Panorama de la Salud Ocular en Nampula, Mozambique

Résumé

Backgrounds: Vision is essential for the integration of the individual into the external environment, for the performance of daily activities, and for a functional social life. The appearance of ocular pathologies or alterations can cause visual impairment (VI), which in turn has a negative impact on the quality of life of the individual, his or her family, and society in general, and can cause enormous economic losses. General objective: To analyse the eye health landscape in Nampula, Mozambique. Specific objectives (SO): SO1: Determine the prevalence of VI, its causes, and associated factors in children (<18 years) and adults (≥18 years) in Nampula; SO2: Identify barriers to accessing eye health services in Nampula and associated factors; SO3: Assess the distribution and availability of human and material resources for eye health in Nampula; SO4: Assess the outcomes of cataract surgeries performed at Central Hospital of Nampula and their impact on patients' visual function (VF) and quality of life (QV). Methodology: SO1. Two parallel, descriptive, cross-sectional studies were conducted, one in children and the other in adults. The study in children was based on clinical records of visual examinations (screening) conducted during the "Mozambique I see you better" programme 2018 and 2019 edition. Public schools in five districts (Mogovolas, Malema, Rapale, Meconta and Mossuril) in Nampula province were part of the programme. During the screening, socio-demographic data were collected (district, academic level, age, gender), visual acuity (VA) test, refraction (objective and subjective) and ocular structures were examined. The prevalence of uncorrected visual impairment (UVI), presenting visual impairment (PVI) and best-corrected visual impairment (BCVI) and their causes were determined. The adult study was conducted as part of the One Student, One Family (1E1F) programme in 2019. A total of 2.750 adults (in 1,290 families) were part of the programme, from which a minimum sample of 338 individuals was determined. Participants were randomly selected and underwent eye examinations at the University Eye Health Clinic of Lurio University. The prevalence of PVI (near and distant) and the respective cause were determined. Odds ratio (OR) and adjusted odds ratio (ORa) were calculated to study the association between the dependent (PVI) and independent variables (gender, age, education, residence, family income and systemic diseases), with a 95% confidence interval. SO2. This study corresponds to the second part of the previous study (prevalence of visual impairment in adults covered by the 1E1F program), with data collected from the same sample. It was a cross-sectional, qualitative, and quantitative, community-based study, conducted in the communities covered by the 1E1F program of the Lúrio University. For this, in addition to eye examinations, interviews were conducted, based on a script to identify information on barriers to accessing eye health services, up-to-date eye examinations (as recommended by the American Optometric Association and the American Academy of Ophthalmology), and the presence of ocular symptoms. The association between dependent variables (barriers to access, current eye examinations, and presence of ocular symptoms) and independent variables (gender, age, educational level, home address, and family income) was studied by calculating the OR and adjusted OR, with a 95% confidence interval. SO3. A mixed-method study was conducted, involving document analysis and application of a structured, self- administered questionnaire to heads of Ophthalmology Departments in health units with eye health services in Nampula province. The ratio of eye health professionals per population for each group (ophthalmologists, optometrists, and ophthalmic technicians) was estimated at the provincial and district level in Nampula, taking into account the ratio recommended by the World Health Organisation (1:250,000 or 4:1 million inhabitants for ophthalmologists and optometrists, and 1:100,000 or 10:1 million inhabitants for ophthalmic technicians). The human resources balance results from the ratio between the number of existing professionals and the ideal number, where negative values express a deficit of professionals (the number of eye care professionals missing to reach the recommended ratio) and positive values express an excess of professionals (number of professionals above the recommended number). The list of eye care materials was developed taking into account the essential equipment (for refraction services, diagnosis and treatment of glaucoma, cataract, diabetic retinopathy, and trachomatous trichiasis) as determined by the International Agency for the Prevention of Blindness. SO4. A prospective, longitudinal study was conducted in the Ophthalmology Department of the Central Hospital of Nampula (CHN). The study was divided into two phases, the first phase corresponds to the translation, cultural