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BACKGROUND: Questions remain concerning to what extent age and sex may modify the suggested association between psoriasis and the metabolic syndrome in the general population. OBJECTIVES: To investigate the association between psoriasis and the metabolic syndrome within a large population-based cohort by age and sex. METHODS: A cross-sectional study including 10 521 participants aged 30-79 years from the Tromsø Study cohort was performed; 1137 participants reported lifetime psoriasis of a mainly mild character. The new harmonized definition of metabolic syndrome was used in the multivariable logistic regression analysis. RESULTS: There was a uniformly higher prevalence of metabolic syndrome in men and women with psoriasis compared with those without across all age groups. In women, psoriasis was associated with a 3·8-times higher odds of metabolic syndrome at age 30 years (95% confidence interval 1·5-9·7), with a decreasing odds ratio with increasing age. In men, psoriasis was associated with a stable 1·35-times higher odds of metabolic syndrome (95% confidence interval 1·1-1·6) at all ages. Abdominal obesity was the most frequent metabolic syndrome component in women in this study, and there was indication of a dose-response relationship between psoriasis severity, indicated through treatment, and having a high waistline in women. CONCLUSIONS: This study suggests age and sex variations in the risk of metabolic syndrome among individuals with psoriasis. Given the high prevalence of psoriasis and the significantly elevated burden of metabolic syndrome in this patient group, there may be a benefit from targeted screening of metabolic syndrome among individuals with psoriasis regardless of age and disease severity.

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Increased antioxidant defences are hypothesised to decrease age- and smoking-related decline in lung function. The relationship between dietary antioxidants, smoking and forced expiratory volume in 1 s (FEV(1)) was investigated in community-dwelling older adults in the Health, Aging and Body Composition study. 1,443 participants completed a food frequency questionnaire, self-reported smoking history and had measurements taken of FEV(1) at both baseline and after 4 yrs of follow-up. The association of dietary intake of nutrients and foods with antioxidant properties and rate of FEV(1) decline was investigated using hierarchical linear regression models. In continuing smokers (current smokers at both time-points), higher vitamin C intake and higher intake of fruit and vegetables were associated with an 18 and 24 mL · yr(-1) slower rate of FEV(1) decline compared with a lower intake (p < 0.0001 and p = 0.003, respectively). In quitters (a current smoker at study baseline who had quit during follow-up), higher intake was associated with an attenuated rate of decline for each nutrient studied (p ≤ 0.003 for all models). In nonsmoking participants, there was little or no association of diet and rate of decline in FEV(1). The intake of nutrients with antioxidant properties may modulate lung function decline in older adults exposed to cigarette smoke.

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OBJECTIVES: Increased breast cancer risk has been observed with both low folate status and a functional polymorphism in methylenetetrahydrofolate reductase (MTHFR 677C --> T). Cytoplasmic serine hydroxymethyltransferase (cSHMT) affects the flow of one-carbon units through the folate metabolic network, but there is little research on a role for genetic variation in cSHMT in determining breast cancer risk. METHODS: A nested case-control study within the Nurses' Health Study was used to investigate an association between cSHMT (1420C --> T) and breast cancer risk. RESULTS: No evidence for an association between the cSHMT genotype and breast cancer was observed. There was also no evidence of a gene-gene interaction between cSHMT and MTHFR. CONCLUSIONS: There was no evidence of an association between the cSHMT genotype and breast cancer occurrence. Further research in populations with differing average folate intake may be required to fully understand the interactions of folate nutrition, sequence variation in folate genes and breast cancer risk.

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BACKGROUND: Observational epidemiological studies of dietary antioxidant intake, serum antioxidant concentration and lung outcomes suggest that lower levels of antioxidant defences are associated with decreased lung function. Another approach to understanding the role of oxidant/antioxidant imbalance in the risk of chronic obstructive pulmonary disease (COPD) is to investigate the role of genetic variation in antioxidant enzymes, and indeed family based studies suggest a heritable component to lung disease. Many studies of the genes encoding antioxidant enzymes have considered COPD or COPD related outcomes, and a systematic review is needed to summarise the evidence to date, and to provide insights for further research. METHODS: Genetic association studies of antioxidant enzymes and COPD/COPD related traits, and comparative gene expression studies with disease or smoking as the exposure were systematically identified and reviewed. Antioxidant enzymes considered included enzymes involved in glutathione metabolism, in the thioredoxin system, superoxide dismutases (SOD) and catalase. RESULTS: A total of 29 genetic association and 15 comparative gene expression studies met the inclusion criteria. The strongest and most consistent effects were in the genes GCL, GSTM1, GSTP1 and SOD3. This review also highlights the lack of studies for genes of interest, particularly GSR, GGT and those related to TXN. There were limited opportunities to evaluate the contribution of a gene to disease risk through synthesis of results from different study designs, as the majority of studies considered either association of sequence variants with disease or effect of disease on gene expression. CONCLUSION: Network driven approaches that consider potential interaction between and among genes, smoke exposure and antioxidant intake are needed to fully characterise the role of oxidant/antioxidant balance in pathogenesis.

