Myopia Progression Study Research Articles

Can we really distinguish 'responders' from 'non-responders' to myopia control interventions?

It is common to hear talk of 'responders' and 'non-responders' with respect to myopia control interventions. We consider the reality of distinguishing these sub-groups using data from the first year of the Low-concentration Atropine for Myopia Progression (LAMP) study. The first year of the LAMP study was a robustly designed, placebo-controlled trial of three different low concentrations of atropine using a large sample size (N > 100 randomised to each group). The authors subsequently published mean axial elongation and myopia progression rates by age group. We used these data to calculate efficacy in terms of both absolute reduction in myopic progression and absolute reduction in axial elongation for each of the different atropine concentrations at each age group. We then compared these efficacy data to the overall progression for each of the two progression metrics. Plotting efficacy as a function of overall myopia progression and axial elongation for each of the different atropine concentrations demonstrates the invariant nature of efficacy, in terms of clinically meaningful reduction in progression, despite a substantial range of underlying overall progression. That is, faster progressors-the so-called non-responders-achieved similar reduction in axial elongation and myopia progression as the slower progressors-the so-called responders-within the various atropine treatment groups. The use of the terms, responders and non-responders, during myopia progression interventions is not supported by evidence. Those designated as such may simply be slower or faster progressors, who, on average achieve the same benefit from treatment.

Five-Year Clinical Trial of the Low-Concentration Atropine for Myopia Progression (LAMP) Study: Phase 4 Report

PurposeTo evaluate (1) the long-term efficacy of low-concentration atropine over 5 years, (2) the proportion of children requiring retreatment and associated factors (3) the efficacy of pro re nata (PRN) retreatment using 0.05% atropine from year 3 to 5. DesignA randomized, double-masked extended trial. MethodsChildren aged 4–12 years originally from the Low-Concentration Atropine for Myopia Progression study were followed up for 5 years. During the third year, children in each group originally on 0.05%, 0.025%, and 0.01% atropine were randomized to continued treatment and treatment cessation. During years 4 and 5, all continued treatment subgroups were switched to 0.05% atropine for continued treatment, while all treatment cessation subgroups followed a PRN retreatment protocol to resume 0.05% atropine for children with myopic progressions of 0.5D or more over one year. Generalized estimating equations were used to compare the changes in spherical equivalent (SE) progression and axial length (AL) elongation among groups. Outcomes Measures(1) Changes in SE and AL over 5 years in different groups over 5 years; (2) Proportion of children who needed retreatment; (3) Changes in SE and AL in continued treatment and PRN retreatment groups from years 3 to 5. Results269 (82.5%) of 326 children from the third year completed 5 years of follow-up. Over 5 years, the cumulative mean SE progressions were –1.34±1.40D, –1.97±1.03D, and –2.34±1.71D for the continued treatment groups with initial 0.05%, 0.025%, and 0.01% atropine respectively (P=0.02). Similar trends were observed in AL elongation (P=0.01). Among the PRN retreatment group, 87.9%(94/107) of children needed retreatment. The proportion of retreatment across all studied concentrations is similar (P=0.76). The SE progressions for continued treatment and PRN retreatment groups from years 3 to 5 were – 0.97D±0.82D, and –1.00±0.74D (P=0.55), and the AL elongations were 0.51±0.34mm, and 0.49±0.32mm (P=0.84), respectively. ConclusionsOver 5 years, the continued 0.05% atropine treatment demonstrated good efficacy for myopia control. The majority of children needed to restart treatment after atropine cessation at year 3. Restarted treatment with 0.05% atropine achieved similar efficacy as continued treatment. Children should be considered for retreatment if myopia progresses after treatment cessation.

