Health system dynamics analysis of eyecare services in Trinidad and Tobago and progress towards Vision 2020 Goals

Awareness of Common Ocular Conditions Among Trinidad Population: A Cross-Sectional Pilot Study

Background and Aims

Cataracts, glaucoma, diabetic retinopathy (DR), uncorrected refractive error (URE), and corneal anomalies are some of the leading causes of blindness and visual impairment (VI). Awareness of these ocular conditions and their consequences is crucial for early detection and management to prevent blindness. The study is aimed to assess the awareness of common ocular conditions among adults in Trinidad.

Methods

A cross-sectional study of Trinidad and Tobago (T & T) adults was conducted to determine their awareness of common ocular conditions. Data were collected face-to-face using a self-administered questionnaire and systematic random sampling. Awareness was defined as whether the respondent had ever heard of the ocular conditions. Knowledge, on the other hand, was assessed based on the respondent's understanding of various aspects of each condition, including its symptoms, risk factors, and management strategies.

Result

A total of 230 individuals aged 18 to 83 years participated in this study, with 146 (63.5%) being female. Majority of participants (69.1%) were under 30 years of age, and 63% had attained tertiary education. Cataracts had the highest awareness rate (n = 226, 98.3%), followed by glaucoma (n = 184, 80%). A significant association was found between age and awareness of diabetic retinopathy (DR) (p = 0.01), while sex was significantly associated with awareness of all ocular conditions, except for DR, glaucoma, and refractive errors (RE) (all p > 0.05). Level of education was significantly associated with awareness of DR (p = 0.02), and occupation was significantly associated with awareness of all ocular conditions, except cataracts and glaucoma (p > 0.05). The primary sources of information about ocular conditions were family, friends, and relatives (n = 199, 87%).

Conclusion

The level of awareness of the common ocular conditions among the T & T populations was comparable with the global findings. There is a need to increase awareness of DR and RE among the population to reduce the burden caused by these conditions.

The societal economic impact of vision impairment in adults 40 years and above: findings from the National Eye Survey of Trinidad and Tobago

BACKGROUND

Understanding and mitigating the societal economic impact of vision impairment (VI) is important for achieving the Sustainable Development Goals.

AIM

To estimate the prevalent societal economic impact of presenting VI in Trinidad and Tobago using bottom-up cost and utilisation data from the 2014 National Eye Survey of Trinidad and Tobago.

METHODS

We took a societal perspective to combine comprehensive, individual-level cost and utilisation data, with population-based prevalence estimates for VI, and additional data from a contemporaneous national eyecare system survey. We included direct (medical and non-medical) and indirect (productivity loss) costs, and intangible losses in total cost estimates, presented in 2014 Trinidad & Tobago (TT) dollars and UK sterling equivalent. We considered but excluded transfer payments and dead weight losses. Sensitivity analyses explored impact on total cost of parameter uncertainty and assumptions.

RESULTS

Individual utilisation and cost data were available for 65.5% (n = 2792/4263) and 59.0% (n = 2516/4263) eligible participants aged ≥40 years, respectively. Participant mean age was 58.4(SD 11.8, range 40-103) years, 56.3% were female. We estimated total societal cost of VI in 2014 at UK£365,650,241 (TT$3,842,324,655), equivalent to £675 per capita (population ≥40 years). Loss of wellbeing accounted for 73.3%. Excluding this, the economic cost was UK£97,547,222 (TT$1,025,045,399), of which indirect costs accounted for 70.5%, followed by direct medical costs (17.9%), and direct non-medical costs (11.6%).

CONCLUSION

This study provides a comprehensive estimate of the economic impact of vision loss in a Caribbean country, and highlights the extent to which affected individuals and their families bear the societal economic cost of vision impairment.

Sight impairment registration in Trinidad: trend in causes and population coverage in comparison to the National Eye Survey of Trinidad and Tobago

BACKGROUND

Little was known about the population coverage and causes of sight impairment (SI) registration within the Caribbean, or the extent to which register studies offer insights into population eye health.

METHODS

We compared causes of SI registration in the Trinidad and Tobago Blind Welfare Association (TTBWA) register with findings from the 2014 National Eye Survey of Trinidad and Tobago (NESTT), and estimated registration coverage. Cross-sectional validation studies of registered clients included interviews, visual function and cause ascertainment in July 2013, and interviews and visual function in July 2016.

RESULTS

The TTBWA register included 863 people (all ages, 48.1%(n = 415) male) registered between 1951 and 2015. The NESTT identified 1.1%(75/7158) people aged ≥5years eligible for partial or severe SI registration, of whom 49.3%(n = 37) were male. Registration coverage was approximately 7% of the eligible population of Trinidad. Nevertheless, there was close agreement in the causes of SI comparing the register and population-representative survey. Glaucoma was the leading cause in both the register (26.1%,n = 225) and population-based survey (26.1%, 18/69 adults), followed by cataract and diabetic retinopathy. In the validation studies combined, 62.6%(93/151) clients had severe SI, 28.5%(43/151) had partial SI and 9.9%(15/151) did not meet SI eligibility criteria. SI was potentially avoidable in at least 58%(n = 36/62) adults and 50%(n = 7/14) children.

