of BC. Women in the highest category of LTPA (>16.5 MET-h/week) showed a significantly lower risk of BC (HR = 0.55; 95% CI: 0.34-0.90) compared to women in the lowest category (≤6 MET/h-week). Women watching >2 h/d of TV sh owed a higher risk (HR = 1.67; 95% CI:1.03-2.72) than those who watched TV <1 h/d. Women in the highest category (6-8 points) of the multidimensional combined 8-item score showed a lower BC risk (HR = 0.35; 95% CI: 0.15-0.79) than those in the lowest category (<2 points) group. There was no significant supra-multiplicative interaction between TV-watching and LTPA. Both low LTPA and TV-watching >2 h/d may substantially increase BC risk, independently of each other.

PREvention of recurrent arrhythmias with Mediterranean diet (PREDIMAR) study in patients with atrial fibrillation: Rationale, design and methods.

Background: Atrial fibrillation (AF) is the most common cardiac arrhythmia. Catheter ablation aims to restore sinus rhythm. However, relapses occur in up to 30% of patients. A Mediterranean diet (MedDiet) enriched with extra-virgin olive oil (EVOO) substantially reduced the incidence of AF in the PREDIMED trial. The PREDIMAR will test a similar intervention in secondary prevention. Methods: PREDIMAR is a multicenter, randomized, single-blind trial testing the effect of a MedDiet enriched with EVOO to reduce tachyarrhythmia relapses after AF ablation. The primary outcome is the recurrence of any sustained atrial tachyarrhythmia after ablation (excluding those occurring only during the first 3 months after ablation). The target final sample size is 720 patients (360 per group) recruited from 4 Spanish hospitals. A remote intervention, maintained for 2 years, is delivered to the active intervention group including periodic phone calls by a dietitian and free provision of EVOO. The control group will receive delayed intervention after trial completion. Routine electrocardiogram (ECG) and Holter ECG are performed, and a portable cardiac rhythm monitoring device is provided to be worn by participants during 15 months. Results: Recruitment started in March 2017. Up to July 2019, 609 patients were randomized (average inclusion rate: 5.3 patients/wk). Retention rates after 18 months are >94%. Conclusions: If our hypothesis is confirmed, the utility of the MedDiet enriched with EVOO in slowing the progression of AF will be proven, preventing recurrences and potentially reducing complications.

Mediterranean alcohol-drinking pattern, low to moderate alcohol intake and risk of atrial fibrillation in the PREDIMED study.

BACKGROUND AND AIMS: There is ongoing controversy about the effect of a low to moderate alcohol consumption on atrial fibrillation (AF). Our aim is to assess the association between adherence to a Mediterranean alcohol drinking pattern and AF incidence. METHODS AND RESULTS: A total 6527 out of the 7447 participants in the PREDIMED trial met our inclusion criteria. A validated frequency food questionnaire was used to measure alcohol consumption. Participants were classified as non-drinkers, Mediterranean alcohol drinking pattern (MADP) (10-30 g/d in men and 5-15 g/day in women, preferably red wine consumption with low spirits consumption), low-moderate drinking (<30 g/day men y and < 15 g/day women), and heavy drinking. We performed multivariable Cox regression models to estimate hazard ratios (HR) with 95% confidence intervals (95% CI) of incident AF according to alcohol drinking patterns. After a mean follow up of 4.4 years, 241 new incident AF cases were confirmed. Alcohol consumption was not associated to AF incidence among low-moderate drinkers (HR: 0.96; 95%CI: 0.67-1.37), adherents to MADP (HR: 1.15 95%CI: 0.75-1.75), or heavy drinkers (HR: 0.92; 95%CI: 0.53-1.58), compared with non-drinkers. CONCLUSIONS: In a high cardiovascular risk adult population, a Mediterranean alcohol consumption pattern (low to moderate red wine consumption) was not associated with an increased incidence of AF. CLINICAL TRIALS: URL: http://www.controlled-trials.com. Unique identifier: ISRCTN35739639.

Olive oil intake and risk of atrial fibrillation in the SUN cohort.

