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Biomedical subjects

Christos Pitsavos

Publications and source records attributed to Christos Pitsavos.

At least 73 records · Page 4Linked to original sources

Smoking and caffeine have a synergistic detrimental effect on aortic stiffness and wave reflections.

OBJECTIVES: We investigated the acute and chronic combined effect of cigarette smoking and caffeine intake on aortic stiffness and wave reflections. BACKGROUND: We have shown that smoking and caffeine separately increase arterial stiffness. Aortic stiffness and wave reflections are important determinants of the efficient performance of the cardiovascular system and prognosticators of cardiovascular risk. METHODS: The acute effects of smoking (one cigarette), caffeine (200 mg, equivalent to 2 cups of coffee), and smoking plus caffeine were studied in 24 healthy subjects according to a randomized, placebo- and sham procedure-controlled crossover design. The chronic effect of smoking and caffeine was studied in a population study that enrolled 160 healthy subjects. RESULTS: Acute study: there was a significant interaction between caffeine and smoking with regard to pulse-wave velocity (p < 0.01) and augmentation index (p < 0.05). When smoking followed caffeine intake, pulse-wave velocity and augmentation index increased further by 0.52 m/s and 13.4%, respectively, reaching a total of 0.85 m/s and 17.4%, 0.17 m/s and 9.2% in excess of the mere sum of caffeine effect (0.33 m/s and 4%) alone and smoking effect alone (0.35 m/s and 4.2%). Population study: there was a significant interaction of chronic coffee consumption and smoking regarding pulse-wave velocity (p < 0.05) and augmentation index (p = 0.001). CONCLUSIONS: The present study shows, for the first time, that when smoking and caffeine intake are combined, they interact and exert a synergistic, unfavorable effect on aortic stiffness and wave reflections on both an acute and chronic basis.

Adult↗

The J-shape association of ethanol intake with total homocysteine concentrations: the ATTICA study.

BACKGROUND: Epidemiological studies suggest a non-monotonic effect of alcohol consumption on cardiovascular risk, while there is strong evidence concerning the involvement of homocysteine levels on thrombosis. The aim of this work was to evaluate the association between usual ethanol consumption and homocysteine levels, in cardiovascular disease free adults. METHODS: From May 2001 to December 2002 we randomly enrolled 1514 adult men and 1528 women, without any evidence of cardiovascular disease, stratified by age - gender (census 2001), from the greater area of Athens, Greece. Among the variables ascertained we measured the daily ethanol consumption and plasma homocysteine concentrations. RESULTS: Data analysis revealed a J-shape association between ethanol intake (none, <12 gr, 12 - 24 gr, 25 - 48 gr, >48 gr per day) and total homocysteine levels (mean +/- standard deviation) among males (13 +/- 3 vs. 11 +/- 3 vs. 14 +/- 4 vs. 18 +/- 5 vs. 19 +/- 3 mumol/L, respectively, p < 0.01) and females (10 +/- 4 vs. 9 +/- 3 vs. 11 +/- 3 vs. 15 +/- 4 vs. 17 +/- 3 mumol/L, respectively, p < 0.01), after controlling for several potential confounders. The lowest homocysteine concentrations were observed with ethanol intake of < 12 gr/day (Bonferroni alpha* < 0.05). No differences were observed when we stratified our analysis by type of alcoholic beverage consumed. CONCLUSION: We observed a J-shape relationship between homocysteine concentrations and the amount of ethanol usually consumed.

Journal Article↗

Increased plasma homocysteine concentrations in healthy people with hostile behavior: the ATTICA study.

BACKGROUND: One of the psychological factors showing significant association with the development of coronary heart disease is hostility. However, the pathway by which hostility may affect coronary risk is not fully understood. Thus we evaluated the association between hostility and inflammation (thrombotic marker) in a population-based sample of males and females with no clinical evidence of cardiovascular disease. MATERIAL/METHODS: The ATTICA study is a health and nutrition survey carried out in the province of Attica, Greece, during 2001-2002. 410 participants (200 men 39+/-12 years old, and 210 women 35+/-10 years old) completed the Hostility and Direction of Hostility questionnaire (range 0-55) and had blood taken for the assessment of high sensitivity C--reactive protein, fibrinogen, white blood cell counts, and plasma homocysteine concentrations. RESULTS: 111 (27%) of the participants were classified in the upper quartile of the hostility scale (>21 score) and 119 (29%) were classified in the lower quartile (<11 score). Multivariate linear regression analysis revealed that hostility score associated positively only with homocysteine levels (standardized Beta=0.124, adj. R2=6%, p=0.015), after controlling for age, gender, educational status, body mass index, physical activity levels, and dietary habits of the participants. In particular, a 10-unit increase in the hostility scale was associated with a 2.9 micromol/l rise in homocysteine levels. CONCLUSIONS: Our findings suggest a positive relationship between homocysteine and hostility; however, whether hostility influences inflammation or the thrombotic process remains to be evaluated by future prospective studies.

