Table 2.

Summary of studies on the association of apolipoproteins and cholesterol parameters with the presence of diabetic retinopathy (DR).

Author	Number of Participants	Mean Levels of Apolipoprotein Parameters	Mean Levels of Cholesterol Parameters	Outcomes Related to the Presence of DR
Sasongko et al. [14] (2011)	With DR: 129 Without DR: 95	Apo-A1 With DR: 1.4 ± 0.3 g/L Without DR: 1.5 ± 0.2 g/L Apo-B With DR: 0.9 ± 0.3 g/L Without DR: 0.8 ± 0.2 g/L Apo-B/Apo-A1 With DR: 0.7 ± 0.2 Without DR: 0.6 ± 0.2	TG With DR: 1.3 (0.9, 1.9) mmol/L Without DR: 1.3 (0.9, 1.9) mmol/L HDL With DR: 1.3 ± 0.5 mmol/L Without DR: 1.5 ± 0.4 mmol/L LDL With DR: 2.5 ± 0.9 mmol/L Without DR: 2.5 ± 0.7 mmol/L	Odds ratio (95% CI) for any DR per SD increase of: Apo-A1: 0.76 (0.59–0.98) Apo-B: 1.31 (1.02–1.68) Apo-B/Apo-A1: 1.48 (1.13–1.95) Odds ratio (95% CI) for VTDR per SD increase of: Apo-A1: 0.53 (0.38–0.76) Apo-B: 1.47 (1.10–1.96) Apo-B/Apo-A1: 1.76 (1.27–2.45)
Malaguarnera et al. [19] (2013)	With DR: 67 Without DR: 78	Apo-A1 With DR: 1.54 ± 0.18 g/L Without DR: 1.47 ± 0.20 g/L Apo-B With DR: 1.08 ± 0.21 g/L Without DR: 1.06 ± 0.19 g/L Lp(a) With DR: 56.4 ± 28.2 mg/dL Without DR: 34.1 ± 12.4 mg/dL	TG With DR: 1.67 ± 0.76 mmol/L Without DR: 1.48 ± 0.88 mmol/L HDL With DR: 1.44 ± 0.36 mmol/L Without DR: 1.36 ± 0.30 mmol/L LDL With DR: 4.19 ± 0.99 mmol/L Without DR: 3.87 ± 0.95 mmol/L	Mean difference between groups for each parameter: Apo-A1: p = 0.03 Apo-B: p = 0.55 Lp(a): p < 0.01 LDL: p = 0.05 HDL: p = 0.15 TG: p = 0.17
Aryan et al. [21] (2017)	With DR: 444 Without DR: 439	Apo-A1 With DR: 141.8 ± 28.5 mg/dL Without DR: 135.6 ± 27.9 mg/dL Apo-B With DR: 88.1 ± 27.5 mg/dL Without DR: 85.8 ± 26.2 mg/dL Lp(a) With DR: 35.9 ± 42.2 mg/dL Without DR: 31.5 ± 34.4 mg/dL Apo-B/Apo-A1 With DR: 0.63 ± 0.24 Without DR: 0.64 ± 0.24	TG With DR: 175.9 ± 82.9 mg/dL Without DR: 170.8 ± 111.0 mg/dL HDL With DR: 45.7 ± 11.8 mg/dL Without DR: 45.6 ± 12.4 mg/dL LDL With DR: 106.5 ± 34.6 mg/dL Without DR: 102.5 ± 31.4 mg/dL	Logistic regression analysis for association with DR: Lp(a): β 0.37; OR 2.8; 95% CI 0.93–8.4 (p = 0.37) Apo-A1: β 0.01; OR 1.1; 95% CI 0.41–2.9 (p = 0.34) Apo-B: β 0.20; OR 2.4; 95% CI 0.8–7.2 (p = 0.87) Apo-B/Apo-A1: β 0.56; OR 3.4; 95% CI 0.89–12.9 (p = 0.45)
