Interpretation of Traditional Lipid Profile: A Reference Interval of a Nigerian Population

Abstract

Background: The interpretative goal in dyslipidemia is based on a well-established laboratory reference interval in a low economic resource country. However, such establishment by the standard direct method is quite expensive and cumbersome, which makes the dependence on the Western reference values with a different reference individual of a different lifestyle and socio-economic setting. This has led to over or under-diagnosis of dyslipidemia and its burden. The aim of this study was to establish local multivariate references and compare them with the currently used western values.

Results: The overall mean age of the participants was 52.3±13.7 years, while the males' and females' ages were 53.3±14.7 and 51.7±13.7 years, respectively. The sex ratio was 1:1.4. The established reference intervals were triglyceride (0.6-2.0mmol/L), total cholesterol (3.1-5.9mmol/L, low-density lipoprotein cholesterol (1.7-4.1mmol/L) and high-density lipoprotein cholesterol of 0.7-1.5mmol/L respectively. The values for triglyceride and HDL-C were not affected by age and sex; the total cholesterol and the LDL-C levels increased with age until the 6th decade, with a subsequent decrease after.

Conclusion: Interpreting the lipid profile result with caution, given the observed upper reference limits in age and sex stratification, is important to identify CHD risk and avoid over diagnosis of dyslipidemia. Age and sex stratification should be considered in the interpretation.