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BACKGROUND: A reduced dietary intake of n-3 fatty acids, in association with increased n-6 fatty acid intake, has been proposed as a potential aetiological factor for chronic obstructive pulmonary disease (COPD) and asthma. However, the relative importance of individual fatty acids within the n-3 and n-6 categories on this effect has not been widely investigated. We have studied the relation between individual fatty acid intakes, lung function and self-reported respiratory symptoms and diagnoses in a representative sample of more than 13,000 Dutch adults. METHODS: Intake of individual fatty acids was estimated by a food frequency questionnaire and analysed in relation to measures of forced expiratory volume in 1 s (FEV1) and to questionnaire reported wheeze, asthma and COPD symptoms. RESULTS: After adjusting for confounding, we found no protective association between individual n-3 fatty acid intakes and FEV1. Higher intakes of some n-6 fatty acids were associated with lower FEV1, this effect being most marked for c22:4 n-6 docosatetraenoic acid (reduction in FEV1 between the highest and lowest quintile of intake 54.5 ml (95% CI -81.6 to -27.4)). Most of the n-6 fatty acid effects interacted significantly with smoking, their effects being strongest in current smokers. Individual n-3 fatty acid intakes were generally associated with a higher risk of wheeze in the past year, but otherwise there was little or no association between fatty acid intake and wheeze, doctor diagnosed asthma or other respiratory symptoms. CONCLUSIONS: A high intake of n-3 fatty acids does not appear to protect against COPD or asthma, but a high intake of several n-6 fatty acids is associated with a significant reduction in FEV1, particularly in smokers. These findings indicate that high dietary intake of n-6 fatty acids, rather than reduced n-3 intake, may have an adverse effect on lung health.

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OBJECTIVE: The objective of this study was to investigate the association between antioxidant nutrients and markers of oxidative stress with pulmonary function in persons with chronic airflow limitation. DESIGN: Cross-sectional study exploring the association of antioxidant nutrients and markers of oxidative stress with forced expiratory volume in the first second (FEV1%) and forced vital capacity (FVC%). SETTING/SUBJECTS: The study data included 218 persons with chronic airflow limitation recruited randomly from the general population of Erie and Niagara counties, New York State, USA. RESULTS: After adjustment for covariates, multiple linear regression analysis showed that serum beta-cryptoxanthin, lutein/zeaxanthin, and retinol, and dietary beta-carotene, beta-cryptoxanthin, lutein/zeaxanthin, vitamin C, and lycopene were positively associated with FEV1% (P < 0.05, all associations). Serum vitamins beta-cryptoxanthin, lutein/zeaxanthin, and lycopene, and dietary beta-cryptoxanthin, beta-carotene, vitamin C, and lutein/zeaxanthin were positively associated with FVC% (P < 0.05, all associations). Erythrocytic glutathione was negatively associated with FEV1%, while plasma thiobarbituric acid-reactive substances (TBARS) were negatively associated with FVC% (P < 0.05). CONCLUSION: These results support the hypothesis that an imbalance in antioxidant/oxidant status is associated with chronic airflow limitation, and that dietary habits and/or oxidative stress play contributing roles.

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To evaluate whether items from 3 brief measures of fruit and vegetable consumption were understood and interpreted as intended, cognitive testing was conducted in a purposive sample of 31 white, African-American and Hispanic persons. The measurement instruments tested were the fruit and vegetable module from the Behavioral Risk Factor Surveillance System (to measure frequency), and 1 fruit and 1 vegetable variety measurement instrument developed by the investigators. The cognitive testing interviews were analyzed qualitatively to identify interpretation difficulties and other measurement issues. The testing identified a number of measurement issues, including issues related to time frame, wording, interpretation, grouping of items, and serving size. Recommendations based on the findings were incorporated into revised versions of each instrument, which were further tested in a small sample. As revised and presented in this article, these instruments for assessing fruit and vegetable frequency and variety appear to be understood and interpreted as intended across different racial and ethnic groups, and may be useful in situations requiring brief dietary assessment, although further testing is needed.