Benefits and limitations of low dose atropine

Atropine is an anti‐muscarinic agent and can be used as a monotherapy or as a combination to slow the progression of myopia. It has been advocated as the first line of treatment in children with lower cost compared with other therapies, and it is a good option for children intolerant to contact lenses and when other treatment options are rejected by parents. The major limitations of topical atropine therapy include the adverse effects with higher concentrations (0.1% and higher), such as reduced amplitude of accommodation and photophobia, and the need for daily dosing. Efficacy of low‐dose atropine treatment has been confirmed by several meta‐analysis showing reduced SE progression and decreased axial elongation. The results from the Low‐Concentration Atropine for Myopia Progression (LAMP) study (3‐year RCT results) in Chinese children showed that 0.05% atropine conferred the best efficacy compared with 0.025% and 0.01%. However, it was postulated that the use of 0.05% topical atropine in Caucasian children may lead to more side effects compared to 0.01%, which can compromise parent's acceptance or children's compliance. The efficacy and safety of 8 atropine concentrations for myopia control in children was reported in a recent network meta‐analysis, in which the 0.05% was found the most beneficial for control of overall myopia progression. It is generally believed that the atropine dose should be adjusted based on the risk factors and progression.

The 18th International Myopia Conference 2022 in Rotterdam, The Netherlands.

The 18th International Myopia Conference 2022 in Rotterdam, The Netherlands.

Myopia control and prevention: From lifestyle to low-concentration atropine. The 2022 Josh Wallman Memorial Lecture.

The purpose of this study was to explore the findings from the Hong Kong Children Eye Study and the Low Concentration Atropine for Myopia Progression (LAMP-1) Study. The incidence of myopia among schoolchildren in Hong Kong more than doubled during the COVID-19 pandemic, with outdoor time decreased significantly and screen time increased. The change in lifestyle during the COVID-19 pandemic aggravated myopia development. Low-concentration atropine (0.05%, 0.025% and 0.01%) is effective in reducing myopia progression with a concentration-related response. This concentration-dependent response was maintained throughout a 3-year follow-up period, and all low concentrations were well tolerated. An age-dependent effect was observed in each treatment group with 0.05%, 0.025% and 0.01% atropine. Younger age was associated with a poor treatment response to low-concentration atropine. Additionally, low-concentration atropine induced choroidal thickening along a concentration-dependent response throughout the treatment period. During the third year, continued atropine treatment achieved a better effect across all concentrations compared with the washout regimen. Stopping treatment at an older age and receiving lower concentration were associated with a smaller rebound effect. However, differences in the rebound effect were clinically small across all the three concentrations studied.

Efficacy in Myopia Control: The Low-Concentration Atropine for Myopia Progression (LAMP) Study

The 3-year Low-Concentration Atropine for Myopia Progression (LAMP) Study has greatly enhanced knowledge of the use of low-concentration atropine for myopia control. 1 Yam JC Jiang Y Tang SM et al. Low-Concentration Atropine for Myopia Progression (LAMP) Study: A Randomized, Double-Blinded, Placebo-Controlled Trial of 0.05%, 0.025%, and 0.01% Atropine Eye Drops in Myopia Control. Ophthalmology. 2019; 126: 113-124 Abstract Full Text Full Text PDF PubMed Scopus (267) Google Scholar ,2 Yam JC Zhang XJ Zhang Y et al. Three-Year Clinical Trial of Low-Concentration Atropine for Myopia Progression (LAMP) Study: Continued Versus Washout: Phase 3 Report. Ophthalmology. 2022; 129: 308-321 Abstract Full Text Full Text PDF Scopus (27) Google Scholar In year 1, children were randomized to receive 0.05%, 0.025%, or 0.01% atropine, or placebo. 1 Yam JC Jiang Y Tang SM et al. Low-Concentration Atropine for Myopia Progression (LAMP) Study: A Randomized, Double-Blinded, Placebo-Controlled Trial of 0.05%, 0.025%, and 0.01% Atropine Eye Drops in Myopia Control. Ophthalmology. 2019; 126: 113-124 Abstract Full Text Full Text PDF PubMed Scopus (267) Google Scholar Compared to the placebo, axial elongation was slowed 0.21, 0.12, and 0.05 mm by 0.05%, 0.025%, and 0.01% atropine, respectively. Myopia progression showed a corresponding slowing of 0.54, 0.35, and 0.22 D.

