Post-diagnosis physical activity and survival after breast cancer diagnosis: the Long Island Breast Cancer Study

Physical activity (PA) is associated with physiological responses thought to beneficially affect survival after breast cancer diagnosis, yet few studies have considered the entire survivorship experience. Effects of post-diagnosis activity on survival were examined in a cohort of 1,423 women diagnosed with in situ or invasive breast cancer in 1996-1997. Subjects were interviewed soon after diagnosis and again after approximately 5 years to assess breast cancer-related factors, including recreational PA before and after diagnosis. Date and cause of death through 2009 were determined from the National Death Index. Adjusted estimates were obtained using proportional hazards regression and a selection model to account for missing data. Survival was improved among women who were highly active after diagnosis (>9.0 MET h/week) compared to inactive women (0 MET h/week) for all-cause [hazard ratio (HR) (95 % credible interval): 0.33 (0.22, 0.48)] and breast cancer-specific mortality [HR: 0.27 (0.15, 0.46)]. The association of PA with overall mortality appeared stronger in the first 2 years after diagnosis [HR: 0.14 (0.03, 0.44)] compared to 2+ years since diagnosis [HR: 0.37 (0.25, 0.55)]. These findings show that post-diagnosis PA is associated with improved survival among women with breast cancer.

Associations of red meat, fat, and protein intake with distal colorectal cancer risk

Studies have suggested that red and processed meat consumption elevate the risk of colon cancer; however, the relationship between red meat, as well as fat and protein, and distal colorectal cancer (CRC) specifically is not clear. We determined the risk of distal CRC associated with red and processed meat, fat, and protein intakes in Whites and African Americans. There were 945 cases (720 White, 225 African American) of distal CRC and 959 controls (800 White, 159 African American). We assessed dietary intake in the previous 12 mo. Multivariate logistic regression analyses were used to obtain odds ratios (OR) and 95% confidence intervals (95% CI). There was no association between total, saturated, or monounsaturated fat and distal CRC risk. In African Americans, the OR of distal CRC for the highest category of polyunsaturated fat intake was 0.28 (95% CI = 0.08-0.96). The percent of energy from protein was associated with a 47% risk reduction in Whites (Q4 OR = 0.53, 95% CI = 0.37-0.77). Red meat consumption in Whites was associated with a marginally significant risk reduction (Q4 OR = 0.66, 95% CI = 0.43-1.00). Our results do not support the hypotheses that fat, protein, and red meat increase the risk of distal CRC.

Dietary acculturation and the nutrition transition: an overview

This article provides an overview of the phenomena of "dietary acculturation" and the "nutrition transition". The term dietary acculturation is defined, and a proposed model for how dietary acculturation occurs is presented. Various approaches to assessing dietary acculturation in research studies are discussed, and a research-driven discussion of the possible consequences of dietary acculturation on diet and health is presented. The concept of the nutrition transition and the importance of understanding this phenomenon are presented. Specifically, the term nutrition transition is defined, highlighting characteristic dietary changes, as well as shifts in physical activity and obesity trends. The paradox of continued high rates of malnutrition in developing countries and a new emergence of dietary excess, sedentary behavior, obesity, and other chronic diseases in middle- and upper-class persons in these countries will also be addressed. The article concludes with suggestions for future research in the areas of dietary acculturation and the nutrition transition.

Antioxidant and DNA methylation-related nutrients and risk of distal colorectal cancer

OBJECTIVE

To investigate the relationship between antioxidant nutrients (vitamins C and E, beta-carotene, selenium) and DNA methylation-related nutrients (folate, vitamins B6 and B12) and distal colorectal cancer risk in whites and African Americans and to examine intakes from food only versus total (food plus dietary supplements) intakes.

METHODS

Data are from the North Carolina Colon Cancer Study-Phase II, a case-control study of 945 distal colorectal cancer (including sigmoid, rectosigmoid, and rectum) cases and 959 controls. In-person interviews captured usual dietary intake and various covariates. Multivariate logistic regression was used to calculate odds ratios (OR) and 95% confidence intervals (95% CI).

RESULTS

High intakes of each antioxidant and DNA methylation-related nutrient were significantly associated with lower risk in whites. In African Americans, the highest category of selenium from food only had a marginally significant inverse association with distal colorectal cancer risk (Q4 vs. Q1 OR: 0.55, 95% CI 0.29-1.02). Supplements did not provide additional risk reduction beyond intakes from food.

CONCLUSIONS

Our findings provide evidence that antioxidant and DNA methylation-related nutrients may lower the risk of distal colorectal cancer in whites, and selenium may lower risk in African Americans. Optimal micronutrient intakes from food alone may be more beneficial than supplementation.

Race moderates the relationship between obesity and colorectal cancer screening in women

OBJECTIVE

To determine if the relationship between obesity and usage of colorectal cancer (CRC) screening in women varies when stratifying by race.

METHODS

Using nationally representative data from the 2005 National Health Interview Survey, we examined the relationship between obesity and CRC screening for white and African-American women aged 50 and older. Screening usage variables indicated if a woman was up-to-date for any CRC screening test, colonoscopy, or FOBT. We used multivariable logistic regression models that included interaction terms to determine if race moderates the obesity-screening relationship. We also calculated adjusted up-to-date colonoscopy rates using direct standardization to model covariates.

RESULTS

The relationship between obesity and screening differed by race for any CRC screening test (P = 0.04 for interaction) and for colonoscopy (P = 0.01 for interaction), but not for FOBT. Obese white women had a lower adjusted colonoscopy rate (30.2%, 95% CI 25.9-34.8) than non-obese white women (39.1%, 95% CI 36.1-42.2). Obese African-American women, on the other hand, had a higher adjusted colonoscopy rate (41.2%, 95% CI 31.6-51.4) than their non-obese counterparts (35.6%, 95% CI 28.3-43.6). Overall, adjusted colonoscopy rates were lowest among obese white women.

CONCLUSIONS

Obesity is associated with lower CRC screening rates in white, but not African-American women.

Lung cancer and hormone replacement therapy: association in the vitamins and lifestyle study

PURPOSE

Lung cancer is the leading cause of cancer-related mortality among women. The role of hormone replacement therapy (HRT) in lung cancer development is unclear.

PATIENTS AND METHODS

We evaluated a prospective cohort of 36,588 peri- and postmenopausal women aged 50 to 76 years from Washington State recruited in 2000 to 2002 (Vitamins and Lifestyle [VITAL] Study). Lung cancer cases (n = 344) were identified through the Seattle-Puget Sound Surveillance, Epidemiology, and End Results cancer registry during 6 years of follow-up. Hazard ratios (HRs) associated with use and duration of specific HRT formulations were calculated for total incident lung cancer, specific morphologies, and cancer by stage at diagnosis.

RESULTS

After adjusting for smoking, age, and other potential confounders, there was an increased risk of incident lung cancer associated with increasing duration of estrogen plus progestin (E+P) use (HR = 1.27 for E+P use 1 to 9 years, 95% CI, 0.91 to 1.78; and HR = 1.48 for E+P use > or = 10 years, 95% CI, 1.03 to 2.12; P for trend = .03). There was no association with duration of unopposed estrogen use. Duration of E+P use was associated with an advanced stage at diagnosis (P for trend = .03).

CONCLUSION

Use of E+P increased the risk of incident lung cancer in a duration-dependent manner, with an approximate 50% increased risk for use of 10 years or longer. These findings may be helpful for informing women of their risk of developing lung cancer and delineating important pathways involved in hormone metabolism and lung cancer.

