Trends in cataract surgery practice

Current trends advocate a presenting visual acuity (PVA) of 6/12 or less with cataract as a cause of visual impairment as the visual acuity threshold to consider cataract surgery indication.[1] With change in the cutoff for cataract surgery indication, a shift in trends in cataract practice to offer earlier cataract surgery to patients is becoming prevalent. The southern part of Asia seems to be harboring the leading figures in visual impairment (VI) due to cataract and refractive error with the highest age-standardized prevalence of blindness and moderate to severe VI from 1990 to 2020 in populations aged ≥50 years.[2] Hence, there is a pressing need to look at the assessment indicators of cataract-related blindness/VI to better strategize the plan of action toward its management. Cataract surgical coverage (CSC) had been used as an indicator to monitor cataract surgical services with CSC indicative of the measure of people in a defined population with operated cataract as a proportion of those having operable plus operated cataracts. This measure can be calculated for the various levels of visual acuity and was employed as a key output under the Rapid Assessment of Avoidable Blindness (RAAB) surveys. As CSC did not take into account of quality of cataract surgery, the definition of effective cataract surgical coverage (eCSC) gained heightened importance. eCSC measures the number of people in a population who have undergone cataract surgery with a good outcome as a proportion of all those who were operated on or required surgery and serves as one of the key indicators for assessing the progress toward the set global target[3–5] and defines regions requiring enhanced cataract surgical services. The 74th World Health Assembly had recommended a global target for eCSC of a 30% increase by 2030.[6] Low- and middle-income countries (LMICs) including the five countries in South Asia (Bangladesh, Bhutan, India, Nepal, and Pakistan) need more uniform and robust population-based data which can help to better interpret the trends in cataract surgical progress assessment at the national, subnational, or regional level. A recent analysis of the RAAB survey data conducted in 31 districts of India during 2015–2019 among persons aged 50+ years to evaluate eCSC and CSC[7] noted the age-sex standardized and weighed eCSC in India to be 36.7%, and CSC 57.3% with a relative quality gap in cataract surgery being 36.0%. The eCSC in males was observed to be higher at 38.0% as compared to that of females of 35.6%. eCSC was 31.0% in illiterate participants as compared to that of 59.7% in those who were class-10 educated. eCSC was poor in rural areas, older patients, and eastern or northeastern regions of India. The eCSC in regional areas of India is noted to be lower than the CSC indicative of the fact that there is scope for improving the quality of cataract surgical services in these regions.[8–11] Similar findings are noticeable in other countries such as China and Malaysia as well.[12,13] Higher-income countries follow a higher visual acuity threshold for preoperative visual acuity for cataract surgery, which contributes to better postoperative visual outcomes.[14] Preoperative visual acuity largely remains the determinant parameter for seeking cataract surgery in LMICs with poorer preoperative acuity being the mandate for most to seek intervention. This perhaps also contributes to the lower eCSC values despite an improved CSC. Besides this, the cataract surgery cost incurred by the patient tends to largely define the need for surgery as well. The role of healthcare expenditures management in terms of third-party insurance coverage seems to be changing this scenario in low-income groups as well. In recent times, better benefits of cashless and lower self-bearing cost measures available to the patients seem to be facilitating an earlier approach to cataract surgery. However, LMIC ophthalmic health care policies to strategize on enhancing eCSC need to work on the variables for subpopulations such as females, lower socioeconomic groups, and older individuals, who face a greater challenge of access barriers for cataract surgery. Studies that optimally collate population-level data that can delineate temporal patterns in postoperative outcomes or costs of cataract surgery in India, and in LMICs, can thus largely help to contribute in the walk toward a better ocular health society. The recent retrospective analysis in South India on 12-year data (from 2012 to 2023) relating to patient demographics, preoperative vision, postoperative outcomes, and cataract surgery costs showed changing trends in cataract surgery indications, outcomes, and costs.[14] There was an increase in preoperative uncorrected visual acuity (UCVA) with females having poorer UCVA, better postoperative visual acuity, manual small incision cataract surgery faring better than phacoemulsification, an increase in paying for cataract surgery cost, and an increase in cataract surgeries supported by an insurance sector. The gender disparity in females seeking surgery later and being opted for lower-cost surgeries prevailed. This gender discrimination was also noted over a decade ago in another study from South India.[15] While good-quality surgeries to tackle cataract visual impairment are achievable in rural surgical care centers as well, there remains a wider gap between CSC and eCSC in almost all regions. Overall, there seems to a healthy trend of leaning toward earlier cataract surgery with better preoperative visual acuity given the advancement in cataract microsurgical techniques, devices, and equipment which can serve to be a pointer toward decreased frequency of surgical complications, better visual outcomes, and the earlier recovery of useful vision. While this is achievable in urban centers, the need to establish the uniformity in cataract surgical care standards and outcome in rural surgical centers is imperative in developing nations which will be reflected by a lesser gap between CSC and eCSC rates. With the current scenario of eCSC varying widely between countries, better rates with higher income level, higher in men, there needs to be focus on strategies to improve eCSC in countries with lower-resource scenarios, with improved access and availabilty of quality cataract surgery to the underserved populations can help to reach the pursuit of 30% increase in eCSC by 2030.