The diluted atropine for inhibition of myopia progression in Korean children

Real-world outcomes of low-dose atropine therapy on myopia progression in an Australian cohort during the COVID-19 pandemic

BACKGROUND

To report the outcomes of low-dose atropine (0.01% and 0.05%) for preventing myopia progression in a real-world Australian cohort during the COVID-19 pandemic.

METHODS

Records of children presenting with myopia, from January 2016 to 2022, were retrospectively reviewed at a comprehensive ophthalmic practice. Children who discontinued treatment, ages >18, and cases with hereditary conditions were excluded. The rate of progression of myopia after treatment with atropine was compared with historical data to evaluate the effectiveness of the regime.

RESULTS

One hundred and one children (mean baseline spherical equivalent [SphE] [-3.70 +/- 2.09 D] and axial length [AL] [24.59 +/- 1.00 mm]) were analysed. The mean age of the children was 10.4 +/- 2.89 years and 61% were females. The average follow-up time was 17.9 +/- 12.5 months. The mean rate of progression of AL and SphE on 0.01% atropine eyedrops was 0.219 +/- 0.35 mm and - 0.250 +/- 0.86 D/year, respectively. 68.1% of the children treated with 0.01% atropine were mild progressors (<0.5 D change/year). Non-responders when commenced on a higher dose of atropine (0.05%) experienced a 93% (p = 0.012) and 30% reduction in SphE and AL growth rate, respectively. Family history, higher myopia or younger age at baseline and shorter duration of treatment were associated with steeper progression (p < 0.01). Both doses were well tolerated.

CONCLUSIONS

Low-dose atropine was shown to be beneficial in a real-world clinical setting, despite interruptions to follow-ups secondary to COVID-19 pandemic. A 0.05% dose of atropine may be effective in cases where 0.01% was ineffective.

Effect of 0.02% and 0.01% atropine on ocular biometrics: A two-year clinical trial

BACKGROUND

Several studies have shown that various concentrations of low-concentration atropine can reduce myopia progression and control axial elongation safely and efficiently in children. The aim of this study was to evaluate the effects of 0.02% and 0.01% atropine on ocular biometrics.

METHODS

Cohort study. 138 and 142 children were randomized to use either 0.02% or 0.01% atropine eye drops, respectively. They wore single-vision (SV) spectacles, with one drop of atropine applied to both eyes nightly. Controls (N = 120) wore only SV spectacles. Ocular and corneal astigmatism were calculated using Thibos vector analysis and split into J0 and J45.

RESULTS

The changes in cycloplegic spherical equivalent refraction (SER) and axial length (AL) were -0.81 ± 0.52D, -0.94 ± 0.59D, and -1.33 ± 0.72D; and 0.62 ± 0.29 mm, 0.72 ± 0.31 mm, and 0.89 ± 0.35 mm in the 0.02% and 0.01% atropine and control groups, respectively (all P < 0.05). Both anterior chamber depth (ACD) and ocular astigmatism (including J0) increased, and lens power decreased in the three groups (all P < 0.05). However, there were no differences in the changes in ACD, ocular astigmatism, and lens power among the three groups (all P > 0.05). Intraocular pressure (IOP), corneal curvature, ocular astigmatism J45, and corneal astigmatism (including J0 and J45) remained stable over time in the three groups (all P > 0.05). The contributions to SER progression from the changes in AL, lens and corneal power of the three groups were similar (P > 0.05). The contribution of AL change alone to the change in SER was 56.3%, 63.4% and 78.2% in the above corresponding three groups.

CONCLUSIONS

After 2 years, 0.02% and 0.01% atropine had no clinical effects on corneal and lens power, ocular and corneal astigmatism, ACD or IOP compared to the control group. 0.02% and 0.01% atropine helped to control myopia progression mainly by reducing AL elongation.

Classification-Based Approaches to Myopia Control in a Taiwanese Cohort

Purpose

Myopia is a disorder of growing prevalence in school-aged children worldwide, especially in Asia. Although low-dose atropine is recognized as an effective treatment to slow myopia progression, different studies have reported varying efficacies of treatment, and the optimal concentration of low-dose atropine remains an open question.