Adult↗

Can a Mediterranean diet moderate the development and clinical progression of coronary heart disease? A systematic review.

BACKGROUND: It has been suggested that adherence to a Mediterranean diet reduces all causes of mortality, especially death rates due to coronary heart disease. In this review we summarize the findings of observational studies that evaluated the effect of the Mediterranean dietary pattern in the primary and secondary prevention of coronary heart disease. MATERIAL/METHODS: We retrieved published results from prospective and case-control studies which evaluated the association between adherence to a Mediterranean diet and the occurrence of coronary heart disease outcomes. RESULTS: The benefits from the Mediterranean diet were significant in all studies. The reduction in the risk of coronary heart disease varied from 8% to 45%, depending on the increment used by the investigators in the presentation of their results. CONCLUSIONS: The systematically reviewed studies reveal a cardio-protective effect of the Mediterranean diet and point to this dietary pattern as highly appropriate for public health objectives.

Coronary Disease↗

Adherence to the Mediterranean diet attenuates inflammation and coagulation process in healthy adults: The ATTICA Study.

OBJECTIVES: We studied the effect of the Mediterranean diet on plasma levels of C-reactive protein (CRP), white blood cell counts, interleukin (IL)-6, tumor necrosis factor (TNF)-alpha, amyloid A, fibrinogen, and homocysteine. BACKGROUND: To the best of our knowledge, the mechanism(s) by which the Mediterranean diet reduces cardiovascular risk are not well understood. METHODS: During the 2001 to 2002 period, we randomly enrolled 1,514 men (18 to 87 years old) and 1,528 women (18 to 89 years old) from the Attica area of Greece (of these, 5% of men and 3% of women were excluded because of a history of cardiovascular disease). Among several factors, adherence to the Mediterranean diet was assessed by a diet score that incorporated the inherent characteristics of this diet. Higher values of the score meant closer adherence to the Mediterranean diet. RESULTS: Participants who were in the highest tertile of the diet score had, on average, 20% lower CRP levels (p = 0.015), 17% lower IL-6 levels (p = 0.025), 15% lower homocysteine levels (p = 0.031), 14% lower white blood cell counts (p = 0.001), and 6% lower fibrinogen levels (p = 0.025), as compared with those in the lowest tertile. The findings remained significant even after various adjustments were made. Borderline associations were found regarding TNF-alpha (p = 0.076), amyloid A levels (p = 0.19), and diet score. CONCLUSIONS: Adherence to the traditional Mediterranean diet was associated with a reduction in the concentrations of inflammation and coagulation markers. This may partly explain the beneficial actions of this diet on the cardiovascular system.

Adolescent↗

Distribution of serum lipids and lipoproteins in patients with beta thalassaemia major; an epidemiological study in young adults from Greece.

