Meat and components of meat and the risk of bladder cancer in the NIH-AARP Diet and Health Study.
BACKGROUND
Meat could be involved in bladder carcinogenesis via multiple potentially carcinogenic meat-related compounds related to cooking and processing, including nitrate, nitrite, heterocyclic amines (HCAs), and polycyclic aromatic hydrocarbons (PAHs). The authors comprehensively investigated the association between meat and meat components and bladder cancer.


METHODS
During 7 years of follow-up, 854 transitional cell bladder-cancer cases were identified among 300,933 men and women who had completed a validated food-frequency questionnaire in the large prospective NIH-AARP Diet and Health Study. The authors estimated intake of nitrate and nitrite from processed meat and HCAs and PAHs from cooked meat by using quantitative databases of measured values. Total dietary nitrate and nitrite were calculated based on literature values.


RESULTS
The hazard ratios (HR) and 95% confidence intervals (CI) for red meat (HR for fifth quintile compared with first quintile, 1.22; 95% CI, 0.96-1.54; P(trend) = .07) and the HCA 2-amino-1 methyl-6-phenylimidazo(4,5-b)pyridine (PhIP) (HR, 1.19; 95% CI, 0.95-1.48; P(trend) = .06) conferred a borderline statistically significant increased risk of bladder cancer. Positive associations were observed in the top quintile for total dietary nitrite (HR, 1.28; 95% CI, 1.02-1.61; P(trend) = .06) and nitrate plus nitrite intake from processed meat (HR, 1.29; 95% CI, 1.00-1.67; P(trend) = .11).


CONCLUSIONS
These findings provided modest support for an increased risk of bladder cancer with total dietary nitrite and nitrate plus nitrite from processed meat. Results also suggested a positive association between red meat and PhIP and bladder carcinogenesis.
Ferrucci
Leah M
LM
Division of Cancer Epidemiology and Genetics, National Cancer Institute, National Institutes of Health, Department of Health and Human Services, Rockville, Maryland, USA.
Sinha
Rashmi
R
Ward
Mary H
MH
Graubard
Barry I
BI
Hollenbeck
Albert R
AR
Kilfoy
Briseis A
BA
Schatzkin
Arthur
A
Michaud
Dominique S
DS
Cross
Amanda J
AJ
D002295:Carcinoma, Transitional Cell / Q000209:etiology*; D019992:Databases as Topic; D004032:Diet / Q000009:adverse effects*; D005260:Female; D005511:Food Handling; D006801:Humans; D008297:Male; D008460:Meat / Q000009:adverse effects*; D008875:Middle Aged; D009566:Nitrates / Q000009:adverse effects; D009573:Nitrites / Q000009:adverse effects; D011795:Surveys and Questionnaires; D001749:Urinary Bladder Neoplasms / Q000209:etiology*
D009566:Nitrates; D009573:Nitrites