CONCLUSION

We report very low register coverage of the SI population, but close agreement in causes of SI to a contemporaneous national population-based eye survey, half of which resulted from preventable or treatable eye disease.

An Economic Analysis for the Use of Artificial Intelligence in Screening for Diabetic Retinopathy in Trinidad and Tobago

This is a systematic review of 25 publications on the topics of the prevalence and cost of diabetic retinopathy (DR) in Trinidad and Tobago, the cost of traditional methods of screening for DR, and the use and cost of artificial intelligence (AI) in screening for DR. Analysis of these publications was used to identify and make estimates for how resources allocated to ophthalmology in public health systems in Trinidad and Tobago can be more efficiently utilized by employing AI in diagnosing treatable DR. DR screening was found to be an effective method of detecting the disease. Screening was found to be a universally cost-effective method of disease prevention and for altering the natural history of the disease in the spectrum of low-middle to high-income economies, such as Rwanda, Thailand, China, South Korea, and Singapore. AI and deep learning systems were found to be clinically superior to, or as effective as, human graders in areas where they were deployed, indicating that the systems are clinically safe. They have been shown to improve access to diabetic retinal screening, improve compliance with screening appointments, and prove to be cost-effective, especially in rural areas. Trinidad and Tobago, which is estimated to be disproportionately more affected by the burden of DR when projected out to the mid-21st century, stands to save as much as US$60 million annually from the implementation of an AI-based system to screen for DR versus conventional manual grading.

Scope of optometry practice in Trinidad and Tobago: A cross-sectional study

Background and Aim

To report the scope of optometry practice in Trinidad and Tobago to identify areas that need improvement.

Methods

A cross-sectional study of optometrists in Trinidad and Tobago was conducted using a validated self-structured questionnaire. Data obtained was exported to the Statistical Package for Social Sciences. Descriptive analysis and Pearson χ 2 were used to summarize the demographic data and determine associations, respectively.

Result

A total of 63 optometrists participated in the study. Majority of them were females (69.8%, n = 44), Christians (65.1%), East Indians (47.6%), and 30 years and below (66.7%). Most (87%) of them utilized routine optometric equipment in their clinical practice including autorefractors, retinoscopes, direct ophthalmoscopes, lensometers, phoropters, slit lamp biomicroscopes, trial lens boxes, and visual acuity chart projectors. A few of them have noncontact tonometer (4.8%), Volk lenses (1.6%), and perform color vision tests (1.6%). Fewer (12.7%, n = 8) practitioners provided low-vision services. The use of pharmaceutical agents was prevalent among the participants (55.6%). Additionally, the provision of contact lenses was the most frequently practiced service among the participants (85.7%, n = 54). A significant association was observed between the provision of low-vision services and sex (p = 0.03).

Conclusion

The scope of optometry practice in Trinidad and Tobago is in accordance with the basic guidelines set out by the World Council of Optometry but there is need to get more involved in the provision of low vision and other specialty services.

The development and application of a two-step surveillance process for Healthy China Initiative based on wide coverage interagency data

BACKGROUND

Healthy China is a nationwide health strategy aiming at improving health from diverse dimensions, and strengthening high-quality assessment is essential for its stimulation. However, there is limited evidence in the surveillance of the actual performance of the initiative at regional levels. This study innovatively proposes a two-step surveillance process which comprehensively monitors Healthy China Initiative based on regional realities, thus provides guidance for policymaking.

METHODS

A flexible indicator system was firstly developed basing on Delphi survey and focus group discussions. And then the Analysis Hierarchical Process and the TOPSIS method were used to determine the weights of indicators and calculate comprehensive indexes as the surveillance outcomes. A pilot study was conducted in a typical area in China to verify the applicability of the process.

RESULTS

Following the surveillance process and basing on the implementation of Healthy China Initiative in the target region, an indicator system comprised of 5 domains and 23 indicators with weights was first developed specifically for the pilot area. Then 1848 interagency data of the study area were collected from 8 provincial institutions/departments to calculate the indexes and ranks of the five domains which were health level, healthy living, disease prevention and control, health service, and healthy environment. The outcomes showed that Healthy China Initiative in the pilot area had been constantly improved since the strategy proposed, while there were still issues to be tackled such as the deficient monitoring mechanisms and unevenly development progress.

CONCLUSIONS

This study proposed a pragmatic surveillance process with indicators which could be tailored for specific context of target regions and produce meaningful surveillance outcomes to inform decision-making for policymakers, and also provided a theoretical foundation as well as empirical evidence for further health strategies and plannings assessment studies.

