Lipid variability and risk of microvascular complication in patients with diabetes: A Systematic Review

Background and aims: The current systematic review aimed to elucidate the effects of lipid variability on microvascular complication risk in diabetic patients. The lipid components studied were as follows: LDL, HDL, TG, Total Cholesterol, and Remnant Cholesterol. Method: We carried out a systematic search in multiple databases, including PubMed, Google Scholar, and Scopus, up to September 2022. Finally, after omitting the duplicates, 2724 studies were left, 104 related articles were extracted from the databases, and five articles were included in the study after screening the title, abstract and full text. Result: Five studies (4 cohorts and one cross-sectional) with a total population of 138664 were reviewed. These studies were done in China, Japan, Hong Kong, Taiwan, and Italy. The average age of the patients varied from 45 to 84 years. The follow-up duration of cohort studies ranged from 4 to 7 years. These studies have shown that higher LDL, HDL, and TG variability adversely affect microvascular complications, especially nephropathy and neuropathic complications. TG and LDL variability was associated with developing albuminuria and GFR decline. In another study, a lower HDL variation had a protective effect on microalbuminuria. In contrast, another study has shown no evidence of a relationship between lipid variation and microvascular complications such as retinopathy. Conclusion: The relationship between lipid variation (LDL, HDL, and TG) (adverse effects) on microvascular complications, especially nephropathy and neuropathic (and maybe not retinopathy), is proven. Physicians and health policymakers should be highly vigilant to lipid variation in a general population.