Comparison of three oxidative stress biomarkers in a sample of healthy adults

Oxidative stress is a potentially important aetiological factor for many chronic diseases, including cardiovascular disease, neurodegenerative disease and cancer, yet studies often find inconsistent results. The associations between three of the most widely used biomarkers of oxidative stress, i.e. F(2)-isoprostanes for lipid peroxidation and 8-oxo-7,8-dihydro-2'-deoxyguanosine (8-oxo-dG) and the comet assay with FPG for oxidative DNA damage, were compared in a sample of 135 healthy African-American and white adults. Modest associations were observed between F(2)-isoprostanes and the comet assay (r = 0.22, p = 0.01), but there were no significant correlations between 8-oxo-dG and the comet assay (r = -0.09) or F(2)-IsoP (r = -0.04). These results are informative for researchers seeking to compare results pertaining to oxidative stress across studies and/or assessment methods in healthy disease-free populations. The development and use of oxidative stress biomarkers is a promising field; however, additional validation studies are necessary to establish accuracy and comparability across oxidative stress biomarkers.

Associations between trans fatty acid consumption and colon cancer among Whites and African Americans in the North Carolina colon cancer study I

Disparities in incidence and mortality rates of colon cancer exist between Whites and African Americans. Prior studies examined the association between trans fatty acid consumption and colorectal cancer, but none assessed this possible relationship within a large study population of African Americans and Whites. Using data from a population-based, case-control study in North Carolina, we investigated this association with attention to possible racial differences. Cases and matched controls were queried on demographic characteristics, lifestyle factors, medical history, and diet. Cases reported higher daily consumption (g/day) of trans fatty acids (mean = 5.9, SD = 2.9, median = 5.5, IQR = 3.8-7.5) compared to controls (mean = 5.2, SD = 2.4, median = 4.7, IQR = 3.5-6.4). Energy-adjusted trans fatty acid consumption was not associated with colon cancer. Compared to participants in the lowest quartile of consumption, those in the highest quartile had an adjusted odds ratio of 1.01 (95% confidence interval 0.69, 1.49) for Whites and 0.99 (95% confidence interval 0.61, 1.62) for African Americans. No association was found between increased consumption of trans fatty acid and specific tumor location (proximal or distal colon). In conclusion, trans fatty acid consumption is not associated with colon cancer and does not contribute to disparities in colon cancer rates.

trans-Fatty acid consumption and its association with distal colorectal cancer in the North Carolina Colon Cancer Study II

Recently, the potential health effects of trans-fatty acid consumption have raised concerns. A few studies have examined the risk of colorectal cancer with increasing consumption of trans-fatty acids, but none investigated the risk of rectal cancer, which may have different risk factors than colon cancer. Our objective was to explore the relationship between trans-fatty acid consumption and distal colorectal (sigmoid, rectosigmoid, and rectal) cancer using a case-control study of Whites (n = 1,516) and African Americans (n = 392) in North Carolina from 2001 to 2006. Matched cases and controls were interviewed about demographic information, lifestyle factors, and diet. White cases reported higher mean consumption of trans-fatty acid than White controls, but mean consumption was similar for African American cases and controls. Relative to the lowest quartile, the highest quartiles of energy-adjusted trans-fatty acid consumption were positively associated with distal colorectal cancer for Whites [adjusted ORs for the third and fourth quartiles are 1.54 (95%CI: 1.12, 2.13) and 1.45 (95%CI: 1.04, 2.03), respectively]. Consumption was not associated with distal colorectal cancer in African Americans [adjusted ORs for the third and fourth quartiles are 0.98 (95%CI: 0.47, 2.05) and 0.87 (95%CI 0.42, 1.81), respectively]. In conclusion, high consumption of trans-fatty acids was positively associated with distal colorectal cancer among Whites.

Dietary patterns, food groups, and rectal cancer risk in Whites and African-Americans

BACKGROUND

Associations between individual foods and nutrients and colorectal cancer have been inconsistent, and few studies have examined associations between food, nutrients, dietary patterns, and rectal cancer. We examined the relationship between food groups and dietary patterns and risk for rectal cancer in non-Hispanic Whites and African-Americans.

METHODS

Data were from the North Carolina Colon Cancer Study-Phase II and included 1,520 Whites (720 cases, 800 controls) and 384 African-Americans (225 cases, 159 controls). Diet was assessed using the Diet History Questionnaire. Multivariate logistic regression models were used to estimate odds ratios and 95% confidence intervals.

RESULTS

Among Whites, non-whole grains and white potatoes were associated with elevated risk for rectal cancer whereas fruit, vegetables, dairy, fish, and poultry were associated with reduced risk. In African-Americans, high consumption of other fruit and added sugar suggested elevated risk. We identified three major dietary patterns in Whites and African-Americans. The high fat/meat/potatoes pattern was observed in both race groups but was only positively associated with risk in Whites (odds ratio, 1.84; 95% confidence interval, 1.03-3.15). The vegetable/fish/poultry and fruit/whole grain/dairy patterns in Whites had significant inverse associations with risk. In African-Americans, there was a positive dose-response for the fruit/vegetables pattern (P(trend) < 0.0001) and an inverse linear trend for the legumes/dairy pattern (P(trend) < 0.0001).

CONCLUSION

Our findings indicate that associations of certain food groups and overall dietary patterns with rectal cancer risk differ between Whites and African-Americans, highlighting the importance of examining diet and cancer relationships in racially diverse populations.

Associations of herbal and specialty supplements with lung and colorectal cancer risk in the VITamins and Lifestyle study

Millions of Americans use dietary supplements with little knowledge about their benefits or risks. We examined associations of various herbal/specialty supplements with lung and colorectal cancer risk. Men and women, 50 to 76 years, in the VITamins And Lifestyle cohort completed a 24-page baseline questionnaire that captured duration (years) and frequency (days per week) of use of commonly used herbal/specialty supplements. Dose was not assessed due to the lack of accurate potency information. Supplement exposure was categorized as "no use" or "any use" over the previous 10 years. Hazard ratios (HR) were estimated by multivariate Cox regression models. Incident lung (n = 665) and colorectal cancers (n = 428) were obtained from the Surveillance, Epidemiology, and End Results cancer registry. Any use of glucosamine and chondroitin, which have anti-inflammatory properties, over the previous 10 years, was associated with significantly lower lung cancer risk: HR 0.74 [95% confidence interval (95% CI), 0.58-0.94] and HR 0.72 (95% CI, 0.54-0.96) and colorectal cancer risk: HR 0.73 (95% CI, 0.54-0.98) and HR 0.65 (95% CI, 0.45-0.93), respectively. There were also statistically significantly inverse associations of fish oil: HR 0.65 (95% CI, 0.42-0.99), methylsulfonylmethane: HR 0.46 (95% CI, 0.23-0.93), and St. John's wort: HR 0.35 (95% CI, 0.14-0.85) with colorectal cancer risk. In contrast, garlic pills were associated with a statistically significant 35% elevated colorectal cancer risk. These results suggest that some herbal/specialty supplements may be associated with lung and colorectal cancer risk; however, these products should be used with caution. Additional studies examining the effects of herbal/specialty supplements on risk for cancer and other diseases are needed.

