[Effects of low-dose aspirin on primary prevention of cardiovascular events: a systematic review].
OBJECTIVE
To evaluate the effect and safety of low-dose aspirin for primary prevention of cardiovascular events.


METHODS
We searched for randomized controlled trials (RCT) in the following electronic databases: MEDLINE, EMbase, the Cochrane Library (Issue 3, 2008), CBM, CNKI. Quality assessment and data extraction were conducted by two reviewers independently. All data were analyzed using Review Manager 4.2.


RESULTS
Six studies (TPT, HOT, PPP, WHS, POPADAD, J-PAD) involving a total of 72,466 participants met the inclusion criteria. Meta-analysis results showed that: (1) Compared with placebo, the incidences of total cardiovascular events (RR = 0.85, 95% CI: 0.80-0.92), stroke (RR = 0.87, 95% CI: 0.77-0.98), nonfatal stroke (RR = 0.81, 95% CI: 0.70-0.95) and transient ischemic attack (RR = 0.76, 95% CI: 0.64-0.90) were significantly lower in low-dose aspirin group than those in placebo control group (all P < 0.05). (2) Nonfatal myocardial infarction (RR = 0.89, 95% CI: 0.77-1.02), death from cardiovascular causes (RR = 0.98, 95% CI: 0.86-1.13) and death from any cause (RR = 0.95, 95% CI: 0.88-1.02) were similar between the 2 groups (all P > 0.05). (3) The risk of coronary heart disease was reduced in low-dose aspirin group in the elderly (RR = 0.81, 95% CI: 0.70-0.94, P < 0.05). (4) The risk of bleeding was higher in low aspirin group compared to placebo group (RR = 1.15, 95% CI: 1.12-1.18, P < 0.01).


CONCLUSIONS
Low-dose aspirin use could reduce the incidences of total cardiovascular events, stroke, nonfatal stroke and transient ischemic attack but increase the risk of bleeding, the incidence of nonfatal myocardial infarction, death from cardiovascular causes and death from any cause was not affected by low-dose aspirin use. Low-dose aspirin use was also significantly reduced the risk of coronary heart disease in the elderly.
Tang
Hai-qin
HQ
Department of Geriatrics, First Affiliated Hospital of Anhui Medical University, Hefei 230022, China. tanghq898@sina.com.cn
Yang
Lin-lin
LL
Hu
Shi-lian
SL
Shen
Gan
G
Sun
Ye-huan
YH
Huang
Xiao-hui
XH
Li
Jie-hua
JH
Xu
Ting-juan
TJ
D001241:Aspirin / Q000008:administration & dosage / Q000009:adverse effects* / Q000627:therapeutic use*; D002318:Cardiovascular Diseases / Q000188:drug therapy*; D006801:Humans; D010975:Platelet Aggregation Inhibitors / Q000008:administration & dosage / Q000009:adverse effects* / Q000627:therapeutic use*; D011322:Primary Prevention; D016032:Randomized Controlled Trials as Topic; D016896:Treatment Outcome
D010975:Platelet Aggregation Inhibitors; D001241:Aspirin