Showing papers by "Ioanna Tzoulaki published in 2008"
TL;DR: An examination of possible biological mechanisms indicates that the most likely causative effect of radiation exposure is damage to endothelial cells and subsequent induction of an inflammatory response, although it seems unlikely that this would extend to low and moderate doses (<5 Gy) of ionizing radiation and late-occurring cardiovascular disease.
Abstract: Little, M. P., Tawn, E. J., Tzoulaki, I., Wakeford, R., Hildebrandt, G., Paris, F., Tapio, S. and Elliott, P. A Systematic Review of Epidemiological Associations Between Low and Moderate Doses of Ionizing Radiation and Late Cardiovascular Effects, and Their Possible Mechanisms. Radiat. Res. 169, 99-109 (2008). The link between high doses of ionizing radiation and damage to the heart and coronary arteries is established. In this paper, we systematically review the epidemiological evidence for associations between low and moderate doses (<5 Gy) of ionizing radiation and late-occurring cardiovascular disease. Risks per unit dose in epidemiological studies vary over at least two orders of magnitude, possibly a result of confounding factors. An examination of possible biological mechanisms indicates that the most likely causative effect of radiation exposure is damage to endothelial cells and subsequent induction of an inflammatory response, although it seems unlikely that this would extend to low-dose and low-dose-rate exposure. However, a role for somatic mutation has been proposed that would indicate a stochastic effect. In the absence of a convincing mechanistic explanation of epidemiological evidence that is less than persuasive at present, a cause-and-effect interpretation of the reported statistical associations cannot be reliably inferred, although neither can it be reliably excluded. Further epidemiological and biological evidence will allow a firmer conclusion to be drawn.
167 citations
TL;DR: Systemic low-grade inflammation may lie on the causal pathway that relates impaired fetal growth and weight gain from childhood to adulthood to adverse adult cardiovascular health, and lifestyle changes from early life might be an important step in reducing cardiovascular risk in adults.
Abstract: AIMS: Low-grade inflammation might mediate associations between size at birth, early life growth, excessive weight gain, and subsequent risk of cardiovascular disease in adult life. Our aim was to investigate relationships between fetal growth, weight over the life course, and low-grade inflammation measured by serum high sensitivity C-reactive protein (CRP) levels at 31 years. METHODS AND RESULTS: General population-based northern Finland 1966 Birth Cohort study of 5840 participants attending a clinical examination at 31 years, including measurement of CRP. Weight and height were assessed at birth, 12 months, and 14 and 31 years of age. CRP levels at 31 years were 16% [95% confidence interval (CI) 8, 23] higher per 1 kg lower birth weight, 21% (95% CI 2, 37) higher per 10 cm lower birth length, and 24% (95% CI 10, 36) higher per 1 kg/m3 lower ponderal index, after adjustment for potential confounders. Participants with highest tertile body mass index (BMI) at 31 years and lowest tertile birth weight had the highest average CRP levels. Per unit increase in BMI from 14 to 31 years was associated with 16% (95% CI 14, 17) higher CRP levels; the association was larger for those in the top BMI tertile at age 14 years. CONCLUSION: Systemic low-grade inflammation may lie on the causal pathway that relates impaired fetal growth and weight gain from childhood to adulthood to adverse adult cardiovascular health. Lifestyle changes from early life might be an important step in reducing cardiovascular risk in adults.
102 citations
TL;DR: Non-haem iron has a possible role in the prevention and control of adverse blood pressure levels and an unfavourable effect of red meat on blood pressure was observed.
Abstract: Objective To investigate associations of dietary iron (total, haem, and non-haem), supplemental iron, and red meat with blood pressure. Design Cross sectional epidemiological study. Setting 17 population samples from Japan, China, the United Kingdom, and the United States participating in the international collaborative study on macro-/micronutrients and blood pressure (INTERMAP). Participants 4680 adults aged 40-59. Main outcome measure Average of eight blood pressure readings. Results In multiple linear regression analyses dietary total iron and non-haem iron were consistently inversely associated with blood pressure. With adjustment for potential non-dietary and dietary confounders, dietary total iron intake higher by 4.20 mg/4.2 MJ (2 SD) was associated with −1.39 mm Hg (P Conclusion Non-haem iron has a possible role in the prevention and control of adverse blood pressure levels. An unfavourable effect of red meat on blood pressure was observed. These results need confirmation including in prospective studies, clinical trials, and from experimental evidence on possible mechanisms.
