P-value For Linear Trend Research Articles

Association of endogenous sex hormone with C‐reactive protein levels in middle‐aged and elderly men

In women, postmenopausal oestrogen supplementation increases levels of systemic markers of inflammation, which are important predictors of coronary heart disease (CHD) risk. Whether endogenous sex hormone levels in men are also related to systemic subclinical inflammation is still unknown. We tested the hypothesis that higher endogenous sex hormones levels within the physiological range may be associated with systemic subclinical inflammation. Circulating sex hormone and high-sensitivity C-reactive protein (hs-CRP) levels were determined in 400 apparently healthy men aged between 40 and 80 years. We used multivariate linear regression analysis with the various sex hormones as determinant, and natural log hs-CRP as outcome. Higher levels of total as well as bioavailable oestradiol (E2) were associated with increased natural log hs-CRP levels, which remained statistically significant after adjustment for age and cardiovascular risk factors. Natural log hs-CRP was 0.26 mg/l higher [95% confidence interval (CI) -0.02 to 0.54] in the fourth than in the first quartile of total E2; the P-value for linear trend was 0.05. For bioavailable E2, the difference in natural log hs-CRP between the fourth and the first quartile was 0.30 mg/l (95% CI 0.03-0.56; P-value for linear trend 0.04). After adjustment for age and cardiovascular risk factors, physiological levels of total (TT) or bioavailable testosterone or dehydroepiandrosterone sulfate (DHEAS) were not associated with hs-CRP. Endogenous total and bioavailable E2 levels are significantly associated with CRP among middle-aged and elder men.

Nutritional predictors for cellular nipple aspirate fluid: Nutrition and Breast Health Study

The presence of epithelial cells in breast nipple aspirate fluid (NAF), irrespective of abnormality, has been associated with increased risk of breast cancer in previous studies. We sought to investigate whether the presence of epithelial cells in NAF is associated with nutritional parameters among 71 healthy premenopausal women who participated in the Nutrition and Breast Health Study and provided any samples of NAF during the study. Total of 142 samples which were obtained over a 1-year period of intervention with low-fat and/or high vegetable-fruit diets were available for cytological evaluation. The odds ratios (ORs) and 95% confidence intervals (CIs) for the detection of epithelial cells in NAF were estimated by fitting generalized estimating equations models by quartile level of nutritional parameters. The probability of yielding epithelial cell-positive NAF progressively increased with increasing total fat intake (p=0.001). The OR for the highest quartile level of fat intake, compared with lowest, was 7.22 (95% CI 1.14-45.82). On the other hand, there were a marginally significant inverse association with total fiber intake as well as an weak inverse association with the number of servings of fruit and vegetables. Furthermore, the probability of detecting epithelial cells in NAF decreased with increasing plasma levels of lutein and alpha-carotene (p-values for linear trend; 0.001 and 0.049, respectively). The ORs for the highest versus lowest quartile levels are 0.17 (95% CI 0.04-0.65) and 0.19 (95% CI 0.04-0.91), respectively. These results are generally in support of roles of nutritional factors in breast cancer and thus further studies are warranted.

Total and specific fluid consumption as determinants of bladder cancer risk

We pooled the data from 6 case-control studies of bladder cancer with detailed information on fluid intake and water pollutants, particularly trihalomethanes (THM), and evaluated the bladder cancer risk associated with total and specific fluid consumption. The analysis included 2,729 cases and 5,150 controls. Odds ratios (OR) and 95% confidence intervals (CI) for fluid consumption were adjusted for age, gender, study, smoking status, occupation and education. Total fluid intake was associated with an increased risk of bladder cancer in men. The adjusted OR for 1 l/day increase in intake was 1.08, (95% CI 1.03-1.14, p-value for linear trend <0.001), while no trend was observed in women (OR=1.04, 0.94-1.15; p-value=0.7). OR was 1.33 (1.12-1.58) for men in the highest category of intake (>3.5 l/day) as compared to those in the lowest (<or=2 l/day). An increased risk was associated with intake of tap water. OR for >2 l/day vs. <or=0.5 l/day was 1.46 (1.20-1.78), with a higher risk among men (OR=1.50, 1.21-1.88). No increased risk was observed for the same intake groups of nontap water in men (OR=0.97, 0.77-1.22) or in women (OR=0.85, 0.50-1.42). Increased bladder cancer risks were observed for an intake of >5 cups of coffee daily vs. <5 and for THM exposure, but neither exposure confounded or modified the OR for tap water intake. The association of bladder cancer with tap water consumption, but not with nontap water fluids, suggests that carcinogenic chemicals in tap water may explain the increased risk.

