Charalambos Gnardellis

Diet and overall survival in elderly people

Abstract Objective: To assess the influence of a specific dietary pattern on overall survival. Design: Cohort study. Setting: Three rural Greek villages, the data from which were collected as part of an international cross cultural study of food habits in later life. Subjects: 182 elderly residents of the three villages. Main outcome measure: Overall mortality. Results: Diet was assessed with a validated extensive semiquantitative questionnaire on food intake. A one unit increase in diet score, devised a priori on the basis of eight component characteristics of the traditional common diet in the Mediterranean region, was associated with a significant 17% reduction in overall mortality (95% confidence interval 1% to 31%). Conclusion: A diet meeting currently understood health criteria does predict survival among people.

Perceived Stress Scale: Reliability and Validity Study in Greece

Objective: To translate the Perceived Stress Scale (versions PSS-4, −10 and −14) and to assess its psychometric properties in a sample of general Greek population. Methods: 941 individuals completed anonymously questionnaires comprising of PSS, the Depression Anxiety and Stress scale (DASS-21 version), and a list of stress-related symptoms. Psychometric properties of PSS were investigated by confirmatory factor analysis (construct validity), Cronbach’s alpha (reliability), and by investigating relations with the DASS-21 scores and the number of symptoms, across individuals’ characteristics. The two-factor structure of PSS-10 and PSS-14 was confirmed in our analysis. We found satisfactory Cronbach’s alpha values (0.82 for the full scale) for PSS-14 and PSS-10 and marginal satisfactory values for PSS-4 (0.69). PSS score exhibited high correlation coefficients with DASS-21 subscales scores, meaning stress (r = 0.64), depression (r = 0.61), and anxiety (r = 0.54). Women reported significantly more stress compared to men and divorced or widows compared to married or singled only. A strong significant (p < 0.001) positive correlation between the stress score and the number of self-reported symptoms was also noted. Conclusions: The Greek versions of the PSS-14 and PSS-10 exhibited satisfactory psychometric properties and their use for research and health care practice is warranted.

Are the advantages of the Mediterranean diet transferable to other populations? A cohort study in Melbourne, Australia

A prospective cohort study, involving 141 Anglo-Celts and 189 Greek-Australians of both sexes aged 70 years or more, was undertaken in Melbourne, Australia. The objective was to evaluate whether adherence to the principles of the Mediterranean diet affects survival of elderly people in developed non-Mediterranean countries. Diet was assessed using an extensive validated questionnaire on food intake. A one unit increase in a diet score, devised a priori on the basis of eight key features of the traditional common diet in the Mediterranean region, was associated with a 17% reduction in overall mortality (two-tailed P value 0.07). Mortality reduction with increasing diet score was at least as evident among Anglo-Celts as among Greek-Australians. We conclude that a diet that adheres to the principles of the traditional Mediterranean diet is associated with longer survival among Australians of either Greek or Anglo-Celtic origin.

Microvascular Reactivity and Inflammatory Cytokines in Painful and Painless Peripheral Diabetic Neuropathy

OBJECTIVE We investigated the association between inflammation, microvascular reactivity, and the development of peripheral diabetic neuropathy. RESEARCH DESIGN AND METHODS We studied three groups: 55 healthy control subjects, 80 nonneuropathic patients, and 77 neuropathic diabetic patients. We also subdivided the neuropathic patients into a subgroup of 31 subjects with painless neuropathy and 46 with painful neuropathy. We measured the foot skin endothelium-dependent and -independent vasodilation, the nerve axon reflex-related vasodilation (NARV), and inflammatory cytokines and biochemical markers of endothelial function. RESULTS The endothelium-dependent and -independent vasodilation and NARV were lower in the neuropathic group (P < 0.05). NARV was further reduced in the subgroup of painless neuropathy when compared to painful neuropathy (P < 0.05). Compared to the other two groups, the neuropathic group also had higher serum levels of PDGF AA/BB (P < 0.05), RANTES (P < 0.01), leptin (P < 0.0001), osteoprotegerin (P < 0.01), G-CSF (P < 0.05), sE-Selectin (P < 0.01), sICAM (P < 0.0001), sVCAM (P < 0.001), CRP (P < 0.0001), TNFalpha (P < 0.05), and fibrinogen (P < 0.05). Patients with painful neuropathy had higher sICAM-1 (P < 0.05) and CRP levels (P < 0.01) when compared to painless neuropathy. No major changes in the above results were observed in 78 diabetic patients who were seen for a second visit 21 months after the first visit. CONCLUSIONS Peripheral diabetic neuropathy is associated with increased biochemical markers of inflammation and endothelial dysfunction. Painful neuropathy is associated with further increase in inflammation and markers of endothelial dysfunction and preservation of the nerve axon reflex.

