Paula Carrasco

Relative validity of a semi-quantitative food-frequency questionnaire in an elderly Mediterranean population of Spain

The aim of the present study was to assess reproducibility and relative validity of a self-administered FFQ used in the PREDIMED Study, a clinical trial for primary prevention of CVD by Mediterranean diet in a population at high cardiovascular risk. The FFQ was administered twice (FFQ1 and FFQ2) to explore reproducibility at 1 year. Four 3 d dietary records (DR) were used as reference to explore validity; participants therefore recorded their food intake over 12 d in the course of 1 year. The degree of misclassification in the FFQ was also evaluated by a contingency table of quintiles comparing the information from the FFQ2 and the DR. A total of 158 men and women (aged 55-80 years) were asked not to modify their dietary habits during the study period. Reproducibility for food groups, energy and nutrient intake, explored by the Pearson correlation coefficient (r) ranged 0.50-0.82, and the intraclass correlation coefficient (ICC) ranged from 0.63 to 0.90. The FFQ2 tended to report higher energy and nutrient intake than the DR. The validity indices of the FFQ in relation to the DR for food groups and energy and nutrient intake ranged (r) from 0.24 to 0.72, while the range of the ICC was between 0.40 and 0.84. With regard to food groups, 68-83 % of individuals were in the same or adjacent quintile in both methods, a figure which decreased to 55-75 % for energy and nutrient intake. We concluded that FFQ measurements had good reproducibility and a relative validity similar to those of FFQ used in other prospective studies.

Mediterranean Diet Reduces the Adverse Effect of the TCF7L2-rs7903146 Polymorphism on Cardiovascular Risk Factors and Stroke Incidence A randomized controlled trial in a high-cardiovascular-risk population

OBJECTIVE Transcription factor 7-like 2 (TCF7L2) polymorphisms are strongly associated with type 2 diabetes, but controversially with plasma lipids and cardiovascular disease. Interactions of the Mediterranean diet (MedDiet) on these associations are unknown. We investigated whether the TCF7L2-rs7903146 (C>T) polymorphism associations with type 2 diabetes, glucose, lipids, and cardiovascular disease incidence were modulated by MedDiet. RESEARCH DESIGN AND METHODS A randomized trial (two MedDiet intervention groups and a control group) with 7,018 participants in the PREvención con DIetaMEDiterránea study was undertaken and major cardiovascular events assessed. Data were analyzed at baseline and after a median follow-up of 4.8 years. Multivariable-adjusted Cox regression was used to estimate hazard ratios (HRs) for cardiovascular events. RESULTS The TCF7L2-rs7903146 polymorphism was associated with type 2 diabetes (odds ratio 1.87 [95% CI 1.62–2.17] for TT compared with CC). MedDiet interacted significantly with rs7903146 on fasting glucose at baseline (P interaction = 0.004). When adherence to the MedDiet was low, TT had higher fasting glucose concentrations (132.3 ± 3.5 mg/dL) than CC+CT (127.3 ± 3.2 mg/dL) individuals (P = 0.001). Nevertheless, when adherence was high, this increase was not observed (P = 0.605). This modulation was also detected for total cholesterol, LDL cholesterol, and triglycerides (P interaction < 0.05 for all). Likewise, in the randomized trial, TT subjects had a higher stroke incidence in the control group (adjusted HR 2.91 [95% CI 1.36–6.19]; P = 0.006 compared with CC), whereas dietary intervention with MedDiet reduced stroke incidence in TT homozygotes (adjusted HR 0.96 [95% CI 0.49–1.87]; P = 0.892 for TT compared with CC). CONCLUSIONS Our novel results suggest that MedDiet may not only reduce increased fasting glucose and lipids in TT individuals, but also stroke incidence.

Polymorphisms Cyclooxygenase-2 -765G>C and Interleukin-6 -174G>C Are Associated with Serum Inflammation Markers in a High Cardiovascular Risk Population and Do Not Modify the Response to a Mediterranean Diet Supplemented with Virgin Olive Oil or Nuts

