Discussion
Myocardial infarction (MI) and ischemic stroke are the leading causes of
mortality and morbidity in patients with type 2
diabetes.18 The strength of the evidence for the use
of antiplatelet agents as secondary prevention19-22has led to the suggestion that Aspirin might be helpful for primary
prevention of cardiovascular events in diabetes.
In order to evaluate the role of Aspirin in the prevention of
cardiovascular events, especially in diabetic patients, the primitive
search of the present meta-analysis was compared to its risk of
bleeding. Similarly, to compare the benefits over the harms of Aspirin,
the chances of risk of all-cause death, CVS-related death, MI, stroke,
and risk of bleeding were compared between the patients taking Aspirin
and no aspirin group (placebo).
When the odds ratio of all-cause death was compared with Aspirin plus
placebo in diabetic patients, the confidence intervals slightly crossed
the line of no effect, which shows an average odds ratio of 0.86. It
signifies that the p>0.05 has no specific effect of Aspirin
on all-cause death in diabetes. The average odds ratio of CVS-related
death compared to Aspirin with placebo in diabetic patients was
insignificant with a value of 1.0; CI varied from 0.61 to 1.63, showing
no significant role of Aspirin in CVS-related death. The chances of the
risk of MI in aspirin patients were also insignificant compared with
placebo with a confidence interval of 0.9, slightly crossing the line of
no effect. The possibility of a chance of stroke in the aspirin group
was also insignificant, with a p-value of 0.93, resulting in no specific
risk of Aspirin for stroke in diabetic patients. There were no
differences in the rates of bleeding outcomes between patients who
received Aspirin and those who received a placebo.
All included trials were consistent in reporting that no significant
effect of Aspirin on primary prevention of CV events in individuals with
diabetes, which is similar to the present meta-analysis except for the
JPAD trial15; which significantly reported lower risk
in the aspirin group when compared with placebo showing an inefficacy of
low dose of Aspirin. A follow-up study of 10 years was performed for the
same trial, which together constitutes the JPAD2
study23 which concluded that a low dose of Aspirin has
no role in the risk of CV events but included an increased risk of
gastrointestinal bleeding. A recent trial by ASCEND
group17 only showed the beneficial effect of Aspirin
in preventing serious vascular events in diabetic patients with no
cardiovascular events.
Several Meta-analyses and randomized trials have been previously
conducted to rule out the role of Aspirin in the primary prevention of
cardiovascular events, including diabetic patients. However, due to the
low ratio of diabetic patients in the studies as mentioned in Table 1,
these studies were excluded in the present meta-analysis to reduce the
chances of risk of bias as there was the inability to perceive event
rate data specifically for patients with diabetes.