The Effect of Continuity of Care and Provider Volume on Late Presentation of Glaucoma: A Nested Case-Control Study

Precis: Glaucoma late presentation is not associated with continuity of care. However, it is associated with frequency of physician visits and physician volume. Purpose: Late presentation of glaucoma often causes blindness. Continuity of care (COC) has been the central element in primary care. We investigated whether COC, frequency of visits to ophthalmology departments, and provider experience can reduce late presentation. Methods: We conducted a nested case-control study on patients aged above 20 years with confirmed glaucoma diagnosis. Claims data from the Taiwan's National Health Insurance Research Database during 2007 to 2016 were linked to the Disability Registry (n=231,330) to identify patients with glaucoma late presentation. Physician experience was proxied using service volume. Logistic regression was estimated using matched samples. Results: A total of 111 patients satisfied the definition of late presentation. Patients with a low frequency of visits had lower odds of being in the late-presentation group (odds ratio=0.39, 95% confidence interval=0.18-0.81). COC index did not statistically affect late presentation. Old age and lower socioeconomic status were significantly associated with higher odds of late presentation. A statistically significant negative association was observed between physician volume and odds of late presentation. Conclusion: Late presentation for glaucoma can be reduced by promoting more frequent physician visits. However, enhancement from the provider-side, such as spreading awareness and offering routine tests, also play essential role in reducing late presentation.