Benefits and limitations of the low dose atropine use

AbstractAtropine is an anti‐muscarinic agent and can be used as a monotherapy or as a combination to slow the progression of myopia. It has been advocated as the first line of treatment in children with lower cost compared with other therapies, and it is a good option for children intolerant to contact lenses and when other treatment options are rejected by parents. The major limitations of topical atropine therapy include the adverse effects with higher concentrations (0.1% and higher), such as reduced amplitude of accommodation and photophobia, and the need for daily dosing. Efficacy of low‐dose atropine treatment has been confirmed by several meta‐analysis showing reduced SE progression and decreased axial elongation. The results from the Low‐Concentration Atropine for Myopia Progression (LAMP) study (3‐year RCT results) in Chinese children showed that 0.05% atropine conferred the best efficacy compared with 0.025% and 0.01%. However, it was postulated that the use of 0.05% topical atropine in Caucasian children may lead to more side effects compared to 0.01%, which can compromise parent's acceptance or children's compliance. The efficacy and safety of 8 atropine concentrations for myopia control in children was reported in a recent network meta‐analysis, in which the 0.05% was found the most beneficial for control of overall myopia progression. It is generally believed that the atropine dose should be adjusted based on the risk factors and progression.

Efficacy and Safety of Consecutive Use of 1% and 0.01% Atropine for Myopia Control in Chinese Children: The Atropine for Children and Adolescent Myopia Progression Study.

IntroductionThe purpose of this study was to investigate the efficacy and safety of consecutive use of 1% and 0.01% atropine compared with 0.01% atropine alone over 1 year.MethodsA total of 207 participants aged 6–12 years with myopia of − 0.50 to − 6.00 D in both eyes were enrolled in this randomized, controlled, non-masked trial and randomly assigned (1:1) to groups A and B. Group A received 1% atropine weekly and were tapered to 0.01% atropine daily at the 6-month visit, and group B received 0.01% atropine daily for 1 year.ResultsOf the 207 participants, 109 were female (52.7%) and the mean (± standard deviation) age was 8.92 ± 1.61 years. Ninety-one participants (87.5%) in group A and 80 participants (77.7%) in group B completed the 1-year treatment. Group A exhibited less refraction progression (− 0.53 ± 0.49 D vs. − 0.74 ± 0.52 D; P = 0.01) and axial elongation (0.26 ± 0.17 mm vs. 0.36 ± 0.21 mm; P < 0.001) over 1 year compared with group B. The changes in refraction (− 0.82 ± 0.45 D vs. − 0.46 ± 0.35 D; P < 0.001) and axial length (0.29 ± 0.12 mm vs. 0.17 ± 0.11 mm; P < 0.001) during the second 6 months in group A were greater than those in group B, with 72.5% of participants presenting refraction rebound. No serious adverse events were reported.ConclusionsThe 1-year results preliminarily suggest that consecutive use of 1% and 0.01% atropine confers an overall better effect in slowing myopia progression than 0.01% atropine alone, despite myopia rebound after the concentration switch. Both regimens were well tolerated. The long-term efficacy and rebound after the concentration switch and regimen optimization warrant future studies to determine.Trial Registration NumberClinical Trials.gov PRS (Registration No. NCT03949101).Supplementary InformationThe online version contains supplementary material available at 10.1007/s40123-022-00572-1.

Smartphone-Acquired Anterior Segment Images for Deep Learning Prediction of Anterior Chamber Depth: A Proof-of-Concept Study

PurposeTo develop a deep learning (DL) algorithm for predicting anterior chamber depth (ACD) from smartphone-acquired anterior segment photographs.MethodsFor algorithm development, we included 4,157 eyes from 2,084 Chinese primary school students (aged 11–15 years) from Mojiang Myopia Progression Study (MMPS). All participants had with ACD measurement measured with Lenstar (LS 900) and anterior segment photographs acquired from a smartphone (iPhone Xs), which was mounted on slit lamp and under diffuses lighting. The anterior segment photographs were randomly selected by person into training (80%, no. of eyes = 3,326) and testing (20%, no. of eyes = 831) dataset. We excluded participants with intraocular surgery history or pronounced corneal haze. A convolutional neural network was developed to predict ACD based on these anterior segment photographs. To determine the accuracy of our algorithm, we measured the mean absolute error (MAE) and coefficient of determination (R2) were evaluated. Bland Altman plot was used to illustrate the agreement between DL-predicted and measured ACD values.ResultsIn the test set of 831 eyes, the mean measured ACD was 3.06 ± 0.25 mm, and the mean DL-predicted ACD was 3.10 ± 0.20 mm. The MAE was 0.16 ± 0.13 mm, and R2 was 0.40 between the predicted and measured ACD. The overall mean difference was −0.04 ± 0.20 mm, with 95% limits of agreement ranging between −0.43 and 0.34 mm. The generated saliency maps showed that the algorithm mainly utilized central corneal region (i.e., the site where ACD is clinically measured typically) in making its prediction, providing further plausibility to the algorithm's prediction.ConclusionsWe developed a DL algorithm to estimate ACD based on smartphone-acquired anterior segment photographs. Upon further validation, our algorithm may be further refined for use as a ACD screening tool in rural localities where means of assessing ocular biometry is not readily available. This is particularly important in China where the risk of primary angle closure disease is high and often undetected.