BACKGROUND: Beta-thalassaemia major (b-TM) has been defined as a combination of chronic hemolytic anemia, iron storage disease and myocarditis, and it has been associated with premature death especially due to heart failure. To the best of our knowledge the status of blood lipids in these patients has rarely been investigated. Thus, we assessed the levels of lipids and lipoproteins in a sample of cardiovascular disease free adult men and women with b-TM. METHODS: During 2003 we enrolled 192 consecutive patients with b-TM that visited our Institution for routine examinations. The Institution is considered the major reference center for b-TM in Greece. Of the 192 patients, 88 were men (25 +/- 6 years old) and 104 women (26 +/- 6 years old). Fasting blood lipid levels were measured in all participants. RESULTS: Data analysis revealed that 4% of men and 2% of women had total serum cholesterol levels > 200 mg/dl, and 11% of men and 17% of women had triglyceride levels > 150 mg/dl. In addition, mean HDL cholesterol levels were 32 +/- 11 mg/dl in men and 38 +/- 10 mg/dl in women, lipoprotein-a levels were 8.3 +/- 9 mg/dl in men and 8.8 +/- 9 mg/dl in women, apolipoprotein-A1 levels were 111 +/- 17 mg/dl in men and 123 +/- 29 mg/dl in women, and apolipoprotein-B levels were 60 +/- 20 mg/dl in men and 59 +/- 14 mg/dl in women. Total-to-HDL cholesterol ratios were 3.7 +/- 1.2 and 3.8 +/- 1.5 in men and women, respectively. CONCLUSIONS: The majority of the patients had blood lipid levels (by the exception of HDL-cholesterol) within the normal range, and consequently the prevalence of lipid and lipoprotein abnormalities was much lower as compared to the general population of the same age. Interestingly, is that the total-to HDL cholesterol ratio was high in our patients, and may underline the importance of this index for the prognosis of future cardiac events in these patients.

Journal Article↗

Effect of exposure to secondhand smoke on markers of inflammation: the ATTICA study.

PURPOSE: We sought to investigate the effect of secondhand smoke exposure on inflammatory markers related to cardiovascular disease. METHODS: During 2001 to 2002, we randomly selected a stratified (age-sex) sample of adults without clinical evidence of cardiovascular disease. Exposure to secondhand smoke (>30 minutes per day and > or =1 day per week) was recorded. Multivariate regression analysis was used to evaluate the effects of exposure to secondhand smoke on levels of C-reactive protein, fibrinogen, homocysteine, and oxidized low-density lipoprotein (LDL) cholesterol, and on white blood cell count. RESULTS: One hundred and thirty-seven (38%) of the 357 men who had never smoked and 211 (33%) of the 638 never-smoking women reported current exposure to secondhand smoke. Compared with those who were not exposed to secondhand smoke, those exposed more than 3 days per week had higher white blood cell counts (by 600 cells per microL; P = 0.02), as well as higher levels of C-reactive protein (by 0.08 mg/dL; P = 0.03), homocysteine (by 0.4 micromol/L; P = 0.002), fibrinogen (by 5.2 mg/dL; P = 0.4), and oxidized LDL cholesterol (by 3.3 mg/dL; P = 0.03), after adjusting for several potential confounders. CONCLUSION: Our findings suggest another pathophysiological mechanism by which exposure to secondhand smoke is associated with the development of atherosclerosis.

Adult↗

Molecular characterization of familial hypercholesterolemia in German and Greek patients.

We used the denaturing gradient gel electrophoresis (DGGE) method to define mutations in the promoter region, the 18 exons, and their flanking intronic sequences of the low-density lipoprotein (LDL) receptor gene LDLR, causing familial hypercholesterolemia (FH) phenotype in 100 German and in 100 Greek hypercholesterolemic individuals. In addition, we tested all patients for the presence of mutations in codons 3456-3553 of the gene encoding apolipoprotein B-100 (APOB). Twenty-six aberrant DGGE patterns were identified and subsequently directly sequenced. In LDLR, two novel missense mutations (c.1957G>T/p.V653F, c.647 G>A/p.C216Y) and one novel homozygous base substitution c.1-156 C>T in the repeat 2 of the promoter region were identified among German FH patients; one novel splice site c.1060+10C>G was identified among Greek FH patients. One of the German FH patients was a carrier for the mutations c.1171G>A/p.A391T and p.V653F, and two of the Greek FH patients were compound heterozygotes for the mutations c.1150C>T/p.Q384X and c.1158C>G/p.D386E. Two German FH patients carried the mutation p.R3500Q within APOB. Comparing the mutations within the LDLR gene of the two European FH populations, the German population seems to be more heterogeneous than the Greek cohort. Further studies in progress are trying to elucidate the responsiveness to drug therapy in association with LDLR genotype and the nutritional habits of the two FH populations.

Adolescent↗

The association between coffee consumption and plasma total homocysteine levels: the "ATTICA" study.

