Primary open angle glaucoma in northern Nigeria: stage at presentation and acceptance of treatment

Abstract

BackgroundTo determine the stage of primary open angle glaucoma at presentation at a tertiary eye unit, to assess patient’s knowledge of glaucoma and acceptance and subsequent adherence to treatment.MethodInformation collected prospectively on new glaucoma patients aged 30 or more years included distance from residence and what they knew about glaucoma and its treatment. Treatment offered took account of disease severity and socioeconomic factors. Reasons for not accepting surgery were recorded. At follow up intraocular pressure (IOP) was measured and adherence to medication assessed verbally. Four categories of severity were defined based on visual acuity and visual fields defects in the worse eye.Results131 patients were recruited (mean age 52.8 years; 62 % male). Most attended because of symptoms (70 %). Mean IOP in affected eyes was 31.9+/-SD 12.4 and mean vertical cup:disc ratio was 0.8. 99 eyes (47 %) had a visual acuity of light perception or worse. Risk factors for advanced/end-stage disease were age >50 years, living >10 km from the hospital, some awareness of glaucoma, not being literate, being unemployed and presenting with symptoms. In multivariable analysis older age and poor knowledge of glaucoma remained independent risk factors. 75 were offered trabeculectomy: five agreed but only one underwent surgery. Reasons for rejecting surgery were fear (37 %), preferred medical treatment (27 %) and cost (15 %). 32/85 (24 %) participants started on topical medication attended follow up. 72 % reported excellent compliance but only 56 % of glaucomatous eyes had IOPs less than 21mmHg.ConclusionsTo prevent glaucoma blindness strategies are required which promote earlier detection, with counselling to promote acceptance of and adherence to treatment.

Opportunistic Screening for Glaucoma Amongst Glaucoma Patients’ First Degree Relatives who Accompanied them to Glaucoma Clinic

“…Patients with POAG need to be identified early through adequate screening (5,16) . In Nigeria, many studies (17,18,19) have indicated that patients with glaucoma present late to the hospital. Therefore, ceasing every opportunity to screen those at higher risk will help in identifying those with the disease early and treat them accordingly.…”

“…In that study, 81% of those aware of family history of Glaucoma reported that they had gone for screening for the disease. In Nigeria, poor knowledge of glaucoma has been identified as a major factor associated with late presentation of glaucoma patients (18,19) . A robust population-based study in Nigeria showed that the prevalence of glaucoma was 5.02% with 86% of it being the open angle (4) .…”

Improving services for glaucoma care in Nigeria: implications for policy and programmes to achieve universal health coverage

“…The following definitions were used to estimate the number affected by level of severity, using the most affected eye: severe/advanced glaucoma—VA <3/60, vertical cup:disc ratio (VCDR) >0.8 and central visual field (CVF) of <10°; moderate glaucoma—any level of VA with VCDR >0.7 and CVF of 10–20°; early/mild glaucoma—any glaucomatous visual field defect and VCDR ≥0.7. Blind/end-stage glaucoma was defined as VA <3/60 in the better eye with a VCDR of 1.0 17. There are estimated to be 5900 (56%) adults per million population with severe/advanced disease, often blind in one eye and/or with severe visual impairment in the other eye, 2100 (20%) moderate cases, 400 (4%) early cases and a further 2100 (20%) are blind in both eyes.…”

“…These include low rates of early detection and diagnosis,17 lack of specialist equipment and treatment options, lack of specialist glaucoma clinics and care pathways, poor compliance with treatment and follow-up,9 the high cost of accessing care and treatment costs18 and lack of awareness and public knowledge about glaucoma compounded by socioeconomic deprivation 10. The number of eye health workers in Nigeria, including ophthalmologists and optometrists, falls short of WHO recommendations 19 20.…”

“…One-off interventions are recommended in Africa, one being primary trabeculectomy with antimetabolites or β-irradiation, with a suggested ‘glaucoma surgical rate’ of 800 glaucoma surgeries per million population per year 22. Indeed, skilful trabeculectomy with a joint care plan and adequate follow-up may be a good option but acceptance of surgery can be very low 9 17. Laser therapy seems a safe and acceptable alternative, which reduces costs to patients, as an inpatient stay is not required.…”