Dietary patterns and colon cancer risk in Whites and African Americans in the North Carolina Colon Cancer Study

We examined associations of dietary patterns with colon cancer risk in African Americans and Whites from a case-control study in North Carolina. Incident colon cancer cases, 40 to 80 yr (n = 636), and matched controls (n = 1,042) were interviewed in person to elicit information on potential colon cancer risk factors. A validated food frequency questionnaire adapted to include regional foods captured diet over the year prior to diagnosis (cases) or interview date (controls). Three meaningful intake patterns were identified in both Whites and African Americans: "Western-Southern," "fruit-vegetable," and "metropolitan." Compared to the Western-Southern pattern, the fruit-vegetable and metropolitan patterns were associated with more healthful dietary behaviors (e.g., higher vegetable intake and lower red meat consumption), and demographic/lifestyle characteristics typically correlated with low colon cancer risk, for example, lower BMI, higher education, and higher NSAID use. The fruit-vegetable pattern was significantly inversely associated with colon cancer risk in Whites (OR = 0.4, 95% CI = 0.3-0.6) and the metropolitan pattern with a nonsignificant 30% risk reduction in both Whites and African Americans after adjustment for education. The Western-Southern pattern was not associated with colon cancer risk. These findings may explain some of the racial differences in colon cancer incidence and underscore the importance of examining diet-cancer associations in different population subgroups.

Selenium, folate, and colon cancer

Selenium is an essential trace element that has been implicated in cancer risk; however, study results have been inconsistent with regard to colon cancer. Our objectives were to 1) investigate the association between selenium and colon cancer, 2) evaluate possible effect measure modifiers, and 3) evaluate potential biases associated with the use of postdiagnostic serum selenium measures. The North Carolina Colon Cancer Study is a large population-based, case-control study of colon cancer in North Carolina between 1996 and 2000 (n = 1,691). Nurses interviewed patients about diet and lifestyle and drew blood specimens, which were used to measure serum selenium. Individuals who had both high serum selenium (> 140 mcg/l) and high reported folate (> 354 mcg/day) had a reduced relative risk of colon cancer [odds ratio (OR) = 0.5, 95% confidence interval (CI) = 0.4-0.8). The risk of colon cancer for those with high selenium and low folate was approximately equal to the risk among those with low selenium and low folate (OR = 1.1, 95% CI = 0.7-1.5) as was the risk for those with low selenium and high folate (OR = 0.9, 95% CI = 0.7-1.2). We did not find evidence of bias due to weight loss, stage at diagnosis, or time from diagnosis to selenium measurement. High levels of serum selenium and reported folate jointly were associated with a substantially reduced risk of colon cancer. Folate status should be taken into account when evaluating the relation between selenium and colon cancer in future studies. Importantly, weight loss, stage at diagnosis, or time from diagnosis to blood draw did not appear to produce strong bias in our study.

Long-term use of beta-carotene, retinol, lycopene, and lutein supplements and lung cancer risk: results from the VITamins And Lifestyle (VITAL) study

High-dose beta-carotene supplementation in high-risk persons has been linked to increased lung cancer risk in clinical trials; whether effects are similar in the general population is unclear. The authors examined associations of supplemental beta-carotene, retinol, vitamin A, lutein, and lycopene with lung cancer risk among participants, aged 50-76 years, in the VITamins And Lifestyle (VITAL) cohort Study in Washington State. In 2000-2002, eligible persons (n = 77,126) completed a 24-page baseline questionnaire, including detailed questions about supplement use (duration, frequency, dose) during the previous 10 years from multivitamins and individual supplements/mixtures. Incident lung cancers (n = 521) through December 2005 were identified by linkage to the Surveillance, Epidemiology, and End Results cancer registry. Longer duration of use of individual beta-carotene, retinol, and lutein supplements (but not total 10-year average dose) was associated with statistically significantly elevated risk of total lung cancer and histologic cell types; for example, hazard ratio = 2.02, 95% confidence interval: 1.28, 3.17 for individual supplemental lutein with total lung cancer and hazard ratio = 3.22, 95% confidence interval: 1.29, 8.07 for individual beta-carotene with small-cell lung cancer for >4 years versus no use. There was little evidence for effect modification by gender or smoking status. Long-term use of individual beta-carotene, retinol, and lutein supplements should not be recommended for lung cancer prevention, particularly among smokers.

Validation of an antioxidant nutrient questionnaire in whites and African Americans

High antioxidant intakes are inversely related to risk for many diseases. However, there is no comprehensive instrument that captures consumption of antioxidant nutrients from both foods and dietary supplements. This report examines the validity of a newly developed questionnaire assessing self-reported dietary and supplemental intakes of antioxidant nutrients (carotenoids, vitamin C, and vitamin E). Between March and December 2005, participants (n=164), 20 to 45 years old, completed the new 92-item antioxidant nutrient questionnaire, a demographic/health questionnaire, four 24-hour dietary recalls, a dietary supplement inventory, and provided semi-fasting blood samples that were analyzed for plasma antioxidant levels. Data analyses included descriptive statistics, correlation coefficients, and linear regression. Mean age of participants was 31.9 years, 51% were African American, and 52% were female. Median antioxidant intakes from the questionnaire and mean of the four recalls were generally comparable. Adjusted Pearson's correlations of questionnaire- and recall-derived intakes ranged from r=0.06 to r=0.56; correlations for the questionnaire and biomarkers ranged from r=0.10 to r=0.33. Agreement rates for classification of intakes from the questionnaire and recalls into the same/adjacent quartiles were 65% to 89%; misclassification to the opposite quartile was rare (range=0 to 12%). For most nutrients, there were linear trends of increasing plasma concentrations with higher questionnaire-derived intakes (P<0.01). Correlations of supplement use between the questionnaire and a supplement inventory were r=0.33 to r=0.84. The new antioxidant nutrient questionnaire demonstrated good validity for collecting self-reported antioxidant nutrient intakes from foods and supplements in both whites and African Americans. The study also underscores the importance of examining the performance characteristics of dietary assessment instruments separately in different population subgroups.

Psychosocial correlates of dietary fat intake in African-American adults: a cross-sectional study

Background

Current dietary guidelines recommend that dietary fat should comprise 20–35% percent of total energy intake, with less than 10% of energy from saturated fat. However, many Americans exceed these goals and data suggest that African Americans tend to consume a higher percentage of energy from dietary fat than Whites. Because diets low in dietary fat, particularly saturated fat, are associated with lower risk for many chronic illnesses, it is important to identify strategies to reduce high fat intakes. This study examined associations of psychosocial factors with dietary fat intake in African American adults 18 to 70 years.

Methods

Data are self-reported from a cross-sectional survey of African Americans (n = 658) using an 11-page questionnaire, collected from June to October 2003. Associations of psychosocial (predisposing, reinforcing, and enabling) factors based on the PRECEDE framework, dietary fat-related behaviors, and participant characteristics (e.g., age, sex, education, BMI) with total and saturated fat consumption are described using linear regression and analysis of variance.

Results

The mean age of participants was 43.9 years, 57% were female, 37% were college graduates, and 76% were overweight/obese. Respondents with lower fat intakes were female, older, had high education and very good/excellent perceived health. Among the psychosocial factors, the strongest (inverse) associations with fat intake were with two predisposing factors: belief in the importance of a low-fat diet (both genders) and high self-efficacy (women only). Fat intake was also significantly lower among participants who could count on those close for encouragement to eat healthy foods (a reinforcing factor) and among men who needed more information about preparing healthy foods (an enabling factor).

Conclusion

Dietary interventions to decrease fat intake in African American adults may benefit from incorporating predisposing factors, such as personal beliefs and self-efficacy, in their design and implementation.

Association of nonsteroidal anti-inflammatory drugs with lung cancer: results from a large cohort study

BACKGROUND

Lung cancer is the most common cause of cancer-related mortality. Smoking cessation is crucial to decrease risk, but additional prevention modalities are needed. The use of nonsteroidal anti-inflammatory drugs (NSAID) may be promising.

METHODS

The study was a prospective cohort of 77,125 men and women, ages 50 to 76 years, from Washington state recruited in 2000 to 2002 (the VITamin And Lifestyle study). Lung cancer cases were identified through the Seattle-Puget Sound Surveillance, Epidemiology and End Results cancer registry during 5 years of follow-up. Hazard ratios (HR) associated with 10-year average use of total NSAIDs (excluding low-dose aspirin) and specific categories of NSAIDs were calculated for total incident lung cancer and specific morphologies.