The aim of this work was to investigate the association between homocysteine levels and coffee consumption in a sample of cardiovascular disease-free men and women. From May 2001 to December 2002, we randomly enrolled 1514 men and 1528 women, stratified by age and gender, from the greater area of Athens. Blood samples were collected in the fasting state. Among other investigated factors, dietary habits (including coffee consumption in ml per day, adjusted for 28% caffeine containment) were evaluated using a validated food frequency questionnaire. Men consumed higher quantities of coffee compared with women (250 +/- 55 vs 150 +/- 60 ml/day, P = 0.001), while homocysteine values were also higher in men than in women (14.5 +/- 6 vs 10.8 +/- 3.5 micromol/l, P = 0.001). A dose-response relationship of homocysteine levels with coffee consumption was observed (r = 0.10, P = 0.034). In particular, we found that homocysteine levels were 11.2 +/- 5 micromol/l for no consumption, 11.7 +/- 7 micromol/l for <100 ml/day, 12.5 +/- 7 micromol/l for 200-400 ml/day, and 12.7 +/- 4 micromol/l for >500 ml/day consumption (P = 0.018). The observed trend remained significant even after controlling for the interactions between coffee consumption with gender, smoking habits, physical activity status, and eating habits. However, the sole effect of the consumption of filtered coffee on homocysteine levels was significant only in those who consumed more than 500 ml/day (P = 0.043). Although our findings cannot be evidence for causality, they can be the basis for hypotheses about the relation between homocysteine and coffee that can partially explain the mechanisms by which elevated homocysteine levels may influence coronary risk.

Adult↗

Evidence for association between endothelial nitric oxide synthase gene polymorphism (G894T) and inflammatory markers: the ATTICA study.

BACKGROUND: We evaluated the effect of the point mutation of guanine to thymine at nucleotide position 894 (G894T) of the endothelial nitric oxide synthase (eNOS) gene on inflammatory and oxidative stress markers. METHODS: We studied genetic information from 270 men (18-87 years old) and 325 women (18-89 years old). Participants without any clinical evidence of cardiovascular or other atherosclerotic disease were randomly selected from the general population according to the age-sex distribution of Athens greater area. Genomic DNA was extracted from 2 to 5 mL of fresh or frozen whole blood using standard methods. RESULTS: The DNA analysis showed that 10.6% of the participants were Asp-homozygotes (Asp/Asp), 40% heterozygotes (Asp/Glu) and 49.4% Glu-homozygotes (Glu/Glu). Compared to Asp/Glu and Glu/Glu, Asp/Asp had higher levels of fibrinogen (332 +/- 46 or 329 +/- 33 vs 319 +/- 29 mg/dL, P =.029), white blood cells (6.9 +/- 0.6 or 6.5 +/- 0.3 vs 6.1 +/- 0.9 x 10(3) counts, P =.044), and oxidized low-density lipoprotein cholesterol (68 +/- 21 or 61 +/- 22 vs 59 +/- 20 mg/dL, P =.039), after controlling for several potential confounders. An insignificant association was found between homocysteine (P =.08), C-reactive protein (P =.096), and the distribution of G894T polymorphism (P <.1). No association between the distribution of the polymorphism and hypertension status of the participants was observed. CONCLUSIONS: Our results imply that G894T polymorphism of the endothelial nitric oxide synthase gene is associated with elevated levels of inflammatory and oxidative stress markers, which may partially explain the increased prevalence of G894T polymorphism among patients with cardiovascular disease.

Adolescent↗

The effect of Ca2+ channel antagonists on plasma concentrations of matrix metalloproteinase-2 and -9 in essential hypertension.

The ability of some antihypertensive drugs to protect from vascular damage in hypertension might be partially due to their ability to control matrix metalloproteinase (MMP)-mediated extracellular matrix metabolism, which in turn may contribute to vascular remodeling. This study was designed to investigate whether treatment with felodipine or diltiazem has any effect on plasma levels of MMP-2 and MMP-9 in essential hypertensive patients. We measured plasma levels of active MMP-2 and MMP-9 in 72 hypertensive subjects and 45 controls, both before and after 6 months of treatment with felodipine (group A) or diltiazem (group B). Mean adjusted differences, before and after each treatment, for MMP-2 and MMP-9 levels were: 19.8 (P =.01) for MMP-2, 0.2 (P =.5) for MMP-9 (group A), and 1.4 (P =.4) for MMP-2, 0.2 (P =.7) for MMP-9 (group B). These findings show that MMP-2 level is raised by treatment with felodipine but not diltiazem, whereas MMP-9 is unaffected by either treatment.

