Genetically Determined Plasma Lipid Levels and Risk of Diabetic Retinopathy: A Mendelian Randomization Study.

PubMed ID: 28951389

Author(s): Sobrin L, Chong YH, Fan Q, Gan A, Stanwyck LK, Kaidonis G, Craig JE, Kim J, Liao WL, Huang YC, Lee WJ, Hung YJ, Guo X, Hai Y, Ipp E, Pollack S, Hancock H, Price A, Penman A, Mitchell P, Liew G, Smith AV, Gudnason V, Tan G, Klein BEK, Kuo J, Li X, Christiansen MW, Psaty BM, Sandow K; Asian Genetic Epidemiology Network Consortium, Jensen RA, Klein R, Cotch MF, Wang JJ, Jia Y, Chen CJ, Chen YI, Rotter JI, Tsai FJ, Hanis CL, Burdon KP, Wong TY, Cheng CY. Genetically determined plasma lipid levels and risk of diabetic retinopathy: a Mendelian randomization study. Diabetes. 2017 Dec;66(12):3130-3141. doi: 10.2337/db17-0398. Epub 2017 Sep 26. PMID 28951389

Journal: Diabetes, Volume 66, Issue 12, Dec 2017

Results from observational studies examining dyslipidemia as a risk factor for diabetic retinopathy (DR) have been inconsistent. We evaluated the causal relationship between plasma lipids and DR using a Mendelian randomization approach. We pooled genome-wide association studies summary statistics from 18 studies for two DR phenotypes: any DR (N = 2,969 case and 4,096 control subjects) and severe DR (N = 1,277 case and 3,980 control subjects). Previously identified lipid-associated single nucleotide polymorphisms served as instrumental variables. Meta-analysis to combine the Mendelian randomization estimates from different cohorts was conducted. There was no statistically significant change in odds ratios of having any DR or severe DR for any of the lipid fractions in the primary analysis that used single nucleotide polymorphisms that did not have a pleiotropic effect on another lipid fraction. Similarly, there was no significant association in the Caucasian and Chinese subgroup analyses. This study did not show evidence of a causal role of the four lipid fractions on DR. However, the study had limited power to detect odds ratios less than 1.23 per SD in genetically induced increase in plasma lipid levels, thus we cannot exclude that causal relationships with more modest effect sizes exist.