The Association of Choroidal Thickening by Atropine With Treatment Effects for Myopia: Two-Year Clinical Trial of the Low-concentration Atropine for Myopia Progression (LAMP) Study

To evaluate longitudinal changes in subfoveal choroidal thickness (SFChT) among children receiving atropine 0.05%, 0.025%, or 0.01% over 2 years and their associations with treatment outcomes in myopia control. Double-blinded randomized controlled trial. SFChT was measured at 4-month intervals using spectral domain optical coherence tomography. Cycloplegic spherical equivalent (SE), axial length (AL), best-corrected visual acuity, parental SE, outdoor time, near work diopter hours, and treatment compliance were also measured. 314 children were included with qualified choroidal data. The 2-year changes in SFChT from baseline were 21.15 ± 32.99 µm, 3.34 ± 25.30 µm, and -0.30 ± 27.15 µm for the atropine 0.05%, 0.025%, and 0.01% groups, respectively (P < .001). A concentration-dependent response was observed, with thicker choroids at higher atropine concentrations (β=0.89, P < .001). Mean SFChT thickness significantly increased at 4 months in the atropine 0.025% (P = .001) and 0.05% groups (P < .001) and then remained stable until the end of the second year (P > .05 for all groups). Over 2 years, an increase in SFChT was associated with slower SE progression (β=0.074, P < .001) and reduced AL elongation (β=-0.045, P < .001). In the mediation analysis, 18.45% of the effect on SE progression from atropine 0.05% was mediated via its choroidal thickening. Low concentration atropine induced a choroidal thickening effect along a concentration-dependent response throughout the treatment period. The choroidal thickening was associated with a slower SE progression and AL elongation among all the treatment groups. Choroidal response can be used for assessment of long-term treatment outcomes and as a guide for concentration titrations of atropine.

Three-Year Clinical Trial of Low-Concentration Atropine for Myopia Progression (LAMP) Study: Continued Versus Washout: Phase 3 Report

(1) To compare the efficacy of continued and stopping treatment for 0.05%, 0.025%, and 0.01% atropine during the third year. (2) To evaluate the efficacy of continued treatment over 3 years. (3) To investigate the rebound phenomenon and its determinants after cessation of treatment. A randomized, double-masked extended trial. A total of 350 of 438 children aged 4 to 12 years originally recruited into the Low-Concentration Atropine for Myopia Progression (LAMP) study. At the beginning of the third year, children in each group were randomized at a 1:1 ratio to continued treatment and washout subgroups. Cycloplegic spherical equivalent (SE) refraction and axial length (AL) were measured at 4-month intervals. Changes in SE and AL between groups. A total of 326 children completed 3 years of follow-up. During the third year, SE progression and AL elongation were faster in the washout subgroups than in the continued treatment groups across all concentrations: -0.68 ± 0.49 diopters (D) versus -0.28 ± 0.42 D (P < 0.001) and 0.33 ± 0.17 mm versus 0.17 ± 0.14 mm (P< 0.001) for the 0.05%; -0.57 ± 0.38 D versus -0.35 ± 0.37 D (P= 0.004) and 0.29 ± 0.14 mm versus 0.20 ± 0.15 mm (P= 0.001) for the 0.025%; -0.56 ± 0.40 D versus -0.38 ± 0.49 D (P= 0.04) and 0.29 ± 0.15 mm versus 0.24 ± 0.18 mm (P= 0.13) for the 0.01%. Over the 3-year period, SE progressions were -0.73 ± 1.04 D, -1.31 ± 0.92 D, and -1.60 ± 1.32 D (P= 0.001) for the 0.05%, 0.025%, and 0.01% groups in the continued treatment subgroups, respectively, and-1.15 ± 1.13 D, -1.47 ± 0.77 D, and -1.81 ± 1.10 D (P= 0.03), respectively, in the washout subgroup. The respective AL elongations were 0.50 ± 0.40 mm, 0.74 ± 0.41 mm, and 0.89 ± 0.53 mm (P < 0.001) for the continued treatment subgroups and 0.70 ± 0.47 mm, 0.82 ± 0.37 mm, and 0.98 ± 0.48 mm (P= 0.04) for the washout subgroup. The rebound SE progressions during washout were concentration dependent, but their differences were clinically small (P= 0.15). Older age and lower concentration were associated with smaller rebound effects in both SE progression (P < 0.001) and AL elongation (P < 0.001). During the third year, continued atropine treatment achieved a better effect across all concentrations compared with the washout regimen. 0.05% atropine remained the optimal concentration over 3 years in Chinese children. The differences in rebound effects were clinically small across all 3 studied atropine concentrations. Stopping treatment at an older age and lower concentration are associated with a smaller rebound.