Methods

A two-stage approach was conducted in this study. First, an observational study was conducted to plot the axial length growth curve for Taiwanese children. Second, an interventional 2-year study was performed in which different concentrations of low-dose atropine were applied based upon the risk-level status from the first stage.

Results

A total of 4,091 subjects, consisting of 2,105 boys (51.5%) and 1,986 girls (48.5%), were enrolled in the first stage to plot the axial growth curve for Taiwanese children aged between 3 and 16 years. The percentage of children with myopia increased from 2.3% in 4-year-olds to 88.0% in 16-year-olds. At the second stage, a total of 886 subjects [307 (34.65%) at low risk, 358 (40.41%) at moderate risk and 221 (24.94%) at high risk] were enrolled to receive low-dose atropine based upon the risk level (0.02, 0.03, and 0.05%, respectively). With this approach, the mean annual myopia progression was −0.33, −0.57, and −0.82 D in the low-risk, moderate-risk and high-risk groups, respectively. Applying annual myopic progression < -1.0 D as a criterion for responder, the responder rates were 95.77, 83.52, and 70.59% in the low-risk, moderate-risk, and high-risk groups, respectively.

Conclusions

We proposed a classification-based approach involving different concentrations of low-dose atropine based upon an individual's risk-level status. With this approach, myopic progression can be effectively controlled in patients without exposure to atropine side effects due to exposure to a higher dose than actually needed.

Characteristics of responders to atropine 0.01% as treatment in Asian myopic children

Recently, low-concentration atropine (0.01%) has gained increased attention in controlling myopia progression with satisfying effects and minimal side effects. However, studies concerning responders to 0.01% atropine are limited. This retrospective observational cohort study aimed to determine the responder characteristics of 0.01% atropine in Asian children. One hundred forty children (aged between 3 and 15 years) receiving 0.01% atropine were analyzed for the factors influencing annual spherical equivalent changes (SE). The mean age was 9.13 (2.6) years, the mean baseline SE was - 1.56 (1.52) diopters (D), and the mean annual SE change was - 0.52 (0.49) D. A 58.63% responder rate (146/249) of myopic control was achieved with 0.01% atropine in our entire cohort under the criteria of less than 0.5 D of myopic progression annually. The subjects were stratified into 4 subgroups based on a cut-off point of baseline SE of - 1.5 D and baseline age of 9 years. The responder rate differed significantly with the highest being the youngest with the lowest myopia subgroups. Our results demonstrated that children with myopia better than - 1.5 D and younger than 9 years had the highest potential to achieve successful myopic control under 0.01% atropine therapy.

Varying Dose of Atropine in Slowing Myopia Progression in Children Over Different Follow-Up Periods by Meta-Analysis

Purpose: To evaluate the efficacy and safety of atropine for slowing myopia progression and to investigate whether the treatment effect remains constant with continuing treatment.

Method: Studies were retrieved from MEDLINE, EMBASE, and the Cochrane Library from their inception to May 2021, and the language was limited to English. Randomized controlled trials (RCTs) and cohort studies involving atropine in at least one intervention and placebo/non-atropine treatment in another as the control were included and subgroup analysis based on low dose (0.01%), moderate dose (0.01%–<0.5%), and high dose (0.5–1.0%) were conducted. The Cochrane Collaboration and Newcastle-Ottawa Scale were used to evaluate the quality of RCTs and cohort studies, respectively.

Results: Twelve RCTs and fifteen cohort studies involving 5,069 children aged 5 to 15 years were included. The weighted mean differences in myopia progression between the atropine and control groups were 0.73 diopters (D), 0.67 D, and 0.35 D per year for high-dose, moderate-dose, and low-dose atropine, respectively (χ² = 13.76; P = 0.001, I² = 85.5%). After removing studies that provided extreme findings, atropine demonstrated a significant dose-dependent effect on both refractive change and axial elongation, with higher dosages of atropine resulting in less myopia progression (r = 0.85; P = 0.004) and less axial elongation (r = −0.94; P = 0.005). Low-dose atropine showed less myopia progression (−0.23 D; P = 0.005) and less axial elongation (0.09 mm, P < 0.001) in the second year than in the first year, whereas in high-dose atropine more axial elongation (−0.15 mm, P = 0.003) was observed. The higher dose of atropine was associated with a higher incidence of adverse effects, such as photophobia with an odds ratio (OR) of 163.57, compared with an OR of 6.04 for low-dose atropine and 8.63 for moderate-dose atropine (P = 0.03).