adaptation and validation of the visual function (VF) and quality of life (QV) questionnaires of Fletcher et al, and the second phase to the evaluation of cataract surgery outcomes. Translation and cultural adaptation (Feasibility) was performed according to the criteria defined by the American Association of Orthopaedic Surgeons. Apparent and content validation, construct, criterion, internal consistency and sensitivity to change were performed with appropriate methods and indicators. VA was assessed and questionnaires (VF and QV) were administered before and after cataract surgery. The results of cataract surgeries were classified according to the World Health Organisation (WHO) criteria, which classifies as "good" when VA is above 0.4 logMAR (20/60), "borderline" when VA is between 0.5 and 1.0 logMAR (20/60 to 20/200) and "poor" when VA is below 1.0 logMAR (20/200). Results: OE1. In children, the prevalence of visual impairment without correction (UVI), presenting (PVI), and with best correction (BCVI) was found to be 18.3 %, 10.8 %, and 5.0 %, respectively. The main causes of VI were refractive error and amblyopia. The refractive error had a prevalence of 24.7 %, and the age groups 15-17 years and 18- 20 years were significantly associated with myopia (with OR: 4.9 and OR: 8.8, respectively), as well as the 11th and 12th schooling level (OR: 8.1 and OR: 10.7, respectively), and the Malema district was associated with myopia (ORa: 0.4) and hyperopia (ORa: 0.4 and OR: 0.3) as a protective factor. In adults, near and distant PVI had a prevalence of 16.3% and 21.1%, respectively, and was statistically associated with age groups 45-65 years (OR: 4.9) and >65 years (OR: 29.1), illiteracy (OR: 13.8), primary (OR: 4.8) and secondary school level (aOR: 37.5), occupation of farmer (OR: 32.8) and retired (OR: 14.3) and presence of systemic diseases (OR: 3.3). The main causes of PVI were uncorrected refractive error and cataract. SO2. Among the participants, 49.4% had eye symptoms and 41.7% did not have their eye examinations up to date. The most frequently cited barriers to accessing eye care services were hospital overcrowding (40.7%), financial difficulties (30.0%), self-medication (20.5%), traditional treatment (17.8%), and buying glasses on the street (11.6%). Lower levels of education and monthly family income and occupation of farmer were statistically associated with most of the barriers as risk factors. SO3. Nampula province has not reached the recommended ratio of eye health professionals per population in the different categories (ophthalmic technicians with 0.8 per 100,000 inhabitants; optometrists and ophthalmologists with 0.4 and 0.2 per 250,000 inhabitants, respectively). There was also an uneven distribution of eye health professionals across the province, with a higher concentration of professionals in the provincial capital (Nampula City), so that most districts did not reach the recommended ratio, presenting a negative balance. Primary and secondary level health units lacked some equipment to provide eye health services at their level. All health units have visual acuity charts, trial sets of lenses, and trial frames. However, there is a lack of equipment to provide refraction services such as retinoscopes, autorefractometers, and lensometers in primary and secondary health units. Nampula Central Hospital is the only unit equipped to offer surgical services in Nampula. SO4. The Mozambican-adapted versions of the VF and QL questionnaires showed good psychometric properties. The difference between VA, VF, and QL before and after surgery was statistically significant (p < 0.001), there was a significant improvement after surgery, and the effect size was higher in the "perception" and "mental" subscales, respectively. After surgery, 74.3% of patients had good VA, 23.5% borderline, and 2.2% had poor VA. Conclusions: The prevalence of VI in children and adults is relatively high and is mainly due to preventable or treatable causes. The population has faced several barriers in accessing eye health services, in particular overcrowding in hospitals and financial difficulties, thus, the utilization of eye health services in the urban periphery of the provincial capital has been lower than expected and is supposed to be even worse in the other districts outside the capital, as the availability of eye health human and material resources is more limited. Surgical services are centralized at the CHN level (in the capital), which compromises the coverage of cataract surgery services in Nampula province. Patients undergo cataract surgery when some aspects of their VF and QL are already severely compromised, and the outcomes of surgeries performed at CHN have not yet reached WHO recommendations regarding VA, but have a great impact on patients' VF and QL. There is a need for more intervention with regard to eye health in Nampula, especially to make eye health services available to the most vulnerable, such as low-income people, the illiterate, the retired, and farmers.