There were few reports regarding the relatively lower incidence of myocardial infarction in patients with pulmonary emphysema. To give a better understanding of this problem, we performed the present study. The results were as follows.
1. Fifty eight patients with chronic obstructive pulmonary diseases from 19 to 91 years of age were divided on the basis of the criteria proposed by Fishman into three groups, i. e., predominant emphysema, predominant bronchitis and other pulmonary diseases. And 191 healthy adults from 30 to 79 years of age were selected as a control. The serum cholesterol, triglycerides, phospholipids and lipoproteins were measured in every subjects from three groups. In majority of the patients, HDL-cholesterol subfractions and apoproteins were also determined.
2. There were no differences with levels of serum cholesterol and phospholipids among three groups, but serum triglycerides of the emphysema group was significantly lower than that of bronchitis group (111±6 vs 159±19mg; p<0.02).
3. The serum HDL-C concentration was significantly higher in the group of emphysema than in the group of bronchitis and in the control group (55.7±3.8 vs 39.8±3.7, 47.0±1.1mg; p<0.001, 0.01). The emphysema group also showed significantly higher level of HDL-PL than that of the normal control group (118±7.4 vs 98.7±1.6mg; p<0.001).
4. The ratio of HDL2-C/HDL-C was higher in the emphysema group (72.1±2.0%) than in other groups. And serum Apo A-I level was higher in the emphysema group (136.2±5.4mg) as compared to the bronchitis group (118.4±3mg).
In conclusion, we found that patients with pulmonary emphysema have an increased level of HDL-C and HDL-PL. We believe that this finding may explain in part the decreased incidence of myocardial infarction among these patients. And mechanism of HDL-C increase in the emphysema patients was discussed from the view point of pulmonary surfactant metabolism.