Conclusion: Both the efficacy and adverse effects of atropine are dose-dependent in slowing myopia progression in children. The efficacy of high-dose atropine was reduced after the first year of treatment, whereas low-dose atropine had better efficacy in a longer follow-up period.

Safety and efficacy of 0.02% and 0.01% atropine on controlling myopia progression: a 2-year clinical trial

Four hundred myopic children randomly received atropine 0.02% (n = 138) or 0.01% (n = 142) in both eyes once-nightly or only wore single-vision spectacles (control group) (n = 120) for 2 years. Spherical equivalent refractive error (SER), axial length (AL), pupil diameter (PD), and amplitude of accommodation (AMP) were measured every 4 months. After 2 years, the SER changes were - 0.80 (0.52) D, - 0.93 (0.59) D and - 1.33 (0.72) D and the AL changes were 0.62 (0.29) mm, 0.72 (0.31) mm and 0.88 (0.35) mm in the 0.02% and 0.01% atropine groups and control group, respectively. There were significant differences between changes in SER and AL in the three groups (all P < 0.001). The changes in SER and AL in the 2nd year were similar to the changes in the 1st year in the three groups (all P > 0.05). From baseline to 2 years, the overall decrease in AMP and increase in PD were not significantly different in the two atropine groups, whereas the AMP and PD in the control group remained stable (all P > 0.05). 0.02% atropine had a better effect on myopia control than 0.01% atropine, and its effects on PD and AMP were similar to 0.01% atropine. 0.02% or 0.01% atropine controlled myopia progression and AL elongation synchronously and had similar effects on myopia control each year.

Influence of coronavirus disease 2019 on myopic progression in children treated with low-concentration atropine

Purpose

The outbreak of coronavirus disease 2019 (COVID-19) has caused many children to stay indoors. Increased near work and insufficient outdoor activities are considered important risk factors for myopic progression. This study aimed to compare the changes in myopic progression before and after COVID-19 in children treated with low-concentration atropine.

Methods

The records of 103 eyes of 103 children who were treated with low-concentration atropine eye drops were retrospectively reviewed. We classified children according to the concentration of atropine eye drops and children’s age. The beginning of the pre-COVID-19 period was set from January 2019 to May 2019, and the endpoint was set in March 2020. The beginning of the post-COVID-19 period was set in March 2020, and the endpoint was set from January 2021 to March 2021. We evaluated the questionnaires administered to children’s parents.

Results

A significant myopic progression was observed in the post-COVID-19 period compared to the pre-COVID-19 period in the 0.05% and 0.025% atropine groups (P < 0.001 and P = 0.020, respectively). For children aged 5 to 7 and 8 to 10 years, the axial elongations were significantly faster in the post-COVID-19 period than in the pre-COVID-19 period (P = 0.022 and P = 0.005, respectively). However, the rates of axial elongation and myopic progression were not significantly different between pre- and post-COVID-19 in children aged 11 to 15 years (P = 0.065 and P = 0.792, respectively). The average time spent using computers and smartphones and reading time were significantly increased, and the times of physical and outdoor activity were significantly decreased in the post-COVID-19 period compared to the pre-COVID-19 period.

Conclusions

The rates of myopic progression have increased substantially after the spread of COVID-19 with an increase in the home confinement of children. Therefore, it is necessary to control the environmental risk factors for myopia, even in children undergoing treatment for the inhibition of myopic progression.

