Diabetic Retinopathy in Kenya: assessment of services and interventions to improve access

Abstract

The majority of the estimated 425 million people living with diabetes (PLWD) reside in low and middle-income countries. An estimated 35% of PLWD have diabetic retinopathy (DR) and 10% have vision threatening retinopathy (VTDR) requiring urgent treatment. There is a high unmet need for DR services in many of these countries, which highlights the need to strengthen health systems. The purpose of this PhD is to provide evidence on the factors and interventions for promoting access and utilisation of services for DR. The study setting is Kenya, which has adopted Universal Health Coverage (UHC) as a target for 2030. The specific objectives were: i) To synthesise the literature on the magnitude, needs and priorities for diabetic retinopathy services; ii)To conduct an assessment of the health system for PLWD and diabetic retinopathy in Kenya; iii) To use the evidence from the literature and evidence from the health system assessment as a platform for health system strengthening; and iv) To develop and test an intervention through a randomized clinical trial to improve uptake of eye care services for PLWD in Kenya. Methods: The first objective was achieved through a literature review. For the second objective, a health system assessment for diabetes and DR was conducted, based on the World Health Organization’s framework for health systems building blocks and the tracer condition approach. For the third objective, as part of health system strengthening, national guidelines for DR and a short online course for health care workers were developed. For the fourth objective, using the evidence from the health system assessment, we designed and implemented a two arm (1:1) pragmatic cluster randomized controlled trial to test whether a peer-supporter-led package of interventions can increase uptake of DR screening among members of diabetes support groups who have never had screening. The primary outcome measure was attendance at DR screening in the 14 clusters and 734 participants followed up over six months. Results: A review of the literature on the epidemiology and interventions for diabetes and DR, identified that the key priorities of health systems in reducing the incidence of DR-related blindness are: (1) control of diabetes (2) early detection of DR and (3) appropriate treatment of DR. However, most of the available evidence is from highincome countries. The health system assessment for diabetes and DR in Kenya identified a high unmet need for DR screening, and uptake of screening was the bottleneck to entry to DR services. The barriers were lack of referral and inadequate knowledge of diabetes eye health. The lack of clinical guidelines and inadequate opportunities for continuous professional development limit the availability of DR services. To address this barrier, national clinical guidelines were developed through a process of adaptation from generic guidelines. The scope of the guidelines is screening, diagnosis, treatment and follow-up for DR. In addition, an online training course on the control of DR has been developed using the theories of adult learning and instructional design. The results of the cluster-randomized trial indicate that the peer-led interventions are acceptable and reach the population most vulnerable to DR. One in two of the participants in the intervention arm compared to one in ten in the control arm attended DR screening. We also found that most of the effect occurs early—within the first month of the intervention. Conclusions: This thesis provides evidence about how national DR guidelines and online training programmes for health workers can be developed to strengthen health systems and improve eye services for PLWD. The thesis also provides evidence that the uptake of DR screening by PLWD can be significantly increased through a community based intervention utilising diabetes support groups and peer-supporters. This can lead to earlier diagnosis of DR and the prevention of blindness.