RESULTS

A total of 665 lung cancer cases were identified. After adjusting for smoking, age, gender, and acetaminophen use, there was a borderline-significant inverse trend with total NSAID use [>4.2 d/wk for >10 years versus none: HR, 0.82; 95% confidence interval (95% CI), 0.64-1.04; P for trend = 0.05]. The association was strongest for adenocarcinoma (HR, 0.59; 95% CI, 0.37-0.94; P for trend = 0.01) and seemed to be limited to men (HR, 0.66; 95% CI, 0.47-0.92; P for trend = 0.01) and to long-term (> or =10 years) former smokers (HR, 0.65; 95% CI, 0.44-0.96; P for trend = 0.04). There were no appreciable differences by NSAID type.

CONCLUSIONS

Total NSAID use was associated with a small reduced risk of lung cancer, which was strongest for adenocarcinoma, men, and long-term former smokers. These findings are supported by known lung carcinogenesis mechanisms and suggest that NSAIDS may be useful for chemoprevention.

Correlates of antioxidant nutrients and oxidative DNA damage differ by race in a cross-sectional study of healthy African American and white adults

Although antioxidant nutrients and oxidative DNA damage have been associated with carcinogenesis, few studies have investigated the factors that influence antioxidant intake and oxidative DNA damage in racially diverse populations. Demographic, behavioral, and diet-related psychosocial correlates of plasma antioxidant (carotenoids, vitamin C, and vitamin E) concentrations and oxidative DNA damage were examined using data from a cross-sectional study of 147 generally healthy, nonsmoking African American and white adults in North Carolina, aged 20 to 45 years. All participants completed self-administered demographic, diet, and health questionnaires and provided semifasting (> or = 6 hours) blood samples. Multivariate regression analyses were computed separately for each race to determine associations between the potential correlates with plasma antioxidant concentrations and oxidative DNA damage, separately. Our findings suggest appreciable differences by race. Only a few factors (age, supplement use, and several psychosocial factors) were associated with antioxidant concentrations in African Americans, whereas these and additional factors, including physical activity, waist circumference, and passive smoke exposure, were associated with antioxidant concentrations in whites. For oxidative DNA damage, passive smoke exposure was significantly associated with oxidative DNA damage in African Americans, and age and alcohol were significant in whites. In addition, the regression models generally explained more of the variance in plasma antioxidant concentrations and oxidative DNA damage in whites than in African Americans. Considering the salient correlates differed by race, this work has important implications for the design and implementation of future research studies investigating antioxidant nutrients and/or oxidative stress, especially those in racially diverse populations.

Use of nonsteroidal antiinflammatory drugs and distal large bowel cancer in whites and African Americans

Despite the belief that the etiology of and risk factors for rectal cancer might differ from those for colon cancer, relatively few studies have examined rectal cancer in relation to use of nonsteroidal antiinflammatory drugs (NSAIDs). The authors evaluated the association between NSAIDs and distal large bowel cancer in African Americans and whites, using data from a population-based case-control study of 1,057 incident cases of adenocarcinoma of the sigmoid colon, rectosigmoid junction, and rectum and 1,019 controls from North Carolina (2001-2006). NSAID use was inversely associated with distal large bowel cancer in whites (odds ratio (OR) = 0.60, 95% confidence interval (CI): 0.46, 0.79). The inverse association was evident for all types of NSAIDs but was slightly stronger with prescription NSAIDs, particularly selective cyclooxygenase 2 inhibitors (OR = 0.38, 95% CI: 0.25, 0.56). Compared with whites, a relatively weak inverse association was found in African Americans (OR = 0.87, 95% CI: 0.55, 1.40), although odds ratio heterogeneity by race could not be confirmed (P = 0.21). In addition, the strength of the association with NSAIDs varied by tumor location, suggesting more potent effects for rectal and rectosigmoid cancers than for sigmoid cancer. The chemopreventive potential of NSAIDs might differ by population and by tumor characteristics.

Consumption of trans-fatty acid and its association with colorectal adenomas

trans-Fatty acid consumption is known to have detrimental effects on cardiovascular health, but little is known about its role in digestive tract neoplasia. To investigate the association between colorectal adenomas and trans-fatty acid consumption, the authors utilized data from a cross-sectional study of 622 individuals who underwent complete colonoscopy between 2001 and 2002 at the University of North Carolina Hospitals. Participants were interviewed about demographic, lifestyle, and dietary factors thought to be related to colorectal cancer. trans-Fatty acid consumption, energy adjusted by the residual method, was categorized into quartiles based on its distribution in controls. Compared with participants in the lowest quartile of consumption, those in the highest quartile had an increased prevalence of colorectal adenomas, with an adjusted prevalence odds ratio of 1.86 (95% confidence interval: 1.04, 3.33). The authors further investigated the relation between trans-fatty acid consumption and colorectal neoplasia by examining the adenoma characteristics, with the adjusted prevalence odds ratios showing little or no difference by adenoma location, size, or number. These results suggest that consumption of high amounts of trans-fatty acid may increase the risk of colorectal neoplasia, and they provide additional support to recommendations to limit trans-fatty acid consumption.

Long-term use of supplemental multivitamins, vitamin C, vitamin E, and folate does not reduce the risk of lung cancer

RATIONALE

Lung cancer is the leading cause of cancer-related mortality in the United States. Although supplements are used by half the population, limited information is available about their specific effect on lung cancer risk.

OBJECTIVES

To explore the association of supplemental multivitamins, vitamin C, vitamin E, and folate with incident lung cancer.

METHODS

Prospective cohort of 77,721 men and women aged 50-76 years from Washington State in the VITAL (VITamins And Lifestyle) study. Cases were identified through the Seattle-Puget Sound SEER (Surveillance, Epidemiology, and End Results) cancer registry.

MEASUREMENTS AND MAIN RESULTS

Hazard ratios (HRs) for incident lung cancer according to 10-year average daily use of supplemental multivitamins, vitamin C, vitamin E, and folate. A total of 521 cases of lung cancer were identified. Adjusting for smoking, age, and sex, there was no inverse association with any supplement. Supplemental vitamin E was associated with a small increased risk of lung cancer (HR, 1.05 for every 100-mg/d increase in dose; 95% confidence interval [CI], 1.00-1.09; P = 0.033). This risk of supplemental vitamin E was largely confined to current smokers (HR, 1.11 for every 100-mg/d increase; 95% CI, 1.03-1.19; P < 0.01) and was greatest for non-small cell lung cancer (HR, 1.07 for every 100-mg/d increase; 95% CI, 1.02-1.12; P = 0.004).

CONCLUSIONS

Supplemental multivitamins, vitamin C, vitamin E, and folate were not associated with a decreased risk of lung cancer. Supplemental vitamin E was associated with a small increased risk. Patients should be counseled against using these supplements to prevent lung cancer.

Intrinsic and extrinsic motivations for healthful dietary change in African Americans

OBJECTIVE

To describe associations of intrinsic and extrinsic motivations for dietary change with participant characteristics and current diet among African Americans.

METHODS

Cross-sectional survey of 658 African American adults in North Carolina provided information on intrinsic (self-image and health concerns) and extrinsic (social influence) motivation scales, participant characteristics, and diet.

RESULTS

Most respondents considered it important to change their diet for health reasons; fewer were motivated by self-image or social influence. Motivation scales were significantly associated with demographic, behavioral, and psychosocial characteristics and fat, but not fruit/vegetable consumption, after adjustment for covariates (P<0.05).

