{"type":"trials","record":{"id":87172,"source_id":"isrctn","external_id":"ISRCTN55089134","title":"The effect of the dietary antioxidant supplements lutein and zeaxanthin on retinal macular pigment optical density","brief_summary":"Dietary antioxidant supplements have been shown to have a beneficial effect on the clinical course of age-related macular degeneration (AMD), which is the commonest cause of blindness in the developed world. Of the various antioxidants, lutein (L) and zeaxanthin (Z) are of particular interest because of their biochemical, optical and anatomic properties. The aim is to assess the effect of a high-dose L and Z supplement on the concentration of these nutrients at the target tissue (the macula) in a large group of healthy monozygotic and dizygotic twins and to determine the heritability of MP augmentation/change in response to supplementation.","overall_status":"Completed","phases":[],"study_type":"Interventional","sponsor":"Guy's & St Thomas' NHS Trust (UK)","enrollment":322,"countries":["United Kingdom","England"],"start_date":"2004-03-07","completion_date":"2005-08-15","last_update_date":"2016-08-08","source_url":"https://www.isrctn.com/ISRCTN55089134","editorial_summary":"A registered study indexed because it matched monitored longevity research terms. Registry status: Completed. Registration does not establish safety or effectiveness.","first_seen_at":"2026-09-25T03:46:39.792962+00:00","last_seen_at":"2026-09-25T03:46:39.551+00:00","metadata":{"sex":"Female","age_range":"Adult","comparator":null,"attribution":"Source: ISRCTN ISRCTN55089134; retrieved 2026-09-25","interventions":["Supplement"],"reuse_license":"Registry contribution CC BY 4.0; generated metadata CC0","registry_source":"ISRCTN","outcome_measures":["Heritability of response to macular pigment supplement, measured using: 1. Reverse phase high performance liquid chroma…","1. Relationship between central retinal thickness and MPOD, measured using: 1.1. Optical coherence tomography to measur…"],"design_description":"Interventional","source_has_results":false},"controlled_terms":["Age-related macular degeneration (AMD)","All participants asked to take daily macular pigment supplement with food, “Macuvite” (Springfield®), consist…","results","Supplement"],"relevance_confidence":100,"source_quality_score":98,"freshness_score":35,"publication_state":"published","match_explanation":"Abstract contains controlled term: age-related macular degeneration.","quality_checked_at":"2026-09-25T03:46:42.633202+00:00","duplicate_cluster_key":"id:isrctn55089134","duplicate_of_id":null,"evidence_snapshot":{"status":"structured","version":1,"duration":"2004-03-07 to 2005-08-15","comparator":null,"confidence":"structured-source","population":"Female · Adult","provenance":{"duration":"start_date and completion_date","comparator":"registry arm fields","population":"registry eligibility fields","intervention":"registry intervention fields","participants":"enrollment","study_design":"study_type and registry design fields","evidence_stage":"phases","reported_outcome":"not available","outcomes_measured":"registry outcome-measure fields"},"generated_at":"2026-09-25T03:46:39.590Z","intervention":["Supplement"],"participants":322,"study_design":"Interventional","subject_scope":"Human clinical study registration","evidence_stage":"Phase not reported","safety_context":"Eligibility, adverse-event details, and clinical decisions must be checked in the official registry and with qualified clinicians.","source_support":"Structured registry protocol metadata; no finding-level conclusion is generated.","main_limitation":"This is a study registration. No reusable structured result is available here, so it cannot show whether the intervention worked or was safe.","reported_outcome":null,"outcomes_measured":["Heritability of response to macular pigment supplement, measured using: 1. Reverse phase high performance liquid chroma…","1. Relationship between central retinal thickness and MPOD, measured using: 1.1. Optical coherence tomography to measur…"],"regulatory_context":"Trial registration is not regulatory approval and does not establish that an intervention is available."},"clinical_trial_topics":[{"topic_slug":"vision-aging","is_published":true,"match_reasons":["Abstract contains controlled term: age-related macular degeneration.","Source terminology contains: age-related macular degeneration.","Abstract supplies longevity context: age-related.","Study type is explicitly identified as Interventional."],"matched_fields":["abstract","controlled terminology","abstract context","study type"],"relevance_score":100,"intelligence_topics":{"name":"Vision ageing","slug":"vision-aging"}}],"content_sources":{"name":"ISRCTN Registry","homepage_url":"https://www.isrctn.com/"}},"canonical_url":"https://www.immortal.life/trials/87172","automation_disclosure":"Generated automatically from cited source metadata. No scientist, clinician, researcher, editor, or human reviewer evaluates this publication before release."}