Inflammation is involved in cardiovascular diseases. Some studies have found that the Mediterranean diet (MD) can reduce serum concentrations of inflammation markers. However, none of these studies have analyzed the influence of genetic variability in such a response. Our objective was to study the effect of the -765G>C polymorphism in the cyclooxygenase-2 (COX-2) gene and the -174G>C polymorphism in the interleukin-6 (IL-6) gene on serum concentrations of IL-6, C-reactive protein, intercellular adhesion molecule 1 (ICAM-1) and vascular cell adhesion molecule-1 as well as their influence on the response to a nutritional intervention with MD. An intervention study in a high cardiovascular risk Mediterranean population (314 men and 407 women) was undertaken. Participants were randomly assigned to consume a low-fat control diet or a MD supplemented with virgin olive oil or nuts. Measures were obtained at baseline and after a 3-mo intervention period. At baseline, the COX-2 -765G>C polymorphism was associated with lower serum IL-6 (5.85 +/- 4.82 in GG vs. 4.74 +/- 4.14 ng/L in C-allele carriers; P = 0.002) and ICAM-1 (265.8 +/- 114.8 in GG vs. 243.0 +/- 107.1 microg/L in C-carriers; P = 0.018) concentrations. These differences remained significant after multivariate adjustment. The IL-6 -174G>C polymorphism was associated with higher (CC vs. G-carriers) serum ICAM-1 concentrations in both men and women and with higher serum IL-6 concentrations in men. Following the dietary intervention, no significant gene x diet interactions were found. In conclusion, although COX-2 -765G>C and IL-6 -174G>C polymorphisms were associated with inflammation, consuming a MD (either supplemented with virgin olive oil or nuts) reduced the concentration of inflammation markers regardless of these polymorphisms.

Association of the LCT-13910C>T polymorphism with obesity and its modulation by dairy products in a Mediterranean population

The −13910C>T polymorphism (rs4988235) upstream from the lactase (LCT) gene, strongly associated with lactase persistence (LP) in Europeans, is emerging as a new candidate for obesity. We aimed to analyze the association of this polymorphism with obesity‐related variables and its modulation by dairy product intake in an elderly population. We studied 940 high‐cardiovascular risk Spanish subjects (aged 67 ± 7 years). Dairy product consumption was assessed by a validated questionnaire. Anthropometric variables were directly measured, and metabolic syndrome‐related variables were obtained. Prevalence of genotypes was: 38.0% CC (lactase nonpersistent (LNP)), 45.7% CT, and 16.3% TT. The CC genotype was not associated with lower milk or dairy product consumption in the whole population. Only in women was dairy intake significantly lower in CC subjects. The most important association was obtained with anthropometric measurements. CC individuals had lower weight (P = 0.032), lower BMI (29.7 ± 4.2 vs. 30.6 ± 4.2 kg/m2; P = 0.003) and lower waist circumference (101.1 ± 11.8 vs. 103.5 ± 11.5 cm; P = 0.005) than T‐allele carriers. Obesity risk was also significantly higher in T‐allele carriers than in CC individuals (odds ratio (OR): 1.38; 95% confidence interval (CI): 1.05–1.81; P = 0.01), and remained significant even after adjustment for sex, age, diabetes, physical activity, and energy intake. However, in subgroup analysis, these associations were found to be significant only among those consuming moderate or high lactose intakes (>8 g/day). No significant associations with lipids, glucose, or blood pressure were obtained after adjustment for BMI. In conclusion, despite not finding marked differences in dairy product consumption, this polymorphism was strongly associated with BMI and obesity and modulated by lactose intake in this Mediterranean population.

Statistical and biological gene-lifestyle interactions of MC4R and FTO with diet and physical activity on obesity: new effects on alcohol consumption

Background Fat mass and obesity (FTO) and melanocortin-4 receptor (MC4R) and are relevant genes associated with obesity. This could be through food intake, but results are contradictory. Modulation by diet or other lifestyle factors is also not well understood. Objective To investigate whether MC4R and FTO associations with body-weight are modulated by diet and physical activity (PA), and to study their association with alcohol and food intake. Methods Adherence to Mediterranean diet (AdMedDiet) and physical activity (PA) were assessed by validated questionnaires in 7,052 high cardiovascular risk subjects. MC4R rs17782313 and FTO rs9939609 were determined. Independent and joint associations (aggregate genetic score) as well as statistical and biological gene-lifestyle interactions were analyzed. Results FTO rs9939609 was associated with higher body mass index (BMI), waist circumference (WC) and obesity (P<0.05 for all). A similar, but not significant trend was found for MC4R rs17782313. Their additive effects (aggregate score) were significant and we observed a 7% per-allele increase of being obese (OR = 1.07; 95%CI 1.01–1.13). We found relevant statistical interactions (P<0.05) with PA. So, in active individuals, the associations with higher BMI, WC or obesity were not detected. A biological (non-statistical) interaction between AdMedDiet and rs9939609 and the aggregate score was found. Greater AdMedDiet in individuals carrying 4 or 3-risk alleles counterbalanced their genetic predisposition, exhibiting similar BMI (P = 0.502) than individuals with no risk alleles and lower AdMedDiet. They also had lower BMI (P = 0.021) than their counterparts with low AdMedDiet. We did not find any consistent association with energy or macronutrients, but found a novel association between these polymorphisms and lower alcohol consumption in variant-allele carriers (B+/−SE: −0.57+/−0.16 g/d per-score-allele; P = 0.001). Conclusion Statistical and biological interactions with PA and diet modulate the effects of FTO and MC4R polymorphisms on obesity. The novel association with alcohol consumption seems independent of their effects on BMI.

