Cases of adult obesity have been rising in every age group and gender of the Saudi population. If this trend continues it can lead to drastically high incidences of diabetes and the coronary heart disease (CHD). In a recent 2014 world health survey by the WHO, Saudi Arabia was ranked 27 th in the world in CHD related deaths. Additionally in Saudi Arabia CHD was the leading cause of death in 2014. Therefore, in this study we decided to look at the possible correlation between the inheritance of blood group antigens and the high incidences of myocardial infarction (MI) among the adult male patients. Results of our study show that in the randomly selected male control group 20.7% were A + and 3.35% were A -while 14.3% were found to be B + and 3.95% were B -. AB blood group was the least prevalent blood group among the control population. Only 8.2% were found to be AB + and 2.43% were AB -. As previously reported by us and others O + blood group was the most prevalent blood group among the control population at 38.3% while only 8.5% were found to be O -. In contrast when we analyzed the blood group distribution among the 111 MI male patients our results showed a statistically significant reduction in the combined Rh -male MI patients as compared to the Rh -individuals in the control group. Additionally we found a significantly high prevalence of A + blood group (30.6%) among the MI patients as compared to the control population. Our results also showed a small but not a significant increase in B + and O + blood groups in MI patients as compared to the controls. Finally our results show statistically significant reduction in O -MI patients as compared to the control population. In conclusion A + individuals show statistically high incidences of MI and O -individuals show statistically low incidences of MI in male patients. Our results also show a statistically significant reduction in the Rh -MI patients as compared to the control group. Significance of this reduction is not clear at this time.

Background: There is high prevalence of obesity and smoking in Saudi population. Both are major risk factors for developing hypertension (HT) and MI. Associations between hypertension, MI and ABO blood groups have been shown but they are inconsistent. To date no such studies have been done in Saudi Arabia to determine association between ABO blood groups and prevalence of smoking, hypertension and MI in Saudi female patients.Methods: 432 control females were randomly selected and distribution of ABO and Rh antigens was statistically analyzed and compared with 78 smokers, 219 hypertensive and 311 MI female patients admitted to King Khalid hospital between the periods of August 2017 to May 2018.Results: Among controls 3.2% were smokers, 7.6% hypertensive and 13.2% diabetics. Among hypertensive 7.8% were smokers and 46.6% were diabetics. Likewise we also found statistically significant increase in prevalence of smoking (9.9%) and diabetes (48.2%) in MI female patients. Additionally about half of MI patients (49.8%) were hypertensive. 85.9% controls were Rh+ and 14.1% were Rh-. Rh+ subjects were significantly higher in hypertensive and MI patients also. O+ was most prevalent and AB+ was least prevalent in all groups.Conclusions: Statistically there was no difference between distributions of, B-, B+, AB-, AB+ blood groups, however there was high prevalence of A blood group in hypertensive (31.4%) and female MI patients (31.2%) as compared to A blood group among controls (24.8%). Distribution of O blood group wassignificantly lower in hypertensive (42%) and MI patients (41.5%) as compared to controls (53.1%).