Risk factors for rapid axial length elongation with low concentration atropine for myopia control

Three hundred and twenty-eight myopic children, randomized to use either 0.01% (N = 166) or 0.02% (N = 162) atropine were enrolled in this study. Gender, age, body mass index(BMI), parental myopia status, atropine concentration used, pupil diameter, amplitude of accommodation, spherical equivalent refractive error (SER), anterior chamber depth (ACD) and axial length (AL) were collected at baseline and 1 year after using atropine. Rapid AL elongation was defined as > 0.36 mm growth per year. Univariate analyses showed that children with rapid AL elongation tend to be younger, have a smaller BMI, use of 0.01% atropine, narrow ACD, lower SER, shorter AL, smaller change in pupil diameter between 1 year and baseline (all P < 0.05). Multivariate logistic regression analyses confirmed that rapid AL elongation was associated with children that were younger at baseline (P < 0.0001), use of 0.01% atropine (P = 0.04), a shorter baseline AL (P = 0.03) and a smaller change in pupil diameter between 1 year and baseline (P = 0.04). Younger children with shorter AL at baseline, less change in their pupil diameter with atropine treatment and using the lower of the two atropine concentrations may undergo rapid AL elongation over a 12 months myopia control treatment period.

The Effect of Long-Term Low-Dose Atropine on Refractive Progression in Myopic Australian School Children

Myopia will affect half the global population by 2050 and is a leading cause of vision impairment. High-dose atropine slows myopia progression but with undesirable side-effects. Low-dose atropine is an alternative. We report the effects of 0.01% or 0.005% atropine eye drops on myopia progression in 13 Australian children aged between 2 and 18 years and observed for 2 years without and up to 5 years (mean 2.8 years) with treatment. Prior to treatment, myopia progression was either ‘slow’ (more positive than −0.5 D/year; mean −0.19 D/year) or ‘fast’ (more negative than −0.5 D/year; mean −1.01 D/year). Atropine reduced myopic progression rates (slow: −0.07 D/year, fast: −0.25 D/year, combined: before: −0.74, during: −0.18 D/year, p = 0.03). Rebound occurred in 3/4 eyes that ceased atropine. Atropine halved axial growth in the ‘Slow’ group relative to an age-matched model of untreated myopes (0.098 vs. 0.196 mm/year, p < 0.001) but was double that in emmetropes (0.051 mm/year, p < 0.01). Atropine did not slow axial growth in ‘fast’ progressors compared to the age-matched untreated myope model (0.265 vs. 0.245 mm/year, p = 0.754, Power = 0.8). Adverse effects (69% of patients) included dilated pupils (6/13) more common in children with blue eyes (5/7, p = 0.04). Low-dose atropine could not remove initial myopia offsets suggesting treatment should commence in at-risk children as young as possible.

The Effects of 0.01% Atropine on Adult Myopes' Contrast Sensitivity

Purpose

Atropine at a low concentration is considered a safe and effective treatment to mitigate myopia progression. However, the potential unwanted side effects of administering atropine at a low dose on visual functions other than best corrected visual acuity has not been investigated. In this study, we investigate the short-term (12,16, and 20 h) and long-term (1, 2, and 4 weeks) effects of 0.01% atropine (i.e., 0.1 mg/ml) on contrast sensitivity (CS) in patients with myopia.

Methods

Thirty adults (23.33 ± 2.93 years old) with myopia between -1.00 and -6.00 diopters (D), astigmatism of -1.50 D or less, and anisometropia of 1.00 D or less, participated in this prospective, masked, placebo-controlled, randomized study. The participants were randomly assigned to receive 0.01% atropine or polyvinyl alcohol eye drops once nightly to both eyes for four weeks. CS was measured binocularly at baseline and 12, 16, 20 h, 1, 2, and 4 weeks after the first use of the eye drops.

Results

There was no statistically significant differences of CS found between atropine and placebo-controlled groups in both short-term and long-term. There was no statistically significant interaction effect found between the time and group.

Conclusion

We demonstrated no significant deleterious effect of 0.01% atropine on adult myopes’ CS.

Efficacy and safety of atropine to control myopia progression: a systematic review and meta-analysis

Background

The effect and safety of atropine on delaying the progression of myopia has been extensively studied, but its optimal dose is still unclear. Therefore, the purpose of this meta-analysis is to systematically evaluate the safety and effectiveness of atropine in controlling the progression of myopia, and to explore the relationship between the dose of atropine and the effectiveness of controlling the progression of myopia.

Methods

This work was done through the data searched from PubMed, MEDLINE, EMBASE, and the Cochrane Central Register of Controlled Trials. The Cochrane Handbook was also used to evaluate the quality of the included studies. In addition, a meta-analysis was performed using Revman5.3 software.

