Nature and Frequency of Genetic Abnormalities and Associated Phenotypes in a Cohort of Adults With Intellectual Disability

NCT06630195 | Not Yet Recruiting

• 1 other identifier: APHP231767
• Study Type: observational
• Target: 1,000
• Locations: 0 countries
• Sites: N/A

Brief Summary

Intellectual disability (ID) is characterized by having an intelligence quotient (IQ) below 70 and substantial limitations in adaptive functioning across different domains, with the condition manifesting before the age of 18. Historically, it was noted that 25% of ID cases were attributed to acquired causes such as perinatal anoxia or infections, another 25% were linked to genetic factors, and the remaining 50% had an 'undetermined' cause. However, with advancements in genetic diagnosis, the proportion of cases with unknown causes is gradually diminishing, giving way to a greater understanding of genetic etiologies. The rarity of each of these causes of ID and the lack of specificity of most of the syndromes mean that it is often difficult to make an aetiological diagnosis. The objective of this study is to describe the nature and frequency of genetic abnomalties identified in adult patients with intellectual disability. This is a descriptive, retrospective and prospective study that aim to include 1000 patients across 10 centres aged over 20 years old on consultation between 2016 to 2025 who have been informed (where applicable, the guardian), who have not oppose to participate and who meet the inclusion and non-inclusion criteria. Each centre will include and increment a patient identification number for pseudonymisation of reports. A name correspondence table will be maintained by each center to establish a link between the research identifier and the participant's identity. Each table will be stored on each centre's secure server. The anonymized reports will be transmitted to the coordinating team through the secure Dispose platform, which will transfer all the participants' data to a REDCap APHP database. Descriptive statistic will be performed to count the number of patients with the same genetic syndrome. The age of onset of comorbidities and the proportion of each complication by syndromes will be calculated for all patient, including the means and median.

Conditions

Intellectual Disabilities

Keywords

Phenotypes; intellectual disabilities; genetic abnormalities

Outcome Measures

Primary Outcomes (1)

• List and frequency of genetic anomalies identified in adults with an intellectual disability

  Through study time period (24 months)

Secondary Outcomes (3)

• Describe the clinical phenotype in adulthood corresponding to the genetic anomalies identified, with particular attention to adults over 45 years of age

  Through study time period (24 months)

• Describe the co-morbidities and complications of genetic syndromes over time

  Through study time period (24 months)

• Evaluate the frequency of genetic diagnosis in adults with ID

  Through study time period (24 months)

Eligibility Criteria

• Age: 21 Years+
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)
• Sampling Method: Non-Probability Sample

Study Population

Patient over 20 years of age with a proven intellectual disability, seen in consultation between 2016 and 2025

You may qualify if:

• Patient over 20 years of age with a proven intellectual disability,
• Patient seen in consultation between 2016 and 2025
• No objection from the patient or, where applicable, the guardian

You may not qualify if:

• Medical file not available
• Opposition from the patient or, where applicable, the guardian.

Sponsors & Collaborators

• Assistance Publique - Hôpitaux de Paris: lead

MeSH Terms

Conditions

Intellectual Disability

Condition Hierarchy (Ancestors)

Neurobehavioral Manifestations; Neurologic Manifestations; Nervous System Diseases; Signs and Symptoms; Pathological Conditions, Signs and Symptoms; Neurodevelopmental Disorders; Mental Disorders

Central Study Contacts

Daphné LEHALLE

CONTACT

01 42 16 12 56; daphne.lehalle@aphp.fr

Study Design

• Study Type: observational
• Observational Model: COHORT
• Time Perspective: PROSPECTIVE
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: September 9, 2024
• First Posted: October 8, 2024
• Study Start (Estimated): November 1, 2026
• Primary Completion (Estimated): November 1, 2026
• Study Completion (Estimated): November 1, 2028
• Last Updated: July 3, 2025

Record last verified: 2024-09

Data Sharing

• IPD Sharing: Will share
• Shared Documents: STUDY PROTOCOL, SAP, ICF
• Time Frame: Beginning 3 months and ending 3 years following article publication. Requests out of these time frame can also be submitted to the sponsor
• Access Criteria: Researchers who provide a methodologically sound proposal.