REPRODUCIBILITY AND VALIDITY OF AN EXTENSIVE SEMIQUANTITATIVE FOOD FREQUENCY QUESTIONNAIRE AMONG GREEK SCHOOL TEACHERS

We evaluated the reproducibility and validity of a 190-item semiquantitative food frequency questionnaire (FFQ) to be used in a large prospective study in the Athens area of Greece. Eighty persons, 42 men and 38 women, ages 25-67 years, completed a self-administered FFQ, followed by monthly 24-hour diet recalls and then a second FFQ 1 year after the first. Correlation coefficients measuring the reproducibility and validity of the FFQ indicate that the questionnaire is reproducible and provides a reasonably reliable measure of intake for many nutrients over a period of 1 year.

Mechanisms Involved in the Development and Healing of Diabetic Foot Ulceration

We examined the role of vascular function and inflammation in the development and failure to heal diabetic foot ulcers (DFUs). We followed 104 diabetic patients for a period of 18.4 ± 10.8 months. At the beginning of the study, we evaluated vascular reactivity and serum inflammatory cytokines and growth factors. DFUs developed in 30 (29%) patients. DFU patients had more severe neuropathy, higher white blood cell count, and lower endothelium-dependent and -independent vasodilation in the macrocirculation. Complete ulcer healing was achieved in 16 (53%) patients, whereas 13 (47%) patients did not heal. There were no differences in the above parameters between the two groups, but patients whose ulcers failed to heal had higher tumor necrosis factor-α, monocyte chemoattractant protein-1, matrix metallopeptidase 9 (MMP-9), and fibroblast growth factor 2 serum levels when compared with those who healed. Skin biopsy analysis showed that compared with control subjects, diabetic patients had increased immune cell infiltration, expression of MMP-9, and protein tyrosine phosphatase-1B (PTP1B), which negatively regulates the signaling of insulin, leptin, and growth factors. We conclude that increased inflammation, expression of MMP-9, PTP1B, and aberrant growth factor levels are the main factors associated with failure to heal DFUs. Targeting these factors may prove helpful in the management of DFUs.

Lipid, protein and carbohydrate intake in relation to body mass index

Objective: To examine whether the same amount of energy intake has different consequences on body mass index (BMI), depending on the source of energy from specific macronutrients.Design: Cross-sectional study, in the context of the European Prospective Investigation into Cancer and nutrition (EPIC).Setting: Communities all over Greece.Subjects: A total of 27 862 apparently healthy volunteers, men and women, ages 25–82 y.Interventions: None.Methods: Dietary information was collected through an interviewer-administered semi-quantitative food frequency questionnaire. In the context of a cross-sectional analysis, we calculated changes of BMI per increments of energy intake from protein, carbohydrates, saturated, polyunsaturated and monounsaturated lipids and ethanol, controlling for mutual confounding and other confounders, among all participants, and after exclusion of under-reporters and/or those on a diet.Results: Protein intake was positively associated with BMI. The association was evident when nutrients were not mutually adjusted for and increased after mutual adjustment among nutrients (β=0.80 kg/m2 per 418.4 kJ or 100 kcal increment, 95% confidence interval 0.55–1.06 for men, and β=1.59, 95% CI 1.30–1.88 for women), as well as after exclusion of under-reporters and/or those on a diet. The effects of other macronutrients were less substantial or consistent.Conclusions: There is evidence indicating that protein intake is conducive to obesity. Moreover, our data suggest that neither saturated or monounsaturated lipids nor carbohydrates are likely to play a major role in increasing BMI over and beyond that indicated by their energy content.Sponsorship: EPIC-Greece is supported by the Europe Against Cancer Program of the European Commission and the Greek Ministry of Health.

