Table 2.
Level of evidence for the association of G6PD deficiency with CVD.
| Study | Patients (n) | Effect and proposed mechanism | Association# | Evidence∗ | Reference |
|---|---|---|---|---|---|
| Long et al. (1967) | 1,465 | G6PD protective for CVD. OR 0.41 (95% CI 0.24–0.70) “statin-like” effect | Weak | Level 3 | [7] |
| Cocco et al. (1998) | 1,756 | G6PD protective for ischemic heart disease. SMR 0.28 (0.10–0.62) Impaired NO metabolism |
Moderate | Level 3 | [8] |
| Pinna et al. (2007) | 1,344 | G6PD protective for retinal vein occlusion. OR 0.39 (95% CI 0.24–0.64) “Statin-like” effect |
Moderate | Level 3 | [98]. |
| Pinna et al. (2008) | 420 | G6PD protective for nonarteritic anterior ischemic optic neuropathy. OR 0.40 (95% CI 0.17–0.94) “statin-like” effect and impaired NO metabolism | Weak | Level 3 | [99] |
| Meloni et al. (2008) | 738 | G6PD protective. OR 0.58 (95% CI 0.38–0.89) “Statin-like” effect and reduced ROS production by NADPH oxidase downregulation |
Moderate | Level 2 | [10] |
| Seyedian et al. (2016) | 1484 | G6PD protective for coronary artery disease. OR 0.87 (95% CI 0.56-1.35). “Statin-like effect” | Weak | Level 2 | [102] |
| Thomas et al. (2018) | 17,338 | G6PD detrimental. OR 1.39 (95% CI 1.04–1.87). Impaired glutathione and NO metabolism | Strong | Level 2 | [15] |
| Pes et al. (2019) | 9,604 | G6PD detrimental. OR 1.71 (95% CI 1.17–2.49). Multiple mechanisms including impaired inflammation, glutathione, and NO metabolism | Moderate | Level 2 | [17] |
| Ou et al. (2020) | 1,251 | G6PD detrimental. OR 1.53 (95% CI 1.09–2.17) Impaired vascular redox state |
Strong | Level 3 | [18] |
#The strength of association was reported based on effect size (OR, HR, frequency, P value and so on). ∗The level of evidence was ranked according to Hadorn [180] in descending order: (level 1) meta-analyses of randomized studies, (level 2) a single study, (level 3) nonrandomized studies, (level 4) retrospective studies, and (level 5) a series of cases without controls.