Cataract surgery rates in Ontario, Canada, from 1992 to 2004: more surgeries with fewer ophthalmologists

BACKGROUND: To evaluate trends in cataract surgeries in Ontario between 1992 and 2004. METHODS: A retrospective analysis of the number of cataract surgeries performed in Ontario from April 1992 to March 2005. The estimated prevalence of cataract and cataract surgeries per 1000 persons at risk was calculated. RESULTS: The number of cataract surgeries in Ontario increased from 44,943 in 1992 to 109,506 in 2004 (143.6%, 12.08% annual increase). The number of cataract surgeries per 1000 patients at risk of cataract increased from 64.6 in 1992 to 115.65 in 2004 (79%, 4.97% increase per year). This rate was strongly positively correlated with time and with the increase in the Ontario population (r = 0.920 and r = 0.922, respectively; p < 0.001). The number of ophthalmologists increased by 5.3% from 1992 to 1997 and then decreased by 2.9% by 2004. This change was not correlated with the cataract surgery rates (r = 0.475; p = 0.10). However, the number of ophthalmologists per million population decreased by 13.4% between 1992 and 2004. This number had a statistically negative correlation with cataract surgery rates (r = -0.757; p < 0.01). INTERPRETATION: There has been a significant increase in the number of cataract surgeries in Ontario despite a decrease in the number of ophthalmologists per million population.