The occurrence of new coronary heart disease (CHD) in the presence of below average serum levels of lipids and lipoproteins was studied during a 4 1/2-year period of observation of 2,998 normotensive men, aged 39 to 59 years at intake into a prospective, epidemiological investigation. It was found from this study that the normotensive, middle-aged man with the fully developed type B behavior pattern was essentially immune to the development of clinical CHD if he exhibited a serum cholesterol level less than 226 mg/100 ml, a serum triglyceride level less than 126 mg/100 ml, or a serum β-/α-lipoprotein ratio less than 2.01, singly or in combination.
Rosenman RH, Friedman M, Jenkins CD, Straus R, Wurm M, Kositchek R. The Prediction of Immunity to Coronary Heart Disease. JAMA. 1966;198(11):1159-1162. doi:10.1001/jama.1966.03110240067025