Abstract
Purpose :
The role of a secondary inflammatory disease on age-related macular degeneration (AMD) progression is still largely unknown. We investigated the association between AMD and rheumatoid arthritis (RA) using MarketScan® data for patients 65 years and older on Medicare with supplemental insurance coverage.
Methods :
Subjects with at least 2 records of ICD-9 diagnosis codes of RA and insurance coverage for a minimum of 365 days were extracted from MarketScan® for 2010. A control group of subjects without RA was selected among the remaining population. Subjects with a diagnosis of cancer or late effects of stroke were excluded. Records from a Baseline period of 6 months were used to construct measures of 27 chronic conditions treated in outpatient settings using the Elixhouser method and measures of hospital admissions and comorbid conditions recorded in the hospital discharge records using the Charlson comorbidity score. Subjects with a diagnosis code of AMD during the Baseline period were also excluded to increase the likelihood of measuring incident AMD cases during follow-up study time. The RA and control group subjects were matched on 35 Baseline variables using propensity scoring with a greedy algorithm. Medical care data for matched subjects were examined for 4.5 years after the Baseline period, and records with an ICD-9 diagnosis code of AMD were extracted (2010-2014). Multivariable logistic regression, controlling for subject characteristics and time in study was used to compare Odds of having an AMD diagnosis between the RA subjects and matched controls. Survival analysis was used to examine differences in days until first AMD diagnosis between RA patients and controls.
Results :
Risk of a new diagnosis of AMD was found to be elevated in patients with RA (OR of 2.08 [95% CI 1.98-2.18]). This risk was slightly elevated in female patients with an odds ratio of 1.11 (1.05-1.17) when compared to the male population. In addition, the time to first AMD diagnosis was significantly shorter for subjects with RA than that observed for controls (p<0.0001).
Conclusions :
Our analysis provides further support of an association between the presence of RA and an increased diagnosis of AMD. These data might support the hypothesis that synergistic effects of systemic inflammation, such as those generated by RA and local inflammation in the eye may increase the risk for AMD development.
This is an abstract that was submitted for the 2017 ARVO Annual Meeting, held in Baltimore, MD, May 7-11, 2017.