Population-Based Prevalence and 5-Year Change of Soft Drusen, Pseudodrusen, and Pachydrusen in a Japanese Population

Miki Sato-Akushichi; Reiko Kinouchi; Satoshi Ishiko; Kazuomi Hanada; Hiroki Hayashi; Daiki Mikami; Shinji Ono; Yasuo Yanagi

doi:10.1016/j.xops.2021.100081

Population-Based Prevalence and 5-Year Change of Soft Drusen, Pseudodrusen, and Pachydrusen in a Japanese Population

Ophthalmol Sci. 2021 Nov 17;1(4):100081. doi: 10.1016/j.xops.2021.100081. eCollection 2021 Dec.

Authors

Miki Sato-Akushichi¹, Reiko Kinouchi^{1

2}, Satoshi Ishiko^{1

2}, Kazuomi Hanada², Hiroki Hayashi², Daiki Mikami², Shinji Ono¹, Yasuo Yanagi¹

Affiliations

¹ Department of Ophthalmology, Asahikawa Medical University, Hokkaido, Japan.
² Medicine and Engineering Combined Research Institute, Asahikawa Medical University, Asahikawa, Hokkaido, Japan.

Abstract

Purpose: To elucidate the prevalence of soft drusen, pseudodrusen, and pachydrusen and their 5-year changes in a Japanese population.

Design: Longitudinal population-based cohort study conducted from 2013 through 2017.

Participants: Residents 40 years of age or older.

Methods: Nonmydriatic color fundus photographs were used to grade drusen subtypes and retinal pigment epithelium (RPE) abnormalities according to the Three Continent Age-Related Macular Degeneration Consortium. The 5-year changes of each drusen were investigated.

Main outcome measures: The prevalence of each drusen subtype and the 5-year changes of each drusen.

Results: Among 1731 participants, 1660 participants had gradable photographs that were assessed. The age-adjusted prevalence of soft drusen, pachydrusen, and pseudodrusen was 4.3% (95% confidence interval [CI], 3.2%-5.8%), 7.7% (95% CI, 6.2%-9.7%), and 2.8% (95% CI, 1.7%-4.2%), respectively. Pachydrusen accounted for 82.0% (n = 50) of the extramacular drusen (n = 61). Pigment abnormalities were seen in 28.3% and 8.3% of eyes with soft drusen and pachydrusen, respectively (P < 0.0001). Longitudinal changes were investigated in 1444 participants with follow-up examinations, which showed an increase in size in 8.3% and 3.7% and regression in 1.7% and 5.5% for eyes with soft drusen and pachydrusen, respectively. No participants demonstrated RPE atrophy after pachydrusen regression.

Conclusions: The prevalence of pachydrusen was higher than that of soft drusen and pseudodrusen combined. Pachydrusen may regress over time and typically is not associated with RPE atrophy as detected using color fundus photographs.

Keywords: AMD, age-related macular degeneration; CFP, color fundus photograph; CI, confidence interval; Drusen subtypes; GA, geographic atrophy; Longitudinal changes; OCT, optical coherene tomography; Pachydrusen; Population-based cohort study; RPE, retinal pigment epithelium.