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

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. 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. 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. 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.