Postura materna durante a gestação e sua influência sobre o peso ao nascer

To analyze the relationship between maternal posture/physical activity and inadequate birthweight. Prospective cohort study involving 152 pregnant women from a public low-risk antenatal care facility. Three interviews evaluating the frequency of physical activity were administered to each pregnant woman during gestation. Birthweight (inadequate when <3,000 g and adequate when > or =3,000 g) was the dependent variable and the frequency of physical activity the independent variable. Statistical analysis was performed using logistic univariate analysis and multiple regression controlling for schooling, smoking, living with spouse, and baseline nutritional status. The practice of walking for at least 50 minutes during the first period of pregnancy was identified as a protective factor against inadequate birthweight (adjusted OR=0.44; 95% CI: 0.20-0.98). Standing for 2.5 hours or longer during the second semester of pregnancy was associated with increased risk (adjusted OR=3.23; 95% CI: 1.30-7.99). Dose-response relationships were identified for washing clothing by hand and cooking (p-value for linear trend <0.01 and 0.05, respectively). After confounder control, only washing clothing during the second trimester of gestation remained statistically significant. Our results show the importance of medical orientation regarding posture and physical activity during antenatal care, aiming at the reduction of inadequate birthweight.

Is the association of birth weight with premenopausal breast cancer risk mediated through childhood growth?

Several studies have found positive associations between birth weight and breast cancer risk at premenopausal ages. The mechanisms underlying this association are not known, but it is possible that it may be mediated through childhood growth. We examined data from a British cohort of 2176 women born in 1946 and for whom there were prospective measurements of birth weight and of body size throughout life. In all, 59 breast cancer cases occurred during follow-up, 21 of whom were known to be premenopausal. Women who weighed at least 4 kg at birth were five times (relative risk (RR)=5.03; 95% confidence interval=1.13, 22.5) more likely to develop premenopausal breast cancer than those who weighed less than 3 kg (P-value for linear trend=0.03). This corresponded to an RR of 2.31 (0.95, 5.64) per 1 kg increase in birth weight. Birth weight was also a predictor of postnatal growth, that is, women who were heavy at birth remained taller and heavier throughout their childhood and young adulthood. However, the effect of birth weight on premenopausal breast cancer risk was only reduced slightly after simultaneous adjustment for height and body mass index (BMI) at age 2 years and height and BMI velocities throughout childhood and adolescence (adjusted RR=1.94 (0.74, 5.14) per 1 kg increase in birth weight). The pathways through which birth weight is associated with premenopausal breast cancer risk seem to be largely independent of those underlying the relation of postnatal growth to risk.

BLADDER CANCER AND EXPOSURE TO DISINFECTION BYPRODUCTS IN WATER THROUGH INGESTION, BATHING, SHOWERING AND SWIMMING IN POOLS: FINDINGS FROM THE SPANISH BLADDER CANCER STUDY

ISEE-241 Introduction: Exposure to disinfection by-products (DBP) in drinking water has been associated with increased bladder cancer risk. At high doses, several byproducts are mutagens and animal carcinogens. Trihalomethanes (THM), the most prevalent DBP, are highly volatile. Previous epidemiological studies focused on exposure through ingestion of drinking water, although recent studies have shown the relevance of other routes. We evaluated the association between increased bladder cancer risk and DBP exposure through ingestion of drinking water as well as inhalation and dermal absorption during showering, bathing and swimming pool use, employing THM level as a marker of DBP exposure. Methods: We conducted a hospital-based case-control study in Spain between June, 1998 and June, 2001, including 1,226 cases and 1,271 controls (87% males). Lifetime residential history, source and amount of drinking water, as well as adult habits for bathing, showering and swimming pool use, were recorded. This information was linked with current measures of THM levels in drinking water and with extensive historical data from local authorities and water treatment plants. Odds ratios (OR) and 95% confidence intervals (CI) were calculated through logistic regression adjusting for age, gender, region, smoking status, education, urbanicity of residence, fruit and vegetable intake and overall quality of interview. Results: Average household THM level, an index evaluating all routes of exposure, was associated with an increased bladder cancer risk. OR=1.99 (95% CI=1.03–3.86) for average residential THM level >49 □g/l relative to ≤8 □g/l (p value for linear trend=0.012). For exposure to THM via ingestion, OR for the highest quartile (<35 □g/day), relative to non-exposure, was 1.38 (95% CI=0.9–2.0). Duration of showering and bathing, weighted by average residential THM level, was associated with an OR of 1.89 (95% CI=1.2–3.0) for ≥333 compared with >50 minutes/day x □g/L (p-value for linear trend=0.006). Ever attending a swimming pool was associated with increased risk, OR=1.59, 95% CI=1.2–2.1. Discussion: This is the first study to evaluate non-ingestion exposure routes to DBP and bladder cancer. Exposure misclassification due to the considerable temporal and spatial variability of THM levels within municipality, and the difficulties in recalling lifetime habits, probably resulted in non-differential misclassification and underestimation of the point estimates. These results support the hypothesis that long-term exposure to THM at levels currently observed in many industrialized countries is associated with an increased bladder cancer risk and are the first epidemiologic data suggesting the importance of inhalation and dermal absorption of THM.