Side effects of topical atropine 0.05% compared to 0.01% for myopia control in German school children: a pilot study

PurposeBased on findings of the Asian low-concentration atropine for myopia progression study, a concentration of 0.05% has been proposed as a good compromise between safety and efficacy for myopia control. However, no data on side effects have been published so far in Caucasian children receiving this dose.MethodsPrior to commencement of bilateral atropine treatment with 0.05% atropine, 19 myopic children aged 5 to 15 years were treated in only one eye at bedtime leaving the other eye as a control. Pupil size, accommodation amplitude and near visual acuity were measured at 10:00 a.m. the next day and compared to the untreated contralateral control eye. The results were then compared to a cohort of 18 children whose treatment with 0.01% atropine commenced in a similar fashion.ResultsTwelve children (63%) reported visual impairment or reading difficulties. Anisocoria was 2.9 ± 1.1 mm. In comparison, 0.01% atropine led to a significantly less anisocoria of 0.8 ± 0.7 mm (p < 0.0001). Accommodation was decreased by − 4.2 ± 3.8 D in 0.05% atropine treated eyes, whereas 0.01% atropine induced hypoaccommodation of − 0.05 ± 2.5 D (p < 0.01). Near visual acuity was not significantly reduced in eyes treated with 0.05% atropine compared to 0.01% atropine (p = 0.26).ConclusionCompared to 0.01%, our data indicate stronger more relevant side effects of 0.05% topical atropine in young Caucasian children with progressive myopia as recently reported in Asian children, potentially compromising acceptance and compliance.

Age Effect on Treatment Responses to 0.05%, 0.025%, and 0.01% Atropine: Low-Concentration Atropine for Myopia Progression Study

To investigate the effect of age at treatment and other factors on treatment response to atropine in the Low-Concentration Atropine for Myopia Progression (LAMP) Study. Secondary analysis from a randomized trial. Three hundred fifty children aged 4 to 12 years who originally were assigned to receive 0.05%, 0.025%, or 0.01% atropine or placebo once daily, and who completed 2 years of the LAMP Study, were included. In the second year, the placebo group was switched to the 0.05% atropine group. Potential predictive factors for change in spherical equivalent (SE) and axial length (AL) over 2 years were evaluated by generalized estimating equations in each treatment group. Evaluated factors included age at treatment, gender, baseline refraction, parental myopia, time outdoors, diopter hours of near work, and treatment compliance. Estimated mean values and 95% confidence intervals (CIs) of change in SE and AL over 2 years also were generated. Factors associated with SE change and AL change over 2 years were the primary outcome measures. Associated factors during the first year were secondary outcome measures. In 0.05%, 0.025%, and 0.01% atropine groups, younger age was the only factor associated with SE progression (coefficient of 0.14, 0.15, and 0.20, respectively) and AL elongation (coefficient of -0.10, -0.11, and -0.12, respectively) over 2 years; the younger the age, the poorer the response. At each year of age from 4 to 12 years across the treatment groups, higher-concentration atropine showed a better treatment response, followinga concentration-dependent effect (Ptrend <0.05 for each age group). In addition, the mean SE progression in 6-year-old children receiving 0.05% atropine (-0.90 diopter [D]; 95% CI, -0.99 to -0.82) was similar to that of 8-year-old children receiving 0.025% atropine (-0.89 D; 95% CI, -0.94 to -0.83) and 10-year-old children receiving 0.01% atropine (-0.92 D; 95% CI, -0.99 to -0.85). All concentrations were well tolerated in all age groups. Younger age is associated with poor treatment response to low-concentration atropine at 0.05%, 0.025%, and 0.01%. Among concentrations studied, younger children required the highest 0.05% concentration to achieve similar reduction in myopic progression as older children receiving lower concentrations.

