Physical activity and risk of prostate and bladder cancer in China: The South and East China case-control study on prostate and bladder cancer.

BACKGROUND: Recent meta-analyses have suggested a modest protective effect of high levels of physical activity on developing both prostate and bladder cancer, but significant heterogeneity between studies included in these meta-analyses existed. To our knowledge, few Chinese studies investigated the association between physical activity and prostate cancer and none between physical activity and bladder cancer. Given the inconsistencies between previous studies and because studies on the relation between physical activity and prostate and bladder cancer in China are scarce, it remains elusive whether there is a relationship between physical activity and prostate and bladder cancer within the Chinese population. METHODS: We investigated the association between physical activity and risk of developing prostate and bladder cancer within a hospital-based case-control study in the East and South of China among 260 and 438 incident prostate and bladder cancer cases, respectively, and 427 controls. A questionnaire was administered to measure physical activity as metabolic equivalents (METs). Random effects logistic regression was used to calculate odds ratios (ORs) of prostate and bladder cancer for different levels of physical activity and for the specific activities of walking and cycling. RESULTS: Increasing overall physical activity was associated with a significant reduction in prostate cancer risk (Ptrend = 0.04) with the highest activity tertile level showing a nearly 50% reduction in prostate cancer risk (OR = 0.53, 95%CI: 0.28-0.98). Overall physical activity was not significantly associated with risk of bladder cancer (Ptrend = 0.61), neither were vigorous (Ptrend = 0.60) or moderate levels of physical activity (Ptrend = 0.21). Walking and cycling were not significantly associated with either prostate (Ptrend> = 0.62) or bladder cancer risk (Ptrend> = 0.25). CONCLUSIONS: The findings of this largest ever case-control study in China investigating the relationship between physical activity and prostate and bladder cancer suggest that overall physical activity is associated with a decreased risk of prostate cancer, but not with bladder cancer.

Dietary consumption and diet diversity and risk of developing bladder cancer: results from the South and East China case-control study.

BACKGROUND: The epidemiologic evidence on the role of dietary consumption on the risk of bladder cancer in the Chinese population is limited. We investigated the role of dietary consumption and diet diversity on the risk of developing bladder cancer within a Chinese population. METHODS: A case-control study of 487 cases and 469 controls was conducted in four hospitals in China. A food frequency questionnaire was used to gather information on the consumption of 35 food items. Unconditional logistic regression models were used to derive odds ratios (ORs) and corresponding 95 % confidence intervals (95 % CI) for the relationship between dietary factors, dietary diversity scores, and bladder cancer. RESULTS: The ORs of bladder cancer for red meat (OR = 1.8, 95 % CI:1.1-3.0;p(trend) = 0.01), organ meat (OR = 1.6, 95 % CI:0.9-2.9;p(trend) = 0.04), leafy vegetables (OR = 2.9, 95 % CI:1.6-5.4;p trend = 0.003), bulb vegetables (OR = 2.3, 95 % CI:1.3-4.0;p(trend) = 0.003), and preserved vegetables (OR = 2.3, 95 % CI:1.2-4.2;p(trend) = 0.02) were significantly increased when comparing the highest to lowest level of consumption. The ORs for white fresh fish (OR = 0.5, 95 % CI:0.3-0.9;p(trend) = 0.004), citrus fruits (OR = 0.4, 95 % CI:0.3-0.8;p(trend) = 0.007), stone fruits (OR = 0.4, 95 % CI:0.2-0.6;p(trend) < 0.001), vine fruits (OR = 0.5, 95 % CI:0.2-1.0;p(trend) = 0.02), flower vegetables (OR = 0.3, 95 % CI:0.2-0.6;p(trend) < 0.001), potatoes (OR = 0.4, 95 % CI:0.2-0.9;p(trend) = 0.005), or dairy products (OR = 0.4, 95 % CI:0.3-0.7;p(trend) < 0.001) were significantly decreased when comparing the highest to lowest level of consumption. Subjects with the highest total diet diversity (OR = 0.4, 95 % CI:0.2-1.1;p(trend) = 0.02) and fruit diversity (OR = 0.1, 95 % CI:0.0-0.3;p(trend) < 0.001) had reduced ORs of and compared to subjects with the lowest diversity. CONCLUSION: Our results indicate that a diet with higher total diet diversity and in particular fruit diversity may reduce the risk of bladder cancer.

Fluid intake and the risk of bladder cancer: results from the South and East China case-control study on bladder cancer.

