(i) To estimate changes in apoB and apoB/apoA-I, reflecting the balance between atherogenic and anti-atherogenic lipoprotein particles, by exercise training and compare with changes in LDL-C and TC/HDL-C ratio, and (ii) To compare strengths of relationships between physical fitness and various lipoprotein variables.
The study was a 1-year open randomized trial comprising 219 healthy middle-aged subjects aged 40-49 years who were allocated to exercise or no exercise, dietary advice or no advice in a 2 x 2 factorial design. This study includes 188 men who completed the trial, 45 to diet, 48 to exercise, 58 to diet + exercise and 37 to control.
Exercise; supervised endurance exercise three times a week. Diet; reduce weight, increase intake of fish and reduce total fat intake.
One-year change in apoB and apoB/apoA-I ratio.
Exercisers decreased their ApoB and ApoB/ApoA-I values significantly compared to non-exercisers. LDL-C was not, but LDL-C/HDL-C was marginally but statistically significantly reduced by exercise. One-year change in ApoB and ApoB/ApoA-I correlated more strongly to 1-year changes in physical fitness than LDL-C or LDL-C/HDL-C. Adjusting for changes in LDL-C or LDL-C/HDL-C did not influence the correlation between changes in fitness and ApoB or ApoB/ApoA-I. However, adjusting for changes in ApoB or ApoB/ApoA-I wiped out the correlation between change in fitness and LDL-C or LDL-C/HDL-C. Relationships weakened when adjusting for changes in waist circumference, but Apo B or ApoB/ApoA-I still correlated significantly to changes in fitness.
Physical exercise reduced the atherogenic burden as experienced by the reduction in apoB or apoB/apoA-I levels, but not by LDL-C in healthy middle-aged men. Possibly, regular physical activity might increase the LDL-C particle size, thereby making LDL less atherogenic. Monitoring of apolipoproteins rather than the cholesterol moiety of lipoproteins might improve the assessment of lipoprotein changes after exercise training.
The association between serum cholesterol and blood pressure (BP) has been studied in 16 525 men. The study reveals that these Oslo men in their forties present with a serum cholesterol value which is on average 0.71 mmol/l (27.4 mg/100 ml) higher at diastolic BP greater than 110 mmHg than at BP less than 70 mmHg. According to earlier studies in Oslo, this cholesterol difference alone imparts a 10-year myocardial infarction morbidity difference of 25--30%. These findings might be of practical importance for epidemiological studies and for preventive measures against the two factors. The influence of other variables on the association between blood pressure and cholesterol has been studied in a multivariate analysis. Of these variables, only body mass index and serum triglycerides significantly influence the relationship between blood pressure and cholesterol, whereas age, cigarette smoking, non-fasting blood sugar, season, socioeconomic status, and physical activity at work and leisure do not influence the correlation.
In the recently published CARE-study, 4,159 patients aged 21-75 years were included and randomised to treatment with pravastatin 40 mg once daily or placebo 3-20 months following a myocardial infarction. Inclusion criteria were a total cholesterol
Coronary heart-disease (C.H.D.) had been reviewed as a "manager's disease". However, deaths from C.H.D. are now said to be more common in groups from the lower social classes than in those of higher socioeconomic status. We have examined wheather these differences in C.H.D. mortality can be explained by differences in the conventional risk factors for C.H.D.
Coronary risk factors (CRF) have been recorded for nearly 15 000 men aged between 40 and 49 living in Oslo in 1972. These data are matched with the 1970 census data for Norway so as to analyse CRF within various occupational groups. A fairly good agreement between mortality statistics for Norway and CRF was found in many occupations. For instance, persons in pedagogical work have low total mortality rates consistent with their low coronary risk factors. Taxi and busdrivers, on the other hand, have been reported to have mortality rates from lung cancer and coronary heart disease consistent with their high smoking prevalence, serum triglycerides, and cholesterol levels.