CONCLUSION

Tailoring on intrinsic and extrinsic motives may improve the effectiveness of dietary interventions in African Americans.

Demographic, behavioral, psychosocial, and dietary correlates of cancer screening in African Americans

PURPOSE

We examined demographic, behavioral, psychosocial, and dietary correlates of prostate, breast, and colorectal cancer screening in a population-based sample of African Americans in North Carolina (n=405).

METHODS

Cross-sectional data of African Americans in North Carolina were analyzed using linear regression models.

RESULTS

Seventy-eight percent of men had obtained prostate screening (PSA test) and 81% of women had received breast cancer screening (mammogram) during the previous two years. Screening rates for CRC were lower (48% women, 31% men in the previous ten years). Older age, college education, and being married were associated with all screening modalities, as was belief in a diet-cancer relationship with PSA testing and mammography. There were correlations of former smoking, obesity, and healthy eating self-efficacy with PSA testing, and family/personal cancer history with CRC screening. Screening for all cancers was associated with lower fat consumption, and PSA testing with high fruit/vegetable intake (p<.05).

CONCLUSIONS

Cancer screening was prevalent, but rates did not approach national targets. Knowledge of these correlates can be used to design effective cancer screening interventions for African Americans.

Circulating levels of inflammatory cytokines and risk of colorectal adenomas

The association between obesity and colorectal neoplasia may be mediated by inflammation. Circulating levels of C-reactive protein (CRP), interleukin-6 (IL-6), and tumor necrosis factor-alpha (TNF-alpha) are elevated in the obese. Adipose tissue can produce and release the inflammatory cytokines that are potentially procarcinogenic. We examined circulating levels of CRP, IL-6, and TNF-alpha in relation to risk factors and the prevalence of colorectal adenomas. Plasma levels of CRP, IL-6, and TNF-alpha were quantified in 873 participants (242 colorectal adenoma cases and 631 controls) in a colonoscopy-based cross-sectional study conducted between 1998 and 2002. Multivariable logistic regression was used to estimate associations between known risk factors for colorectal neoplasia and circulating levels of inflammatory cytokines and associations between inflammatory cytokines and colorectal adenomas. Several known risk factors for colorectal neoplasia were associated with higher levels of inflammatory cytokines, including older age, current smoking, and increasing adiposity. The prevalence of colorectal adenomas was associated with higher concentrations of IL-6 and TNF-alpha and, to a lesser degree, with CRP. For IL-6, adjusted odds ratios (OR) for colorectal adenomas were 1.79 [95% confidence interval (CI), 1.19-2.69] for the second highest plasma level and 1.85 (95% CI, 1.24-2.75) for the highest level compared with the reference level. A similar association was found with TNF-alpha, with adjusted ORs of 1.56 (95% CI, 1.03-2.36) and 1.66 (95% CI, 1.10-2.52), respectively. Our findings indicate that systemic inflammation might be involved in the early development of colorectal neoplasia.

Correlates of toenail zinc in a free-living U.S. population

OBJECTIVE

No prior studies have reported on dietary correlates of toenail zinc, an easily collected biomarker of zinc status. The study aim was to identify dietary and other factors that influence toenail zinc in a healthy population, in order to understand the usefulness of this biomarker in public health studies.

DESIGN

Cross-sectional comparison of toenail zinc with questionnaire measures of demographic and behavioral factors, dietary intake and supplement use.

SETTING

Western Washington State, US.

SUBJECTS

106 men and 106 women, who are participants in a large cohort study, of whom 66% used multivitamins or individual supplements containing zinc.

RESULTS

Increased toenail zinc concentrations were associated with increased dietary zinc intake (adjusted difference in toenail zinc between those in the highest quartile of intake vs. lowest = 11.0 ppm, p for trend = 0.03), with the association primarily among men. Borderline associations of increased toenail zinc were found with decreased vegetable intake (p=0.08) and increased body mass index (p=0.11). Supplemental zinc and intake of phytic acid, alcohol, iron (from food or supplements) did not influence toenail zinc.

CONCLUSION

Toenail zinc concentrations vary with dietary zinc intake, even in a healthy population with presumably little zinc deficiency.

Poverty, obesity, and malnutrition: an international perspective recognizing the paradox

In the year 2000, multiple global health agencies and stakeholders convened and established eight tenets that, if followed, would make our world a vastly better place. These tenets are called the Millennium Development Goals. Most of these goals are either directly or indirectly related to nutrition. The United Nations has led an evaluation team to monitor and assess the progress toward achieving these goals until 2015. We are midway between when the goals were set and the year 2015. The first goal is to "eradicate extreme poverty and hunger." Our greatest responsibility as nutrition professionals is to understand the ramifications of poverty, chronic hunger, and food insecurity. Food insecurity is complex, and the paradox is that not only can it lead to undernutrition and recurring hunger, but also to overnutrition, which can lead to overweight and obesity. It is estimated that by the year 2015 noncommunicable diseases associated with overnutrition will surpass undernutrition as the leading causes of death in low-income communities. Therefore, we need to take heed of the double burden of malnutrition caused by poverty, hunger, and food insecurity. Informing current practitioners, educators, and policymakers and passing this information on to future generations of nutrition students is of paramount importance.

Measurement error adjustment in essential fatty acid intake from a food frequency questionnaire: alternative approaches and methods

Background

We aimed at assessing the degree of measurement error in essential fatty acid intakes from a food frequency questionnaire and the impact of correcting for such an error on precision and bias of odds ratios in logistic models. To assess these impacts, and for illustrative purposes, alternative approaches and methods were used with the binary outcome of cognitive decline in verbal fluency.

Methods

Using the Atherosclerosis Risk in Communities (ARIC) study, we conducted a sensitivity analysis. The error-prone exposure – visit 1 fatty acid intake (1987–89) – was available for 7,814 subjects 50 years or older at baseline with complete data on cognitive decline between visits 2 (1990–92) and 4 (1996–98). Our binary outcome of interest was clinically significant decline in verbal fluency. Point estimates and 95% confidence intervals were compared between naïve and measurement-error adjusted odds ratios of decline with every SD increase in fatty acid intake as % of energy. Two approaches were explored for adjustment: (A) External validation against biomarkers (plasma fatty acids in cholesteryl esters and phospholipids) and (B) Internal repeat measurements at visits 2 and 3. The main difference between the two is that Approach B makes a stronger assumption regarding lack of error correlations in the structural model. Additionally, we compared results from regression calibration (RCAL) to those from simulation extrapolation (SIMEX). Finally, using structural equations modeling, we estimated attenuation factors associated with each dietary exposure to assess degree of measurement error in a bivariate scenario for regression calibration of logistic regression model.

Results and conclusion

Attenuation factors for Approach A were smaller than B, suggesting a larger amount of measurement error in the dietary exposure. Replicate measures (Approach B) unlike concentration biomarkers (Approach A) may lead to imprecise odds ratios due to larger standard errors. Using SIMEX rather than RCAL models tends to preserve precision of odds ratios. We found in many cases that bias in naïve odds ratios was towards the null. RCAL tended to correct for a larger amount of effect bias than SIMEX, particularly for Approach A.

