Beneficial Effect of Switching from a Combination of Angiotensin II Receptor Blockers other than Losartan and Thiazides to a Fixed Dose of Losartan/Hydrochlorothiazide on Uric Acid Metabolism in Hypertensive Patients

Survey on uric acid in Chinese subjects with essential hypertension (SUCCESS): a nationwide cross-sectional study

Background

Hyperuricemia (HUA) is associated with hypertension and increased cardiovascular risk. Current data regarding the prevalence of HUA in Chinese hypertensive patients are lacking. Our study aims to explore the prevalence and determinants of HUA in Chinese hypertensive adults.

Methods

Treatment-naive hypertensive adults or those taking single antihypertensive agent were included in a nationwide cross-sectional study. Basic demographics, antihypertensive medications, serum uric acid (UA), and other parameters were documented.

Results

The overall prevalence rate of HUA was 38.7% among 33,785 valid cases, 35.1% for males (UA >420 µmol/L), and 45.2% for females (UA >360 µmol/L). A multiple logistic regression analysis, adjusted for demographic and clinical factors (model 1), revealed that female sex [odds ratio (OR), 95% CI, 1.43, 1.36–1.51], age of ≥65 years (1.12, 1.05–1.19), low evaluated glomerular filtration rate [eGFR; 2.06, 1.91–2.23, the lowest [Q1] vs. the highest quartile (Q4)], unmarried (1.58, 1.10–2.27), Western China residency (3.21, 3.33–3.91), longer hypertension duration (1.97, 1.78–2.12, Q4 vs. Q1) and aspirin use (1.21, 1.14–1.29) were associated with HUA. In a multiple logistic regression analysis adjusted for clinical and metabolic parameters (model 2), female sex (OR, 95% CI, 1.34, 1.27–1.41), age of ≥65 years (1.09, 1.03–1.16), low eGFR (2.35, 2.19–2.52, Q1 vs. Q4), new–onset hypertension (2.01, 1.73–2.33), higher quartile of fasting blood glucose (FBG), triglyceride (TG), low density lipoprotein cholesterol (LDL-C) levels, and body mass index (BMI) were associated with higher risk of HUA (1.89, 1.76–2.03; 2.15, 1.99–2.31; 2.86, 2.67–3.06; 1.27, 1.27–1.36, respectively, Q4 vs. Q1). Losartan, valsartan, and nifedipine were associated with lower risk of HUA (OR, 95% CI, 0.77, 0.67–0.88, 0.68, 0.60–0.77; 0.87, 0.77–0.99, 0.79, 0.70–0.89 and 0.80, 0.70–0.91, 0.82, 0.72–0.92), respectively, in models 1 and 2.

Conclusions

The prevalence rate of HUA in Chinese hypertensive patients was 38.7%. Female sex, aging (≥65 years), and low eGFR were independent predictors of HUA. HUA was lower among the patients who were taking losartan, valsartan, and nifedipine. Western region residents, new-onset hypertension, longer hypertension duration, aspirin use, higher FBG, TG, LDL-C levels and BMI were potential risk factors for HUA.

URAT1 gene polymorphisms influence uricosuric action of losartan in hypertensive patients with hyperuricemia

Aims: To explore the effect of urate transporter 1 (URAT1) polymorphisms on the hypertensive patients with hyperuricemia and the uricosuric action of losartan therapy among hypertensive patients with hyperuricemia. Methods: 101 hypertensive patients with hyperuricemia were detected the genotypes of URAT1 rs1529909 and rs3825016 and undergo a 2-weeks following losartan treatment. Before and after treatment, serum uric acid (SUA) and other clinical data were compared between different genotypes of URAT1 patients. Results: The frequency of rs3825016 (C/T) CT genotype was significant higher in the hypertensive patients with hyperuricemia than that in the healthy controls (32.7 vs 18.8%; p = 0.02). After lorsatan treatment, the patients with the rs3825016 (C/T) or rs1529909 (T/C) mutant genotypes had lower decreased value (DV) of SUA compared with the patients who are wild-type of the variant (p = 0.001 and p < 0.001, respectively). Combined the two variants together, the DV of SUA in two variants both wild-type patients higher than that in the two variants mutant patients (p < 0.0001). Conclusion: These results suggest that URAT1 rs3825016 and rs1529909 polymorphisms influence the uricosuric action of losartan.