BACKGROUND AND AIMS: A Mediterranean-type diet enriched with extra virgin olive oil has been associated with a reduction in the incidence of atrial fibrillation (AF) in a population at high cardiovascular risk. However, no study has replicated these findings. In our study, we analyzed the association between olive oil consumption and AF in the SUN project, a cohort with young Spanish adults at low cardiovascular risk. METHODS AND RESULTS: We included all participants without prevalent AF at baseline (18,118 participants). Incident AF cases were confirmed by a cardiologist following a prespecified protocol. We used multivariable repeated-measurement Cox models adjusted for possible confounders (sex, age, BMI, and several classic cardiovascular risk factors). After a mean follow-up of 10.1 years, 94 AF incident cases were confirmed. Comparing to the lowest category of consumption (<7.9 g/d), the multivariable models showed hazard ratios (IC 95%) of 1.52 (0.93-2.48) for low-to-moderate, 1.44 (0.83-2.47) for moderate-to-high and 1.27 (0.56-2.86) for high olive oil intake. In a subgroup analysis stratified by overweight, an inverse although non-significant association was found only among overweight participants when we compared the highest vs the lowest category of consumption (p for interaction = 0.043). CONCLUSION: No association between olive oil and AF was found in this low-risk cohort, although the effect of extra-virgin olive oil on AF prevention especially among people with overweight deserves further investigation.

Coffee consumption and risk of hypertension in the SUN Project.

BACKGROUND & AIMS: Evidence on coffee consumption and its association with the incidence of hypertension is still inconsistent. The aim of this study was to examine the association of regular or decaffeinated coffee consumption with the risk of developing hypertension in a middle-aged Mediterranean cohort. METHODS: The SUN Project is a prospective open cohort with more than 22,500 Spanish university graduates. For the present study, we analyzed data from 13,374 participants initially free of hypertension (mean follow-up 9.1 years). The consumption of regular and decaffeinated coffee was obtained at baseline using a previously validated semi-quantitative food frequency questionnaire. Validated, self-reported medical diagnoses of hypertension were collected biennially. We used Cox regression models to estimate hazard ratios (HR) and 95% confidence intervals (95% CI) for incident hypertension according to baseline coffee consumption. We assessed the interaction with sex and baseline adherence to the Mediterranean diet. RESULTS: Among 121,397 person-years of follow-up, a total of 1757 participants developed hypertension. Overall, coffee consumption -either caffeinated or decaffeinated- was not significantly associated with the risk of hypertension. Only among women, higher consumption of regular coffee was associated with a 26% lower risk of hypertension (>=2 cups/d vs. never/seldom, 95% CI 9%-39%; p for interaction: 0.0236). Women with a low baseline adherence to the Mediterranean diet showed the strongest risk reduction (HR ≥ 2 cups/d vs. never/seldom 0.58, 95% CI (0.41-0.82) p for interaction = 0.0452). CONCLUSION: In the SUN project we found an inverse association between regular coffee consumption and the risk of hypertension in women, which was strongest among women with a suboptimal food pattern (low adherence to the Mediterranean diet).

Dietary inflammatory index and incidence of breast cancer in the SUN project.

BACKGROUND & AIMS: Breast cancer (BC) is the most commonly diagnosed cancer, and diet is suspected to play a role in its development. Dietary factors may mediate this process through modulation of inflammation, though findings from previous studies have not been consistent. We aimed to longitudinally assess the association between the dietary inflammatory index (DII®), a frequently used method to assess the inflammatory potential of the diet, and incident BC. METHODS: We included 10,713 middle-aged, Spanish female university graduates from the SUN cohort. DII® scores were derived from a validated 136-item food-frequency questionnaire, and it was based on scientific evidence on the relationship between diet and inflammatory biomarkers. Diagnosis of BC was reported by the participant or, if deceased, by the next of kin or identified from death certificates. Self-reports of BC were confirmed by revision of medical reports by an experienced oncologist. Cox proportional hazard models were used to estimate multivariable-adjusted hazard ratios (HR) and 95% confidence intervals (CI) for the association between quartiles of DII® and incident BC. RESULTS: After 10.3 years of median follow-up, we identified 100 confirmed and 168 probable incident BC cases. The multivariable-adjusted HR for participants in the 4th quartile to the 1st quartile was 1.44 (95% CI 0.76-2.72; p-trend: 0.339) when confirmed cases were analyzed, and 1.20 (95% CI 0.72-1.99; p-trend: 0.757) for the probable cases. We neither observed statistically significant differences in regard to menopausal status. CONCLUSIONS: The apparent increase in risk between DII® scores and BC in our cohort was not statistically significant, which could be partly explained by the small number of observed cases.