Adult↗

Association between prehypertension status and inflammatory markers related to atherosclerotic disease: The ATTICA Study.

BACKGROUND: We sought to evaluate the association between prehypertension status and inflammatory markers (C-reactive protein, white blood cells, interleukin-6, tumor necrosis factor-alpha, amyloid-a, homocysteine, and fibrinogen), in a random sample of cardiovascular disease-free adults. METHODS: The ATTICA study is a cross-sectional population-based survey conducted in the Attica region during 2001 to 2002. Based on a multistage and stratified random sampling, 1514 men and 1528 women (18 to 89 years old) were enrolled. The survey included a detailed interview, blood samples collected after 12 h of fasting, and, among other clinical measurements, status of blood pressure levels. RESULTS: The prehypertensive population included 653 men (43%) and 535 women (35%). Compared to normotensives, prehypertensive men and women had 31% higher C-reactive protein (P <.01), 32% higher tumor necrosis factor-alpha (P <.05), 9% higher amyloid-a (P <.05), 6% higher homocysteine levels (P <.01), and a 10% higher white blood cell counts (P <.05), after correcting for multiple comparisons and adjusting for age, body mass index, blood lipids, glucose, food groups consumed, and other potential confounders. CONCLUSIONS: Studying a large sample of cardiovascular disease-free adults, we revealed an association between prehypertension and inflammatory markers linked to the atherosclerotic process, independently of other coexisting risk factors or unhealthy lifestyle behaviors. Our findings may be of clinical importance, as they suggest that prehypertension might be a pro-inflammatory condition.

Adolescent↗

Status and management of blood lipids in Greek adults and their relation to socio-demographic, lifestyle and dietary factors: the ATTICA Study. Blood lipids distribution in Greece.

OBJECTIVE: In this work, we assessed the status and management of blood lipids in a sample of cardiovascular disease free adult men and women from Greece. We also evaluated the effect of several socio-demographic, dietary and lifestyle habits on lipid levels. METHODS: The ATTICA Study is a population-based cohort that has randomly enrolled 1128 men and 1154 women (aged >18 years old), stratified by age-gender, from the greater area of Athens, during 2001-2002. Adherence to Mediterranean diet was assessed through a diet score that was based on a validated food-frequency questionnaire. RESULTS: Forty-six percent of men and 40% of women had total serum cholesterol levels >200mg/dl. Of them, 40% of men and 30% of women were unaware of their condition. Twenty-one percent of men and 7% of women had HDL-cholesterol levels <35 mg/dl. Twenty-eight percent of men and 13% of women had triglyceride levels >150 mg/dl. Fifteen percent of men and 12% of women had LDL-cholesterol levels >160 mg/dl and 52% of men and 48% of women had LDL >130 mg/dl. Of those who had known blood lipid abnormalities, 36% of men and 33% of women followed a dietary medication, 31% of men and 20% of women were receiving a pharmaceutical treatment (mainly statin) and the rest were untreated. Participants who adopted the Mediterranean diet and received statin, had on average 9% lower total cholesterol (P = 0.04), 19% lower LDL-cholesterol levels (P = 0.02) and 32% lower oxidized LDL-cholesterol levels (P < 0.001) compared to those who were untreated and adopted a Westernized diet. CONCLUSIONS: We could speculate that about 3 million Greek adults had high total cholesterol levels. Adverse findings were also observed regarding the other investigated blood lipids. Mediterranean diet could be a complimentary mean to pharmaceutical treatment in reducing blood lipids.

Adult↗

Inflammation, coagulation, and depressive symptomatology in cardiovascular disease-free people; the ATTICA study.

