Dyslipidaemia pattern and prevalence among type 2 diabetes mellitus patients on lipid-lowering therapy at a tertiary hospital in central South Africa

Abstract

Background: Atherosclerotic cardiovascular disease (ASCVD) is a major cause of death worldwide. A large number of deaths due to ASCVD occurs among people with diabetes mellitus (DM). One of the important modifiable risk factors associated with ASCVD is dyslipidaemia and its prevalence is not known in central South Africa (SA). This study aimed to determine the pattern and prevalence of dyslipidaemia among type 2 diabetes mellitus (T2DM) patients on lipid-lowering therapy. Methods: This descriptive, retrospective study of patients’ records was conducted at Universitas Academic Hospital in Bloemfontein, SA. The study population included 143 consecutive T2DM patients of any age that attended the Diabetes Clinic from 1 January to 31 March 2019. The patients had to be on lipid-lowering therapy for a minimum duration of 3 months. Data were sourced from the clinic files and included the patient’s lipid profile, anthropometric and demographic data. Dyslipidaemia was defined using the 2018 SA dyslipidaemia guidelines. Results: The median age of the participants was 63 years (interquartile range [IQR] 52–71 years). The majority of the participants were female (n = 92; 64.3 %). The median duration since the DM diagnosis was 18 years (IQR 13–23 years). The prevalence of dyslipidaemia was 86.7 % (n = 124). Combined dyslipidaemia, namely either triglycerides (TG) + low-density lipoprotein cholesterol (LDL), high-density lipoprotein cholesterol (HDL) + TG or HDL + LDL, was the most common pattern (n = 51; 42.5 %) largely due to raised TG + LDL contributing 37.2 % (n = 19) to this pattern. The second and third most common patterns were isolated (either LDL, HDL or TG) and mixed dyslipidaemia (TG + HDL + LDL) at 40.8 % (n = 49) and 16.7 % (n = 20), respectively. The most frequent lipid abnormality (n = 84; 70.0 %) was LDL of ≥ 1.8 mmol/L. Of the 140 participants on statin therapy, only 5 % were on high-intensity therapy. Conclusions: A high prevalence of dyslipidaemia among DM patients was observed, despite the use of lipid-lowering therapy in this small observational study. Our findings highlight the need to better educate healthcare providers regarding the intensification of lipid-lowering therapy, along with improved strategies to address poor glycaemic control and other modifiable lifestyle factors.