[Does Omega-3 supplementation after the age of 65 influence cognitive function? Results of a systematic review]. / ¿La ingesta o suplementación con ácidos grasos omega-3 a partir de los 65 años influye en la función cognitiva? Resultados de una revisión sistemática.

BACKGROUND: The percentage of the older population is progressively increasing as are diseases associated with aging such as cognitive decline (CD) and dementia. Observational epidemiological studies suggest that diets rich in omega 3 polyunsaturated fatty acids (w3-PUFA) might reduce the risk of CD and dementia. The main objective was to assess whether there is sufficient scientific evidence about the relationship between w3-PUFA supplementation in patients aged 65 or older and cognitive performance. METHODS: We used the Pubmed data base to search for articles related to w3-PUFA and CD or dementia. Initially we identified 582 articles, after applying the eligibility criterion we included six studies in this systematic review. RESULTS: The studies included were heterogeneous regarding population, measurement of exposure and outcome. Therefore, it was not possible to conduct a quantitative analysis. Two studies found that w3-PUFA supplementation decreased the risk of Alzheimer and improved cognitive performance. Two studies found an improvement in only one of the domains of cognitive performance (visual analogical classification and verbal fluency) and another two did not find any evidence of protection. CONCLUSIONS: We found few studies to support or refute the evidence that w3-PUFA supplementation in patients aged 65 or older improves cognitive performance or prevents dementia.

Association between a dietary carbohydrate index and cardiovascular disease in the SUN (Seguimiento Universidad de Navarra) Project.

BACKGROUND AND AIMS: Beyond the quantity of carbohydrate intake, further research is needed to know the relevance of carbohydrate quality following operational indices. No previous longitudinal study has assessed the association between an index for quality of dietary carbohydrate intake and the risk of cardiovascular disease (CVD). Here, we examined the association between a carbohydrate quality index (CQI) and the risk of CVD. METHODS AND RESULTS: We used a validated semi-quantitative 136-item food-frequency questionnaire (FFQ) in a prospective follow-up study of 17,424 middle-aged adults from Spain. The CQI was defined by four criteria: dietary fiber intake, glycemic index, whole-grain/total-grain carbohydrate ratio, and solid/total carbohydrate ratio. We observed 129 incident cases of CVD during 10.1 y of median follow-up. An inverse association for CQI was found (hazard ratio = 0.44, 95% confidence interval (CI): 0.25-0.78 for the highest versus the lowest tertile, p for trend = 0.008). Participants in the highest tertile of the whole-grain/total-grain carbohydrate ratio had 47% lower risk of CVD (95% CI: 0.33-0.85, p for trend = 0.008). Participants with higher baseline CQI and higher baseline energy from carbohydrates had the lowest risk of CVD. CONCLUSION: In this Mediterranean cohort, a better quality of dietary carbohydrates measured by the CQI, showed a significant inverse association with the incidence of CVD. Specially, a higher proportion of carbohydrates from whole grains was strongly inversely associated with CVD. "Heart-healthy" diets should be focused not only on carbohydrate quantity but also on a multidimensional assessment of the type and quality of carbohydrates.

Yogurt consumption and abdominal obesity reversion in the PREDIMED study.

