Okinawa is well known as the leading area for longevity and people in Okinawan islands are known to have the lowest risk of ischemic heart disease (IHD). Reasons for this particularly low IHD risk among Okinawans are unclear. Since most studies about IHD risk factors have been based on population in Western nations and their findings may not apply to Okinawans, a hospital-based case-control study was conducted at a community hospital in Okinawa.
To assess the relative importance of risk factors for IHD among the people in Okinawa, 205 Okinawan patients who had acute myocardial infarction (AMI) and 205 age-and-gender matched control were analyzed.
The most important risk factor of AMI was current cigarette smoking. History of diabetes mellitus and hypertension were also independent risk factors. Of lipid profile, lower concentrations of serum high density lipoprotein (HDL) cholesterol and higher serum triglyceride (TG) were independent risk factors while, in contrary, serum low density lipoprotein cholesterol and uric acid were not associated with AMI.
To effectively prevent IHD among Okinawans, smoking cessation and treatment of hypertension, diabetes, and dyslipidemia (high TG and low HDL) are important. However, lowering LDL cholesterol may be not.