Trial Outcomes & Findings for Effects of Blue-light Blocking Lens on Visual Functions (NCT NCT02821403)

Last Updated: 2017-04-07

Results Overview

Contrast sensitivity was measured using the Mars contrast sensitivity letter chart (Mars Perceptrix, Chappaqua, NY). One out of three charts differing in the letter combinations was selected randomly in order to avoid memorization of the charts. The chart was placed at 50 cm with each letter subtended 2° visual angle. We followed the recording procedures as specified by the manufacturer: participants were instructed to read the letters from high to low contrasts and the test ended when two consecutive errors were made. The contrast sensitivity was scored as the log contrast sensitivity of the last correct letter minus 0.04 log unit for every prior error. The test was administered under normal (room illumination, 400 lux) and glare conditions. A brightness acuity tester set at its medium light intensity level (100 foot lamberts) simulated the glaring condition. A higher mean indicates improved contrast sensitivity.

Recruitment status

COMPLETED

Study phase

Target enrollment

80 participants

Primary outcome timeframe

Every 1-month interval from the date of randomization, up to 3 months

Results posted on

2017-04-07

Participant Flow

Participant milestones

Participant milestones
Measure	Young Adults adults without presbyopia who aged 18-35 years Three types of spectacle lenses were given to all participants: 1) clear lens with regular coating; 2) regular coating lens with yellow tint; 3) clear lens with blue-light blocking coating. Cross-over study design: The sequence of lens types was pseudo-randomized for each individual, i.e., participants were allocated in different sequences of lens wear by the date of admission.	Middle-aged Adults adults with presbyopia who aged over 40 years Three types of spectacle lenses were given to all participants: 1) clear lens with regular coating; 2) regular coating lens with yellow tint; 3) clear lens with blue-light blocking coating. Cross-over study design: The sequence of lens types was pseudo-randomized for each individual, i.e., participants were allocated in different sequences of lens wear by the date of admission.
"First Intervention (1 Month)" STARTED	40	40
"First Intervention (1 Month)" Used Clear Lens	13	13
"First Intervention (1 Month)" Used Yellow Tinted Lens	13	14
"First Intervention (1 Month)" Used Blue-filtering Coated Lens	14	13
"First Intervention (1 Month)" COMPLETED	40	40
"First Intervention (1 Month)" NOT COMPLETED	0	0
"Second Intervention (1 Month)" STARTED	40	40
"Second Intervention (1 Month)" Used Clear Lens	13	14
"Second Intervention (1 Month)" Used Yellow Tinted Lens	14	13
"Second Intervention (1 Month)" Used Blue-filtering Coated Lens	13	13
"Second Intervention (1 Month)" COMPLETED	40	40
"Second Intervention (1 Month)" NOT COMPLETED	0	0
"Third Intervention (1 Month)" STARTED	40	40
"Third Intervention (1 Month)" Used Clear Lens	14	13
"Third Intervention (1 Month)" Used Yellow Tinted Lens	13	13
"Third Intervention (1 Month)" Used Blue-filtering Coated Lens	13	14
"Third Intervention (1 Month)" COMPLETED	40	40
"Third Intervention (1 Month)" NOT COMPLETED	0	0