BACKGROUND AND AIMS: Evidence on the association yogurt consumption and obesity is not conclusive. The aim of this study was to prospectively evaluate the association between yogurt consumption, reversion of abdominal obesity status and waist circumference change in elderly. METHODS AND RESULTS: 4545 individuals at high cardiovascular risk were prospectively followed. Total, whole-fat and low-fat yogurt consumption were assessed using food frequency questionnaires. Generalized estimating equations were used to analyze the association between yogurt consumption and waist circumference change (measured at baseline and yearly during the follow-up). Logistic regression models were used to evaluate the odds ratios (ORs) and 95% CIs of the reversion rate of abdominal obesity for each quintile of yogurt consumption compared with the lowest quintile. After multivariable adjustment, the average yearly waist circumference change in the quintiles of whole-fat yogurt consumption was: Q1: 0.00, Q2: 0.00 (-0.23 to 0.23), Q3: -0.15 (-0.42 to 0.13), Q4: 0.10 (-0.21 to 0.42), and Q5: -0.23 (-0.46 to -0.00) cm; p for trend = 0.05. The ORs for the reversion of abdominal obesity for whole-fat yogurt consumption were Q1: 1.00, Q2: 1.40 (1.04-1.90), Q3: 1.33 (0.94-1.89), Q4: 1.21 (0.83-1.77), and Q5: 1.43 (1.06-1.93); p for trend = 0.26. CONCLUSION: Total yogurt consumption was not significantly associated with reversion of abdominal obesity status and a lower waist circumference. However, consumption of whole-fat yogurt was associated with changes in waist circumference and higher probability for reversion of abdominal obesity. Therefore, it seems that whole-fat yogurt has more beneficial effects in management of abdominal obesity in elderly population at high cardiovascular risk.

Dietary inflammatory index and anthropometric measures of obesity in a population sample at high cardiovascular risk from the PREDIMED (PREvención con DIeta MEDiterránea) trial.

The dietary inflammatory index (DII) is a new tool to assess the inflammatory potential of the diet. In the present study, we aimed to determine the association between the DII and BMI, waist circumference and waist:height ratio (WHtR). We conducted a cross-sectional study of 7236 participants recruited into the PREvención con DIeta MEDiterránea trial. Information from a validated 137-item FFQ was used to calculate energy, food and nutrient intakes. A fourteen-item dietary screener was used to assess adherence to the Mediterranean diet (MeDiet). Sex-specific multivariable linear regression models were fitted to estimate differences (and 95 % CI) in BMI, waist circumference and WHtR across the quintiles of the DII. All nutrient intakes, healthy foods and adherence to the MeDiet were higher in the quintile with the lowest DII score (more anti-inflammatory values) except for intakes of animal protein, saturated fat and monounsaturated fat. Although an inverse association between the DII and total energy was apparent, the DII was associated with higher average BMI, waist circumference and WHtR after adjusting for known risk factors. The adjusted difference in the WHtR for women and men between the highest and lowest quintiles of the DII was 1·60 % (95 % CI 0·87, 2·33) and 1·04 % (95 % CI 0·35, 1·74), respectively. Pro-inflammatory scores remained associated with obesity after controlling for the effect that adherence to a MeDiet had on inflammation. In conclusion, the present study shows a direct association between the DII and indices of obesity, and supports the hypothesis that diet may have a role in the development of obesity through inflammatory modulation mechanisms.

Yogurt consumption, weight change and risk of overweight/obesity: the SUN cohort study.

BACKGROUND AND AIMS: Epidemiological studies on the association between yogurt consumption and the risk of overweight/obesity are scarce. We prospectively examined the association of yogurt consumption with overweight/obesity and average annual weight gain. METHODS AND RESULTS: Prospective cohort study of 8516 men and women (mean age 37.1, SD: 10.8 y). Participants were followed-up every two years. Participants were classified in 5 categories of yogurt consumption at baseline: 0-2, >2-<5, 5-<7, 7 and ≥ 7 servings/week. Outcomes were: 1) average yearly weight change during follow-up; and 2) incidence of overweight/obesity. Linear regression models and Cox models were used to adjust for potential confounders. After a median follow-up of 6.6 years, 1860 incident cases of overweight/obesity were identified. A high (>7 servings/week) consumption of total and whole-fat yogurt was associated with lower incidence of overweight/obesity [multivariable adjusted hazard ratios = 0.80 (95% CI: 0.68-0.94); and 0.62 (0.47-0.82) respectively] in comparison with low consumption (0-2 servings/week). This inverse association was stronger among participants with higher fruit consumption. CONCLUSION: In this Mediterranean cohort, yogurt consumption was inversely associated with the incidence of overweight/obesity, especially among participants with higher fruit consumption.

