REFERENCE INTERVALS AND DECISION LIMITS FOR PLASMA-LIPIDS AND LIPOPROTEINS - A PRACTICAL EVALUATION OF CURRENT RECOMMENDATIONS

As part of a longitudinal study-the Kristianstad Survey-we measured pl asma cholesterol, HDL- and LDL-cholesterol, triglycerides and lipoprot ein (a) in a reference group consisting of 203 men and women aged 20-8 0, randomly sampled from a well-defined area in the southernmost part of Sweden. The selection of reference individuals and the collection o f specimens for assay of the constituents were performed in accordance with current recommendations. The results were subjected to statistic al analyses both with and without application of exclusion criteria. A pplication of the theoretical exclusion criteria resulted in the exclu sion of 22% of the participants; however, this procedure had a remarka bly weak impact on the results: the mean values and the standard devia tions were almost unaltered. The mean (standard deviation) for cholest erol was 5.9 (1.3) mmol l-1, for HDL-C 1.1 (0.3) mmol l-1, and for LDL -C 4.3 (1.2) mmol l-1. Women had higher values than men. Plasma trigly cerides were positively skewed; their median and Q3-Q1-values were 1.0 and 0.5 mmol l-1 respectively, men higher than women. There was an in crease with age for cholesterol and LDL-C in both sexes and for trigly cerides in women. The steepest increase of cholesterol values with age in women coincided with menopause, which gave a more clear-cut separa tion between high and low cholesterol values than did any age limit.