Co-Prevalence of Alzheimer's Disease and Age-Related Macular Degeneration Established by Histopathologic Diagnosis.

BACKGROUND

Previous epidemiologic studies have suggested an association between AMD and AD, and several therapeutic agents are being developed based on this principle. However, prior studies have provided conflicting results due in part to their reliance on clinical diagnoses that are not based on gold-standard histopathology.

OBJECTIVE

To use histopathologic standards for diagnosis in order to determine the co-prevalence of AD among patients with and without AMD.

METHODS

This is a cross-sectional study of 157 autopsy ocular specimens from patients with and without AMD that were greater than 75 years of age at death. Sarks staging was used to document the severity of AMD, and Braak and Braak staging was used to assess the severity of AD in corresponding brain specimens. The prevalence of AD within different severities of AMD was determined using univariable and multivariable logistic regression.

RESULTS

58% of autopsy eyes had AMD. The prevalence of AD was lower in AMD subjects (63%) compared to non-AMD subjects (73%), even when grouped by severity (all p > 0.15). The likelihood of AD was significantly less in AMD subjects, even after adjusting for age and sex in multivariable analysis (OR 0.47, p = 0.049).

CONCLUSION

Histopathologic diagnoses fail to support an increase in prevalence of AD among subjects with AMD, even when disease severity is considered.