Alcohol consumption and risk of non-Hodgkin lymphoma: a pooled analysis.
BACKGROUND
Previous epidemiological studies of the relation between alcohol consumption and risk of non-Hodgkin lymphoma (NHL) have been inconsistent, probably because of small sample sizes of individual studies that result from stratification by NHL subtype and type of alcoholic beverage. We aimed to assess the role of alcohol consumption in NHL with sufficient sample size to analyse by both type of alcoholic beverage and disease subtype.


METHODS
We obtained original data from nine case-control studies from the USA, UK, Sweden, and Italy in the International Lymphoma Epidemiology Consortium (InterLymph), yielding a pooled study population of 15 175 individuals (6492 cases and 8683 controls). We derived odds ratios (OR) and 95% CI from unconditional logistic regression models, controlling for study centre and other confounding factors. Heterogeneity between studies was assessed by comparison of results from joint fixed-effects logistic regression and two-stage random-effects logistic regression, and by calculation of Wald chi(2) statistics.


RESULTS
People who drank alcohol had a lower risk of NHL than did non-drinkers (OR 0.83 [95% CI 0.76-0.89]). Compared with non-drinkers, risk estimates were lower for current drinkers than for former drinkers (0.73 [0.64-0.84] vs 0.95 [0.80-1.14]), but risk did not decrease with increasing alcohol consumption. The protective effect of alcohol did not vary by beverage type, but did change with NHL subtype. The lowest risk estimates were recorded for Burkitt's lymphoma (0.51 [0.33-0.77]).


CONCLUSIONS
People who drink alcoholic beverages might have a lower risk of NHL than those who do not, and this risk might vary by NHL subtype. Further study designs are needed to determine whether confounding lifestyle factors or immunomodulatory effects of alcohol explain this association.
Morton
Lindsay M
LM
Department of Epidemiology and Public Health, Yale University School of Medicine, New Haven, CT, USA.
Zheng
Tongzhang
T
Holford
Theodore R
TR
Holly
Elizabeth A
EA
Chiu
Brian C H
BC
Costantini
Adele Seniori
AS
Stagnaro
Emanuele
E
Willett
Eleanor V
EV
Dal Maso
Luigino
L
Serraino
Diego
D
Chang
Ellen T
ET
Cozen
Wendy
W
Davis
Scott
S
Severson
Richard K
RK
Bernstein
Leslie
L
Mayne
Susan T
ST
Dee
Fred R
FR
Cerhan
James R
JR
Hartge
Patricia
P
D000293:Adolescent; D000328:Adult; D000368:Aged; D000428:Alcohol Drinking; D016022:Case-Control Studies; D005260:Female; D006801:Humans; D008228:Lymphoma, Non-Hodgkin / Q000453:epidemiology*; D008297:Male; D008875:Middle Aged; D016017:Odds Ratio; D012307:Risk Factors