The Effect of Cataract on Photoentrainment of the Circadian Rhythm in Humans

Cataract Clinical Trial

— CIRCAT  

Official title:

The Effect of Cataract on Photoentrainment of the Circadian Rhythm in Humans

Clinical Trial Details — Status: Completed

Administrative data

• NCT number: NCT01686308
• Other study ID #: CIRCAT
• Status: Completed
• Phase: N/A
• First received: November 30, 2011
• Last updated: February 9, 2015
• Start date: February 2011
• Est. completion date: December 2014

Study information

• Verified date: February 2015
• Source: Glostrup University Hospital, Copenhagen
• Contact: n/a
• Is FDA regulated: No
• Health authority: Denmark: Ethics Committee
• Study type: Interventional

Clinical Trial Summary

Cataract is globally the most common cause of blindness and in Denmark the operation with - 50.000 treatments per year - is the most common eye operation. The cause of cataract is growth and denaturation of the lens proteins. This leads to an increased absorption of blue light and increased light scatter. This may affect newly discovered cells in the retina that are involved in the regulation of the circadian rhythm. When the internal circadian rhythm is not synchronized with the external day and night a phase-shift occurs. Most people know of this discomfort as jet-lag, but the consequences may be much more severe such as heighten risk of cancer and cardiovascular disease.

The goal of this project is to study how the circadian regulating cells of the retina is affected by cataract and by the operation. Cataract patients are studied before and after the operation with questionnaires, hormone and activity measurements and with a specialized pupil measurement that measures the indirect response of the circadian regulating cells to blue light.

Results from this study aim to shed light on the regulatory mechanisms of the eye on the circadian rhythm and how these are affected by cataract. Furthermore, choice of intraocular lens is evaluated. This may have impact on clinical practise especially with regard to choice of intraocular lens and widened indications for cataract surgery.

Recruitment information / eligibility

• Status: Completed
• Enrollment: 76
• Est. completion date: December 2014
• Est. primary completion date: December 2014
• Accepts healthy volunteers: No
• Gender: Both
• Age group: 18 Years and older

Eligibility

Inclusion Criteria:

• Age related/senile bilateral cataract

• Eligible for phaco-emulsification on both eyes

Exclusion Criteria:

• Known eye disease other than cataract.

• Known systemic disease, which may affect the retina (untreated hypertension, DM etc.)

• Known systemic disease, which may affect the lens.

• Known psychiatric disease.

• Known sleep or circadian rhythm disorder, not caused by lowered blue light transmission by the lens.

• Per- and post operative complications

• Use of drugs that may affect the sleep.

For a subpopulation also:

• Poor cooperation.

• Severe refraction abnormalities.

• Previous eye surgery

• Nystagmus

• Congenital or acquired abnormalities of: eye lids and eye area, cornea or iris.

• Use of medicine that may affect the pupillary response.

• Use of drugs that may affect the pupillary response.

Study Design

Allocation: Randomized, Intervention Model: Parallel Assignment, Masking: Double Blind (Subject, Investigator), Primary Purpose: Treatment

Related Conditions & MeSH terms

• Cataract

Intervention

Procedure:
• Yellow Intra Ocular Lens (IOL)
Standard operation with blue light filter Yellow IOL implantation
• Conventional Intra Ocular Lens (IOL)
Standard operation with conventional IOL implantation

Locations

Country	Name	City	State
Denmark	Glostrup University Hospital	Glostrup

Sponsors (1)

Lead Sponsor	Collaborator
Glostrup University Hospital, Copenhagen

Country where clinical trial is conducted

Denmark, 

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	Pupillary response to blue light	Measurement of the consensual light response to red (630 nm) and blue (470 nm)	1 year/1month	No
Secondary	Questionnaire	Pittsburgh Sleep Quality Index and the Morningness Eveningness Questionnaire	1year/1month	No
Secondary	Questionnaire	Morningness-eveningness questionnaire	1 year/1 month	No
Secondary	Melatonin day variety analysis	Salivary samples collected with 4 hour interval during 24 hours. Analyzed for melatonin concentration with Radio Immuno Assay (RIA).	1year/1month	No
Secondary	Actigraphy	Activity measured during 7 days and 7 nights with the Spectrum Actiwatch, Respironics, Philips	1year/1month	No