Education modulates the association of the FTO rs9939609 polymorphism with body mass index and obesity risk in the Mediterranean population

OBJECTIVE To define whether the rs9939609 FTO (fat mass and obesity associated) single nucleotide polymorphism (SNP) is associated with anthropometric measurements and its modulation by educational level in a Mediterranean population. METHODS We studied 3 independent adult samples: a random sample (n = 1580) from the general population (GP), obese hospital patients (OHP) (n = 203) and elderly subjects (n = 1027) with high cardiovascular risk (HCR). Weight and height were directly measured. Education and physical activity (PA) were measured using questionnaires. RESULTS The rs9939609 presented heterogeneous associations with BMI. In the GP, the minor A-allele was significantly associated with greater BMI, following a co-dominant pattern (P = 0.009), whereas in the OHP this association was recessive (P = 0.004). Conversely, we did not find a significant association with BMI in the HCR group (P < 0.596). In the GP we found a significant interaction between the FTO SNP and education (P = 0.048). In the stratified analysis, no association of the FTO SNP with greater BMI in university subjects was detected (P = 0.786), whereas the association was observed in non-university subjects (P = 0.001). The FTO × education interaction (P = 0.020) was also observed in determining obesity risk in the GP. A-allele carriers had a greater risk of being obese only if they had no university education (OR: 1.56; 95%CI: 1.09-2.23 for TA and OR: 2.01; 95%CI: 1.27-3.26 for AA subjects). The interaction of the FTO with education remained significant even after adjustment for PA. CONCLUSIONS The association of the FTO SNP with greater BMI and obesity risk in the GP was strongly modulated by education.

Impact of cardiovascular risk factors on oxidative stress and DNA damage in a high risk Mediterranean population

Abstract The impact of classic cardiovascular risk factors on oxidative stress status in a high-risk cardiovascular Mediterranean population of 527 subjects was estimated. Oxidative stress markers (malondialdehyde, 8-oxo-7′8′-dihydro-2′-deoxyguanosine, oxidized/reduced glutathione ratio) together with the activity of antioxidant enzyme triad (superoxide dismutase, catalase, glutathione peroxidase) were analysed in circulating mononuclear blood cells. Malondialdehyde, oxidized glutathione and the ratio of oxidized to reduced glutathione were significantly higher while catalase and glutathione peroxidase activities were significantly lower in high cardiovascular risk participants than in controls. Statistically significant differences were obtained after additional multivariate control for sex, age, obesity, diabetes, lipids and medications. Among the main cardiovascular risk factors, hypertension was the strongest determinant of oxidative stress in high risk subjects studied at a primary prevention stage.

Hyperhomocysteinemia and the methylene tetrahydrofolate reductase C677T mutation in splanchnic vein thrombosis.

Introduction: The role that hyperhomocysteinemia (HH) and the C677T mutation in 5,10‐methylenetetrahydrofolate reductase (MTHFR) play in splanchnic vein thrombosis (SVT) remains unclear due to this unusual thrombotic location. Objective: To analyse the possible association of HH with the C677T mutation in the MTHFR gene in SVT. Material and methods: We determined homocysteine levels and the C677T MTHFR mutation, along with classical cardiovascular risk factors, in 48 patients with SVT (18 Budd‐Chiari syndrome, 11 mesenteric vein thrombosis, 19 portal vein thrombosis) and 84 controls. Results: In the univariate analysis, patients with SVT showed statistically higher homocysteine levels (P = 0.044). After adjusting for total cholesterol, differences disappeared (P = 0.256). However, no differences in homocysteine levels were observed when comparing the three SVT types (P = 0.199), even after adjusting for age and total cholesterol (P = 0.095). In addition, the prevalence of the TT genotype was no different when controls were compared with patients with SVT (P = 0.253) or with SVT subtypes (P = 0.885). No association was found between HH (>15 μm) and the TT genotype in cases (P = 0.404), controls (P = 0.178), or in the different SVT subtypes (P = 0.495). Conclusions: Our results suggest that HH and the homozygous genotype in the MTHFR C677T mutation do not seem to play a role in SVT development.