94 citations
TL;DR: Dietary linoleic acid intake may contribute to prevention and control of adverse blood pressure levels in general populations and should be considered as a potential source of concern for public health reasons.
Abstract: Findings from observational and interventional studies on the relationship of dietary linoleic acid, the main dietary polyunsaturated fatty acid, with blood pressure have been inconsistent. The International Study of Macro-Micronutrients and Blood Pressure is an international cross-sectional epidemiological study of 4680 men and women ages 40 to 59 years from 17 population samples in China, Japan, United Kingdom, and United States. We report associations of linoleic acid intake of individuals with their blood pressure. Nutrient intake data were based on 4 in-depth multipass 24-hour dietary recalls per person and 2 timed 24-hour urine collections per person. Systolic and diastolic blood pressures were measured 8 times at 4 visits. With several models to control for possible confounders (dietary or other), linear regression analyses showed a nonsignificant inverse relationship of linoleic acid intake (percent kilocalories) to systolic and diastolic blood pressure for all of the participants. When analyzed for 2238 "nonintervened" individuals (not on a special diet, not consuming nutritional supplements, no diagnosed cardiovascular disease or diabetes, and not taking medication for high blood pressure, cardiovascular disease, or diabetes), the relationship was stronger. With adjustment for 14 variables, estimated systolic/diastolic blood pressure differences with 2-SD higher linoleic acid intake (3.77% kcal) were –1.42/–0.91 mm Hg (P<0.05 for both) for nonintervened participants. For total polyunsaturated fatty acid intake, blood pressure differences were –1.42/–0.98 mm Hg (P<0.05 for both) with 2 SD higher intake (4.04% kcal). Dietary linoleic acid intake may contribute to prevention and control of adverse blood pressure levels in general populations.
82 citations
01 Jan 2008
TL;DR: The majority of patients with IC experience stabilization of their symptoms within 5 years and only 10–15% ever develop critical limb ischemia, and both claudicants and those with asymptomatic disease are at increased risk of systemic cardiovascular events.
Abstract: Peripheral arterial disease (PAD) is a manifestation of atherosclerotic disease in the arteries to the legs. The clinical presentation of PAD includes a spectrum that spans individuals with asymptomatic disease, those who experience intermittent claudication (IC), and those with more severe symptoms of critical limb ischemia. PAD is a common condition that affects a large proportion of the adult population worldwide. The estimated prevalence of claudication ranges from 0.4% to 14.4%. The prevalence of asymptomatic disease diagnosed with noninvasive tests is much higher and ranges between 0.9% and 22% with the ratio of symptomatic to asymptomatic ranging between 1:0.9 and 1:6. Risk factors for atherosclerosis such as age, cigarette smoking, diabetes, dyslipidemia, and hypertension increase the likelihood of developing lower extremity PAD. The majority of patients with IC experience stabilization of their symptoms within 5 years and only 10–15% ever develop critical limb ischemia. Both claudicants and those with asymptomatic disease are at increased risk of systemic cardiovascular events.
1 citations
01 Jan 2008
1 citations
01 Jan 2008
TL;DR: This international collaborative study on macro-/ micronutrients and blood pressure (INTERMAP) is investigating association of dietary iron, supplemental iron, and red meat with blood pressure in adults from Japan, China, the United Kingdom, and the United States.
Abstract: Objective To investigate associationsof dietary iron (total, haem, and non-haem), supplemental iron, and red meat with blood pressure. Design Cross sectional epidemiological study. Setting 17 population samples from Japan, China, the UnitedKingdom,and theUnitedStatesparticipating in the international collaborative study on macro-/ micronutrients and blood pressure (INTERMAP). Participants 4680 adults aged 40-59. Main outcome measure Average of eight blood pressure