Reasons for withdrawal

Withdrawal data not reported

Baseline Characteristics

Effects of Blue-light Blocking Lens on Visual Functions

Baseline characteristics by cohort

Baseline characteristics by cohort
Measure	Young Adults n=40 Participants adults without presbyopia who aged 18-35 years Three spectacle lens designs: 1) clear lens with regular coating; 2) regular coating lens with yellow tint; 3) clear lens with blue-light blocking coating: 3 types of spectacle lenses were given to all participants: 1) clear lens with regular coating; 2) regular coating lens with yellow tint; 3) clear lens with blue-light blocking coating	Middle-aged Adults n=40 Participants adults with presbyopia who aged over 40 years Three spectacle lens designs: 1) clear lens with regular coating; 2) regular coating lens with yellow tint; 3) clear lens with blue-light blocking coating: 3 types of spectacle lenses were given to all participants: 1) clear lens with regular coating; 2) regular coating lens with yellow tint; 3) clear lens with blue-light blocking coating	Total n=80 Participants Total of all reporting groups
Age, Categorical <=18 years	0 Participants n=5 Participants	0 Participants n=7 Participants	0 Participants n=5 Participants
Age, Categorical Between 18 and 65 years	40 Participants n=5 Participants	40 Participants n=7 Participants	80 Participants n=5 Participants
Age, Categorical >=65 years	0 Participants n=5 Participants	0 Participants n=7 Participants	0 Participants n=5 Participants
Sex: Female, Male Female	21 Participants n=5 Participants	29 Participants n=7 Participants	50 Participants n=5 Participants
Sex: Female, Male Male	19 Participants n=5 Participants	11 Participants n=7 Participants	30 Participants n=5 Participants

PRIMARY outcome

Timeframe: Every 1-month interval from the date of randomization, up to 3 months

Outcome measures

Outcome measures
Measure	Young Adults: Clear Lens With Regular Coating n=40 Participants adults without presbyopia who aged 18-35 years Three types of spectacle lenses were given to all participants: 1) clear lens with regular coating; 2) regular coating lens with yellow tint; 3) clear lens with blue-light blocking coating. The sequence of lens types was pseudo-randomized for each individual, i.e., participants were allocated in different sequences of lens wear by the date of admission.	Young Adults: Regular Coating Lens With Yellow Tint n=40 Participants adults without presbyopia who aged 18-35 years Three types of spectacle lenses were given to all participants: 1) clear lens with regular coating; 2) regular coating lens with yellow tint; 3) clear lens with blue-light blocking coating. The sequence of lens types was pseudo-randomized for each individual, i.e., participants were allocated in different sequences of lens wear by the date of admission.	Young Adults: Clear Lens With Blue-light Blocking Coating n=40 Participants adults without presbyopia who aged 18-35 years Three types of spectacle lenses were given to all participants: 1) clear lens with regular coating; 2) regular coating lens with yellow tint; 3) clear lens with blue-light blocking coating. The sequence of lens types was pseudo-randomized for each individual, i.e., participants were allocated in different sequences of lens wear by the date of admission.	Middle-aged Adults: Clear Lens With Regular Coating n=40 Participants adults with presbyopia who aged over 40 years Three types of spectacle lenses were given to all participants: 1) clear lens with regular coating; 2) regular coating lens with yellow tint; 3) clear lens with blue-light blocking coating. The sequence of lens types was pseudo-randomized for each individual, i.e., participants were allocated in different sequences of lens wear by the date of admission.	Middle-aged Adults: Regular Coating Lens With Yellow Tint n=40 Participants adults with presbyopia who aged over 40 years Three types of spectacle lenses were given to all participants: 1) clear lens with regular coating; 2) regular coating lens with yellow tint; 3) clear lens with blue-light blocking coating. The sequence of lens types was pseudo-randomized for each individual, i.e., participants were allocated in different sequences of lens wear by the date of admission.	Middle-aged Adults: Clear Lens With Blue-light Blocking Coatin n=40 Participants adults with presbyopia who aged over 40 years Three types of spectacle lenses were given to all participants: 1) clear lens with regular coating; 2) regular coating lens with yellow tint; 3) clear lens with blue-light blocking coating. The sequence of lens types was pseudo-randomized for each individual, i.e., participants were allocated in different sequences of lens wear by the date of admission.
Contrast Sensitivity as Assessed by Mars Contrast Sensitivity Chart without glare	1.866 log contrast sensitivity score Standard Error 0.004	1.861 log contrast sensitivity score Standard Error 0.005	1.856 log contrast sensitivity score Standard Error 0.008	1.818 log contrast sensitivity score Standard Error 0.014	1.799 log contrast sensitivity score Standard Error 0.016	1.802 log contrast sensitivity score Standard Error 0.013
Contrast Sensitivity as Assessed by Mars Contrast Sensitivity Chart with glare	1.817 log contrast sensitivity score Standard Error 0.015	1.802 log contrast sensitivity score Standard Error 0.032	1.777 log contrast sensitivity score Standard Error 0.035	1.759 log contrast sensitivity score Standard Error 0.019	1.768 log contrast sensitivity score Standard Error 0.018	1.785 log contrast sensitivity score Standard Error 0.017

