Cost analysis of early trabeculectomy versus conventional management in primary open angle glaucoma

The financial cost of managing primary open angle glaucoma by trabeculectomy at diagnosis was compared with the cost of a more conventional sequence of medical therapy followed by trabeculectomy only in unsuccessful cases. Costs were estimated at 1989 prices for 104 patients studied in a prospective randomised multicentre trial which had been running for eight years. Separate estimates were made for operative costs, inpatient costs, and outpatient costs including visual field tests and medications. Values were adjusted to allow for the observed mortality rate within the group. Conventionally managed patients with bilateral glaucoma required an average total expenditure of 2,570 pounds for the eight year period, compared with 2,560 pounds for those treated by early surgery. In both groups expenditure was greatest in the first year of care, and declined over the eight years. Although early surgery incurred a higher cost within the first year, in subsequent years the conventionally managed group was consistently more expensive and so overall costs were similar. Inpatient care was the most expensive item in both groups (62% of total cost in conventional management, and 77% with early surgery). Our current practice is to admit patients for a shorter period than the average of 7.6 days at the time of this trial. We have therefore produced cost estimates based on a shorter inpatient stay of one and four days per operation, and in both cases early surgery becomes the less expensive strategy. The results have been presented in a form that allows substitution of regional and temporal variations in costs and medical practice.