Folate intake and the risk of neural tube defects: an estimation of dose-response.

Studies have shown that folic acid supplementation in early pregnancy markedly reduces the risk of neural tube defects (NTDs). Investigation of the relation between relative dose of supplemental folic acid or total folate intake and NTD risk is limited. We used data from 23,228 women, predominantly from the northeastern United States, enrolled between October 1984 and June 1987 in a prospective study of early prenatal exposures and pregnancy outcomes. Diet and vitamin intake data were gathered in the early second trimester. NTDs were ascertained through prenatal testing and by report of the delivering physician. Data analyses included multiple logistic regression and restricted spline regression modeling. For each additional 500 dietary folate equivalents consumed per day, the prevalence of NTDs decreased by 0.78 cases (95% confidence interval [CI] = 0.47-1.09) per 1,000 pregnancies. Compared with women having the lowest total folate intakes (0-149 folate equivalents per day), the prevalence of NTDs declined by 34%, 30%, 56% and 77% among the offspring of those women consuming 150-399, 400-799, 800-1199 and > or = 1200 folate equivalents per day, respectively (P-value for linear trend = 0.016). Our results suggest that NTD risk declines markedly with modest increases of total folate in early pregnancy. Total folate dose, rather than supplemental folate alone, should be considered in formulating public health guidelines for NTD prevention.

The association between mental distress and the use of alternative medicine among cancer patients in North Norway.

To study the association between mental distress and the use of alternative medicine (AM) among cancer patients. A longitudinal questionnaire-based study was carried out at the Department of Oncology, University Hospital of Tromsø, Norway, during the period 1990-1991. The level of mental distress in 158 patients aged less than 75 years was assessed 4 months after first admission to the cancer ward. The patients answered five questions about mental distress selected from the General Health Questionnaire (GHQ). The questions were scored continuously according to the Likert scoring procedure. The level of mental distress was also ranked from 1 (little or no mental distress) to 3 (high mental distress). A total of 53 of the 158 patients reported use of AM at inclusion of the study or during the 4 months of follow-up. Among patients with low mental distress, 21% were users of AM, 36% of patients with medium distress and 48% in patients with high level of mental distress (p-value for linear trend = 0.02). Adjusted for all known relevant variables, patients with medium level of mental distress had 1.9 times higher prevalence of use of AM than patients with low level of mental distress, patients with high mental distress had a 2.9 times higher prevalence (p = 0.15 and 0.07, respectively). Analyzed as a continuous variable (Likert score between 5 and 20), mental distress was associated with use of AM (p = 0.007). These findings suggest that seeking alternative treatment is more common among mentally distressed cancer patients.

Functional status of the paretic arm affects the loss of bone mineral in the proximal humerus after stroke: a 1-year prospective study.

