Oxidative stress-elevated high gamma glutamyl transferase levels, and aging, intake of tropical food plants, migration and visual disability in Central Africans

Abstract

Aim: To investigate the independent pathogenic role of high serum gamma-glutamyl transferase (GGT) levels, sociodemographic data, dietary and environmental risk factors for visual disability (VD).

Methods: This was a case-control study, run in 200 black Congolese patients managed in Saint Joseph Hospital Ophthalmology Division from Kinshasa town. Logistic regression model was used to identify determinants of VD (n=58) among sex, age, cigarette smoking, alcohol abuse, rural-urban migration, education levels, aging ≥60 years, intake of red Beans, Safou fruit and Taro leaves, lipid profile, residence, socioeconomic status, and GGT.

Results: After adjusting for confounding factors, we identified migration (OR=3.7 95% CI: 1.2-11.3; P=0.023), low education level (OR=3.1 95% CI 1.1-8.5; P=0.026), no intake of Safou fruit (OR=34.2 95% CI 11.5-102; P<0.0001), age ≥ 60 years (OR=2.5 95% CI 1.01-6.5; P=0.049), and serum GGT ≥10 U/L (OR=3.6 95% CI 1.3-9.6; P=0.012) as the significant and independent determinants of VD.

Conclusion: VD appears as a major public health problem in Central Africa to be prevented or delayed by control of migration, lifestyle changes, antioxidant supplements, appropriate diet, nutrition education, and blocking of oxidative stress.

Keywords: aging; intake of tropical food plants; oxidative stress; serum gamma-glutamyl transferase; vision loss.

Figure 1. Taro leaves (Colocasia Antiquorum).

Figure 2. Different species of Safou prune (Dacryodes edulis)

A: D.edulis var.paricarpa.; B: D.edulis var.edulis.

Figure 3. Red beans.

Figure 4. ROC curve of GGT to discriminate presence of visual disability from absence of visual disability: AUC = 0.717 95% CI 0.642-0.793. Standard Error = 0.038; P<0.0001.