PAD Registry and Fitbit Sub-Study Program
Condition: Peripheral Artery Disease
MeSH terms: Peripheral Arterial Disease
Study type: Observational [Patient Registry]

Summary: 
      The genetic contribution and influence on the progression of peripheral artery disease (PAD)
      and possible cardiovascular events remains relatively unknown. As a result, the investigators
      are proposing for the creation of a registry of patients in the University of Pennsylvania
      Health System who are known to have PAD. The patients in this registry will be systematically
      monitored by conducting lower extremity ultrasound exams, ankle-brachial index (ABI)
      measurements, and six minute walk tests which have strong value in the positive diagnoses of
      PAD. These exams, combined with follow-up quality of life questionnaires, would allow for
      thorough monitoring of new diagnoses, symptoms, or serious adverse events. Blood will also be
      drawn looking for genetic biomarkers associated with this disease, which will provide further
      knowledge on the advancement and potential cardiovascular events associated with this
      disease. This blood will also be analyzed for components that will provide the investigators
      with knowledge of the patients overall blood vessel health. Micro RNA will also be evaluated
      to try to test if proteins and RNA in the blood can be used as predictors for future strokes
      or heart attacks. These exams will be repeated once annually over a duration of 10 years,
      with patients having hemodynamic monitoring as well as quality-of-life and cardiovascular
      events recorded at each visit. The data obtained from this registry will be compared to a
      created genetic profile looking for any genetic contribution to these new developments.
      Furthermore, this knowledge should offer impetus for physicians to target patients with these
      risk factors for the identification of potential adjustments to care.
    

Detailed description: 
      500 subjects will be recruited from the general Philadelphia community and from the
      University of Pennsylvania Healthcare System. This population will be carefully characterized
      with assessment for cardiovascular risk factors to include smoking, diabetes mellitus,
      hypertension, and previous surgery or vascular interventions. Those patients with the
      presence of diabetes, hypertension, and hypercholesterolemia will be considered positive if
      they are being prescribed drugs for each respective condition. Physician's clinics will be
      screened for patients who meet the necessary inclusion criteria. These physicians will then
      be contacted for permission to speak with the patient. Upon approval, a coordinator will
      contact the patient regarding the study and to gauge interest. If interested, the coordinator
      will go through a screening form with the patient, as well as schedule a baseline visit.
      Subjects will also be recruited from Upenn research database comprised of subjects who have
      participated in previous research studies and who have asked to be contacted for future
      studies, such as CVI BioBank, Genetics of Cardiovascular and Metabolic Phenotypes (IRB
      #808346). Potential subjects will also be recruited via Penn Data Store. Patients who cannot
      be contacted directly will be contacted through the mail.

      For their baseline visit, patients will be asked to read and sign the consent form, as well
      as approached for participation in the CVI BioBank, Genetics of Cardiovascular and Metabolic
      Phenotypes (IRB# 808346). Additionally, patients will be given the option of participating in
      the activity monitoring sub-study. Patients will then asked to undergo an ABI measurement
      using standardized methods - brachial and ankle systolic pressures will be measured with
      appropriately sized cuffs attached to sphygmomanometers. Return of flow will be determined
      using a continuous wave Doppler. In addition, patients will undergo a lower extremity duplex
      ultrasound evaluation of their arterial system, with plaque being used as a measure of
      disease progression. The evaluation will be done in coordination with the Inter-societal
      Commission for Accreditation of Vascular Laboratory Guidelines. In each follow-up exam, PAD
      progression will be defined as either a new stenosis or progression of a baseline stenosis to
      an occlusion. Furthermore, patients will undergo a 6-MWD test, with the primary unit of
      analysis being the total distance walked (in meters) regardless of whether the subjects
      stopped or not during the conduct of the test. Patients will also have 10 mLs of blood drawn,
      which will be evaluated for any genetic and vascular biomarkers that may have contributed to
      the disease (see Section 3.0 for Analysis and Evaluation). Micro RNA will also be evaluated
      for any predictors of future strokes or heart attacks. Study visits will be completed once
      annually over duration of 10 years, with questionnaires being repeated every 6 months via
      telephone. These questionnaires, the Walking Impairment Questionnaire (WIQ) and RAND-Item
      short Form Survey, will be completed and will ask the patients about any interval changes in
      medical history, any severe adverse events that may have occurred, and their overall quality
      of life.

      Patients enrolled in the optional activity monitoring sub study will be randomized to one of
      two groups: intervention group or control group. Intervention group participants will receive
      an activity monitor device (Fitbit http://www.fitbit.com/) and instructed on its use.
      Additionally, coordinators will monitor the intervention groups usage of the device and make
      routine recommendations on their activity level using the Way To Health platform. Way to
      Health is an integrated research platform that uses online tools, wireless technologies, and
      other applications to allow investigators to test ways of improving health behaviors and
      helping people keep on track to better health. Patients in the intervention group will also
      receive financial incentives for wearing the Fitbit and also be entered into a lottery if
      they are reaching their goals. Patient's will be increased by the Way To Health program
      according to the algorithm described below:

        -  <5000 steps: 50% increase on goal

        -  5,001 - 7,500 steps: 40% increase on goal

        -  7,501 - 10,000 steps: 30% increase on goal ->10,000 steps: 20% increase on goal

      Participants in the control group will receive an activity monitoring device that they will
      not be able to engage with but instructed to wear for monitoring purposes once a week every
      month. Each subject will perform the same procedures used on patients not enrolled in the
      sub-study. However, patients will be asked to return to our office for a 3 month follow-up
      visit for a repeat 6 minute walk test and Walking Impairment Questionairre (WIQ). The data
      recorded on the activity monitor device will be uploaded by the subjects for view via sync
      through proprietary software on a smartphone, tablet, or computer. The data will be password
      protected and will allow access to the investigator and the subjects randomized to the
      intervention group to have access.
    

Intervention name(s): Fitbit Sub-Study
Intervention type(s): Device
Observational model: Cohort
Time perspective: Prospective
Sampling method: Probability Sample
Study population: 
        Peripheral Artery Disease is a disease that is highly prevalent within the United States,
        affecting close to 8-12 million individuals. These individuals' qualities of life are
        likely impaired due to limited walking ability, shortness of breath, and claudication. In
        addition, it is well known that risk factors such as smoking, diabetes mellitus,
        hypertension, and dyslipidemia can play a role in the onset of this disease