Estimated Prevalence of Age-Related Macular Degeneration Remains High in US

A new analysis suggested that approximately 20 million individuals were living with some form of age-related macular degeneration (AMD) in the United States in 2019.

The estimation indicated a higher prevalence of early-stage AMD and a similar prevalence of late-stage AMD compared with earlier studies. Substantial variations in the prevalence of both early- and late-stage AMD at the state and county level were reported after accounting for differences in demographics.

A comparison of race and ethnicity groups showed the estimated gender- and age-standardized rates of early-stage AMD were lower for non-Hispanic Black individuals, while gender- and age-standardized rates of late-stage AMD were lower for non-Hispanic Black and Hispanic individuals.

“Primary contributions of this work as compared with earlier estimates include updating US population demographics, the inclusion of individuals in group quarters, inclusion of newer population-based study data, and estimation of state and county estimates,” wrote study author David B. Rein, PhD, NORC at the University of Chicago.

Historically, AMD is a leading cause of blindness in the US and is considered the leading cause of blindness among White individuals. Rein and colleagues set out to determine estimates of AMD in the US, noting its prevalence has not been estimated in the US since a decade prior and early-stage AMD prevalence estimates tend to be inconsistently measured.

The investigators used bayesian meta-regression methods to estimate the national, state, and county prevalence of early- and late-stage AMD by age group, gender, race and ethnicity for the year 2019. Data sources included abstracted published results of population-based studies (PBS), the National Health and Nutrition Examination Survey (NHANES) from 2005 to 2008, Medicate 2018 fee-for-service (FFS) claims, and 2019 American Community Survey (ACS) data.

The main outcomes of the analysis were the prevalence of early- and late-stage manifestations of AMD. Early-stage AMD was defined as retinal pigment epithelium abnormalities or the presence of drusen ≥125 µm in diameter in either eye, while late-stage AMD was defined as choroidal neovascularization and/or geographic atrophy in either eye.

Investigators estimated there were 18.34 million individuals 40 years and older living with early-stage AMD (95% uncertainty interval [UI], 15.30 - 22.03), corresponding to a crude prevalence rate of 11.64% (95% UI, 9.71 - 13.98).

The gender- and age-standardized rate for non-Hispanic Black individuals was lower at 7.16% (95% UI, 5.44 - 9.24) than for non-Hispanic White individuals and Hospanic individuals.

Moreover, investigators reported an estimate of 1.49 million people aged 40 years and older living with late-stage AMD (95% UI, 0.97 to 2.15), corresponding to a crude prevalence rate of 0.94% (95% UI, 0.62 to 1.36).

Data show the gender- and age-standardized rate of late AMD for non-Hispanic White individuals 40 years and older was 1.03% (95% UI, 0.65 - 1.52), while the rates were 0.38% (95% UI, 0.16 - 0.79) for Hispanic individuals and 0.65% (95% UI, 0.37 to 1.03) for non-Hispanic Black individuals.

As NHANES data was last collected in 2008 and PBS data before that, Rein stressed that the data used are older and may have limited the findings of the study. Newer data may improve these estimates, he added.

“Until such data are available, this research can be used for surveillance and public health planning purposes,” Rein said.

The study, “Prevalence of Age-Related Macular Degeneration in the US in 2019,” was published in JAMA Ophthalmology.