Although several studies have assessed the association between total fluid intake, specific drinks and bladder cancer, no firm conclusions can yet be drawn. Four hundred thirty two bladder cancer cases and 392 frequency matched hospital-based controls recruited in the South and East of China between October 2005 and June 2008 were interviewed on their intake of 6 nonalcoholic and 3 alcoholic drinks. Age, sex, smoking and hospital-adjusted odds ratios (OR) and 95 percent confidence intervals (95% CI) were calculated for all drinks and for total fluid intake using logistic regression. For 381 cases (81.9% men) and 371 controls (76.3% men), total fluid intake could be calculated. In men, an increase in total fluid intake was associated with a significantly decreased bladder cancer risk (OR 0.93, 95% CI: 0.88-0.99, per cup fluid consumed). Neither green nor black tea consumption was associated with bladder cancer. Daily consumption of milk significantly reduced the risk of bladder cancer by a half (OR 0.49, 95% CI: 0.32-0.76), which strengthens earlier suggestions that milk is probably associated with a decreased bladder cancer risk. Consumption of wine (OR 0.49, 95% CI: 0.34-0.70) and liquor/spirits (OR 0.65, 95% CI: 0.47-0.92) were associated with a significantly reduced risk. Consumption of water, fruit juice and beer appeared not associated with bladder cancer. There is no clear indication that the risks observed in this Chinese population are substantially different from those observed in Caucasian populations.

The effect of smoking on the male excess of bladder cancer: a meta-analysis and geographical analyses.

Smoking is considered the primary risk factor for bladder cancer. Although smoking prevalence and bladder cancer incidence vary around the world, bladder cancer is on average 4 times more common in males than in females. This article describes the observed male-female incidence ratio of bladder cancer for 21 world regions in 2002 and 11 geographical areas during the time period 1970-1997. A meta-analysis, including 34 studies, was performed to ascertain the increased risk for bladder cancer in males and females when smoking. The summary odds ratios (SORs) calculated in the meta-analysis were used to estimate the male-female incidence ratio of bladder cancer that would be expected for hypothetical smoking prevalence scenarios. These expected male-female incidence ratios were compared with the observed ratios to evaluate the role of smoking on the male excess of bladder cancer. The male-female incidence ratio of bladder cancer was higher than expected worldwide and over time, based on a smoking prevalence of 75% in males, 10% in females and an increased risk (SOR) of bladder cancer associated with smoking of 4.23 for males and 1.35 for females, respectively. This implied that, at least in the Western world, smoking can only partially explain the difference in bladder cancer incidence. Consequently, other factors are responsible for the difference in bladder cancer incidence.

Pooled analysis and meta-analysis of the glutathione S-transferase P1 Ile 105Val polymorphism and bladder cancer: a HuGE-GSEC review.

The glutathione S-transferase P1 genotype (GSTP1) is involved in the inactivation of cigarette smoke carcinogens, and sequence variation in the gene may alter bladder cancer susceptibility. To examine the association between GSTP1Ile 105Val and bladder cancer, the authors undertook a meta- and pooled analysis. Summary crude and adjusted odds ratios and corresponding 95% confidence intervals were pooled by using a random-effects model. In the meta-analysis (16 studies, 4,273 cases and 5,081 controls), the unadjusted summary odds ratios for GSTP1 Ile/Val and Val/Val compared with GSTP1 Ile/Ile were 1.54 (95% confidence interval: 1.21, 1.99; p < 0.001) and 2.17 (95% confidence interval: 1.27, 3.71; p = 0.005). The association appeared to be the strongest in Asian countries. When the analysis was limited to European descendents (nine studies), the summary odds ratio decreased (odds ratio = 1.24, 95% confidence interval: 1.00, 1.52) (Q = 17.50; p = 0.02). All relevant data previously contributed to the International Study on Genetic Susceptibility to Environmental Carcinogens were pooled (eight studies, 1,305 cases and 1,558 controls). The summary odds ratios were similar to the ones from the meta-analysis. Case-only analyses did not detect an interaction between the GSTP1 genotype and smoking status (never/ever). GSTP1 Ile 105Val appears to be associated with a modest increase in the risk of bladder cancer.

Occupational risks for nasal cancer in Sweden.

An elevated risk of nasal cancer (NC) has been associated with numerous occupations but with contradicting results. We sought to address recent and current risks of NC in a nationwide study. The nationwide Swedish Family-Cancer Database was used to calculate standardized incidence ratios (SIRs) for 52 occupational groups. SIRs were adjusted for age and socioeconomic status. Among 739 male cases, significantly elevated SIRs for nasal adenocarcinoma were observed in woodworkers, teachers, and fishermen. In woodworkers, the risk increased with a longer occupational history in exposure to softwood in combination with hardwood. Electrical workers had a significant elevated risk for squamous cell carcinoma. Among 182 female cases, significantly elevated SIRs were observed in glass, ceramic, and tile workers. The study identified some known risk occupations and suggested some new ones.