Risk factors for multiple myeloma: a hospital-based case-control study in Northwest China.
BACKGROUND
The distinctive racial/ethnic and geographic distribution of multiple myeloma (MM) suggests that both family history and environmental factors may contribute to its development.


METHODS
A hospital-based case-control study consisting of 220 confirmed MM cases and 220 individually matched patient controls, by sex, age and hospital was carried out at 5 major hospitals in Northwest China. A questionnaire was used to obtain information on demographics, family history, and the frequency of food items consumed.


RESULTS
Based on multivariate analysis, a significant association between the risk of MM and family history of cancers in first degree relatives was observed (OR=4.03, 95% CI: 2.50-6.52). Fried food, cured/smoked food, black tea, and fish were not significantly associated with the risk of MM. Intake of shallot and garlic (OR=0.60, 95% CI: 0.43-0.85), soy food (OR=0.52, 95% CI: 0.36-0.75) and green tea (OR=0.38, 95% CI: 0.27-0.53) was significantly associated with a reduced risk of MM. In contrast, intake of brined vegetables and pickle was significantly associated with an increased risk (OR=2.03, 95% CI: 1.41-2.93). A more than multiplicative interaction on the decreased risk of MM was found between shallot/garlic and soy food.


CONCLUSIONS
Our study in Northwest China found an increased risk of MM with a family history of cancer, a diet characterized by low consumption of garlic, green tea and soy foods, and high consumption of pickled vegetables. The effect of green tea in reducing the risk of MM is an interesting new finding which should be further confirmed.
Department of Hematology, Xijing Hospital, Fourth Military Medical University, Xi'an, Shaanxi 710032, China. wangqixia_@hotmail.com
Qixia
Q
Wang
Yiwei
Y
Wang
Zhaohua
Z
Ji
Xiequn
X
Chen
Yaozhu
Y
Pan
Guangxun
G
Gao
Hongtao
H
Gu
Yang
Y
Yang
Bernard C K
BC
Choi
Yongping
Y
Yan
D016022:Case-Control Studies; D015984:Causality; D002681:China / Q000453:epidemiology; D016001:Confidence Intervals; D004781:Environmental Exposure / Q000032:analysis; D005192:Family Health; D005247:Feeding Behavior / Q000208:ethnology*; D005260:Female; D005519:Food Preservation / Q000379:methods; D005737:Garlic; D006801:Humans; D008297:Male; D008875:Middle Aged; D009101:Multiple Myeloma / Q000453:epidemiology* / Q000517:prevention & control*; D011159:Population Surveillance; D011237:Predictive Value of Tests; D012307:Risk Factors; D040242:Risk Reduction Behavior; D045730:Soy Foods; D011795:Surveys and Questionnaires; D013662:Tea
D013662:Tea