What percentage of patients presenting for routine eye examinations require referral for secondary care? A study of referrals from optometrists to ophthalmologists.

BACKGROUND: The aim was to investigate the percentage of asymptomatic patients presenting for routine optometric eye examinations that have pathology or pathology-related risk factors warranting referral for ophthalmological consultation. METHODS: This was a retrospective, cohort case study and the inclusion criteria for participants included: (i) the patient presented for routine optometric eye care during a specified period of time; (ii) the patient was found to have pathology (or showed enough risk of pathology) resulting in referral to an ophthalmologist; and (iii) a referral report was received from the consulting ophthalmologist stating the diagnosis and the treatment plan. The data set was further reviewed to indicate presenting symptoms and patient age. Adult patients, ages 20 to 64 years, were reviewed separately; this age group is not covered by provincial health services for routine eye care in Nova Scotia. Files were obtained from two clinics through an electronic charting program. A database was created that included date of referral, clinical reasons for the referral, diagnosis and treatment plan. Clinical reasons for referral were extracted from the referral letters and reports and sorted into six disease categories: age-related macular degeneration, cataract, glaucoma, diabetic retinopathy, retinopathy and 'other'. RESULTS: The overall referral rate for the combined data set was nine per cent for all ages; 2.4 per cent of the overall patients were asymptomatic. There was a similar number of asymptomatic patients referred in the adult (20 to 64 years) age group compared to all ages (2.5 per cent). CONCLUSION: A significant number of patients that present for routine eye examinations without any symptoms indicative of ocular disease are subsequently found to have a degree of pathology or risk thereof requiring referral for ophthalmological consultation. These referrals occur for adults under 64 years as much as for all patients of all ages.