Associations of Antioxidant Nutrients and Oxidative DNA Damage in Healthy African-American and White Adults

High antioxidant intake has been shown to reduce cancer risk and may also mitigate the effects of oxidative DNA damage, which is hypothesized to be causally linked to carcinogenesis. This study examined potential racial differences in (a) dietary intakes and plasma concentrations of vitamin C, vitamin E, and carotenoids and oxidative DNA damage and (b) associations between plasma antioxidants and oxidative DNA damage. Data were from a cross-sectional study of 164 generally healthy nonsmoking African-Americans and Whites in North Carolina, ages 20 to 45 years, equally distributed by race and sex. Participants completed a demographic and health questionnaire, four 24-h dietary recalls, and a dietary supplement inventory; had height and weight measured; and provided a semifasting blood sample. African-Americans had statistically significantly lower plasma concentrations of vitamin E, alpha-carotene, beta-carotene, and lutein + zeaxanthin than Whites, as well as lower self-reported intake of most antioxidants. Levels of oxidative DNA damage, measured using the alkaline comet assay, were lower in African-Americans than Whites. An inverse association between lycopene and oxidative DNA damage (r = -0.20; P = 0.03) was found in the combined study population after adjusting for sex, age, body mass index, passive smoke exposure, physical activity, education, income, and alcohol intake. There was also a positive association of vitamin E with oxidative DNA damage in the total population (r = 0.21; P = 0.02) and in African-American men (r = 0.63; P = 0.01) after adjusting for covariates. This study is among the first to examine these associations in a sample of healthy adults with an adequate representation of African-Americans.

Plasma n-3 fatty acids and the risk of cognitive decline in older adults: the Atherosclerosis Risk in Communities Study

BACKGROUND

Plasma fatty acids may affect the risk of cognitive decline in older adults.

OBJECTIVES

We prospectively studied the association between plasma fatty acids and cognitive decline in adults aged 50-65 y at baseline and conducted a subgroup analysis.

DESIGN

From 1987 through 1989, the Atherosclerosis Risk in Communities (ARIC) Study analyzed plasma fatty acids in cholesteryl esters and phospholipids in whites residing in Minneapolis, MN. From 1990 through 1992 and from 1996 through 1998, 3 neuropsychological tests in the domains of delayed word recall, psychomotor speed, and verbal fluency were administered. We selected cutoffs for statistically reliable cognitive decline in each of these domains and a measure of global cognitive change computed by principal-components analysis. Multivariate logistic regression was conducted. Focusing on n-3 highly unsaturated fatty acids (HUFAs), a subgroup analysis assessed differential association across potential effect modifiers implicated in oxidative stress and increased risk of neurodegenerative disease.

RESULTS

In the 2251 study subjects, the risk of global cognitive decline increased with elevated palmitic acid in both fractions and with high arachidonic acid and low linoleic acid in cholesteryl esters. Higher n-3 HUFAs reduced the risk of decline in verbal fluency, particularly in hypertensive and dyslipidemic subjects. No significant findings were shown for psychomotor speed or delayed word recall.

CONCLUSIONS

Promoting higher intakes of n-3 HUFAs in the diet of hypertensive and dyslipidemic persons may have substantial benefits in reducing their risk of cognitive decline in the area of verbal fluency. However, clinical trials are needed to confirm this finding.

A diet high in fruits and low in meats reduces the risk of colorectal adenomas

Recent evidence suggests overall dietary patterns, rather than specific dietary components, may be a better predictor of colorectal adenomas or cancers. Using cluster analysis, we aimed to assess the association between dietary patterns and colorectal adenomas and whether adjusting for total energy consumption prior to creating clusters affects this relation. Data from a case-control study of 725 individuals undergoing a colonoscopy were utilized. Cases (n = 203) had > or =1 adenoma on colonoscopy, and controls (n = 522) were those who had no adenomas. Dietary data were obtained from an FFQ. Daily intake for 18 different food groups was calculated. The values were transformed into Z-scores. Participants were first clustered without energy adjustment, then again based on their consumption per 1000 kcal (4187 kJ). There was no association between dietary patterns and colorectal adenomas without energy adjustment prior to creating dietary clusters, as clusters formed as a by-product of energy consumption. After adjusting for energy consumption, 3 distinct clusters emerged: 1) high fruit-low meat cluster; 2) high vegetable-moderate meat cluster; and 3) high meat cluster. After adjusting for potential confounders, the high vegetable-moderate meat cluster (odds ratio [OR] 2.17: [95% CI] 1.20-3.90) and high meat cluster (OR 1.70: [95% CI] 1.04-2.80) were at significantly increased odds of having had an adenoma compared with the high fruit-low meat cluster. A high-fruit, low-meat diet appears to be protective against colorectal adenomas compared with a dietary pattern of increased vegetable and meat consumption.

Calcium, dietary, and lifestyle factors in the prevention of colorectal adenomas

BACKGROUND

Many studies have suggested a role for calcium in reducing the risk of colorectal adenomas and cancer but its effectiveness may be dependent on interactions with other dietary and/or lifestyle factors. We examined the association between calcium and prevalence of adenomas and assessed whether the association was stronger in biologically plausible subgroups.

METHODS

Cross-sectional data from 222 cases and 479 adenoma-free controls who underwent colonoscopies and completed food frequency and lifestyle questionnaires were used in the analyses. Multivariable logistic regression was used to estimate the association between calcium and prevalence of adenomas. Stratified analyses and the likelihood ratio test were used to examine effect modification by various demographic, lifestyle, and behavioral factors.

RESULTS

Overall, little association was observed comparing total calcium intake of > or = 900 mg/day to < 500 mg/day (adjusted odds ratio [OR] = 0.85, 95% confidence interval [CI]: 0.53-1.37). However, stronger associations were observed in patients with lower fat intake and in those who regularly (> or = 15 times/month) took nonsteroidal antiinflammatory drugs (NSAIDs). Specifically, total calcium intake of > or = 900 mg/day was associated with a lower prevalence of adenomas among patients with lower fat intake (OR = 0.47, 95% CI: 0.25-0.91) but not among those with higher fat intake (OR = 1.20, 95% CI: 0.61-2.35; P-value for interaction = .01). For NSAIDs, the associations were OR = 0.37 (95% CI: 0.16-0.86) for regular NSAID users and OR = 1.27 (95% CI: 0.73-2.22) with infrequent or nonuse of NSAIDs, respectively (P = .06).

CONCLUSIONS

The data suggest that a lower-fat diet and regular NSAID use may enhance calcium's effectiveness as a colorectal cancer preventive agent.

Associations of psychosocial factors with fruit and vegetable intake among African-Americans

OBJECTIVE

To examine associations of various psychosocial factors with fruit and vegetable intake in African-American adults.

METHODS

A cross-sectional survey of a population-based sample of 658 African-Americans, aged 18-70 years, in North Carolina. Information was collected on diet-related psychosocial (predisposing, reinforcing and enabling) factors based on the PRECEDE (Predisposing, Reinforcing, and Enabling Constructs in Educational Diagnosis and Evaluation) planning framework; demographic, lifestyle and behavioural characteristics, and fruit and vegetable intake.

RESULTS

The mean participant age was 43.9 years (standard deviation 11.6), 57% were female and 76% were overweight/obese. Participants expressed healthy beliefs regarding many of, but not all, the psychosocial factors. For example, although half of the respondents believed it is important to eat a diet high in fruits/vegetables, only 26% knew that >or=5 daily servings are recommended. The strongest associations of the psychosocial factors with fruit/vegetable intake were for predisposing factors (e.g. belief in the importance of a high fruit/vegetable diet and knowledge of fruit/vegetable recommendations) and one reinforcing factor (social support), with differences between the healthiest and least healthy responses of 0.5-1.0 servings per day. There was evidence of effect modification by gender in associations between psychosocial factors and fruit/vegetable consumption (e.g. self-efficacy was only significant in women), with higher intakes and generally healthier responses to the psychosocial variables in women than men.

CONCLUSIONS

Interventions to increase fruit/vegetable intake in African-Americans may be more effective if they focus primarily on predisposing factors, such as knowledge, self-efficacy and attitudes, but not to the exclusion of reinforcing and enabling factors. The psychosocial factors that are targeted may also need to be somewhat different for African-American men and women.

