Atrial Fibrillation Research In CATalonia
Condition: Arrhythmia Atrial; Atrial Fibrillation; Hypertension; Diabetes Mellitus
MeSH terms: Atrial Fibrillation
Study type: Observational [Patient Registry]

Summary: 
      The AFRICAT study is a prospective, multicenter, population-based study, which aims to create
      and apply a sequential screening program for atrial fibrillation (AF) in a high-risk
      population by integrating clinical, electrocardiographic and biological information. The
      study will be divided into three different phases of generation, validation and application
      of a screening program.

      In Phase I, from 8,000 individuals aged 65-75 with hypertension and diabetes identified from
      primary center registries, 100 will be randomly selected . In these patients, the
      investigators will complete clinical assessment, testing of different pulse-handheld ECG
      devices (MyDiagnostik, AliveCor and WatchBP) for AF screening, discovery of blood biomarkers
      for AF (by aptamer technology and RNA expression), and validation of biological candidates
      from the literature and previous results. All patients will receive Holter monitoring with a
      wearable device (NuuboTM). In parallel, a predictive risk model for AF will be developed from
      historical records from the areas in which the study will be carried out.

      This Phase I will be followed by a Phase II-validation phase of 400 patients, selected by the
      predictive model previously mentioned, belonging to the top risk quartile. In these patients,
      the best biomarkers and devices from phase I will be validated, and patients will be again
      monitored with the wearable Holter device.

      With the results from this validation analysis, a screening program (Phase III) based in the
      combination of clinical predictors, devices to detect AF (handheld-ECG or pulse wave
      detectors), blood biomarkers determination and long-term monitoring with wearable Holter.
      This program will be applied over the whole population targeted by the AFRICAT study, which
      corresponds to 8,000 patients from 65 to 75 years old, whit hypertension and diabetes
      mellitus as comorbidities.
    

Detailed description: 
      The study has been approved by the Ethics Committee of Research Institute IDIAP Jordi Gol
      (P15/047/2015) and by Hospital Universitari Vall d'Hebron Clinical Research Ethics Committee
      (PR(AG)133-2015). The study will be conducted in compliance with the Declaration of Helsinki.
      Registry information was collected from the government-run healthcare provider responsible
      for all inpatient care in Catalonia. All participants will receive written information and
      thereafter sign informed consent before inclusion, will be selected among the electronic
      registers from two different health areas in Catalonia, and will be identified by their
      10-digit personal identification number assigned to all citizens in Catalonia.

      These patients will be given an appointment in their primary care centre and will receive a
      comprehensive assessment consisting of:

        -  Clinical characteristics: demographic factors (age, gender, habits); vascular risk
           factors (hypertension, diabetes, dyslipidemia), medications, comorbidities (especially
           those related to AF such as coronary disease, heart failure), vital signs (blood
           pressure, glycaemia, weight and height).

        -  Electrocardiographic assessment: three different devices will be tested on each
           participant (MyDiasnostik, AliveCor and WatchBP). A conventional ECG will be performed
           to be compared with the results from these devices.

        -  Blood sample collection: a blood sample of 32 cc divided into two serum tubes (8.5 cc),
           two plasma EDTA tubes (6 cc) and one TempusTM RNA tube (3 cc). Samples will be processed
           and stored at -20 ºC at the recruiting centre until shipment to Neurovascular Research
           Laboratory, where the sample bank will be set up.

        -  Holter ECG monitoring: a Nuubo Holter will be given to each patient to be carried for
           four weeks. Electrocardiographic devices will be read blindly. The device records,
           anonymized and encrypted, will be sent for blinded reading to the Rhythm Disorders Unit
           from Hospital Virgen del Rocio in Seville.
    

Observational model: Ecologic or Community
Time perspective: Prospective
Sampling method: Probability Sample
Study population: 
        All people included were managed by the Public Health System. Therefore 5,000 participants
        aged 65-75 with active diagnoses of hypertension (I10) and diabetes (E10.9 E11.9) will be
        selected from the electronic health record of Primary Care. Given that the registered
        prevalence of Atrial Fibrillation in this population is was 7.3%, the investigators
        estimated that around 2.8% will be newly diagnosed with AF at the first study visit.
        Therefore, the investigators estimate that the number of patients in this population who
        have undiagnosed AF might be from 140 to 210 patients, taking into account that AF
        detection should be improved in the study given the long-term monitoring.
      
Biospecimen description: 
      A blood sample of 32 cc divided into two serum tubes (8.5 cc), two plasma EDTA tubes (6 cc)
      and one TempusTM RNA tube (3 cc). Samples will be processed and stored at -20 ºC at the
      recruiting center until shipment to Neurovascular Research Laboratory, where the sample bank
      will be set up.
    
Keywords: Atrial Fibrillation; Electrocardiography; Biological Markers; Risk Assessment