A retrospective study of causes of visual impairment and use of low vision devices in the low vision clinic in Trinidad and Tobago

PURPOSE

To determine the causes of visual impairment and the use of low vision devices in patients attending the low vision clinic in Trinidad and Tobago.

METHODS

A retrospective study of the 222 patients attending the low vision clinic at the University of the West Indies, St Augustine Campus was conducted. The presenting visual acuity, causes of low vision and blindness, and prescribed low vision devices were recorded and analysed to determine the major causes of visual impairment and improvement in visual acuity with low vision aids.

RESULTS

Out of the total 222 participants, 66.66% (n = 148) had low vision while the rest (33.33%, n = 74) were legally blind. Glaucoma was the major cause of low vision (31.08%) and blindness (28.38%) followed by diabetic retinopathy (20.94%, low vision and 20.27%, blindness). A total of 193 low vision devices were prescribed, 79.79% (n = 154) near devices and 20.20% (n = 39) distance devices. The low vision devices were effective in improving both near visual acuity (120 participants reading 1M or 2M) and distance visual acuity (VA better than 3/60).

CONCLUSION

The major causes of vision impairment in Trinidad and Tobago were glaucoma and diabetic retinopathy and low vision devices are effective in improving visual acuity. A comprehensive approach to dealing with the causes of low vision and low vision services are required to mitigate the burden of visual impairment in the country.

A Review of Advancements and Evidence Gaps in Diabetic Retinopathy Screening Models

Diabetic retinopathy (DR) is a microvascular complication of diabetes with a prevalence of ~35%, and is one of the leading causes of visual impairment in people of working age in most developed countries. The earliest stage of DR, non-proliferative DR (NPDR), may progress to sight-threatening DR (STDR). Thus, early detection of DR and active regular screening of patients with diabetes are necessary for earlier intervention to prevent sight loss. While some countries offer systematic DR screening, most nations are reliant on opportunistic screening or do not offer any screening owing to limited healthcare resources and infrastructure. Currently, retinal imaging approaches for DR screening include those with and without mydriasis, imaging in single or multiple fields, and the use of conventional or ultra-wide-field imaging. Advances in telescreening and automated detection facilitate screening in previously hard-to-reach communities. Despite the heterogeneity in approaches to fit local needs, an evidence base must be created for each model to inform practice. In this review, we appraise different aspects of DR screening, including technological advances, identify evidence gaps, and propose several studies to improve DR screening globally, with a view to identifying patients with moderate-to-severe NPDR who would benefit if a convenient treatment option to delay progression to STDR became available.

National Eye Survey of Trinidad and Tobago (NESTT): prevalence, causes and risk factors for presenting vision impairment in adults over 40 years

AIM

To estimate the prevalence, causes and risk factors for presenting distance and near vision impairment (VI) in Trinidad and Tobago.

METHODS

This is a national, population-based survey using multistage, cluster random sampling in 120 clusters with probability-proportionate-to-size methods. Stage 1 included standardised, community-based measurement of visual acuity. Stage 2 invited all 4263 people aged ≥40 years for comprehensive clinic-based assessment. The Moorfields Eye Hospital Reading Centre graded fundus photographs and optical coherence tomography images independently.

RESULTS

The response rates were 84.2% (n=3589) (stage 1) and 65.4% (n=2790) (stage 2), including 97.1% with VI. The mean age was 57.2 (SD 11.9) years, 54.5% were female, 42.6% were of African descent and 39.0% were of South Asian descent. 11.88% (95% CI 10.88 to 12.97, n=468) had distance VI (logarithm of the minimum angle of resolution [logMAR] >0.30), including blindness (logMAR >1.30) in 0.73% (95% CI 0.48 to 0.97, n=31), after adjustment for study design, non-response, age, sex and municipality. The leading causes of blindness included glaucoma (31.7%, 95% CI 18.7 to 44.8), cataract (28.8%, 95% CI 12.6 to 45.1) and diabetic retinopathy (19.1%, 95% CI 4.2 to 34.0). The leading cause of distance VI was uncorrected refractive error (47.4%, 95% CI 43.4 to 51.3). Potentially avoidable VI accounted for 86.1% (95% CI 82.88 to 88.81), an estimated 176 323 cases in the national population aged ≥40 years. 22.3% (95% CI 20.7 to 23.8, n=695) had uncorrected near VI (logMAR >0.30 at 40 cm with distance acuity <0.30). Significant independent associations with distance VI included increasing age, diagnosed diabetes and unemployment. Significant independent associations with near VI included male sex, no health insurance and unemployment.

CONCLUSIONS

Trinidad and Tobago's burden of avoidable VI exceeds that of other high-income countries. Population and health system priorities are identified to help close the gap.