Myopia, Myopia Progressing
Conditions
Keywords
Myopia Progression, Branched-chain amino acids, Nutritional supplementation, Randomized controlled trial, Axial length, OCTA
Brief summary
This study is a randomized controlled trial designed to evaluate whether branched-chain amino acid (BCAA) supplementation can help slow the progression of myopia in young adults. Eligible participants will be randomly assigned to receive either BCAA supplementation combined with standard spectacle correction or standard spectacle correction with a matching placebo. The intervention period will last approximately six months. Participants will undergo regular follow-up examinations, including measurements of visual acuity, refractive error, axial length, intraocular pressure, and other ocular parameters. Additional assessments such as ocular imaging (including OCTA), physical examinations, and blood tests will also be performed to evaluate eye health and metabolic indicators. The main purpose of this study is to investigate whether BCAA supplementation can provide a safe and effective nutritional strategy to slow myopia progression and improve understanding of the relationship between amino acid metabolism and ocular growth.
Interventions
DIETARY_SUPPLEMENTBranched-Chain Amino Acids (BCAA) Supplementation
Participants will receive oral branched-chain amino acids (BCAA), including leucine, isoleucine, and valine, as a dietary supplement in addition to standard spectacle correction. The intervention is administered daily for approximately 6 months. The supplement is a commercially available nutritional product obtained via cross-border e-commerce channels and is not intended as a therapeutic drug. The aim is to evaluate the effect of BCAA supplementation on myopia progression and ocular biometric parameters.
Sponsors
Zhongda Hospital
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
PREVENTION
Masking
TRIPLE (Subject, Investigator, Outcomes Assessor)
Masking description
Ophthalmic examiners and personnel performing blood sample collection are also blinded to group assignment, although they are not involved in outcome evaluation.
Intervention model description
Participants will be randomly assigned in a parallel design to one of two groups: (1) spectacle correction (regular single-vision or myopia-control lenses) plus BCAA supplementation, or (2) spectacle correction (regular single-vision or myopia-control lenses) plus matched placebo supplementation. Both groups will be followed for approximately six months.
Eligibility
Sex/Gender
ALL
Age
18 Years to 25 Years
Healthy volunteers
Yes
Inclusion criteria
1. Healthy university students aged 18-25 years; 2. Spherical equivalent refraction (for eyes without prior corneal refractive surgery): SE ≤ -0.50 D; 3. Corrected visual acuity ≥ 0.8; 4. Corneal curvature 40 D-46 D; 5. Good compliance and ability to cooperate with follow-up and examinations; 6. Willingness and ability to participate in this study and sign the informed consent form.
Exclusion criteria
1. Strabismus, amblyopia, or other pathological ocular changes; 2. Systemic diseases affecting refractive development and allergic constitution, such as diabetes, metabolic syndrome, etc.; 3. Active eye disease or history of ophthalmic surgery; 4. Use of orthokeratology lenses or other myopia-control interventions within the past 6 months; 5. Use of BCAA-related supplements within the past 6 months, or serum BCAA levels outside the reference range; 6. Considered by the responsible physician to be unable to participate or unable to comply with the study requirements; 7. Abnormal liver or kidney function.
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Change in axial length | Baseline to 6 months | Axial length (AL) will be measured in both eyes using optical biometry at baseline, 3 months, and 6 months. The primary outcome is the change in axial length from baseline to 6 months, comparing the BCAA supplementation plus spectacle correction group with the spectacle correction only group. |
| Change in spherical equivalent refractive error | Baseline to 6 months | Cycloplegic spherical equivalent (SE) will be measured using autorefractometry under cycloplegia at baseline, 3 months, and 6 months. The primary outcome is the change in spherical equivalent refractive error from baseline to 6 months, comparing the BCAA supplementation group with the control group. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Superficial retinal vessel density | Baseline and 6 months | Superficial retinal vessel density will be measured in both eyes using OCTA in foveal, parafoveal, and perifoveal regions. Sectoral measurements (temporal, superior, nasal, and inferior) will be obtained, and the final value will be calculated as the mean of all regions, reported as a percentage (%). |
| Deep retinal vessel density | Baseline and 6 months | Deep retinal vessel density will be measured in both eyes using OCTA across ETDRS regions. Sectoral measurements will be obtained, and the final value will be calculated as the mean of all regions, reported as a percentage (%). |