Prevalence of Refractive Errors in the Total Population and the Analysis of Myopic Progression in Adults Aged 20 to 39 in the Urban Area of Tirana, Albania

This study is a retrospective analysis of data stored digitally for 13 years in a Vision Center located in the urban area of Tirana, Albania. In a population of 19,686 people (39.5% M and 60.5% F) who met the criteria, there was a prevalence of astigmatism 42% (12% only astigmatism, 30% associated with hyperopia or myopia), myopia 25%, hyperopia 22% and 24% presbyopic prescriptions for the medium and near distance. The myopia progression study (mean spherical equivalent) indicates that 20% of people had no change, 42% had an increase in myopic correction from 0.25D to 0.50D, 17% from 0.75D to 1.00D, 11% from 1.25D to 1.50D, 5% from 1.75D to 2.00D and 5% of the population had myopic progression greater than 2.00D.

The Effect of Eye Exercises of Acupoints on Myopia Progression: A 3-Year Cohort Report from the Beijing Myopia Progression Study.

PurposeTo investigate the impact of eye exercises of acupoints on myopic progression among Chinese urban students.MethodsThe Beijing Myopia Progression Study (BMPS) was a three-year cohort study, with 386 students (aged 6–17 years) enrolled at baseline. These students were invited to be reexamined in the years 2011, 2012, and 2013. The student’s cycloplegic refraction at each visit and the parental non-cycloplegic refraction at baseline were performed. Students were also required to complete the eye exercise of acupoints questionnaire and the convergence insufficiency symptom survey (CISS).ResultsAt the final follow-up, 226 students (57.2%) with complete refraction and eye exercises questionnaire data were enrolled in the present study. In the multivariate analysis, only students who performed the eye exercises twice or more per day had less myopic refractive change (β=0.32, p=0.04), as compared to those who performed the eye exercises less than twice per day. No significant association was found between the CISS score and the refractive change for items in the eye exercises questionnaire.ConclusionIn this study cohort, the Chinese eye exercises of acupoints had a modest effect on reducing myopic progression among Chinese urban students aged 6 to 17 years. The precise mechanism remains unclear, especially in the absence of a control group.

The association between nearwork-induced transient myopia and progression of refractive error: A 3-year cohort report from Beijing Myopia Progression Study

PurposeTo investigate the natural change of nearwork-induced transient myopia (NITM), and its association with the progression of refractive error. MethodsStudents of the Beijing Myopia Progression Study were examined at baseline and follow-up examinations, which included cycloplegic autorefraction. Initial NITM and its decay were assessed objectively immediately after binocularly-viewing and performing a sustained 5-minute near task (20 cm). ResultsThere were 223 students with both NITM and cycloplegic refractive data enrolled. There were 142 myopic (63.7%), 32 emmetropic (14.4%), and 49 hyperopic (22.0%) students according to their baseline cycloplegic refraction. The annual refractive change was −0.45 (−0.73, −0.21) D. From the baseline to the one-year and two-year follow-up periods, the initial NITM (median) increased significantly in the myopic students (0.16, 0.21, and 0.20D, p = 0.01, respectively). The overall proportion of NITM decay types shifted significantly from none being induced at baseline (non-induced: 17.0%, complete decay 57.4%, incomplete decay 25.6%) to incomplete decay at the 2-year follow-up (non-induced: 6.7%, complete decay 65.0%, incomplete decay 28.3%, p = 0.01). For the hyperopic students, after adjusting for risk factors, for every 1 diopter increase in the initial NITM at baseline, there was approximately a −1.48 diopter more relative myopic refractive progression (p = 0.01). No significant association was found between refractive change and the NITM parameters for either the myopic or emmetropic students after adjusting for the same confounders. However, this relation was significant in the hyperopes (p = 0.01). ConclusionNITM was only found to be significantly associated with the progression of a myopic refractive shift among the hyperopes.

