Aims: To profile the distribution of people screened across the diagnostic grades for retinopathy and to further investigate the relationship between retinopathy and other clinical signs such as maculopathy, HbA1c, and visual acuity.
Methods: The study used all records of first screening visits by 11,977 people from 2002-2005 in a longitudinal cohort design.
Results: The majority of people (68%) enrolled in the screening programme had no retinopathy in either eye; 20% had minimal NPDR; 8% had mild NPDR; 2% had moderate NPDR; and 0.5% had severe NPDR. Only 28 people (0.2%) had proliferative retinopathy. Maculopathy was detected in 1429 cases (12.3%). There was a significant relationship between the progression of retinopathy and incidence of maculopathy (Chi-squared=3642.77; p<0.01). The mean log(MAR) value for best visual acuity in the eye with worse retinopathy showed there was an overall reduction in visual acuity as retinopathy progressed. Higher levels of HbA1c were associated with more advanced progression of NPDR (Chi-squared= 389.266; p<0.01) and the presence of maculopathy (Chi-squared= 147.056; p<0.01). New Zealand Maori were under-represented in the screened population while Pacific Island (PI) people appeared to be well represented.
Conclusion: The Wellington regional retinal screening programme for people with diabetes managed by the Wellington Independent Practice Association (WIPA) provides a quality service accessed by a high proportion of the people in the region having diabetes (92%). Two key strengths of the programme are its routine collection of comprehensive information and the links between general practice, optometry, and ophthalmology.