Exposure assessments of cadmium and lead with age-related eye disease: A systematic review and meta-analysis

Background: Age-related eye diseases, such as macular degeneration, cataracts, and glaucoma, are significant causes of vision loss in older adults. Emerging evidence suggests that environmental exposure to heavy metals, particularly Cadmium and lead, may play an essential role in the onset and progression of these conditions. Methods: This systematic review and meta-analysis aimed to evaluate the association between Cadmium and lead exposure and the risk of age-related eye diseases. A comprehensive literature search was conducted across multiple databases, including PubMed, Embase, Scopus, and Web of Science, covering studies published up to July 2024. The review included observational studies on the relationship between Cadmium or lead exposure and specific eye conditions. Data extraction and quality assessment were performed independently by two reviewers. The meta-analysis utilized a random effects model to analyze cadmium and lead levels in patient and control groups, with subgroup analyses based on the type of eye disease and study design. Results: The results revealed a significant association between cadmium exposure and an increased risk of eye diseases, particularly cataracts and glaucoma. Lead exposure was also linked to a higher risk of cataracts and macular degeneration. The study found substantial heterogeneity among the included studies, highlighting the variability in exposure assessment and population characteristics. Conclusions: Despite these variations, the findings underscore the importance of addressing environmental exposures to toxic metals as potential risk factors for age-related eye diseases. Further research is needed to clarify the underlying mechanisms and to develop targeted interventions for reducing these risks.