PRIMARY outcome

Timeframe: Every 1-month interval from the date of randomization, up to 3 months

The Farnsworth Munsell 100 hue test (X-Rite, USA) was used to evaluate colour vision. Each of the four trays consisted of 21 movable caps. Participants were asked to sort the randomly arranged caps following the hue order from the first to the last fixed caps. The total error score was calculated, as documented in the instruction manual, to quantify the accuracy of color discrimination. There are no defined endpoints to the "total error score" range. A lower score indicates improved color discrimination ability.

Outcome measures

Outcome measures
Measure	Young Adults: Clear Lens With Regular Coating n=40 Participants adults without presbyopia who aged 18-35 years Three types of spectacle lenses were given to all participants: 1) clear lens with regular coating; 2) regular coating lens with yellow tint; 3) clear lens with blue-light blocking coating. The sequence of lens types was pseudo-randomized for each individual, i.e., participants were allocated in different sequences of lens wear by the date of admission.	Young Adults: Regular Coating Lens With Yellow Tint n=40 Participants adults without presbyopia who aged 18-35 years Three types of spectacle lenses were given to all participants: 1) clear lens with regular coating; 2) regular coating lens with yellow tint; 3) clear lens with blue-light blocking coating. The sequence of lens types was pseudo-randomized for each individual, i.e., participants were allocated in different sequences of lens wear by the date of admission.	Young Adults: Clear Lens With Blue-light Blocking Coating n=40 Participants adults without presbyopia who aged 18-35 years Three types of spectacle lenses were given to all participants: 1) clear lens with regular coating; 2) regular coating lens with yellow tint; 3) clear lens with blue-light blocking coating. The sequence of lens types was pseudo-randomized for each individual, i.e., participants were allocated in different sequences of lens wear by the date of admission.	Middle-aged Adults: Clear Lens With Regular Coating n=40 Participants adults with presbyopia who aged over 40 years Three types of spectacle lenses were given to all participants: 1) clear lens with regular coating; 2) regular coating lens with yellow tint; 3) clear lens with blue-light blocking coating. The sequence of lens types was pseudo-randomized for each individual, i.e., participants were allocated in different sequences of lens wear by the date of admission.	Middle-aged Adults: Regular Coating Lens With Yellow Tint n=40 Participants adults with presbyopia who aged over 40 years Three types of spectacle lenses were given to all participants: 1) clear lens with regular coating; 2) regular coating lens with yellow tint; 3) clear lens with blue-light blocking coating. The sequence of lens types was pseudo-randomized for each individual, i.e., participants were allocated in different sequences of lens wear by the date of admission.	Middle-aged Adults: Clear Lens With Blue-light Blocking Coatin n=40 Participants adults with presbyopia who aged over 40 years Three types of spectacle lenses were given to all participants: 1) clear lens with regular coating; 2) regular coating lens with yellow tint; 3) clear lens with blue-light blocking coating. The sequence of lens types was pseudo-randomized for each individual, i.e., participants were allocated in different sequences of lens wear by the date of admission.
Color Vision as Assessed by the Farnsworth Munsell 100 Hue Test	30.8 units on a scale Standard Error 3.34	33.3 units on a scale Standard Error 3.36	30.1 units on a scale Standard Error 3.00	49.1 units on a scale Standard Error 5.49	54.65 units on a scale Standard Error 4.66	52.4 units on a scale Standard Error 5.21

SECONDARY outcome

Timeframe: Every 1-month interval from the date of randomization, up to 3 months

After each monthly wearing period (visits 3-5), the participants' lens performance, night vision quality and sleep quality (total 13 questions) were assessed subjectively using a questionnaire (scoring from 1 \[very unsatisfactory\] to 5 \[very satisfactory\]). At the end of the study, the participants were asked to choose their preferred lens type among the three pairs of lenses based on their subjective feeling of the "best lens type" (i.e., either clear lens, yellow tinted lens or blue-filtering coated lens). To make it clear and simple, here we only present the data on the participants choice of their preferred lens type (i.e., simply choosing the "best lens" among clear lens, yellow tinted lens or blue-filtering coated lens).