Differential Effects on Ocular Biometrics by 0.05%, 0.025%, and 0.01% Atropine: Low-Concentration Atropine for Myopia Progression Study

To evaluate changes in ocular biometrics in groups receiving 0.05%, 0.025%, and 0.01% atropine compared with placebo over 1 year based on the Low-Concentration Atropine for Myopia Progression (LAMP) study. Double-blinded, randomized, placebo-controlled trial. Three hundred eighty-three children aged 4 to 12 years who were assigned randomly to receive 0.05%, 0.025%, 0.01% atropine, or placebo once daily in both eyes and completed the first year of the LAMP study. Cycloplegic spherical equivalent (SE), axial length (AL), corneal curvature (K), and anterior chamber depth (ACD) were measured by IOLMaster. Corneal astigmatism and lens power were calculated. The ocular biometric parameter changes were compared among groups. Contributions to SE progression from ocular parameters were determined and compared among groups. Changes in ocular biometrics and their associations with the changes in SE. Over 1 year, changes in AL were 0.20 ± 0.25 mm, 0.29 ± 0.20 mm, 0.36 ± 0.29 mm, and 0.41 ± 0.22 mm in the 0.05% atropine, 0.025% atropine, 0.01% atropine, and placebo groups, respectively (P < 0.001), with a concentration-dependent response. Corneal power remained stable, and its changes were similar across all atropine concentrations: -0.02 ± 0.14 diopter (D), -0.01 ± 0.14 D, -0.01 ± 0.12 D, and 0.01 ± 0.14 D in the 0.05% atropine, 0.025% atropine, 0.01% atropine, and placebo groups, respectively (P= 0.10). Lens power decreased over time in each concentration, but its changes also were similar across all concentrations: -0.31 ± 0.43 D, -0.38 ± 0.47 D, -0.40 ± 0.43 D, and -0.41 ± 0.43 D in the 0.05% atropine, 0.025% atropine, 0.01% atropine, and placebo groups, respectively (P= 0.24). Changes in ACD remained similar across all concentrations (P= 0.41). The contributions to SE progression from the ocular biometric changes after adjusting for age and gender in each concentration were similar across all groups (P > 0.05). Low-concentrations of atropine (0.05%, 0.025%, and 0.01%) have no clinical effect on corneal or lens power. Antimyopic effects of low-concentration atropine act mainly on reducing AL elongation, and therefore could reduce the risk of subsequent myopia complications.

Two-Year Clinical Trial of the Low-Concentration Atropine for Myopia Progression (LAMP) Study: Phase 2 Report