| Choriocapillaris perfusion density | Baseline and 6 months | Choriocapillaris perfusion will be measured in both eyes using OCTA across foveal, parafoveal, and perifoveal regions. Sectoral measurements will be obtained, and the final value will be calculated as the mean of all regions, reported as a percentage (%). |
| Retinal perfusion density | Baseline and 6 months | Retinal perfusion density will be measured in both eyes using OCTA across ETDRS regions, including full retinal perfusion and large-vessel-excluded perfusion. Sectoral measurements will be obtained, and the final value will be calculated as the mean of all regions, reported as a percentage (%). |
| Family Ocular History | Baseline | Definition: Baseline refractive status of parents based on self-reported highest degree of myopia in either eye. Variable type: Categorical Measurement: Self-reported parental myopia status categorized as none, low (≤300°), moderate (300-600°), and high (≥600°). |
| Nutritional Supplement Use | Baseline | Definition: Baseline information on participants' use of any nutritional or dietary supplements. Variable type: Binary (Yes/No) Measurement: Self-reported use of dietary or nutritional supplements (Yes/No). |
| Protein Allergy History | Baseline | Definition: Baseline assessment of whether participants have a documented or self-reported history of protein allergy. Variable type: Binary (Yes/No) Measurement: Self-reported history of protein allergy (Yes/No). |
| Parental Education Level | Baseline | Parental education level at baseline, self-reported via structured questionnaire. Education levels are categorized as: primary school or below, junior/high school, university, and master's degree or above.Variable Type：Categorical |
| Daily Screen Time | Baseline | Average daily time spent using electronic devices (including television, mobile phone, computer, and projection screen) over the past week, assessed by questionnaire. Variable type: Categorical. |
| Eye Rest and Break Behavior | Baseline | Definition: Frequency of eye breaks during near work activities. Variable type: Categorical Measurement: Self-reported duration of continuous near work before rest (≤30 min, 30-60 min, 1-2 h, 2-3 h, ≥3 h). |
| Sleep Duration | Baseline | Definition: Average daily sleep duration over the past week. Variable type: Continuous Measurement: Self-reported average sleep time (hours and minutes per day). |
| Staple food intake frequency | Baseline | Frequency and quantity of staple food intake, including rice, wheat-based products, corn products, mixed beans, tubers, and fried flour-based foods, assessed using a semi-quantitative food frequency questionnaire. |
| Protein-rich food intake frequency | Baseline | Frequency and quantity of protein-rich food consumption, including soybeans and soy products, meat (pork, beef, lamb, poultry), aquatic products (fish, shrimp, shellfish), eggs, and dairy products, assessed using a semi-quantitative food frequency questionnaire. |
| Vegetable intake frequency | Baseline | Frequency and quantity of vegetable intake, including dark green vegetables, red/orange vegetables, purple vegetables, and light-colored vegetables, assessed using a semi-quantitative food frequency questionnaire. |
| Fruit intake frequency | Baseline | Frequency and quantity of fruit intake, including pome fruits, citrus fruits, stone fruits, berries, melons, and tropical fruits, assessed using a semi-quantitative food frequency questionnaire. |
| Dairy product intake frequency | Baseline | Frequency and quantity of dairy product consumption, including liquid milk, milk powder, and yogurt, assessed using a semi-quantitative food frequency questionnaire. |
| Snack and sugary food intake frequency | Baseline | Frequency and quantity of intake of snacks and sugary foods, including baked goods, nuts, processed snacks, sweets, and sugar-sweetened beverages, assessed using a semi-quantitative food frequency questionnaire. |
| Temporal Superior RNFL Thickness | Baseline and 6 months | Peripapillary retinal nerve fiber layer (RNFL) thickness in the temporal superior (TU) sector measured by optical coherence tomography angiography (OCTA), reported in micrometers (µm). |
| Superior Temporal RNFL Thickness | Baseline and 6 months | Peripapillary RNFL thickness in the superior temporal (ST) sector measured by OCTA, reported in micrometers (µm). |
| Superior Nasal RNFL Thickness | Baseline and 6 months | Peripapillary RNFL thickness in the superior nasal (SN) sector measured by OCTA, reported in micrometers (µm). |
| Nasal Superior RNFL Thickness | Baseline and 6 months | Peripapillary RNFL thickness in the nasal superior (NU) sector measured by OCTA, reported in micrometers (µm). |
| Nasal Inferior RNFL Thickness | Baseline and 6 months | Peripapillary RNFL thickness in the nasal inferior (NL) sector measured by OCTA, reported in micrometers (µm). |
