Effects of losartan on the renin-angiotensin-aldosterone system and erythrocytosis in patients with chronic obstructive pulmonary disease and systemic hypertension
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Dosyalar
Tarih
2001
Dergi Başlığı
Dergi ISSN
Cilt Başlığı
Yayıncı
Adis Int Ltd
Erişim Hakkı
info:eu-repo/semantics/closedAccess
Özet
Objective: To evaluate the effects of losartan on blood pressure, erythrocytosis and the renin-angiotensin-aldosterone system (RAS) in patients with erythrocytosis and hypertensive chronic obstructive pulmonary disease (COPD). Design: Prospective, nonrandomised, two-period study. Patients and Participants: 24 patients were recruited, of whom 20 (17 men) completed the trial. The mean age was 55 +/- 8 years (range 40 to 65 years). Erythrocytosis was defined as a persistent elevation of the haematocrit to greater than or equal to 47% in females and greater than or equal to 50% in males. Patients were less than or equal to 65 years of age and hypertensive according to the WHO criteria. Patients who had hepatic and/or renal dysfunction, acute exacerbation of primary disease, were taking systemic corticosteroids, had any other systemic disease, or showed intolerance during the washout period were excluded. Methods: An initial 2-month period on, a standard regimen with nasal oxygen (2 L/min, 18 h/day) and bronchodilators (inhaled salbutamol, oral theophylline, inhaled ipratropium bromide) was followed by a second 2-month period during which losartan was administered as an antihypertensive agent in addition to standard therapy. Routine biochemical and haematological monitoring was carried out. Systolic and diastolic blood pressures (SBP and DBP respectively) were measured. ECG and arterial blood gas analyses were also performed for all patients at the beginning of the study, and all of these clinical and laboratory investigations were performed at 15-day intervals during the study. Plasma renin activity and serum aldosterone and erythropoietin levels were measured both at the beginning and at the end of each 2-month period. Results: No statistically significant changes were found in the measured parameters at the end of the 2-month standard treatment period. Fatigue and dizziness were reported by four of the patients during the first week of losartan treatment. Both SEP and DBP decreased by 10mm Hg with losartan treatment (p = 0.0003 and 0.0002, respectively). Haematocrit decreased from 53 +/- 3% to 48 +/- 4% (p = 0.0001). The mean arterial blood gas tension of CO2 (pCO(2)) was 54 +/- 11mm Hg and decreased to 48 +/- 4mm Hg (p = 0.01). Losartan treatment decreased serum aldosterone to 259 +/- 148 ng/dl from a mean baseline value of 156 +/- 140 ng/dl (p = 0.03). There were no statistically significant changes in pO(2) serum erythropoietin or plasma renin activity. Conclusion: Losartan controls blood pressure and reduces erythrocytosis in patients with hypertensive COPD, and is well tolerated. Although the mechanism of the effect of losartan on erythrocytosis requires further investigation, we propose that the RAS, in particular angiotensin II, has effects on the haemopoietic system and that blocking these effects decreases the haematocrit.
Açıklama
Anahtar Kelimeler
Renin-Angiotensin-Aldosterone, Losartan, System and Erythrocytosis, Chronic Obstructive Pulmonary, Disease and Systemic Hypertension
Kaynak
Clinical Drug Investigation
WoS Q Değeri
Q3
Scopus Q Değeri
Q2
Cilt
21
Sayı
5
