A population-based study conducted in Olmsted County, Minn., confirms that the incidence of cataract surgery has steadily increased over 32 years, reaching record levels in 2011. Additionally, second-eye surgery is performed sooner and more frequently. Between 2005 and 2011, 60 percent of residents had second-eye cataract surgery within three months of first-eye cataract surgery, more than double the 28 percent rate recorded between 1998 and 2004.
A research team led by Jay C. Erie, M.D., used Rochester Epidemiology Project (REP) databases to identify all incident cataract surgeries — 8,012 procedures in 5,725 persons — in Olmsted County, Minn., residents between Jan. 1, 2005, and Dec. 31, 2011.
"We intended to estimate incidence rates of cataract surgery in a defined population and determine longitudinal cataract surgery patterns," says Dr. Erie. The team calculated age- and sex-specific incidence rates and merged that information with previous REP incidence data from 1980 to 2004 to assess long-term temporal trends.
Age-related cataract affects more than 22 million Americans. That number may rise to 30 million by 2020. "The resulting cataract treatment burden will likely influence the distribution of U.S. health care funding," says Dr. Erie. "Understanding temporal cataract surgery incidence rates and the factors that influence them will help us develop effective policies and procedures to manage costs and to ensure access to care."
Inclusion and impact
With approval from the Mayo Clinic and Olmsted Medical Center institutional review boards, all incident primary cataract surgeries performed on all Olmsted County residents during the study period were retrospectively identified. Thirteen ophthalmologists were available to provide cataract surgery to county residents during the study period.
Current data were merged with previous REP data for 1980 to 2004 to create a 32-year, population-based, longitudinal cataract surgery registry. In the extended study period, cataract surgery was higher among women and increased with age. Overall incident cataract surgery rates continued to steadily increase with no indication of leveling off.
Reasons for the rising cataract surgery incidence rates include:
- Improved access to surgery is available for patients with new cataract or previously unmet needs.
- The number of cataract surgeons increased 27 percent since 2002, and Mayo Clinic shifted from hospital-based surgery to an outpatient surgery center in 2003.
- Adoption of widening indications for surgery, which creates a larger surgical population and an increase in second-eye surgery. Second-eye surgery is associated with higher patient satisfaction and improved quality of life, but earlier second-eye surgery is also associated with increased surgery rates.
"Although the characteristics of Olmsted County residents are similar to the state of Minnesota and the Upper Midwest, residents are less ethnically diverse, more highly educated and wealthier than the overall U.S. population," says Dr. Erie. "Results from numerous previous REP studies, however, have generally been consistent with national data."
The updated cataract surgery registry will be used to estimate changes in annual demand for cataract surgery, plan future health care spending and ensure adequate access to appropriate cataract treatment.
For more information
Dr. Erie presented his results at the annual American Society of Cataract and Refractive Surgery and American Society of Ophthalmic Administrators symposium and congress in April 2013.