Adherence to the Mediterranean diet and quality of life in the SUN Project.

BACKGROUND/OBJECTIVES: Mediterranean diet has been related with reduced morbidity and better well-being. The aim of this study was to assess whether the adherence to the Mediterranean diet were associated with mental and physical health related to quality of life. SUBJECTS/METHODS: This analysis included 11 015 participants with 4 years of follow-up in the SUN Project (a multipurpose cohort study based on university graduates from Spain). A validated 136-item food frequency questionnaire was used to assess the adherence to the Mediterranean diet at baseline, according to a nine-point score, presented in four categories (low, low-moderate, moderate-high and high). Health-related quality of life (HRQL) was measured after 4 years of follow-up with the Spanish version of the SF-36 Health Survey. Generalized Linear Models were fitted to assess adjusted mean scores, the regression coefficients (ß) and their 95% confidence intervals (95% CIs) for the SF-36 domains according to categories of adherence to Mediterranean diet. RESULTS: Multivariate-adjusted models revealed a significant direct association between adherence to Mediterranean diet and all the physical and most mental health domains (vitality, social functioning and role emotional). Vitality (ß=0.50, 95% CI=0.32-0.68) and general health (ß=0.45, 95% CI=0.26-0.62) showed the highest coefficients. Mean values for physical functioning, role physical, bodily pain, general health and vitality domains were significantly better with increasing adherence to the Mediterranean diet. Those having improved their initial high diet scores have better scores in physical functioning, general health and vitality. CONCLUSIONS: Adherence to the Mediterranean diet seems to be a factor importantly associated with a better HRQL.

[Deficiencies in consent forms for genomic research]. / Deficiencias en las Hojas de Información de Estudios Genómicos.

INTRODUCTION: whenever biological samples are requested for genomic research consent from donors is always needed. in this process, appropriate information offered to participants is essential. the aim of this study is to assess the information included in consent forms from genomic studies. MATERIAL AND METHODS: a 51-item checklist was used to perform a content analysis of consent forms offered to sample donors. We included all consent forms used in genomic research projects approved by an Ethics Review Committee between 2004 and 2007. RESULTS: consent forms from 68 genomic studies were reviewed. 58 (85%) of those were international studies and promoted by the pharmaceutical industry. We found some important deficiencies in the consent forms on the information related to the sample's use: less than 50% mentioned aspects related to the ownership of the sample, the free donation of the sample or the place of sample storage. There have also been frequent omissions related to the genetic data such as the right to know the results of the research, the disclosure of information to family members or the length of time during which these genetic data will be stored. CONCLUSIONS: important omissions have been found in the assessed consent forms on aspects related to the use of samples and genetic data. Therefore, a substantial improvement should be undertaken in the consent forms in order to comply both with the requirements established in the Spanish biomedical law and the ethical demands.

Researchers' preferences and attitudes on ethical aspects of genomics research: a comparative study between the USA and Spain.

INTRODUCTION: The use of human samples in genomic research has increased ethical debate about informed consent (IC) requirements and the information that subjects should receive regarding the results of the research. However, there are no quantitative data regarding researchers' attitudes about these issues. METHODS: We present the results of a survey of 104 US and 100 Spanish researchers who had published genomic epidemiology studies in 61 journals during 2006. RESULTS: Researchers preferred a broader IC than the IC they had actually obtained in their published papers. US authors were more likely than their Spanish colleagues to support obtaining a broad IC, covering either any future research project or any projects related to a group of diseases (67.6% vs 43%; adjusted OR = 4.84, 95% CI, 2.32 to 10.12). A slight majority of researchers (55.8%) supported informing participants about individual genomic results only if the reliability and clinical validity of the information had been established. Men were more likely than women to believe that patients should be informed of research results even if these conditions were not met (adjusted OR = 2.89, 95% CI = 1.46 to 5.72). CONCLUSIONS: This study provides evidence of a wide range of views among scientists regarding some controversial ethical issues related to genomic research, suggesting the need for more study, debate and education. In the interim, journals might consider including the investigators' policies regarding these ethical issues in the papers they publish in the field of genomic epidemiology.

