Five-year changes in macular thickness in the elderly population: A cohort study

BackgroundThe aim of this study is to determine the 5-year changes in macular thickness and related factors.MethodsData were from the second (2014) and third (2019) phases of the Shahroud Eye Cohort Study. Examinations included measurement of uncorrected and best-corrected visual acuity, non-cycloplegic autorefraction, slit-lamp biomicroscopy, and funduscopy. Participants underwent Cirrus HD-OCT 4000 (Carl Zeiss Meditec, Dublin, CA). imaging.ResultsThe 5-year changes (95% confidence interval) of central and overall macular thicknesses were - 3.48 +/- 8.16 mu (-3.92, -3.03) and - 0.79 +/- 4.06 mu (-1.03, -0.54), respectively. The median and IQR of 5-year changes in the central subfield thickness were -3 and 10, although they were 0 and 5 in the overall macular thickness, respectively. Multiple regression model showed the central macular thickness (CMT) decreased with a U-shape pattern with increasing age. The 5-year changes in CMT were significantly lower in females compared to males beta = -1.55; (-2.78, -0.32) and in smokers compared to non-smokers beta = -1.92; (-3.55, -0.28). Moreover, higher body mass index beta = -0.12; (-0.22, -0.02) and CMT at baseline beta = -0.08; (-0.10, -0.06) were significantly associated with lower CMT changes. The average 5-year changes in overall macular thickness showed a non-linear decrease with age and was significantly higher in females beta = 0.93; (0.4, 1.43). These changes were directly related to the anterior chamber depth beta = 0.87; (0.10, 1.64) in the baseline.ResultsThe 5-year changes (95% confidence interval) of central and overall macular thicknesses were - 3.48 +/- 8.16 mu (-3.92, -3.03) and - 0.79 +/- 4.06 mu (-1.03, -0.54), respectively. The median and IQR of 5-year changes in the central subfield thickness were -3 and 10, although they were 0 and 5 in the overall macular thickness, respectively. Multiple regression model showed the central macular thickness (CMT) decreased with a U-shape pattern with increasing age. The 5-year changes in CMT were significantly lower in females compared to males beta = -1.55; (-2.78, -0.32) and in smokers compared to non-smokers beta = -1.92; (-3.55, -0.28). Moreover, higher body mass index beta = -0.12; (-0.22, -0.02) and CMT at baseline beta = -0.08; (-0.10, -0.06) were significantly associated with lower CMT changes. The average 5-year changes in overall macular thickness showed a non-linear decrease with age and was significantly higher in females beta = 0.93; (0.4, 1.43). These changes were directly related to the anterior chamber depth beta = 0.87; (0.10, 1.64) in the baseline.ConclusionsThe macular thickness decreased slightly after 5 years; however, this change is not clinically significant. Demographic factors such as age and sex and refractive errors were significantly related to macular thickness changes.