Prediagnostic hematocrit values and subsequent cancer risk.
In this prospective study, the association between hematocrit values measured in 1965-68 and subsequent cancer incidence was studied among 7737 Japanese-American men in Hawaii. With an increase in hematocrit levels, there was an increasing risk for lung cancer, especially squamous or small cell type, and for kidney cancer. However, a statistically significant trend remained only for kidney cancer after adjusting for smoking history. The relative risk for kidney cancer was 4.94 (95% confidence interval, 1.03-23.63) for subjects with hematocrit values of 47 or higher compared with those with hematocrit values of 43 or lower. In contrast, the risk of oral-pharyngeal cancer decreased with increasing hematocrit levels. With adjustment for cigarette smoking and alcohol intake, the relative risk for oral-pharyngeal cancer was 0.20 (95% confidence interval, 0.04-0.88) for subjects with hematocrit values of 47 or higher compared with those with hematocrit values of 43 or lower. The association with kidney or oral-pharyngeal cancer was not affected by the time interval between examination and diagnosis of these cancers (< or = 10 and > 10 years). Erythropoietin production by kidney tumors and micronutrient deficiencies in oral-pharyngeal cancer cases may partially account for these results.
Kato
I
I
Japan-Hawaii Cancer Study, Kuakini Medical Center, Honolulu 96817.
Nomura
A
A
Stemmermann
G N
GN
Chyou
P H
PH
D000328:Adult; D000428:Alcohol Drinking / Q000009:adverse effects; D006254:Hawaii / Q000453:epidemiology; D006400:Hematocrit; D006801:Humans; D015994:Incidence; D007564:Japan / Q000208:ethnology; D008297:Male; D008875:Middle Aged; D009369:Neoplasms / Q000097:blood / Q000453:epidemiology* / Q000208:ethnology; D011159:Population Surveillance; D016016:Proportional Hazards Models; D011446:Prospective Studies; D012307:Risk Factors; D012907:Smoking / Q000009:adverse effects