Zhang et al. [25] (2018)	With DR: 315 Without DR: 708	Apo-A1 With DR: 7.3 ± 1.2 μmol/L Without DR: 7.5 ± 1.2 μmol/L Apo-CIII With DR: 6.4 ± 1.1 μmol/L Without DR: 6.2 ± 1.1 μmol/L Apo-D With DR: 3.9 ± 0.6 μmol/L Without DR: 4.0 ± 0.6 μmol/L Apo-E With DR: 1.2 ± 0.2 μmol/L Without DR: 1.1 ± 0.2 μmol/L	TG With DR: 1.3 ± 0.4 mmol/L Without DR: 1.2 ± 0.5 mmol/L HDL With DR: 1.4 ± 0.6 mmol/L Without DR: 1.5 ± 0.5 mmol/L	Cox proportional hazard analysis for DR risk: Apo-A1 ≥ 7.4: HR 0.86; 95% CI 0.70–0.99 Apo-CIII ≥ 6.3: HR 1.25; 95% CI 1.04–1.49 Apo-E ≥ 1.1: HR 1.23; 95% CI 1.03–1.47 Apo-CIII/Apo-A1 ≥ 0.9: HR 1.34; 95% CI 1.11–1.60 Apo-E/Apo-A1 ≥ 0.2: HR 1.21; 95% CI 1.01–1.46
Chung et al. [26] (2019)	Without DR: 743 With DR: 472	Apo-A1 With DR: 1.20 (1.17–1.23) g/L Without DR: 1.26 (1.24–1.29) g/L Apo-B With DR: 0.86 (0.84–0.89) g/L Without DR: 0.87 (0.85–0.90) g/L Apo-B/Apo-A1 With DR: 0.72 (0.70–0.74) Without DR: 0.75 (0.73–0.78)	TG With DR: 1.46 (1.39–1.53) mmol/L Without DR: 1.54 (1.48–1.60) mmol/L HDL With DR: 1.12 ± 0.37 mmol/L Without DR: 1.17 ± 0.35 mmol/L LDL With DR: 2.78 ± 1.01 mmol/L Without DR: 2.84 ± 1.03 mmol/L	Logistic regression analyses for DR risk: Apo-A1 OR per SD increase 0.55; 95% CI: 0.32–0.97 (p = 0.04) Apo-B OR per SD increase 1.28; 95% CI: 0.85–1.93 (p = 0.23) Apo-B/Apo-A1 OR per SD increase 2.83; 95% CI: 1.18–6.76 (p = 0.02)
Liu et al. [29] (2022)	With DR: 309 Without DR: 186	Apo-A1 With DR: 1.29 ± 0.29 mmol/L Without DR: 1.34 ± 0.41 mmol/L Apo-B With DR: 1.01 ± 0.34 mmol/L Without DR: 1.02 ± 0.26 mmol/L Apo-E With DR: 45.74 ± 20.80 mmol/L Without DR: 47.36 ± 24.96 mmol/L Lp(a) With DR: 179.12 ± 256.68 mmol/L Without DR: 141.64 ± 183.54 mmol/L	TG With DR: 1.80 ± 1.26 mmol/L Without DR: 2.24 ± 2.01 mmol/L HDL With DR: 1.25 ± 0.34 mmol/L Without DR: 1.40 ± 2.13 mmol/L LDL With DR: 2.85 ± 1.11 mmol/L Without DR: 3.00 ± 0.88 mmol/L	Logistic regression analyses for DR risk: Apo-A1 OR 1.91; 95% CI: 0.94–3.88 (p = 0.07) Apo-B OR 7.04; 95% CI: 3.37–14.70 (p < 0.001) Apo-E OR 1.06; 95% CI: 1.04–1.08 (p < 0.001) Lp(a) OR 1.00; 95% CI: 1.00–1.00 (p = 0.27)

Abbreviations: DR: diabetic retinopathy; HR: hazard ratio; OR: odds ratio; SD: standard deviation; CI: confidence interval; apo: apolipoprotein; Lp(a): lipoprotein (a); TG: triglyceride; HDL: high density lipoprotein; LDL: low density lipoprotein.