Reference Percentiles for Macular Vessel Density by OCT Angiography and Their Association with Systemic Diseases in Chinese Adults.

PURPOSE: To establish macular vessel density reference percentiles stratified by age, sex, and axial length (AL) and investigate their association with systemic diseases.

DESIGN

Community-based, cross-sectional study.

PARTICIPANTS

A total of 6879 participants aged 20-60 years were recruited from the Jidong community. Among them, 3247 healthy individuals enrolled from August 2019 to January 2023 were included in the reference sample, and 774 eligible participants recruited between May and October 2023 comprised the analysis sample.

METHODS

All participants underwent OCT angiography (OCTA). Based on reference sample, we modeled the distribution of parafoveal superficial capillary plexus (SCP) and deep capillary plexus (DCP) vessel density and derived age-, sex-, and AL-specific reference percentiles using generalized additive models for location, scale, and shape. In the analysis sample, parafoveal SCP and DCP vessel density measurements were transformed into adjusted z-scores. We then examined the associations of systemic diseases with adjusted z-scores and the likelihood of vessel density below the 25th or 10th percentile.

MAIN OUTCOME MEASURES: Reference percentiles for parafoveal SCP and DCP vessel density and their associations with systemic diseases.

RESULTS

In the reference sample (mean [standard deviation] age, 40.39 [8.47] years; 1384 [42.62%] men), we established continuous reference percentiles for parafoveal SCP and DCP vessel density stratified by age, sex, and AL. In the analysis sample (mean [standard deviation] age, 40.39 [9.72] years; 395 [51.03%] males), diabetes was associated with lower parafoveal DCP vessel density z-scores (β, -0.56; 95% confidence interval, -0.86 to -0.25; P < 0.001) after adjustment for age, sex, AL, education, current smoking, current drinking, and body mass index. Furthermore, diabetes was associated with an increased risk of reduced DCP vessel density, both at the <25th percentile and <10th percentile.

CONCLUSIONS

This study established continuous, age-, sex-, and AL-adjusted reference percentiles for parafoveal SCP and DCP vessel density in healthy Chinese adults using the Optovue OCTA device, and highlighted the association between diabetes and reduced parafoveal DCP vessel density. The reference percentiles present a promising framework for the individualized interpretation of macular vessel density, while external validation across other populations and OCTA platforms is warranted before broader clinical application.

FINANCIAL DISCLOSURES: The author has no/the authors have no proprietary or commercial interest in any materials discussed in this article.