The aim of this study was to evaluate the effect of decreased arm function after stroke on bone mineral density (BMD) in the proximal humerus. Twenty-five patients were evaluated 1 week after acute stroke and reevaluated 2 months, 7 months, and 1 year after the stroke. BMD of the proximal humerus was measured and the functional status of the paretic arm was assessed. Within 1 year the BMD decreased significantly in the proximal humerus at the paretic side. No significant BMD change was found at the nonparetic side. Patients with an initial completely paralyzed arm lost 27% (P <0.001), those with severe to moderate paresis lost 11% (P <0.001), and patients with minor or no paresis had no significant bone loss in the proximal humerus at the paretic side after 1 year. A statistically significant trend with initial arm function was found both 7 months and 1 year after the stroke at the paretic side (P <0.01). Patients who were paralyzed or had severe to moderate paresis both at inclusion and after 1 year had a larger 1-year bone loss in the proximal humerus than the patients who recovered and these who had only minor impairment throughout the study, 25%, 8%, and 5%, respectively (P-value for linear trend <0.001). We conclude that during the first year after stroke bone mineral is lost in the proximal humerus of the paretic arm, but that the loss depends on the initial degree of paresis. The loss may be prevented if arm function is regained.

Cancer incidence among European man-made vitreous fiber production workers.

This study analyzed cancer incidence among man-made vitreous fiber workers. A cancer incidence follow-up was conducted among 3685 rock-slag wool (RSW) and 2611 glass wool (GW) production workers employed for > or =1 year in Denmark, Finland, Norway, or Sweden, and the standardized incidence ratios (SIR) were calculated on the basis of national incidence rates. Overall cancer incidence was close to expectation. Lung cancer incidence was increased among the RSW [SIR 1.08, 95% confidence interval (95% CI) 0.85-1.36] and GW (SIR 1.28, 95% CI 0.91-1.74) workers. For both subcohorts, a trend was suggested for time since first employment (P-value for linear trend 0.1 and 0.2, respectively). Neither subcohort showed an association with employment during the early technological phase, when fiber exposure was high. The incidence of oral, pharyngeal, and laryngeal cancer was increased among the RSW (SIR 1.46, 95% CI 0.99-2.07) and the GW (SIR 1.41, 95% CI 0.80-2.28) subcohorts. Despite a trend in risk for these neoplasms among the GW workers with time since first employment, the lack of a positive relation with other indirect indicators of fiber exposure points against a causal interpretation. No association between RSW or GW exposure and the risk of other neoplasms was suggested. These lung cancer results are similar to those of a mortality study that included a larger number of factories. For other cancers there was no suggestion of an association with RSW or GW exposure.

Does high soy milk intake reduce prostate cancer incidence? The Adventist Health Study (United States)

Recent experimental studies have suggested that isoflavones (such as genistein and daidzein) found in some soy products may reduce the risk of cancer. The purpose of this study was to evaluate the relationship between soy milk, a beverage containing isoflavones, and prostate cancer incidence. A prospective study with 225 incident cases of prostate cancer in 12,395 California Seventh-Day Adventist men who in 1976 stated how often they drank soy milk. Frequent consumption (more than once a day) of soy milk was associated with 70 per cent reduction of the risk of prostate cancer (relative risk = 0.3, 95 percent confidence interval 0.1-1.0, p-value for linear trend = 0.03). The association was upheld when extensive adjustments were performed. Our study suggests that men with high consumption of soy milk are at reduced risk of prostate cancer. Possible associations between soy bean products, isoflavones and prostate cancer risk should be further investigated.

Coffee and Methylxanthines and Breast Cancer: A Case-Control Study&lt;xref ref-type="fn" rid="FN2"&gt;2&lt;/xref&gt;

A dietary case-control study based on 818 newly diagnosed breast cancer (BC) patients was conducted in Israel between 1975 and 1978. The role of coffee and total methylxanthine intake from coffee, tea, cola, chocolate, and cocoa drinks was evaluated in the BC patients as compared to that in two matched control populations [surgical controls (SC) and neighborhood controls (NC)]. Because it has been suggested that caffeine enhances mammary carcinogenesis in rats fed high polyunsaturated fat diets, analysis was done also in relation to fat consumption. When comparison was done to both matched control groups, a nonsignificant negative association was found between consumption of cups of coffee and BC (odds ratios of greater than or equal to 4 cups of coffee/day vs. less than or equal to 1 per week = 0.6 for BC/NC and 0.7 for BC/SC). This association was observed in all 3 ethnic subgroups studied. The pattern was stronger among the high-fat consumers after controlling for several hormonal confounding factors (two-tailed P-value for linear trend = 0.06 for SC and P = 0.05 for NC). In addition, when the consumption of methylxanthine of BC patients was compared to that of benign breast patients, adjusted by age and ethnic group, a diminished risk was found (odds ratio for BC of the highest level of methylxanthine vs. lowest level = 0.59).