Aspirin in Diabetes (in Doubt?)

Extracted from :No benefits of aspirin for primary prevention in diabetics, meta-analysis suggests November 10, 2009 | Shelley Wood (http://www.theheart.org/article/1020401.do)

Another meta-analysis—this one focused on diabetics—is questioning the role of aspirin for the primary prevention of cardiovascular events [1]. Writing in a paper published online November 6, 2009 in BMJ, Dr Giogria De Berardis (Consorzio Mario Negri Sud, Maria Imbaro, Italy) and colleagues conclude that "a clear benefit of aspirin in the primary prevention of major cardiovascular events in people with diabetes remains unproved."

Effect of aspirin compared with placebo or no aspirin on relative risk of clinical events in patients with diabetes

End point	Relative risk	95% CI	p
Major cardiovascular events	0.90	0.81-1.00	0.06
MI	0.86	0.61-1.21	0.37
Stroke	0.83	0.60-1.14	0.25
Cardiovascular death	0.94	0.72-1.23	0.68
All-cause mortality	0.93	0.82-1.05	0.22
Any bleeding	2.50	0.76-8.21	NS

"In the most recent guidelines from the Canadian Diabetes Association, for the first time they fully acknowledged the lack of definite data on the efficacy of aspirin, and they leave to the physician the decision of whether or not to use aspirin based on the characteristics of the individual patients. And the other [guideline groups] are starting to move from certainty to uncertainty as well."

There's strong basic research evidence suggesting that diabetes can represent a particular situation associated with poor response of platelets to aspirin, and there are many reasons for that," Nicolucci noted. "Diabetes is associated with hyperglycemia, hyperinsulinemia, insulin resistance, oxidative stress, and advanced glycation end products, and all these factors can be responsible for activation of platelets [via] different pathways that are not blocked by aspirin."

Related papers:

1. De Berardis G, Sacco M, Strippoli GFM, et al. Aspirin for primary prevention of cardiovascular events in people with diabetes: Meta-analysis of randomised controlled trials. BMJ 2009; DOI:10.1136/bmj.b4531. Available at: http://www.bmj.com.
2. Antithrombotic Trialists' (ATT) Collaboration. Aspirin in the primary and secondary prevention of vascular disease: collaborative meta-analysis of individual participant data from randomised trials. Lancet 2009; 373:1849-1860.
3. Antithrombotic Trialists' Collaboration. Collaborative meta-analysis of randomised trials of antiplatelet therapy for prevention of death, myocardial infarction, and stroke in high risk patients. BMJ 2002; 324:71-86.
4. Haynes R, Bowman L, Armitage J. Aspirin for primary prevention of vascular disease in people with diabetes. BMJ 2009; DOI:10.1136/bmj.b4596. Available at: http://www.bmj.com.

(also in http://gettoknowdrugs.blogspot.com/)