RESUMO
STUDY DESIGN: An open-label, multicentre study was conducted to evaluate the antihypertensive efficacy of a 4-week course of losartan 50 mg plus hydrochlorothiazide 12.5 mg in Asian patients with essential hypertension whose blood pressure had previously been treated with but not controlled by valsartan 80 mg. METHODS: A total of 237 eligible patients with mean trough sitting diastolic blood pressure (SiDBP) 95-115 mmHg and a mean trough sitting systolic blood pressure (SiSBP) < 190 mmHg entered the baseline period of treatment with valsartan 80 mg/day for 4 weeks. Those (n = 165) whose SiDBP remained > 90 mmHg and who were not excluded for other reasons were then switched to a single-tablet formulation of losartan 50 mg/hydrochlorothiazide 12.5 mg combination once daily for a further 4 weeks. RESULTS: Mean SiDBP (study primary endpoint) at the end of combination therapy was reduced to 86.9 mmHg from 95.2 mmHg. SiSBP (study secondary endpoint) was reduced to 132.6 mmHg from 140.7 mmHg. Mean reductions after switching from valsartan 80 mg to losartan 50 mg/hydrochlorothiazide 12.5 mg were thus 8.3 and 8.1 mmHg for SiDBP and SiSBP, respectively (p < or = 0.001 for both outcomes). The goal of SiDBP < or = 90 mmHg was attained in 72% of the patients previously not controlled to the same level by valsartan 80 mg/day. Combination therapy with losartan 50 mg/hydrochlorothiazide 12.5 mg was generally well tolerated. Mean compliance with the losartan 50 mg/hydrochlorothiazide 12.5 mg combination was > 99%. CONCLUSION: These results demonstrate that in Asian patients who do not reach the goal of mean trough SiDBP < or = 90 mmHg with valsartan monotherapy at 80 mg once-daily, switching to a single-tablet combination of losartan 50 mg/hydrochlorothiazide 12.5 mg once-daily is well tolerated, provides effective control of blood pressure and is an excellent choice to achieve blood pressure reduction goals.
Assuntos
Bloqueadores do Receptor Tipo 1 de Angiotensina II/uso terapêutico , Anti-Hipertensivos/uso terapêutico , Pressão Sanguínea/efeitos dos fármacos , Hipertensão/tratamento farmacológico , Losartan/uso terapêutico , Inibidores de Simportadores de Cloreto de Sódio/uso terapêutico , Adulto , Idoso , Bloqueadores do Receptor Tipo 1 de Angiotensina II/administração & dosagem , Anti-Hipertensivos/administração & dosagem , Povo Asiático , Combinação de Medicamentos , Feminino , Humanos , Losartan/administração & dosagem , Masculino , Pessoa de Meia-Idade , Inibidores de Simportadores de Cloreto de Sódio/administração & dosagem , Tetrazóis/uso terapêutico , Valina/análogos & derivados , Valina/uso terapêutico , ValsartanaRESUMO
The long-term roles of dietary sodium and potassium on the renal end-organ damage of hypertension were investigated in Wistar-Kyoto (WKY) and in spontaneously hypertensive (SHR) rats. Eight rats from each strain were maintained since 1 month of age on one of four dietary combinations of either low (0.4%) or high (6.0%) NaCl and low (0.51%) or high (7.6%) KCl providing sodium/potassium molar ratios of 1:1, 1:15, 15:1, and 15:15, respectively. Urinary sodium/potassium excretion ratios confirmed the proportion of salts consumed. Systolic blood pressures (SBP) were similar at 5 months of age and at the completion of the study at 9.5 months; SBP was significantly higher in SHR than in WKY rats and was not attenuated by dietary potassium supplementation of a magnitude that raised plasma potassium concentrations. Albumin excretion rate (AER) was also higher in SHR than in WKY rats (P less than 0.0001). In SHR, AER rose further with high sodium intake (P less than 0.035) but, contrary to SBP, was ameliorated by an equimolar addition of potassium (P less than 0.01). Morphologic lesions were generally absent in WKY rats and were more common in SHR as a group (P less than 0.001). In all four SHR groups, the graded histopathologic injury correlated well with measured AER but a major improvement in hypertensive renal lesions occurred largely in the KCl-supplemented, salt-loaded SHR group. These results show a disassociation between the effects of dietary monovalent cations on the level of SBP and their effect on renal injury. Sodium aggravates renal injury and potassium protects against this renal effect of sodium independent of SBP effect.(ABSTRACT TRUNCATED AT 250 WORDS)