Determinants of Pentacam-derived lens density in age-related cataract: the role of ocular dominance and lifestyle factors

BACKGROUND: Pentacam-derived lens density provides an objective measure of lens opacity in cataract. However, the roles of ocular dominance and lifestyle-related factors in lens density variation remain unclear. This study investigated the association of ocular dominance and lifestyle factors with lens density in patients with age-related cataract. METHODS: This cross-sectional study included 52 patients with age-related cataract recruited from Peking University People's Hospital between May 15 and June 30, 2026. Ocular dominance, Pentacam-derived lens density, pupil parameters, visual acuity, and lifestyle factors were assessed. Paired tests, Spearman correlation, and linear regression analyses were used for statistical analysis. RESULTS: The mean age of participants was 66.5 ± 7.8 years. Dominant eyes exhibited significantly higher Pentacam lens density than non-dominant eyes (P = 0.024). Dominant eyes also showed smaller pupil area (P = 0.024) and smaller pupil diameter (P = 0.019) than non-dominant eyes. Best-corrected visual acuity (BCVA) was significantly lower in dominant eyes than in non-dominant eyes (P = 0.007). Dynamic pupil variability did not differ significantly between eyes (P = 0.104). Greater interocular differences in lens density were significantly associated with greater interocular differences in BCVA (r = - 0.403, P = 0.003). In multivariable regression analysis, dominant-eye BCVA was associated with dominant-eye pupil area after adjustment (β = -7.314, P = 0.017). In multivariable linear regression models adjusted for age, sex, and available lifestyle variables, smoking (β = 15.304, P = 0.025), alcohol drinking (β = 12.955, P = 0.012), and reading or using a phone with lights off (β = 18.869, P < 0.001) were associated with higher dominant-eye lens density. CONCLUSIONS: Ocular dominance was associated with lens density asymmetry in patients with age-related cataract. Higher dominant-eye lens density was related to worse dominant-eye visual acuity relative to the non-dominant eye. Smoking, alcohol drinking, and reading or using a phone with lights off were associated with higher dominant-eye lens density after adjustment for available covariates. These findings suggest that both ocular dominance and lifestyle-related factors may be relevant to lens opacity variation, although prospective studies are needed for confirmation.