Original submitted 20 August 2014; Revision submitted 15 April 2015

Effect of losartan on serum uric acid in hypertension treated with a diuretic: the COMFORT study

It has been shown that losartan, an angiotensin II receptor blocker (ARB), reduces serum uric acid levels. However, the effects of losartan on serum uric acid levels in the patients treated with a thiazide diuretic have not been fully elucidated. We have investigated the effects of losartan compared with other ARBs on blood variables and blood pressure control in hypertensive patients treated with a thiazide diuretic using data from the COMFORT study. The present analysis included a total of 118 hypertensive subjects on combination treatment with ARBs except for losartan and a diuretic who were randomly assigned to a daily regimen of a combination pill (losartan 50 mg/hydrochlorothiazide 12.5 mg) or to continuation of two pills, an ARB except for losartan and a diuretic. Blood pressures were evaluated at 1, 3, and 6 months after randomization and changes in blood variables including serum uric acid were evaluated during 6 months treatment period. Mean follow-up blood pressure levels were not different between the combination pill (losartan treatment) group and the control (ARBs except for losartan) group. On the other hand, serum uric acid significantly decreased in the combination pill group compared with the control group (-0.44 versus + 0.10 mg/dl; p = 0.01), although hematocrit, serum creatinine, sodium and potassium were not different between the groups. These results suggest that the treatment regimen switched from a combination therapy of ARBs except for losartan and a diuretic to a combination pill (losartan/ hydrochlorothiazide) decreases serum uric acid without affecting blood pressure control.

Hypertension, its treatment, hyperuricaemia and gout

PURPOSE OF REVIEW

Gout is increasing worldwide. An appreciation that hyperuricaemia and gout are associated with hypertension and chronic kidney disease is well established, but the cause and effect relationships are controversial. Studies which address this conundrum have been reviewed.

RECENT FINDINGS

Epidemiological surveys have confirmed the strong relationship of gout and hyperuricaemia with hypertension and diuretic treatment. There are multiple confounders such as obesity and alcohol consumption which despite adjustments make interpretation of the epidemiology difficult. There are data to suggest that hyperuricaemia itself causes hypertension and renovascular disease, and that lowering of serum urate may assist in control of hypertension. The mechanism for diuretic-induced hyperuricaemia may operate through volume depletion and reduced secretion of uric acid. The latter effect may be genetically influenced.

SUMMARY

Recent population surveys have strongly supported the association of gout and hyperuricaemia with hypertension. The prevailing explanation that renal dysfunction causes both phenomena or that they are caused by shared factors is challenged by the evidence that hyperuricaemia drives hypertension. A confounder of epidemiology studies is the use of diuretics for treating hypertension. A closer understanding of the mechanisms of diuretic-induced hyperuricaemia may lead to the creation of uricosuric diuretics. Losartan is exceptional amongst antihypertensive drugs in possessing mild uricosuric properties and therefore has a role in treating hypertensive patients with gout. Overcoming diuretic-induced hyperuricaemia is difficult and there is need for a uricosuric diuretic.

Angiotensin receptor blocker (ARB)-diuretic versus ARB-calcium channel blocker combination therapy for hypertension uncontrolled by ARB monotherapy

Diuretics or calcium channel blockers (CCBs) are used concomitantly with an angiotensin II receptor blocker (ARB). However, it is not established which ARB-based combination therapy is the most effective and safe. This prospective randomized open-label study compared the efficacy and safety of a fixed-dose tablet of losartan (LST)-hydrochlorothiazide (HCTZ) (n = 99) and LST-amlodipine (AML) (n = 77) in Japanese patients whose hypertension was uncontrolled by ARB monotherapy. Blood pressure changed similarly over the 12-month study period. Only LST-HCTZ significantly increased serum uric acid (SUA) in patients with low baseline SUA (<5.6 mg/dL) but not in patients with high baseline SUA.

Three-year safety and effectiveness of fixed-dose losartan/hydrochlorothiazide combination therapy in Japanese patients with hypertension under clinical setting (PALM-1 Extension Study)

Concerns about metabolic complications often disturb prolonged use of diuretics in Japan. We investigated 3-year safety and efficacy in Japanese patients with hypertension who were uncontrolled with angiotensin receptor blocker or angiotensin-converting enzyme inhibitor regimens and then switched to losartan (50 mg)/hydrochlorothiazide (12.5 mg; HCTZ) combinations. Blood pressure decreased favorably and maintained a steady state for 3 years (157 ± 16/88 ± 11 mm Hg to 132 ± 13/75 ± 9 mm Hg, P < .0001). Metabolic parameters maintained a limited range of changes after 3 years, and adverse events were markedly decreased after 1-year treatment. The losartan/HCTZ combination minimized diuretic-related adverse effects and thus may be useful for the treatment of Japanese patients with hypertension.