Modulación de la expresión fenotípica del paciente con cistinuria: influencia de la intervención terapéutica y de la dieta

OBJETIVOS El fenotipo final del paciente con cistinuria depende, por una parte, de la ausencia o defecto molecular mas o menos grave en el transporte de cistina y aminoacidos dibasicos; y por otra parte tambien de factores ambientales. El objetivo del presente estudio es conocer el efecto de la modulacion de diversos factores ambientales (pH urinario, ingesta de liquido, tratamiento farmacologico y en especial la dieta) sobre el fenotipo final del paciente con cistinuria. METODOS Se estudiaron 45 sujetos diagnosticados como pacientes con cistinuria (25 hombres y 20 mujeres), 42 individuos pertenecientes al arbol genealogico de estos pacientes con cistinuria (15 hombres y 27 mujeres) y 90 controles. Se obtuvieron datos antropometricos, clinicos (antecedentes personales y familiares de infecciones urinarias, colicos, expulsion de calculos y problemas renales), bioquimicos (analisis microscopico de orina y cuantificacion de aminoacidos en orina) y estilo de vida (dieta y tratamiento recibido). El estudio estadistico incluyo, ademas de pruebas de comparacion de frecuencias y de medias, regresion logistica y analisis multivariante. RESULTADOS De los 45 pacientes con cistinuria, solo el 20% presentaban cristales de cistina en orina; el resto de manifestaciones fenotipicas de la enfermedad, se encontraron con la misma prevalencia que en el grupo de familiares y el grupo control. El 50% de los pacientes no estaban siguiendo ninguna pauta terapeutica, y de estos, solo en el 50% era efectivo. En pacientes con cistinuria, la presencia de cristales de cistina se asocio a una dieta rica en carnes y baja en productos lacteos (p<0,05). El consumo de carnes tambien tendia a asociarse a mayor riesgo de presentar infecciones urinarias, mientras que la expulsion de piedras mostro una tendencia negativa con una dieta rica en fitatos. El consumo elevado de naranjas y mandarinas fue la variable de la dieta que mas se asocio con las concentraciones de aminoacidos en orina, fundamentalmente con menores niveles de lisina y arginina (p<0,05). CONCLUSIONES Diversos componentes de la dieta, ademas del tratamiento estandar, modulan las manifestaciones fenotipicas de la enfermedad.

Variaciones en el gen SLC7A9: impacto de trece mutaciones frecuentes en la etiología de la cistinuria en población mediterránea española

Fundamento y objetivo: Investigar la presencia de mutaciones en el gen SLC7A9, descritas como mas prevalentes en otras poblaciones, en familias con cistinuria en poblacion mediterranea espanola y su asociacion con manifestaciones clinicas de la enfermedad. Pacientes y metodo: Se estudio a 20 familias con cistinuria (6 tipo I, 12 tipo no I y 2 de tipo desconocido), incluidos 48 pacientes con cistinuria y 44 familiares. Se aislo el ADN y se realizo el analisis molecular de 13 mutaciones en el gen SLC7A9 (P52L, N58_G79del22, G63R, G105R, T123M, V170M, A182T, V188M, c.614dupA, G259R, L283F, A316V y R333W). Se estudio la asociacion de estas mutaciones con las concentraciones de aminoacidos en orina, formacion de calculos, infecciones urinarias, colicos y otras manifestaciones clinicas. Resultados: De las 13 mutaciones investigadas, la mas prevalente fue la c.614dupA, que se encontro en heterocigosis en 13 pacientes con cistinuria (17,1%) y en 2 familiares, todos ellos pertenecientes a 4 familias clasificadas como tipo no I. Las mutaciones G105R (9,2%), T123M (3,9%) y N58_G79del22 (2,6%) se detectaron solo en pacientes con cistinuria tipo no I, mientras que se encontro un alelo portador de la variante R333W en un paciente de una familia en que el tipo desconocido y un alelo portador de G105R en un familiar tipo no I. Conclusiones: Aunque no se ha realizado el cribado completo del gen SLC7A9, los resultados obtenidos apuntan a que las variaciones en el gen SLC7A9 tienen un mayor impacto en la etiologia de la cistinuria en esta poblacion que las variaciones en el gen SLC3A1, previamente investigado. Ademas, la amplia variacion de las manifestaciones fenotipicas dentro de familias que comparten las mismas mutaciones resalta la importancia de la investigacion de otros factores geneticos y/o ambientales.