Polycythemia

The purpose of this study is to evaluate the effect of the (angiotensin-converting enzyme) ACE inhibitor lisinopril on hemoglobin, hematocrit, and erythropoietin levels in patients with secondary polycythemia due to high-oxygen-affinity hemoglobin variants, oxygen-sensing pathway mutations, or other unexplained and potentially irreversible forms of erythrocytosis. This study aims to determine whether ACE inhibition can effectively reduce excessive erythrocytosis by modulating erythropoietin production.

Our study is designed to characterize the clinical picture and genetic pattern of Polycythemia and Thrombocytosis. The purpose of this project is to find a gene and its mutation that causes these disorders. When this is accomplished, new therapies to control and eventually cure the disorder can be designed.

The goal of this NIH-sponsored study is to characterize three biomarkers derived from 129Xe gas exchange MRI and to understand how they change in response to interventions.

Polycythemia vera (PV) is a rare haematological disorder characterized by an excessive production of red blood cells, associated with the somatic JAK2 V617F mutation. Clinical manifestations are varied and often include exercise intolerance but the underlying mechanisms remain poorly understood. Physical activity is recommended in the management of chronic diseases, but it must be tailored to the physiological profile of the patient. A cardiopulmonary exercise test (CPET) is essential to ensure safety, detect possible contraindications, and assess maximal oxygen uptake (VO₂max), a key indicator of aerobic performance. This prospective, experimental, non-randomized study will include patients with PV followed at Lyon Sud University Hospital and for which a CPET is scheduled in their routine clinical follow-up. The primary objective is to compare VO₂max between two groups of patients: moderate (\<10%) versus marked (≥10%) extent of blood viscosity increase after the completion of the CPET. The main hypothesis is that a significant increase in blood viscosity during exercise (≥10%) is a major limiting factor in oxygen transport and leads to a reduced VO₂max, reflecting impaired exercise tolerance. Secondary analyses will focus on hemorheological parameters, tissue oxygenation, and cardiorespiratory and metabolic responses. The study aims to better understand the biological and physiological determinants of exercise intolerance in this population.

Objectives: To compare the response of polycythemia in terms of hematocrit decrease in patients treated with positive airway pressure (CPAP) versus patients not treated with CPAP. Methodology: Randomized, parallel-group, nonblinded, controlled clinical trial. Patients diagnosed with OSA in a respiratory polygraphy (RP) and who meet all the inclusion criteria and none of the exclusion criteria will undergo sleepiness and quality of life questionnaires, anthropometric measurements and blood tests and will be randomized to a CPAP treatment group or control group, maintaining this treatment for 12 months. A visit will be made at 12 weeks ,24 weeks and 52 weeks to check compliance with CPAP in the treatment group and to carry out questionnaires on physical activity and quality of life, anthropometric measurements, blood tests including hemoglobin and hematocrit as well as parameters related to coagulation and platelet function and changes in medication as well as adverse effects. Efficacy variables: blood count, hemoglobin, haematocrit, erythropoietin, mean corpuscular volume (MCV), mean corpuscular haemoglobin (MCH), mean corpuscular haemoglobin concentration (MCHC), mean platelet volume (MPV), platelets, coagulation, erythrocyte range of distribution (ADE), glucose, creatinine, glomerular filtration rate, aspartate aminotransferase (AST), alanine aminotransferase (ALT), gamma glutamyltransferase (GGT), Total bilirubin, hypoxic burden, Epworth score, EuroQol- 5D questionnaire.

The EValuation of ERythrocytosis pRospEctive cohort STudy (EVEREST) is a prospective study designed to shed light on these key questions in the diagnosis, management, and clinical outcomes in patients with elevated hemoglobin (erythrocytosis). This longitudinal, prospective study will generate high quality data that can help inform the optimal approach to diagnosis and management in this patient population.

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.