| Inferior Nasal RNFL Thickness | Baseline and 6 months | Peripapillary RNFL thickness in the inferior nasal (IN) sector measured by OCTA, reported in micrometers (µm). |
| Inferior Temporal RNFL Thickness | Baseline and 6 months | Peripapillary RNFL thickness in the inferior temporal (IT) sector measured by OCTA, reported in micrometers (µm). |
| Temporal Inferior RNFL Thickness | Baseline and 6 months | Peripapillary RNFL thickness in the temporal inferior (TL) sector measured by OCTA, reported in micrometers (µm). |
| Global Average Peripapillary RNFL Thickness | Baseline and 6 months | Global average peripapillary retinal nerve fiber layer (RNFL) thickness measured by optical coherence tomography angiography (OCTA), calculated as the mean thickness across all peripapillary regions, and reported in micrometers (µm). |
| Optic Disc Area | Baseline and 6 months | Optic disc area measured in both eyes using optical coherence tomography angiography (OCTA), reported in square millimeters (mm²). |
| Neuroretinal Rim Area | Baseline and 6 months | Neuroretinal rim area measured in both eyes using OCTA, reported in square millimeters (mm²). |
| Optic Cup Volume | Baseline and 6 months | Optic cup volume measured in both eyes using OCTA, reported in cubic millimeters (mm³). |
| Cup-to-Disc Ratio | Baseline and 6 months | Cup-to-disc ratio measured in both eyes using OCTA, defined as the ratio of optic cup diameter to optic disc diameter (unitless). |
| Vertical Cup-to-Disc Ratio | Baseline and 6 months | Vertical cup-to-disc ratio measured in both eyes using OCTA (unitless). |
| Horizontal Cup-to-Disc Ratio | Baseline and 6 months | Horizontal cup-to-disc ratio measured in both eyes using OCTA (unitless). |
| Peripapillary Temporal Superior Sector Vessel Density | Baseline and 6 months | Peripapillary microvascular vessel density in the temporal superior (TU) sector measured in both eyes using optical coherence tomography angiography (OCTA), reported as vessel density percentage (%). |
| Peripapillary Superior Temporal Sector Vessel Density | Baseline and 6 months | OCTA-derived vessel density in the superior temporal (ST) peripapillary sector in both eyes,reported as vessel density percentage (%). |
| Peripapillary Superior Nasal Sector Vessel Density | Baseline and 6 months | OCTA-derived vessel density in the superior nasal (SN) peripapillary sector in both eyes,reported as vessel density percentage (%). |
| Peripapillary Nasal Superior Sector Vessel Density | Baseline and 6 months | OCTA-derived vessel density in the nasal superior (NU) peripapillary sector in both eyes,reported as vessel density percentage (%). |
| Peripapillary Nasal Inferior Sector Vessel Density | Baseline and 6 months | OCTA-derived vessel density in the nasal inferior (NL) peripapillary sector in both eyes, |
| Peripapillary Inferior Nasal Sector Vessel Density | Baseline and 6 months | OCTA-derived vessel density in the inferior nasal (IN) peripapillary sector in both eyes,reported as vessel density percentage (%). |
| Peripapillary Inferior Temporal Sector Vessel Density | Baseline and 6 months | OCTA-derived vessel density in the inferior temporal (IT) peripapillary sector in both eyes,reported as vessel density percentage (%). |
| Peripapillary Temporal Inferior Sector Vessel Density | Baseline and 6 months | OCTA-derived vessel density in the temporal inferior (TL) peripapillary sector in both eyes,reported as vessel density percentage (%). |
| Global Peripapillary Vessel Density | Baseline and 6 months | Mean peripapillary microvascular vessel density calculated across all peripapillary sectors in both eyes using OCTA,reported as vessel density percentage (%). |
| Full Macular Retinal Thickness | Baseline and 6 months | Full retinal thickness in the macular region measured in both eyes using optical coherence tomography angiography (OCTA), including foveal, parafoveal, and perifoveal regions across temporal, superior, nasal, and inferior sectors. |
| Macular Inner Retinal Layer Thickness | Baseline and 6 months | Inner retinal layer thickness in the macular region measured in both eyes using OCTA, assessed at foveal, parafoveal, and perifoveal regions across four quadrants (temporal, superior, nasal, inferior). |
| Macular Outer Retinal Layer Thickness | Baseline and 6 months | Outer retinal layer thickness in the macular region measured in both eyes using OCTA, including foveal, parafoveal, and perifoveal regions across temporal, superior, nasal, and inferior sectors. |
| Foveal Avascular Zone Area | Baseline and 6 months | Foveal avascular zone (FAZ) area measured in both eyes using optical coherence tomography angiography (OCTA). |
| FAZ-300 Superficial Capillary Plexus Perfusion Density | Baseline and 6 months | Perfusion density in a 300 μm annular region surrounding the FAZ in the superficial capillary plexus measured using OCTA. |