Reliability and validity of 2 single-item measures of psychosocial stress

BACKGROUND

Practical limitations in epidemiologic research may necessitate use of only a few questions for assessing the complex phenomenon called "stress." The objective of this study was to evaluate the measurement characteristics of 2 single-item measures on the amount of stress and the ability to handle stress.

METHODS

We selected 218 adults age 50 to 76 years living in western Washington state from a large prospective cohort study of lifestyle factors and cancer risk to evaluate the 3-month test-retest reliability and intermethod reliability of the stress questions. To assess the latter, we compared 2 single-item measures on stress with 3 more fully validated multi-item instruments on perceived stress, daily hassles, and life events, which assessed the same underlying constructs as the single-item measures.

RESULTS

The test-retest reliabilities for the single-item stress measures were good (kappa and intraclass correlations between 0.66 and 0.74). The intermethod reliabilities comparing the 2 single-item stress measures with 3 multi-item instruments were moderate (r = 0.31-0.46) and comparable to correlations observed among the 3 multi-item instruments (r = 0.25-0.47).

CONCLUSIONS

The 2 single-item stress measures are reliable at measuring stress with validity similar to longer questionnaires. Single-item measures offer a practical instrument for assessing stress in large prospective epidemiologic studies that lack space for longer instruments.

Epidemiology of systemic lupus erythematosus: a comparison of worldwide disease burden

Systemic lupus erythematosus (SLE) is a disease of multifactorial etiology. Quantifying the burden of SLE across different countries can clarify the role of genetic, environmental and other causative factors in the natural history of the disease, and to understand its clinical and societal consequences. The aim of this study is to summarize data on SLE incidence and prevalence in the USA, Europe, Asia, and Australia. An extensive review of electronic resources (PubMed and MedLine) and medical journals was conducted to identify published studies on SLE incidence and prevalence over the period of 1950-early 2006. Researchers in the countries of interest provided additional information on the epidemiology of SLE. The incidence and prevalence of SLE varies considerably across the countries. The burden of the disease is considerably elevated among non-white racial groups. There is a trend towards higher incidence and prevalence of SLE in Europe and Australia compared to the U.S.A. In Europe, the highest prevalence was reported in Sweden, Iceland and Spain. There are marked disparities in SLE rates worldwide. This variability may reflect true differences across populations, or result from methodological differences of studies. The true geographic, racial, and temporal differences in SLE incidence and prevalence may yield important clues to the etiology of disease.

Selenium, apoptosis, and colorectal adenomas

BACKGROUND

Selenium is an essential trace element found in cereals, wheat, dairy products, meat, and fish. This micronutrient may prevent carcinogenesis through several biochemical pathways; one suggested pathway is enhanced apoptosis.

OBJECTIVES

The relation between selenium and colorectal adenomas was evaluated because the colorectal adenoma is the established precursor lesion of most colorectal cancers. Apoptosis was a pathway of interest because decreased apoptosis has been associated with an increased prevalence of adenomas. Our objectives were as follows: to investigate the association between (a) selenium and colorectal adenomas and (b) selenium and apoptosis.

METHODS

The study population was assembled for the Diet and Health Study III (n = 803), a cross-sectional study conducted at the University of North Carolina Hospital (Chapel Hill, NC). There were 451 participants in the analysis of selenium and adenoma prevalence and 351 participants in the analysis of selenium and apoptosis. Selenium was measured from serum collected at the time of colonoscopy. Apoptosis was measured in biopsies from normal rectal epithelium obtained during the colonoscopy procedure.

RESULTS

Participants in the highest fifth of serum selenium were less likely to have adenomas in comparison with those in the lowest fifth (prevalence ratio, 0.6; 95% confidence interval, 0.4-1.1). Selenium and apoptosis (>2.76 cells per crypt) were not strongly related, but results collectively suggested a roughly inverse association.

CONCLUSIONS

High selenium was associated with a reduced prevalence of colorectal adenomas. Apoptosis, however, did not seem to be the mechanism by which selenium was related to adenoma prevalence in our data.

Epidemiology of systemic lupus erythematosus: a comparison of worldwide disease burden

Systemic lupus erythematosus (SLE) is a disease of multifactorial etiology. Quantifying the burden of SLE across different countries can clarify the role of genetic, environmental and other causative factors in the natural history of the disease, and to understand its clinical and societal consequences. The aim of this study is to summarize data on SLE incidence and prevalence in the USA, Europe, Asia, and Australia. An extensive review of electronic resources (PubMed and MedLine) and medical journals was conducted to identify published studies on SLE incidence and prevalence over the period of 1950-early 2006. Researchers in the countries of interest provided additional information on the epidemiology of SLE. The incidence and prevalence of SLE varies considerably across the countries. The burden of the disease is considerably elevated among non-white racial groups. There is a trend towards higher incidence and prevalence of SLE in Europe and Australia compared to the USA. In Europe, the highest prevalence was reported in Sweden, Iceland and Spain. There are marked disparities in SLE rates worldwide. This variability may reflect true differences across populations, or result from methodological differences of studies. The true geographic, racial, and temporal differences in SLE incidence and prevalence may yield important clues to the etiology of disease.

Epidemiology of systemic lupus erythematosus: a comparison of worldwide disease burden

Systemic lupus erythematosus (SLE) is a disease of multifactorial etiology. Quantifying the burden of SLE across different countries can clarify the role of genetic, environmental and other causative factors in the natural history of the disease, and to understand its clinical and societal consequences. The aim of this study is to summarize data on SLE incidence and prevalence in the USA, Europe, Asia, and Australia. An extensive review of electronic resources (PubMed and MedLine) and medical journals was conducted to identify published studies on SLE incidence and prevalence over the period of 1950-early 2006. Researchers in the countries of interest provided additional information on the epidemiology of SLE. The incidence and prevalence of SLE varies considerably across the countries. The burden of the disease is considerably elevated among non-white racial groups. There is a trend towards higher incidence and prevalence of SLE in Europe and Australia compared to the USA. In Europe, the highest prevalence was reported in Sweden, Iceland and Spain. There are marked disparities in SLE rates worldwide. This variability may reflect true differences across populations, or result from methodological differences of studies. The true geographic, racial, and temporal differences in SLE incidence and prevalence may yield important clues to the etiology of disease.

Epidemiology of systemic lupus erythematosus: a comparison of worldwide disease burden

Systemic lupus erythematosus (SLE) is a disease of multifactorial etiology. Quantifying the burden of SLE across different countries can clarify the role of genetic, environmental and other causative factors in the natural history of the disease, and to understand its clinical and societal consequences. The aim of this study is to summarize data on SLE incidence and prevalence in the USA, Europe, Asia, and Australia. An extensive review of electronic resources (PubMed and MedLine) and medical journals was conducted to identify published studies on SLE incidence and prevalence over the period of 1950-early 2006. Researchers in the countries of interest provided additional information on the epidemiology of SLE. The incidence and prevalence of SLE varies considerably across the countries. The burden of the disease is considerably elevated among non-white racial groups. There is a trend towards higher incidence and prevalence of SLE in Europe and Australia compared to the USA. In Europe, the highest prevalence was reported in Sweden, Iceland and Spain. There are marked disparities in SLE rates worldwide. This variability may reflect true differences across populations, or result from methodological differences of studies. The true geographic, racial, and temporal differences in SLE incidence and prevalence may yield important clues to the etiology of disease.

