Blood types and heart attack risks

RhD negative subjects have increased the risk of developing of certain heart diseases, respiratory diseases and some immunity and autoimmunity related diseases, for example rheumatoid arthritis. The general pattern suggests that RhD negative subjects could have problems with autoimmunity, could be more resistant to infections of viral origin and could be less resistant to infections of bacterial origin.

Harvard:

Pooling data from two long-running research studies that tracked 89,500 adults over 20 years, the researchers found that people with blood type AB were 23% more likely to develop heart disease than others. Those with type B had an 11% increased risk, and those with type A had a 5% increased risk.

https://www.hsph.harvard.edu/news/hsph-in-the-news/qi-blood-type-heart-disease-risk/#:~:text=Pooling%20data%20from%20two%20long,had%20a%205%25%20increased%20risk.