To evaluate the efficacy and safety of 0.05%, 0.025%, and 0.01% atropine eye drops over 2 years to determine which is the optimal concentration for longer-term myopia control. Randomized, double-masked trial extended from the Low-Concentration Atropine for Myopia Progression (LAMP) Study. Three hundred eighty-three of 438 children (87%) aged 4 to 12 years with myopia of at least -1.0 diopter (D) originally randomized to receive atropine 0.05%, 0.025%, 0.01%, or placebo once daily in both eyes in the LAMP phase 1 study were continued in this extended trial (phase 2). Children in the placebo group (phase 1) were switched to receive 0.05% atropine from the beginning of the second-year follow-up, whereas those in the 0.05%, 0.025%, and 0.01% atropine groups continued with the same regimen. Cycloplegic refraction, axial length (AL), accommodation amplitude, photopic and mesopic pupil diameter, and best-corrected visual acuity were measured at 4-month intervals. Changes in spherical equivalent (SE) and AL and their differences between groups. Over the 2-year period, the mean SE progression was 0.55±0.86 D, 0.85±0.73 D, and 1.12±0.85 D in the 0.05%, 0.025%, and 0.01% atropine groups, respectively (P= 0.015, P < 0.001, and P= 0.02, respectively, for pairwise comparisons), with mean AL changes over 2 years of 0.39±0.35 mm, 0.50±0.33 mm, and 0.59±0.38 mm (P= 0.04, P < 0.001, and P= 0.10, respectively). Compared with the first year, the second-year efficacy of 0.05% and 0.025% atropine remained similar (P>0.1), but improved mildly in the 0.01% atropine group (P= 0.04). For the phase 1 placebo group, the myopia progression was reduced significantly after switching to 0.05% atropine (SE change, 0.18 D in second year vs. 0.82 D in first year [P < 0.001]; AL elongated 0.15 mm in second year vs. 0.43 mm in first year [P < 0.001]). Accommodation loss and change in pupil size in all concentrations remained similar to the first-year results and were well tolerated. Visual acuity and vision-related quality of life remained unaffected. Over 2 years, the efficacy of 0.05% atropine observed was double that observed with 0.01% atropine, and it remained the optimal concentration among the studied atropine concentrations in slowing myopia progression.

Generational Difference of Axial Length and Its Risk Factors in Urban and Rural China.

Purpose To compare the axial length difference (ALD) and the estimated generational axial length shift (ALS) from parents to their children and its risk factors in urban and rural China. Methods Participants were enrolled from two longitudinal cohort studies, the Beijing Myopia Progression Study (BMPS) and the Handan Offspring Myopia Study (HOMS). Ocular biometry was performed in both parents and their children. ALD was defined as the difference between the children's axial length and the corresponding parental axial length. Generational ALS was estimated according to a binominal prediction model at 18 years of age. Results 237 and 380 urban and rural Chinese children (6–17 years) and their parents from the BMPS and HOMS, respectively, were enrolled. Children's axial length was estimated to be closest to the parental axial length at 11 and 9 years of age in the urban and rural areas, respectively; the estimated generational ALS would be 1.53 and 0.57 mm, respectively. Multivariable regression analysis revealed that older children (urban β = 0.26, p < 0.001; rural β = 0.11, p < 0.001) and males had larger ALD (urban β = 0.55, p < 0.001; rural β = 0.52, p < 0.001) in both areas. Furthermore, urban children with more educated parents (fathers: β = −0.30, p=0.002; mothers: β = −0.29, p=0.004) and more outdoor activity (β = −0.23, p=0.006) had a less ALD. Conclusions The urban generational axial length shift was estimated to be approximately 1 mm longer than that of the rural area. These results suggest different environmental effects on the ocular development in these two populations of Chinese children.

The Impact of Parental Rural-to-urban Migration on Children’s Refractive Error in Rural China: A Propensity Score Matching Analysis

ABSTRACTPurpose: Parental rural-to-urban migration has a wide range of health effects on children’s but its impact on children’s refractive status remains unclear. We aim to examine whether parental rural-to-urban migration could influence the refractive status of their children in rural areas of China.Methods: Among the 2346 grade 7 students in the Mojiang Myopia Progression Study, information regarding parental migration was collected by questionnaires and was successfully obtained in 2105 participants. Refractive error was measured in diopters (D) with cycloplegia using an autorefractor and axial length (AL) was measured using an IOL Master. One-to-one nearest-neighbor matching techniques with a 0.01 caliper level were used to estimate the propensity score matching (PSM) models.Results: Among all the participants, 472 pairs (1 student with vs. 1 student without migrant parents) were successfully matched based on propensity scores. Students with migrant parents had a lower proportion of myopia (29.2% vs. 40.7%; P < .001) and more hyperopic refractions (−0.25D vs. −0.31D; P = .04) compared with those without. They also had shorter ALs (23.4 mm vs. 23.6 mm) but the difference was not significance (P = .18). In addition, students with migrant parents spent less time reading after school per day (0.87 vs. 1.01 hours; P = .01).Conclusions: Myopia is less prevalent among children with migrant parents compared with those without. This study indicated that living without parents might be a protect factor for myopia in Chinese school student via giving them less pressure on study.