Dementia Phenotypes in Primary Care, Hospital, and National Mortality Registries

Dementia Clinical Trial

Official title:

Dementia Phenotypes in Primary Care, Hospital, and National Mortality Registries: a Cohort Study in Linked Electronic Health Records

Clinical Trial Details — Status: Active, not recruiting

Administrative data

• NCT number: NCT02549872
• Other study ID #: 15_138
• Status: Active, not recruiting
• Phase: N/A
• First received: September 3, 2015
• Last updated: September 11, 2015
• Start date: September 2015
• Est. completion date: December 2015

Study information

• Verified date: September 2015
• Source: University College, London
• Contact: n/a
• Is FDA regulated: No
• Health authority: United Kingdom: Medicines and Healthcare Products Regulatory Agency
• Study type: Observational

Clinical Trial Summary

Most patients with dementia in the UK use their local hospitals and general (family) practices throughout their illness. Linked electronic health records from primary care, hospital and death certificates records therefore provide useful information about the diagnosis and prognosis of patients who develop dementia.

In this study we will assess the validity of dementia diagnoses in linked primary care, hospital and death records, by examining the timing of important health transitions in patients with recorded dementia, and we will estimate the lifetime risk of recorded dementia in different age and sex groups

Description:

Dementia is a clinical syndrome with insidious onset that is difficult to diagnose in its earliest stages. Presentation to healthcare depends not only upon the rates of disease progression, but also on social support, recognition by clinicians, and patients' and carers' fear of diagnosis. Maintaining complete follow up in cohorts of patient with dementia is difficult, because patients with dementia are frequently lost to follow up.

Most patients with dementia in the UK use their local hospitals and general (family) practices throughout their illness. Linked electronic health records from primary care, hospital and death certificates records should therefore provide useful information about the diagnosis and prognosis of patients who develop dementia with minimal loss to follow-up rates and improved completeness of diagnosis.

Demonstrating that patients with recorded dementia have an earlier onset of typical symptoms, functional impairment and death than patients in the general population would support the veracity of diagnosed dementia recorded in electronic health records and its use as an outcome or exposure in cohort studies and for evaluating policy. Previous studies have found that dementia is poorly recorded in routine clinical practice in comparison to face-to-face studies, although this varies by setting and region. However, ascertainment may be improved by examining linked, longitudinal resources. Comparing the lifetime risk of dementia calculated from linked electronic health records with lifetime risks from other sources will also be a useful information to support the use of linked electronic health records in dementia research.

Electronic health records contain information on important health transitions in patients with dementia: from the earliest stage of the illness (depression, anxiety, memory complaints); the development of cognitive impairment that manifest as loss of capacity or missed appointments; and significant functional impairment, with admission to nursing homes or hospital admission. In this study, we will assess the validity of dementia diagnoses in linked primary care, hospital and death records, by examining the timing of important health transitions in patients with recorded dementia, and estimate the lifetime risk of recorded dementia in different age and sex groups.

Recruitment information / eligibility

• Status: Active, not recruiting
• Enrollment: 51000
• Est. completion date: December 2015
• Est. primary completion date: October 2015
• Accepts healthy volunteers: Accepts Healthy Volunteers
• Gender: Both
• Age group: 18 Years and older

Eligibility

Inclusion Criteria:

• Patients aged 18 years and over

• Registered with a participating general practice during the study period

• Minimum one year of records prior to study entry meeting CPRD data quality criteria

• Followed on or after 1 January 1997

Exclusion Criteria:

• Patients without recorded gender

• Less than 1 year of follow-up between study entry and date of administrative censoring

Study Design

Observational Model: Cohort, Time Perspective: Retrospective

Related Conditions & MeSH terms

• Dementia

Intervention

Other:
• This is not an intervention study
This study is based on the retrospective analysis of linked electronic health records.

Locations

Country	Name	City	State
United Kingdom	London Farr Institute of Health Informatics	London

Sponsors (4)

Lead Sponsor	Collaborator
University College, London	Medical Research Council, University of Edinburgh, University of Leeds

Country where clinical trial is conducted

United Kingdom, 

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	Proportion of patients with dementia diagnosis (any type) in primary care that also are recorded in secondary care		10 years	No
Primary	Factors associated with dementia diagnosis (any type) recording in mortality data only	These will be estimated from multivariable logistic regression models	10 years	No
Primary	Symptoms associated with subsequent diagnosis of dementia	These will be estimated from multivariable logistic regression models	10 years	No
Primary	Lifetime risk of dementia (any type)		10 years	No
Primary	Lifetime risk of mortality associated with dementia (any time)		10 years	No
Primary	Factors associated with dementia diagnosis (any type) recording in secondary care only	These will be estimated from multivariable logistic regression models	10 years	No
Primary	Factors associated with dementia diagnosis (any type) recording in primary care only	These will be estimated from multivariable logistic regression models	10 years	No
Primary	Proportion of patients with dementia diagnosis (any type) in primary care that also are recorded in mortality data		10 years	No
Primary	Proportion of patients with dementia diagnosis (any type) in secondary care that also are recorded in mortality data		10 years	No
Secondary	Proportion of patients with Alzheimer's disease in primary care that are also diagnosed in secondary care		10 years	No
Secondary	Proportion of patients with vascular dementia in primary care that are also diagnosed in secondary care		10 years	No
Secondary	Lifetime risk of Alzheimer's disease		10 years	No
Secondary	Lifetime risk of vascular dementia		10 years	No
Secondary	Lifetime risk of mortality associated with Alzheimer's disease		10 years	No
Secondary	Proportion of patients with Alzheimer's disease in primary care that are also diagnosed in mortality data		10 years	No
Secondary	Proportion of patients with Alzheimer's disease in secondary care that are also recorded in mortality data		10 years	No
Secondary	Proportion of patients with vascular dementia in primary care that are also recorded in secondary care		10 years	No
Secondary	Proportion of patients with vascular dementia in secondary care that are also recorded in mortality data		10 years	No