BACKGROUND: Depression is associated with an increase in cardiovascular disease, but the underlying mechanisms are not well understood. The aim of this study was to examine the associations of depressive symptoms with inflammation and coagulation factors related to cardiovascular risk in persons free of cardiovascular disease. METHODS: A random algorithm was developed and stratified by gender-age and multistage sampling was performed during 2001-2002. In this study, we analysed data from 453 men (19-89 years old) and 400 women (18-84 years old). Inflammation markers were C-reactive protein (CRP), serum amyloid A, white blood cell (WBC) and total platelet counts; and coagulation factors including homocysteine and fibrinogen. Depression was assessed with the Zung Self-Rating Depression Scale (ZDRS range 0-100) after validation for the study population. A ZDRS score of 50 or more classified a person as mildly depressive. Statistical adjustments were made for risk factors (age, gender, smoking, diabetes mellitus, and physical activity level). RESULTS: Women had significantly higher scores on the Zung depression scale than men (47 +/- 9 vs. 43 +/- 10, p<0.001). Thus, 21% of men and 27% of women had mild depression, while 4% of men and 6% of women had severe depressive symptomatology. The depression scale correlated positively with C-reactive protein levels (p<0.05), white blood cell count (p<0.05), and fibrinogen (p<0.05) in both genders after adjustment for control variables. CONCLUSION: This study revealed that depression was associated with inflammation and coagulation factors in cardiovascular disease-free people, suggesting a possible pathway leading to an increased frequency of events of coronary heart disease in depressive individuals.

Adolescent↗

Climatological variations in daily hospital admissions for acute coronary syndromes.

OBJECTIVE: We examined the association between climatologic parameters and daily admissions for non-fatal acute coronary syndromes (ACS) to emergency units of hospitals in the greater Athens area, from January 2001 to August 2002. METHODS: Daily mean, maximum and minimum temperatures, relative humidity, wind speed, barometric pressure and a thermo-hydrological index (T.H.I.) were measured at the meteorological station of the Laboratory of Climatology of the Geology Department of the University of Athens. In addition, the daily number of admissions for acute myocardial infarction or unstable angina in the five major general hospitals in the greater Athens area was recorded. Generalized additive models (GAM) were applied to regress-time-series of daily numbers of outpatients with acute cardiac events against climatological variations, after controlling for possible confounders and adjustment for over dispersion and serial correlation. RESULTS: Five thousand four hundred fifty-eight Athenians with non-fatal acute cardiac events were admitted to the selected hospitals during the period of the study, 4093 (75%) males and 1365 (25%) females. There was a negative correlation between hospital admissions and mean daily temperature (MDT) with a 1 degrees C decrease in mean air temperature yielding a 5% increase in hospital admissions (P<0.05). This association was stronger in females and the elderly (P<0.01). Relative humidity was positively correlated with hospital admissions (P<0.05). CONCLUSION: Despite the relatively short study period (<2 years), these findings suggest a significant association between cold weather and increased coronary heart disease incidence, especially in the elderly and females.

Adult↗

Impact of lifestyle habits on the prevalence of the metabolic syndrome among Greek adults from the ATTICA study.

BACKGROUND: Individuals with the metabolic syndrome (MS) are at high risk for coronary heart disease and may benefit from aggressive lifestyle modification. In this study, we evaluated the effect of leisure time physical activity (PA) and the Mediterranean diet (MD) on the prevalence of the MS. METHODS: The ATTICA study is a health and nutritional survey. On the basis of a multistage, random sampling, 1128 men and 1154 women (>18 years old) without any evidence of cardiovascular disease or diabetes mellitus were enrolled from the greater Athens area during 2001 to 2002. The MS was defined according to the National Cholesterol Education Program (NCEP) Adult Treatment Panel (ATP) III criteria. PA was determined from a detailed questionnaire and graded according to the kcal/min expanded. MD was assessed through a validated nutrient questionnaire. RESULTS: The overall prevalence of the MS was 453 of 2282 subjects (19.8%). Of these subjects, 284 (25.2%) were men and 169 (14.6%) were women (P <.001). The prevalence of the MS increased accordingly to age (P for trend <.001). With multiple logistic regression analysis, the odds ratio of having the MS when the participant consumed the MD was 0.81 (95% CI, 0.68-0.976), and when even a little to moderate PA (<7 kcal/min)was reported, the odds ratio was 0.75 (95% CI, 0.65-0.86). The higher levels of inflammation and coagulation markers among participants with MS did not explain much of the aforementioned effect of lifestyle modification. CONCLUSION: MS is common in Greece and is becoming even more common in the middle-aged population. The suggested therapeutic lifestyle approach may contribute to the reduction of the prevalence of the MS, beyond the levels of several lipid, inflammation, and coagulation markers.

Adult↗