Outcome measures

Outcome measures
Measure	Young Adults: Clear Lens With Regular Coating n=40 Participants adults without presbyopia who aged 18-35 years Three types of spectacle lenses were given to all participants: 1) clear lens with regular coating; 2) regular coating lens with yellow tint; 3) clear lens with blue-light blocking coating. The sequence of lens types was pseudo-randomized for each individual, i.e., participants were allocated in different sequences of lens wear by the date of admission.	Young Adults: Regular Coating Lens With Yellow Tint n=40 Participants adults without presbyopia who aged 18-35 years Three types of spectacle lenses were given to all participants: 1) clear lens with regular coating; 2) regular coating lens with yellow tint; 3) clear lens with blue-light blocking coating. The sequence of lens types was pseudo-randomized for each individual, i.e., participants were allocated in different sequences of lens wear by the date of admission.	Young Adults: Clear Lens With Blue-light Blocking Coating adults without presbyopia who aged 18-35 years Three types of spectacle lenses were given to all participants: 1) clear lens with regular coating; 2) regular coating lens with yellow tint; 3) clear lens with blue-light blocking coating. The sequence of lens types was pseudo-randomized for each individual, i.e., participants were allocated in different sequences of lens wear by the date of admission.	Middle-aged Adults: Clear Lens With Regular Coating adults with presbyopia who aged over 40 years Three types of spectacle lenses were given to all participants: 1) clear lens with regular coating; 2) regular coating lens with yellow tint; 3) clear lens with blue-light blocking coating. The sequence of lens types was pseudo-randomized for each individual, i.e., participants were allocated in different sequences of lens wear by the date of admission.	Middle-aged Adults: Regular Coating Lens With Yellow Tint adults with presbyopia who aged over 40 years Three types of spectacle lenses were given to all participants: 1) clear lens with regular coating; 2) regular coating lens with yellow tint; 3) clear lens with blue-light blocking coating. The sequence of lens types was pseudo-randomized for each individual, i.e., participants were allocated in different sequences of lens wear by the date of admission.	Middle-aged Adults: Clear Lens With Blue-light Blocking Coatin adults with presbyopia who aged over 40 years Three types of spectacle lenses were given to all participants: 1) clear lens with regular coating; 2) regular coating lens with yellow tint; 3) clear lens with blue-light blocking coating. The sequence of lens types was pseudo-randomized for each individual, i.e., participants were allocated in different sequences of lens wear by the date of admission.
Self-assessment of Lens Performance Through Questionnaire clear lens with regular coating	20 Participants	9 Participants	—	—	—	—
Self-assessment of Lens Performance Through Questionnaire regular coating lens with yellow tint	1 Participants	7 Participants	—	—	—	—
Self-assessment of Lens Performance Through Questionnaire clear lens with blue-light blocking coating	19 Participants	24 Participants	—	—	—	—

Adverse Events

Young Adults

Serious events: 0 serious events

Other events: 0 other events

Deaths: 0 deaths

Middle-aged Adults

Serious events: 0 serious events

Other events: 0 other events

Deaths: 0 deaths

Serious adverse events

Adverse event data not reported

Other adverse events

Adverse event data not reported

Additional Information

Dr. Tsz Wing Leung

The Hong Kong Polytechnic University

Phone: 27664268

Email: [email protected]

Results disclosure agreements

Principal investigator is a sponsor employee
Publication restrictions are in place