Results

A total of 10 randomized controlled trials (RCTs) were included. Myopia progression was mitigated greater in the atropine treatment group than that in the control group, with MD = − 0.80, 95% CI (− 0.94, − 0.66) during the whole observation period. There was a statistical difference among 0.05, 0.5, and 1.0% atropine (P = 0.004). In addition, less axial elongation was shown, with MD = − 0.26, 95% CI (− 0.33, − 0.18) during the whole observation period.

Conclusion

The effectiveness of atropine in controlling the progression of myopia was dose related. A 0.05% atropine was likely to be the optimal dose.

Myopia Outcome Study of Atropine in Children (MOSAIC): an investigator-led, double-masked, placebo-controlled, randomised clinical trial protocol

Background: The Myopia Outcome Study of Atropine in Children (MOSAIC) aims to explore the efficacy, safety, acceptability and mechanisms of action of 0.01% unpreserved atropine for myopia control in a European population. Methods: MOSAIC is an investigator-led, double-masked, placebo-controlled, randomised clinical trial (RCT) investigating the efficacy, safety and mechanisms of action of 0.01% atropine for managing progression of myopia. During Phase 1 of the trial, 250 children aged 6-16 years with progressive myopia instil eye drops once nightly in both eyes from randomisation to month 24. From month 24 to 36  participants are re-randomised in Phase 2 of the trial, into continued 0.01% atropine, and washout, at 1:1 ratio for those participants initially randomised to the intervention arm (n=167), during which any potential rebound effects on cessation of treatment will be monitored. All participants initially assigned to the placebo (n=83) crossover to the intervention arm of the study for Phase 2, and from month 24 to 36, instil 0.01% atropine eye drops in both eyes once nightly. Further treatment and monitoring beyond 36 months is planned (Phase 3) and will be designed dependent on the outcomes of Phase 1. Results: The primary outcome measure is cycloplegic spherical equivalent refractive error progression at 24 months. Secondary outcome measures include axial length change as well as the rebound, safety and acceptability profile of 0.01% atropine. Additional analyses will include the mechanisms of action of 0.01% atropine for myopia control. Conclusions: The generalisability of results from previous clinical trials investigating atropine for myopia control is limited by the predominantly Asian ethnicity of previous study populations. MOSAIC is the first RCT to explore the efficacy, safety and mechanisms of action of unpreserved 0.01% atropine in a predominantly White population.

Myopia Outcome Study of Atropine in Children (MOSAIC): an investigator-led, double-masked, placebo-controlled, randomised clinical trial protocol

Background: The Myopia Outcome Study of Atropine in Children (MOSAIC) aims to explore the efficacy, safety, acceptability and mechanisms of action of 0.01% unpreserved atropine for myopia control in a European population.

Methods: MOSAIC is an investigator-led, double-masked, placebo-controlled, randomised clinical trial (RCT) investigating the efficacy, safety and mechanisms of action of 0.01% atropine for managing progression of myopia. During Phase 1 of the trial, 250 children aged 6-16 years with progressive myopia instil eye drops once nightly in both eyes from randomisation to month 24. No treatment is given during Phase 2 from month 24 to 36 (washout period) for those participants initially randomised to the intervention arm (n=167), during which any potential rebound effects on cessation of treatment will be monitored. All participants initially assigned to the placebo (n=83) crossover to the intervention arm of the study for Phase 2, and from month 24 to 36, instil 0.01% atropine eye drops in both eyes once nightly. Further treatment and monitoring beyond 36 months is planned (Phase 3) and will be designed dependent on the outcomes of Phase 1.

Results: The primary outcome measure is cycloplegic spherical equivalent refractive error progression at 24 months. Secondary outcome measures include axial length change as well as the rebound, safety and acceptability profile of 0.01% atropine. Additional analyses will include the mechanisms of action of 0.01% atropine for myopia control.

Conclusions: The generalisability of results from previous clinical trials investigating atropine for myopia control is limited by the predominantly Asian ethnicity of previous study populations. MOSAIC is the first RCT to explore the efficacy, safety and mechanisms of action of unpreserved 0.01% atropine in a predominantly White population.

Trial registration: ISRCTN: ISRCTN36732601 (04/10/2017), EudraCTdatabase 2016-003340-37 (03/07/2018).