Diet and survival of elderly Greeks : a link to the past

In 1988 and 1989, we investigated in three Greek villages the dietary patterns of 182 men and women aged > 70 y by using a validated semiquantitative food-frequency questionnaire and compared these dietary patterns with the traditional Greek diet as ascertained in the late 1950s by Keys and his colleagues. As in the traditional diet, olive oil dominated fat intake, total fat exceeded 35% of total energy intake, average daily consumption of fruits and vegetables exceeded 500 g, and average ethanol intake for men corresponded to two to three glasses of wine per day. In contrast, consumption of meat and meat products has substantially increased and intake of bread and other cereals has apparently declined. We observed no differences between the two periods with respect to consumption of legumes, eggs and egg products, and sugar confectionery. We have also attempted to assess whether a gradient of adherence to the traditional Greek diet can be identified in the diets of the study subjects, and whether it can subsequently predict total mortality. During a follow-up period of approximately 5 y, 53 deaths were observed. The risk of death was apparently higher among the minority of study subjects whose diet deviated substantially from the traditional Greek pattern, compared with the majority whose diet adhered closely to the traditional pattern.

Body mass index in relation to energy intake and expenditure among adults in Greece.

The empirical evidence concerning the quantitative relations between energy intake and expenditure on the one hand and body mass index (BMI) on the other is inconclusive. We have used a large database of 14,281 individuals, for whom habitual dietary intake and expenditure have been ascertained with adequate methodology, to examine the mutually adjusted associations of these variables with BMI. Study subjects were adult participants in the Greek component of the European Prospective Investigation into Cancer and Nutrition (EPIC) study. After adjustment for age and gender and exclusion of dieting individuals and energy underreporters, an increment of about 500 kcal intake was found to correspond to an increment of about 0.33 kg/m2 of BMI, whereas an increment of about 5 MET-hours of energy expenditure was associated with a decrease of about 0.18 kg/m2 of BMI, where MET is the ratio of the metabolic rate associated with a given activity to the resting metabolic rate. Our results indicate that increasing physical activity is about half as effective as decreasing energy intake in reducing BMI.

Effects of diabetes and obesity on vascular reactivity, inflammatory cytokines, and growth factors.

We examined the influences of obesity and diabetes on endothelium‐dependent and ‐independent vasodilation, inflammatory cytokines, and growth factors. We included 258 subjects, age 21–80 years in four groups matched for age and gender: 40 healthy nonobese (BMI <30 kg·m−2) nondiabetic subjects, 76 nonobese diabetic patients, 37 obese (BMI >30) nondiabetic subjects, and 105 obese (BMI >30) diabetic patients. The flow‐mediated dilation (FMD, endothelium‐dependent) and nitroglycerin‐induced dilation (NID, endothelium‐independent) in the brachial artery, the vascular reactivity at the forearm skin and serum growth factors and inflammatory cytokines were measured. FMD was reduced in the nonobese diabetic patients, obese nondiabetic controls, and obese diabetic patients (P < 0.0001). NID was different among all four groups, being highest in the obese nondiabetic subjects and lowest in the obese diabetic patients (P < 0.0001). The resting skin forearm blood flow was reduced in the obese nondiabetic subjects (P < 0.01). Vascular endothelial growth factor (VEGF) was higher in the obese nondiabetic subjects (P < 0.05), tumor necrosis factor–α was higher in the obese diabetic patients (P < 0.0001) and C‐reactive protein was higher in both the obese nondiabetic and diabetic subjects (P < 0.0001). Soluble intercellular adhesion molecule‐1 was elevated in the two diabetic groups and the obese nondiabetic subjects (P < 0.05). We conclude that diabetes and obesity affect equally the endothelial cell function but the smooth muscle cell function is affected only by diabetes. In addition, the above findings may be related to differences that were observed in the growth factors and inflammatory cytokines.