Epidemiology of systemic lupus erythematosus: a comparison of worldwide disease burden

Systemic lupus erythematosus (SLE) is a disease of multifactorial etiology. Quantifying the burden of SLE across different countries can clarify the role of genetic, environmental and other causative factors in the natural history of the disease, and to understand its clinical and societal consequences. The aim of this study is to summarize data on SLE incidence and prevalence in the USA, Europe, Asia, and Australia. An extensive review of electronic resources (PubMed and MedLine) and medical journals was conducted to identify published studies on SLE incidence and prevalence over the period of 1950-early 2006. Researchers in the countries of interest provided additional information on the epidemiology of SLE. The incidence and prevalence of SLE varies considerably across the countries. The burden of the disease is considerably elevated among non-white racial groups. There is a trend towards higher incidence and prevalence of SLE in Europe and Australia compared to the USA. In Europe, the highest prevalence was reported in Sweden, Iceland and Spain. There are marked disparities in SLE rates worldwide. This variability may reflect true differences across populations, or result from methodological differences of studies. The true geographic, racial, and temporal differences in SLE incidence and prevalence may yield important clues to the etiology of disease.

Epidemiology of systemic lupus erythematosus: a comparison of worldwide disease burden

Systemic lupus erythematosus (SLE) is a disease of multifactorial etiology. Quantifying the burden of SLE across different countries can clarify the role of genetic, environmental and other causative factors in the natural history of the disease, and to understand its clinical and societal consequences. The aim of this study is to summarize data on SLE incidence and prevalence in the USA, Europe, Asia, and Australia. An extensive review of electronic resources (PubMed and MedLine) and medical journals was conducted to identify published studies on SLE incidence and prevalence over the period of 1950-early 2006. Researchers in the countries of interest provided additional information on the epidemiology of SLE. The incidence and prevalence of SLE varies considerably across the countries. The burden of the disease is considerably elevated among non-white racial groups. There is a trend towards higher incidence and prevalence of SLE in Europe and Australia compared to the USA. In Europe, the highest prevalence was reported in Sweden, Iceland and Spain. There are marked disparities in SLE rates worldwide. This variability may reflect true differences across populations, or result from methodological differences of studies. The true geographic, racial, and temporal differences in SLE incidence and prevalence may yield important clues to the etiology of disease.

Epidemiology of systemic lupus erythematosus: a comparison of worldwide disease burden

Systemic lupus erythematosus (SLE) is a disease of multifactorial etiology. Quantifying the burden of SLE across different countries can clarify the role of genetic, environmental and other causative factors in the natural history of the disease, and to understand its clinical and societal consequences. The aim of this study is to summarize data on SLE incidence and prevalence in the USA, Europe, Asia, and Australia. An extensive review of electronic resources (PubMed and MedLine) and medical journals was conducted to identify published studies on SLE incidence and prevalence over the period of 1950-early 2006. Researchers in the countries of interest provided additional information on the epidemiology of SLE. The incidence and prevalence of SLE varies considerably across the countries. The burden of the disease is considerably elevated among non-white racial groups. There is a trend towards higher incidence and prevalence of SLE in Europe and Australia compared to the USA. In Europe, the highest prevalence was reported in Sweden, Iceland and Spain. There are marked disparities in SLE rates worldwide. This variability may reflect true differences across populations, or result from methodological differences of studies. The true geographic, racial, and temporal differences in SLE incidence and prevalence may yield important clues to the etiology of disease.

Epidemiology of systemic lupus erythematosus: a comparison of worldwide disease burden

Systemic lupus erythematosus (SLE) is a disease of multifactorial etiology. Quantifying the burden of SLE across different countries can clarify the role of genetic, environmental and other causative factors in the natural history of the disease, and to understand its clinical and societal consequences. The aim of this study is to summarize data on SLE incidence and prevalence in the USA, Europe, Asia, and Australia. An extensive review of electronic resources (PubMed and MedLine) and medical journals was conducted to identify published studies on SLE incidence and prevalence over the period of 1950-early 2006. Researchers in the countries of interest provided additional information on the epidemiology of SLE. The incidence and prevalence of SLE varies considerably across the countries. The burden of the disease is considerably elevated among non-white racial groups. There is a trend towards higher incidence and prevalence of SLE in Europe and Australia compared to the USA. In Europe, the highest prevalence was reported in Sweden, Iceland and Spain. There are marked disparities in SLE rates worldwide. This variability may reflect true differences across populations, or result from methodological differences of studies. The true geographic, racial, and temporal differences in SLE incidence and prevalence may yield important clues to the etiology of disease.

Epidemiology of systemic lupus erythematosus: a comparison of worldwide disease burden

Systemic lupus erythematosus (SLE) is a disease of multifactorial etiology. Quantifying the burden of SLE across different countries can clarify the role of genetic, environmental and other causative factors in the natural history of the disease, and to understand its clinical and societal consequences. The aim of this study is to summarize data on SLE incidence and prevalence in the USA, Europe, Asia, and Australia. An extensive review of electronic resources (PubMed and MedLine) and medical journals was conducted to identify published studies on SLE incidence and prevalence over the period of 1950-early 2006. Researchers in the countries of interest provided additional information on the epidemiology of SLE. The incidence and prevalence of SLE varies considerably across the countries. The burden of the disease is considerably elevated among non-white racial groups. There is a trend towards higher incidence and prevalence of SLE in Europe and Australia compared to the USA. In Europe, the highest prevalence was reported in Sweden, Iceland and Spain. There are marked disparities in SLE rates worldwide. This variability may reflect true differences across populations, or result from methodological differences of studies. The true geographic, racial, and temporal differences in SLE incidence and prevalence may yield important clues to the etiology of disease.

Epidemiology of systemic lupus erythematosus: a comparison of worldwide disease burden

Systemic lupus erythematosus (SLE) is a disease of multifactorial etiology. Quantifying the burden of SLE across different countries can clarify the role of genetic, environmental and other causative factors in the natural history of the disease, and to understand its clinical and societal consequences. The aim of this study is to summarize data on SLE incidence and prevalence in the USA, Europe, Asia, and Australia. An extensive review of electronic resources (PubMed and MedLine) and medical journals was conducted to identify published studies on SLE incidence and prevalence over the period of 1950-early 2006. Researchers in the countries of interest provided additional information on the epidemiology of SLE. The incidence and prevalence of SLE varies considerably across the countries. The burden of the disease is considerably elevated among non-white racial groups. There is a trend towards higher incidence and prevalence of SLE in Europe and Australia compared to the USA. In Europe, the highest prevalence was reported in Sweden, Iceland and Spain. There are marked disparities in SLE rates worldwide. This variability may reflect true differences across populations, or result from methodological differences of studies. The true geographic, racial, and temporal differences in SLE incidence and prevalence may yield important clues to the etiology of disease.

Epidemiology of systemic lupus erythematosus: a comparison of worldwide disease burden

Systemic lupus erythematosus (SLE) is a disease of multifactorial etiology. Quantifying the burden of SLE across different countries can clarify the role of genetic, environmental and other causative factors in the natural history of the disease, and to understand its clinical and societal consequences. The aim of this study is to summarize data on SLE incidence and prevalence in the USA, Europe, Asia, and Australia. An extensive review of electronic resources (PubMed and MedLine) and medical journals was conducted to identify published studies on SLE incidence and prevalence over the period of 1950-early 2006. Researchers in the countries of interest provided additional information on the epidemiology of SLE. The incidence and prevalence of SLE varies considerably across the countries. The burden of the disease is considerably elevated among non-white racial groups. There is a trend towards higher incidence and prevalence of SLE in Europe and Australia compared to the USA. In Europe, the highest prevalence was reported in Sweden, Iceland and Spain. There are marked disparities in SLE rates worldwide. This variability may reflect true differences across populations, or result from methodological differences of studies. The true geographic, racial, and temporal differences in SLE incidence and prevalence may yield important clues to the etiology of disease.