Influence of presbyopia on smartphone usage among Chinese adults: A population study.

IMPORTANCE: Presbyopia, an essentially universal, age-related loss of the ability to focus un-aided on near objects, is the world's leading cause of visual impairment. BACKGROUND: Smartphone use is widespread in China, but little is known about the prevalence, determinants and correction of difficulties with smartphone use in the setting of presbyopia. DESIGN: Cross-sectional data from a population-based longitudinal cohort study. PARTICIPANTS: A total of 1817 persons aged ≥35 years in Guangzhou, Southern China. METHODS: Participants underwent near visual acuity (NVA) testing and completed questionnaires on smartphone usage detailing knowledge of their own presbyopia status, frequency (hours/day) and subjective difficulties with use of mobile and smartphones. Presbyopia was defined as uncorrected bilateral NVA ≤6/12 with best-corrected bilateral NVA >6/12. MAIN OUTCOME MEASURES: Difficulty in smartphone use associated with uncorrected presbyopia. RESULTS: Among 1427 respondents (78.5%) undergoing examination, 1191 (83.5%) completed questionnaires (mean age 52.3 ± 11.6 years; 54.9% women). Among 451 persons (37.8%) with presbyopia owning smartphones, 290 (64.3%) reported difficulty using them. Multiple ordinal logistic regression modelling showed difficulty in smartphone use due to presbyopia was associated with higher educational level (P = .013), worse NVA (P < .001) and more time spent using smartphones (P = .002 for 1-3 hours/day). Among persons with presbyopia owning smartphones, 353 (78.0%) said they would pay >US$15 (median US$45) for innovations making smartphone use easier. CONCLUSIONS AND RELEVANCE: Difficulty in using smartphones in the presence of presbyopia is common and affected persons are willing to pay for useful solutions to the problem.

Impact of Presbyopia and Its Correction in Low- and Middle-Income Countries.

Presbyopia affects more than 1 billion people worldwide, and the number is growing rapidly due to the aging global population. Uncorrected presbyopia is the world's leading cause of vision impairment, and as with other causes. The burden falls unfairly on low- and middle-income countries (LMICs), in which rates of presbyopic correction are as low as 10%. The importance of presbyopia as a cause of vision impairment is further underscored by the fact that it strikes at the heart of the productive working years, although it can be safely and effectively treated with a pair of inexpensive glasses. To galvanize action for programs to address uncorrected presbyopia in the workplace and beyond LMICs, it is crucial to build a solid evidence base detailing the impact of presbyopia and its correction in important areas such as work productivity, activities of daily living, visual function, and quality of life. The aim of this review was to provide an up-to-date reference for program planners and policymakers seeking to build support for programs of presbyopia correction, particularly in low-resource settings.

Effect of providing near glasses on productivity among rural Indian tea workers with presbyopia (PROSPER): a randomised trial.

BACKGROUND: Presbyopia, age-related decline in near vision, is the most common cause of vision impairment globally, but no trials have assessed its workplace effects. We aimed to study the effect of near glasses on the productivity of tea workers with presbyopia. METHODS: This randomised trial was done in tea pickers aged 40 years or older in Assam, India, with unaided near visual acuity (NVA) lower than 6/12 in both eyes, correctable to 6/7·5 with near glasses; unaided distance vision 6/7·5 or greater; and no eye disease. Participants were randomly assigned (1:1) to receive free glasses optimising NVA at working distance (cost including delivery US$10·20 per person), either immediately (intervention group) or at closeout (control group). Participants were stratified by age, sex, and productivity. The primary outcome (investigator-masked) was the difference between groups in the change in mean daily weight of tea picked (productivity), between the 4-week baseline period (June, 2017) and the 11-week evaluation period (July 24, 2017, to Oct 7, 2017). Workers' income was tied to their productivity. Compliance with study glasses was assessed at seven unannounced visits. Results were analysed on an intention-to-treat basis. This trial is registered with ClinicalTrials.gov, number NCT03228199. FINDINGS: Between July 3, 2017, and July 15, 2017, 1297 (48·1%) of 2699 permanent workers met the age criteria and consented for eye examinations. 751 (57·9%) fulfilled vision criteria and were randomly assigned to the intervention (n=376) or control (n=375) groups. Groups did not differ substantially in baseline characteristics. No participants owned glasses at baseline, 707 (94·1%) received the allocated intervention, and all were followed up and analysed. Between the baseline and evaluation periods, mean productivity in the intervention group increased from 25·0 kg per day to 34·8 kg per day (an increase of 9·84 kg per day), a significantly higher increase than in the control group (from 26·0 kg per day to 30·6 kg per day; an increase of 4·59 kg per day), corresponding to a between-group difference of 5·25 kg per day (95% CI 4·50-5·99; 21·7% relative productivity increase; effect size 1·01 [95% CI 0·86-1·16]; p<0·0001). Intervention-group compliance with study glasses reached 84·5% by closeout. Regression model predictors of greater productivity increase included intervention group membership (5·25 kg per day [95% CI 4·60-5·91], p<0·0001) and, among intervention participants, older age (p=0·039) and better compliance with the intervention (p<0·0001). INTERPRETATION: A substantial productivity increase was achieved in this rural cohort by providing glasses to correct presbyopia, with little cost and high intervention uptake. FUNDING: Clearly.

Ten years of NGDO action against river blindness.

For a decade, a dozen non-governmental development organizations (NGDOs) have organized themselves into a Geneva-based coordination group with the goal of global control of onchocerciasis through mass distribution of ivermectin (Mectizan(R)). Members of this group have worked with Ministries of Health and other partners to empower communities affected by the disease to take responsibility for their own treatment. The NGDO Group has played a key role in the governance of international onchocerciasis control effort, particularly as a partner within the African Programme for Onchocerciasis Control. Ten years on, it is now time to take stock of activities, review the lessons learned and confront future challenges.