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Recent studies of chronic obstructive pulmonary disease have raised interest in its relation to nutrition. Several dietary antioxidants have been positively associated with lung function in healthy, general population samples. This study considered the separate and joint effects of vitamin C, vitamin E, beta-carotene, and selenium intake and used both dietary assessment and serum biomarkers of antioxidant status. The authors used data from the Third National Health and Nutrition Examination Survey comprising a sample representative of the US population in 1988-1994 (n = 18,162 subjects aged > or =17 years). Multiple linear regression analysis examined the separate and joint effects of the antioxidants on the ratio of forced expiratory volume in the first second (FEV1)/height2 adjusted for covariates. Each of the dietary and serum antioxidant nutrients was significantly associated with FEV1. When they were considered simultaneously (dietary and serum variables considered in separate models), independent associations were observed for most nutrients. Serum beta-carotene was less positively associated with FEV1 in smokers than nonsmokers, while serum selenium had a stronger positive association with FEV1 in smokers. The authors found that higher levels of antioxidant nutrients are associated with better lung function. The finding that the antioxidants differ in both their overall association with lung function and in whether this association varies by smoking status has implications for further research.

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The relation between dietary vitamin C intake and pulmonary function was investigated in a cross-sectional study carried out in 69 counties in rural China in 1989. Within each of the 69 counties, 120 subjects aged 35-64 years were identified using a three-stage random clustering procedure. Each subject underwent pulmonary function testing, completed a detailed questionnaire, and provided a blood sample. Dietary vitamin C intakes were estimated among half of the subjects using a 3-day weighed record of household food intake. Plasma vitamin C was measured in sex-specific blood pools created from individual samples in each geographic area. Among the 3,085 subjects for whom there were complete data, dietary intake of vitamin C (151 mg/day (standard deviation, 111)) was significantly related to forced expiratory volume in the first second (FEV1) and forced vital capacity after adjustment for sex, age, height, weight, total caloric intake, tobacco smoking, and education. An increase of 100 mg/day in vitamin C intake was associated with an increase of 21.6 ml (95% confidence interval -0.4 to 43.5) in FEV1 and an increase of 24.9 ml (95% confidence interval 0.2 to 49.6) in forced vital capacity. No significant interaction with smoking status was observed. A significant positive association was also observed at the geographic level, between county-pooled plasma vitamin C and mean FEV1. These data support the hypothesis that dietary vitamin C may protect against the loss of pulmonary function.

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The purpose of this study was to examine the relationship of body mass index, abdomen-hip ratio, and dietary intake to fasting and postprandial insulin concentrations among 652 men aged 43-85 y, followed in the Normative Aging Study. Log-transformed fasting insulin was significantly associated with body mass index, abdomen-hip ratio, total fat energy, and saturated fatty acid energy, with correlation coefficients ranging from 0.14 for total fat to 0.45 for body mass index. When multivariate models were used, body mass index, abdomen-hip ratio, and saturated fatty acid intake were statistically significant independent predictors of both fasting and postprandial insulin concentrations, after age, cigarette smoking, and physical activity were adjusted for. If saturated fatty acids as a percentage of total energy were to decrease from 14% to 8%, there would be an 18% decrease in fasting insulin and a 25% decrease in postprandial insulin. These data suggest that overall adiposity, abdominal obesity, and a diet high in saturated fatty acids are independent predictors for both fasting and postprandial insulin concentrations.

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The relation between the abdominal accumulation of body fat, total-body adiposity, and blood glucose level and the risk of non-insulin-dependent diabetes mellitus was evaluated prospectively among 1,972 male participants in the Department of Veterans Affairs Normative Aging Study cohort. The risk of non-insulin-dependent diabetes mellitus was assessed by means of the proportional hazards model; 226 cases of diabetes occurred among the 1,972 men (mean age at entry, 41.9 years; range, 22-80 years) over 35,496 person-years of observation. The relation of body mass index to diabetes risk was partly explained by body fat distribution; after adjusting for age, the ratio of abdominal circumference to hip breadth, and cigarette smoking, men in the top tertile for body mass index had a 1.3-fold greater risk of diabetes than did men in the lowest tertile (95% confidence interval 0.9-1.8). Moreover, after adjusting for age, body mass index, and cigarette smoking, men in the top tertile for the ratio of abdominal circumference to hip breadth had a 2.4-fold greater risk of diabetes than did men in the lowest tertile (95% confidence interval 1.7-3.7). When blood glucose was analyzed as a continuous outcome variable, the findings were consistent, i.e., a positive association with abdominal fat independent of total-body adiposity. These results confirm previous reports of a prospective relation between abdominal adiposity and the risk of diabetes and provide prospective evidence of a relation between blood glucose levels and both body fat distribution and obesity.