[Differences in the quality of Spanish clinical trials published in international periodicals and of the ones presented in general medicine periodicals with wide readership]. / Diferencias en la calidad de los ensayos clínicos españoles publicados en revistas internacionales y los aparecidos en revistas generales de medicina de gran difusión.

BACKGROUND: The assessment of the methodological quality of controlled clinical trials (CCTs) carried out in Spain and published in international journals and the comparison with those published in widely read general journals of medicine (N Engl J Med, Lancet, JAMA, BMJ) may help establishing their limitations and improving quality in future studies. METHODS: Search in Medline of CCTs. Studies were evaluated according to a structured questionnaire (J Clin Epidemiol 1992; 45:225-265). The odds ratio and their 95% confidence intervals were used to compare spanish studies with the remaining studies. The following variables were considered as confounders and controlled for by logistic regression analysis: number of participating centers, sample size, funding source, and the inclusion of epidemiologists in the research team. The journal's impact factor was taken into account. RESULTS: Spanish CTTs had a smaller sample size, were mostly monocentric, reported les frequently the source of funding, and exhibited a lower participation of epidemiologists. The informed consent and the approval by the ethics committee were more frequently omitted. The major methodological differences with the other studies were: lack of pre-study sample size and statistical power estimation, lack of inclusion criteria, poor explanation of patients' flow in the selection process, lack of explanation for unmasked procedures, poor description of methods to assess intervention compliance, under-reporting confidence intervals, and less frequent use of the intention-to-treat principle. The quality score of spanish studies was lower (9.4 +/- 1.7 vs 10.7 +/- 1.5; p < 0.001). These limitations improved with higher journal's impact factor, the quality score was 8.5 in journals with an impact factor < 1.5, and 10.6 in those with an impact factor > 4.5. This last figure is almost identical to the average of CCTs published in general journals of medicine. CONCLUSIONS: Most spanish studies achieved a good quality score. Nevertheless, there are still issues which can be overcome easily. If this goal is achieved, the results will obtain a higher repercussion, as a better quality is observed in those published in journals with the highest impact factor.

Participation of epidemiologists and/or biostatisticians and methodological quality of published controlled clinical trials.

STUDY OBJECTIVE: This study assessed several methodological aspects related to the quality of published controlled clinical trials (CCTs) in relation to the participation of an epidemiologist/biostatistician (E/B). DESIGN: Handsearch of CCTs published in four medical leading journals for 1993-1995. METHODS: Quality variables, abstracted from a review, were related to authors' specialties. Five hundred and ninety four CCTs were identified via a hand search. The department/unit membership was used to attribute authors' specialties. Of 594 CCTs identified, in 127 the authors' specialties could not be known, leaving 467 trials for analysis. RESULTS: E/B participation occurred in 178 trials (38.1%). This participation was more frequent in multicentric, bigger, and in those trials describing any funding agency. These factors were controlled for in the analysis. E/B participation was positively associated with pre-study sample size estimation (OR = 1.5, 95% confidence intervals (CI) 1.0, 2.3), with reporting the dates for starting/ending the study (OR = 2.1, 95% CI 1.4, 3.3), with using an objectively assessed outcome (OR = 2.4, 95% CI 1.2, 4.6) and with the intention to treat principle (OR = 2.0, 95% CI 1.3, 3.0). The overall quality score was higher in trials where E/B participated. CONCLUSIONS: The results suggest that E/B improve the quality (at least of reports) of clinical trials. Given that quality of research is frequently used to evaluate potential sources of heterogeneity between trials, these results are relevant for meta-analysis.