A randomised, controlled study of the effects of aerobic exercise and dietary fish on coagulation and fibrinolytic factors in type 2 diabetics

Type 2 diabetes is associated with disturbances in coagulation and fibrinol ysis. Prospective studies show that increased tissue plasminogen activator (tPA) antigen increases the risk of cardiovascular mortality. The present s tudy examined the hypothesis that combining a regime of moderate aerobic ex ercise with one daily fish meal as part of a low-fat diet (30% total energy ) would improve coagulation and fibrinolytic factors in dyslipidaemic type 2 diabetic patients. In a randomised, controlled, 8-week trial, 55 sedentar y type 2 diabetic subjects with serum triglycerides >1.8 mmol/l and/or HDL- C <1.0 mmol/l were randomly assigned to a low-fat diet (30% daily energy in take) with or without one fish meal daily (3.6 g omega 3 fatty acids/day) a nd further randomized to a moderate (55-65% (V) over dot O-2max ) or light (heart rate <100 bpm) exercise program. Plasma levels of fibrinogen, coagul ation factor VIIc, tPA and plasminogen activator inhibitor (PAI-1) antigen were measured before and after intervention. In the 49 subjects who complet ed the study, the fish diet alone, moderate exercise alone and the combinat ion of fish and moderate exercise all led to significant reductions in tPA antigen concentrations (-2.1 ng/ml, p = 0.02, -1.9 ng/ml, p = 0.03, -2.0 ng /ml, p = 0.01, respectively) compared to controls. In multivariate regressi on, changes in fasting blood glucose (positively) and erythrocyte omega 3 f atty acid composition (inversely) were independent predictors of the change in tPA antigen. The fish diet alone contributed to a significant rise in c oagulation factor We compared to controls (4.9%, p = 0.02), which was preve nted by moderate exercise. No significant effects on PAI-1 antigen and fibr inogen were seen. In view of recent epidemiological findings, the reduction in tPA antigen with both fish and moderate exercise in these dyslipidaemic type 2 diabetic patients could reflect a reduced thrombotic potential and decreased cardiovascular risk. Furthermore, a small, albeit significant, in crease in coagulation factor VIIc associated with fish can be prevented by a concomitant programme of moderate exercise.