| FAZ-300 Deep Capillary Plexus Perfusion Density | Baseline and 6 months | Perfusion density in a 300 μm annular region surrounding the FAZ in the deep capillary plexus measured using OCTA. |
| FAZ-300 Full Retinal Perfusion Density | Baseline and 6 months | Perfusion density in a 300 μm annular region surrounding the FAZ across full retinal layers measured using OCTA. |
| Alanine Aminotransferase (ALT) | Baseline and 6 months | Serum alanine aminotransferase (ALT) measured in fasting venous blood using standard laboratory methods. Values will be analyzed as continuous variables and categorized as normal or abnormal based on clinical reference ranges. |
| Aspartate Aminotransferase (AST) | Baseline and 6 months | Serum AST measured using standard laboratory methods in fasting venous blood. Values will be analyzed as continuous variables and categorized as normal or abnormal based on clinical reference ranges. |
| Total Bilirubin (TBil) | Baseline and 6 months | Serum total bilirubin measured in fasting venous blood. Values will be analyzed as continuous variables and categorized as normal or abnormal based on clinical reference ranges. |
| Serum Creatinine (Scr) | Baseline and 6 months | Serum creatinine measured in fasting venous blood using standard laboratory methods. Values will be analyzed as continuous variables and categorized as normal or abnormal based on clinical reference ranges. |
| Blood Urea Nitrogen (BUN) | Baseline and 6 months | BUN measured in fasting venous blood using standard laboratory methods. Values will be analyzed as continuous variables and categorized as normal or abnormal based on clinical reference ranges. |
| Uric Acid (UA) | Baseline and 6 months | Serum uric acid measured in fasting venous blood using standard laboratory methods. Values will be analyzed as continuous variables and categorized as normal or abnormal based on clinical reference ranges. |
| Fasting Plasma Glucose (FPG) | Baseline and 6 months | Fasting plasma glucose measured in fasting venous blood using standard laboratory methods. Values will be analyzed as continuous variables and categorized as normal or abnormal based on clinical reference ranges. |
| Total Cholesterol (TC) | Baseline and 6 months | Serum total cholesterol measured in fasting venous blood using standard laboratory methods. Values will be analyzed as continuous variables and categorized as normal or abnormal based on clinical reference ranges. |
| Triglycerides (TG) | Baseline and 6 months | Serum triglycerides measured in fasting venous blood using standard laboratory methods. Values will be analyzed as continuous variables and categorized as normal or abnormal based on clinical reference ranges. |
| High-Density Lipoprotein Cholesterol (HDL-C) | Baseline and 6 months | HDL cholesterol measured in fasting venous blood using standard laboratory methods. Values will be analyzed as continuous variables and categorized as normal or abnormal based on clinical reference ranges. |
| Low-Density Lipoprotein Cholesterol (LDL-C) | Baseline and 6 months | LDL cholesterol measured in fasting venous blood using standard laboratory methods. Values will be analyzed as continuous variables and categorized as normal or abnormal based on clinical reference ranges. |
| Sex of Participants | Baseline | Participant sex recorded at baseline using structured questionnaire. |
| Age of Participants | Baseline | Age calculated from date of birth at baseline using structured questionnaire. |
| Ethnicity of Participants | Baseline | Ethnicity recorded at baseline using structured questionnaire. |
| Body Mass Index (BMI) | Baseline | BMI calculated from weight and height measured at baseline.Units：kg/m², Type：Continuous |
| Household Residence | Baseline | Household residence (urban/rural) recorded at baseline using structured questionnaire.Type：Categorical |
| Annual Household Income | Baseline | Annual household income recorded at baseline using structured questionnaire.Type : categorical |
| Study Pressure Level | Baseline | Self-reported level of study pressure and workload, assessed by questionnaire with four levels ranging from low to high. Variable type: Categorical. |
| Unhealthy Visual Habits | Baseline | Presence of unhealthy visual habits (e.g., reading under strong sunlight, using screens in dark environments, improper posture during near work), assessed by multiple-choice questionnaire. Variable type: Categorical (multiple response). |
| Lighting Conditions During Nighttime Near Work | Baseline | Lighting conditions used during near-work activities after dark (e.g., desk lamp, ceiling light), assessed by questionnaire. Variable type: Categorical. |
| Moderate-to-Vigorous Physical Activity Duration | Baseline | Average daily duration of moderate-to-vigorous physical activity (e.g., brisk walking, running, jumping rope, cycling) over the past week, assessed by questionnaire. Variable type: Categorical. |
Countries
China
Outcome results
None listed