White blood cell count and renin-angiotensin system inhibitors for the risk of cancer in type 2 diabetes.
BACKGROUND
High white blood cell (WBC) predicted cancer-associated mortality and renin-angiotensin system (RAS) inhibitors have immunomodulating effects. We hypothesize that RAS inhibitors may reduce cancer risk associated with high WBC in type 2 diabetes mellitus (T2DM).


METHODS
A prospective cohort of 4570 Chinese T2DM patients, free of cancer at enrolment, were analyzed. Biological interaction between WBC groups and use of RAS inhibitors was estimated using relative excess risk due to interaction (RERI), attributable proportion due to interaction (AP) and synergy index (S). RERI>0, AP>0 or S>1 indicates biological interaction.


RESULTS
During 4.89 years of follow-up, 205 (4.49%) patients developed cancer. WBC > or = 8.2 x 10(9) counts/L plus non-use of RAS inhibitors was associated with elevated cancer risks in multivariable models. The RERI and AP for interaction between WBC > or = 8.2 x 10(9) counts/L and non-use of RAS inhibitors were, respectively, 1.26 (95% CI: 0.22-2.31) and 0.50 (0.23-0.78). In patients with WBC > or = 8.2 x 10(9) counts/L, use of RAS inhibitors was associated with 64% (31-81%) cancer risk reduction in multivariable analysis.


CONCLUSIONS
In T2DM, increased WBC predicts cancer while use of RAS inhibitors may reduce cancer risks associated with high WBC count.
Yang
Xilin
X
Department of Medicine and Therapeutics, The Chinese University of Hong Kong, Shatin, Hong Kong, SAR, China. yang.xilin@cuhk.edu.hk
Ma
Ronald C W
RC
So
Wing Yee
WY
Ko
Gary T C
GT
Kong
Alice P S
AP
Zhao
Hailu
H
Xu
Gang
G
Tong
Peter C Y
PC
Chan
Juliana C N
JC
D000806:Angiotensin-Converting Enzyme Inhibitors / Q000009:adverse effects* / Q000627:therapeutic use; D001794:Blood Pressure; D015992:Body Mass Index; D002784:Cholesterol / Q000097:blood; D003924:Diabetes Mellitus, Type 2 / Q000097:blood / Q000150:complications* / Q000453:epidemiology; D005260:Female; D006723:Hong Kong / Q000453:epidemiology; D006801:Humans; D007958:Leukocyte Count; D007962:Leukocytes / Q000187:drug effects / Q000502:physiology; D008297:Male; D008875:Middle Aged; D009369:Neoplasms / Q000097:blood / Q000453:epidemiology*; D010343:Patient Admission / Q000706:statistics & numerical data; D016016:Proportional Hazards Models; D012307:Risk Factors; D014280:Triglycerides / Q000097:blood
D000806:Angiotensin-Converting Enzyme Inhibitors; D014280:Triglycerides; D002784:Cholesterol