Abstract
Purpose :
To describe the ocular and systemic associations of a 6-year change in drusen volume derived from automated OCT measurements in a population-based cohort.
Methods :
A prospective, observational, population-based study of eye diseases in Chinese adults aged 40 years and older living in Singapore included a protocol-based assessment to capture medical and ocular history, color fundus photo (CFP)-based AMD grading, and automated drusen volume assessment with SD-OCT using built-in software (Cirrus OCT advanced RPE analysis software). Eyes that had adequate quality SD-OCT scans at baseline and 6-year follow-up, with no other retinal pathology except AMD, were included in this study.
Results :
A total of 2130 eyes of 1305 patients (mean age 54.7±7.2 years; 50.6% female) had baseline and 6-year follow-up SD-OCT. A total of 144 (6.8%), 1672 (78.5%) and 314 (14.7%) eyes had drusen volumes that decreased, remained stable, and increased respectively (median volume change:-0.009, 0 and 0.006mm3). There was a significant trend of increasing drusen volume associated with the presence of AMD, drusen and maximum drusen size measured on CFP at baseline. After 6 years, 52 eyes showed progression of AMD as graded on CFP, of these only the 3 eyes that progressed from no AMD to late AMD showed a increase in drusen volume (median: 0.071 mm3), the other eyes (49 and 1 eyes progressed from no to early and early to late AMD, respectively) had no change in drusen volume. Multivariable analysis showed that when compared to eyes where drusen volume was unchanged, drusen volume decrease was significantly associated with older age (OR=1.30; P<0.001), smoking (OR=2.21; P=0.001) and chronic kidney disease (OR=3.40; P=0.008), while drusen volume increase was associated with older age (OR=1.36; P<0.001) and hypertension (OR=1.43; P=0.016).
Conclusions :
About 20% of eyes had changes in drusen volume over a 6-year period, as measured on consecutive SD-OCT scans. Increased drusen volume is associated with any AMD and larger drusen area graded on baseline CFP. The progression from no AMD to late AMD was rare but associated with drusen volume increase. Various systemic factors associated with long-term changes in drusen volume, such as age, smoking, hypertension and chronic kidney disease may provide new insights into the pathogenesis of AMD.
This is a 2020 ARVO Annual Meeting abstract.