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The relation between the abdominal accumulation of body fat, blood pressure, and hypertension was assessed prospectively among 1972 male participants in the Veterans Administration Normative Aging Study. Body mass index (BMI = weight [kg]/height [m]2) and the ratio of abdominal circumference to hip breadth (AC/HB), measured at regular exams, were used as indices of total adiposity and body fat distribution, respectively. Considering blood pressure as a continuous outcome variable (in models that allowed for intraclass correlation), the AC/HB ratio was significantly positively associated with both diastolic and systolic blood pressure (P < 0.001), adjusting for age and BMI. Blood pressure was dichotomized and hypertension risk was assessed using the proportional hazards model, adjusting for age and BMI. Seven hundred cases of hypertension were recorded by study physicians during 35,496 person-years of follow-up. The risk of hypertension increased approximately three-fold (95% confidence interval, 1.7 to 5.2) with a change of one unit in the AC/HB ratio. These estimates were little changed when the effects of smoking and alcohol intake were considered. Thus, the abdominal accumulation of body fat, apart from overall level of adiposity, was associated with both increased blood pressure and an increased risk of hypertension.

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The case-control study of febrile seizures in childhood described here, comprising 472 case-control pairs in western Washington, was designed to investigate the importance of prenatal exposures as risk factors for febrile seizures and to determine the degree to which two clinical subtypes of febrile seizures (simple and complex) have different risk factors. Maternal cigarette smoking and alcohol intake during pregnancy were associated with the risk of a febrile seizure in the child. Prenatal maternal cigarette smoking was associated with a twofold increase in the risk of a simple febrile seizure (95% confidence interval 1.2-3.4), and a strong dose-response relation was found. This association could not be explained by maternal demographic variables, maternal alcohol intake, child's birth weight, or childhood medical history variables. Prenatal maternal alcohol intake was associated with a twofold increase in the risk of a complex febrile seizure (95% confidence interval 1.3-3.8), and a strong dose-response relation was present. This association could not be explained by maternal age, race, education, or cigarette smoking. These results suggest that curtailment of smoking and alcohol consumption during pregnancy, a measure already widely prescribed during pregnancy, may also be an effective means of preventing childhood febrile seizures.

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Body fat distribution may be a more specific marker than obesity for risk of cardiovascular disease and diabetes. The relationship between body fat distribution and sitting systolic and diastolic blood pressure was examined in a cross-sectional analysis of 1936 normotensive men aged 21 to 80 years. In this analysis body fat distribution was represented by the ratio of abdomen circumference to hip breadth (denoted as WHbR). Pearson product-moment correlations adjusted for age revealed a positive correlation between WHbR and both systolic and diastolic blood pressure (r = 0.13 and r = 0.14, respectively). In a multiple linear regression model controlling for age, smoking status and body mass index (BMI), WHbR was associated with systolic blood pressure [regression coefficient (standard error) = 3.58 (1.8), P = 0.048)], but had much less of an association with diastolic blood pressure [regression coefficient (standard error) = 1.90 (1.3), P = 0.141]. Further adjustment for alcohol intake decreased the association between WHbR and systolic blood pressure [regression coefficient (standard error) = 2.90 (1.81), P = 0.110]. Body fat distribution, as represented by WHbR was associated with level of systolic blood pressure independently of overall level of obesity (BMI) in normotensive men; adjustment for alcohol intake attenuated the relationship. These data suggest that dietary factors, notably alcohol intake, may influence the effect of body fat distribution on blood pressure.

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To determine whether the cytohormonal status of postmenopausal women with cancer involving the uterus and vagina differs from that of women free of cancer, 100 women 60 years of age or older with positive cervicovaginal smears were compared with an age-matched control group without malignant neoplasms. Epidermoid carcinoma was identified in 64 patients (average age: 67 years) and adenocarcinoma in 34 patients (average age: 69 years). One patient had leiomyosarcoma, and another had bladder carcinoma. The paucity of benign squamous cells in the smears precluded hormonal evaluation in 32% of the index cases; the smears from 10% of the controls were also indeterminate. Of the evaluable cases with epidermoid carcinoma of the cervix, a high maturation was noted in 46% as compared to 11% for the matched controls. In addition, high maturation was noted in 69% of those patients with endometrial adenocarcinoma as compared to 19% for the matched controls. None of the index cases were atrophic; 31% of the controls were. A history of exogenous estrogen usage was obtained in three patients with endometrial adenocarcinoma, all with high maturation, and in five controls, none with high maturation. These data appear to indicate a difference in the cytohormonal status of patients with cervical or endometrial carcinoma as compared to those without; consequently, cytologists should be especially attentive to smears showing high maturation from postmenopausal women.

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