Effect of Phlebotomy on Heartrate in Polycythemia Patients

Study Overview
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Brief Summary
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Single-centre, observational within-subject design: patients that undergo phlebotomies regularly for polycythemia will be measured continuously by wearables one week before until one week after a phlebotomy, for three phlebotomies.

Detailed Description
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Rationale: Little is known about the effect of a hemoglobin-shift on patients, anaemic, non-anaemic or even polycythaemic. It has been established that severe anaemia has deteriorating effects on the patient, which can be (partially) reversed by treatments like transfusion, erythropoietin stimulating agents or iron/vitamin supplements, depending of the etiology of the anaemia. However, the optimal haemoglobin target and threshold for such treatments has yet to be determined. It is therefore necessary to evaluate what the exact effect of various haemoglobin levels, and a shift therein, is on the physiology of patients. Only then can the benefits be weighed properly against the risks for individual patients when considering treatment for anaemia, safety of blood donation, or expected effect of phlebotomy for polycythaemia. Primary Objective: - Compare the per individual and per group effects of a reduction in Hb mass on physical functional outcomes (heart rate; activity parameters; QoL) in patients with polycythaemia. Secondary Objectives: - Compare the primary outcomes to data from the REMOTE-2 and FAINT-study (similar measurements in transfusion dependent patients and whole blood donors) Study design: Within-subject design. Patients will be remotely monitored one week before phlebotomy until one week after. Study population: Adult patients with a polycythaemia requiring phlebotomies on a regular basis. Main study parameters: heart rate, blood pressure, activity parameters and quality of life.

Official Title
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Phlebotomy in Blood Donors and Polycythemia Vera Patients- The Effect on Physiology: An Orienting Case-Cross Over Study

Conditions
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Polycythemia

Intervention / Treatment
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* Procedure: phlebotomy


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patients with polycythaemia, requiring phlebotomy on a regular basis (at least every 4 months) Subjects aged ≥18 years In possession of a smartphone Life expectancy ≥ 3 months Exclusion Criteria: Poor performance/functional status (Eastern Cooperative Oncology Group system ECOG ≥3) Participants with known arrhythmias or other significant cardiological conductivity disorders (Paroxysmal atrial fibrillation is allowed) Hospitalized subjects Subjects with a pacemaker. Subjects with a secondary polyglobulia due to eg smoking or other pulmonary issues. Scheduled oncological treatments or surgery during the study period.

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Arms and Interventions

| Intervention/Treatment |
| --- |
|Procedure: phlebotomy|500ml of blood phlebotomized per standard of care to reduce symptoms from polycythemia|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Mean heart rate as measured by the withings BPM and withings Steel HR biodevices | the Withings BPM will give point measurements while the withings Steel HR gives continuous heart rate measurements. We will compare before the phlebotomy to after phlebotomy and >48hrs after phlebotomy, within-subjects. | one week before until one week after phlebotomy; for three phlebotomies | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Systolic and diastolic blood pressure as measured by the withings BPM connect. | BP (systolic/diastolic) measured by Withings BPM connect | Daily basis from one week before until one week after phlebotomy; three phlebotomies | 
| Number of steps per 24hrs as measured by the withings steel HR | Steps as a measure for activity as measured by the withings steel HR | one week before until one week after phlebotomy; for three phlebotomies | 
| Quality of life as measured by the EuroQol-5D questionnaire (EQ5D) | QoL as measured by the castor-based EQ5D. The EQ5D gives two scores: the utility score (range: -.329 to 1, higher is better, lower than 0 is considered worse than death) and an VAS (visual analogue scale) score (range 0 to 100, higher is better) | Daily basis from one week before until one week after phlebotomy; three phlebotomies |