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Thomas M. Macdonald – One of the best experts on this subject based on the ideXlab platform.
Primary aldosteronism, diagnosed by the aldosterone to renin Ratio, is a common cause of hypertension.Clinical endocrinology, 2003Co-Authors: Pitt O. Lim, Thomas M. MacdonaldAbstract:
., 2002). Importantly,it has been clearly shown that controlling BP offers signiﬁcantbeneﬁts. A 5-mmHg reduction in the population diastolic BP over5 years is associated with a reduction in strokes of about 40%and cardiac events by about a quarter, highlighting the need foradequate BP control (Collins
Variation at the aldosterone synthase (CYP11B2) locus contributes to hypertension in subjects with a raised Aldosterone-to-Renin RatioThe Journal of clinical endocrinology and metabolism, 2002Co-Authors: Pitt O. Lim, Thomas M. Macdonald, Christine D. Holloway, Elaine C. Friel, Niall H. Anderson, Eleanor Dow, Roland T. Jung, Eleanor Davies, Robert Fraser, John M. C. ConnellAbstract:
The Aldosterone-to-Renin Ratio (ARR) is a marker of aldosterone activity in hypertension. We examined the relationship of the ARR to the distribution of two biallelic polymorphisms at the CYP11B2 gene locus. One polymorphism affects a putative steroidogenic factor-1 binding site (−344 T/C) in the 5′-regulatory region, whereas the other marker reflects replacement of the intron-2 from CYP11B2 with that from the neighboring gene encoding 11β-hydroxylase (CYP11B1; wild-type/conversion). We studied consecutive referrals to the Tayside hypertension clinic in 1998. Because the specificity of ARR (pmol/liter/ng/ml/h) for hyperaldosteronism increases with its threshold, ARRs of at least 750 and 1000 were used. A total of 375 patients were assessed; 86.9% had complete data. There were significant excesses of steroidogenic factor-1 (T) (ARR ≥ 750, 0.62 vs. 0.51, P = 0.014; ARR ≥ 1000, 0.63 vs. 0.51, P = 0.039) and intron-2 (conversion) (ARR ≥ 750, 0.49 vs. 0.41, P = 0.205; ARR ≥ 1000, 0.54 vs. 0.41, P = 0.029) alle…
The neurohormonal natural history of essential hypertension: towards primary or tertiary aldosteronism?Journal of hypertension, 2002Co-Authors: Pitt O. Lim, Allan D. Struthers, Thomas M. MacdonaldAbstract:
Use of the Aldosterone-to-Renin Ratio has controversially suggested that approximately 10% of hypertensives have primary aldosteronism, and most of these individuals are thought to have idiopathic hyperaldosteronism. The usual renin–angiotensin system control is intact in these individuals and is si
Taku Obara – One of the best experts on this subject based on the ideXlab platform.
Association of Aldosterone-to-Renin Ratio With Hypertension Differs by Sodium Intake: The Ohasama StudyAmerican journal of hypertension, 2014Co-Authors: Michihiro Satoh, Ryusuke Inoue, Masahiro Kikuya, Azusa Hara, Takuo Hirose, Hirohito Metoki, Miki Hosaka, Kei Asayama, Megumi Tsubota-utsugi, Taku ObaraAbstract:
background In cross-sectional studies, the Aldosterone-to-Renin Ratio (ARR) has been reported to be associated with hypertension under conditions of higher sodium intake. The objective of this prospective study was to investigate the association between ARR and the development of hypertension in community residents stratified by dietary sodium intake. methods From the general population of Ohasama, we obtained plasma renin activity (PRA) and plasma aldosterone concentRations (PACs) for 608 participants (mean age = 57.6 years; 71.4% women) without hypertension at baseline. Using the Cox model, we computed the adjusted hazard Ratio (HR) of natural log-transformed ARR (lnARR) for the development of hypertension, defined as blood pressure ≥140/90 mm Hg or start of treatment with antihypertensive drugs during follow-up. results During a mean follow-up of 6.8 years, 298 participants developed hypertension. The median PRA, PAC, and ARR were 1.2 ng/ml/hour, 6.6 ng/dl, and 5.5 ng/dl per ng/ml/hour, respectively. Each 1 SD increase in lnARR was associated with an increased risk for the development of hypertension in participants overall (HR = 1.18; P = 0.007). In participants with higher sodium intake (median ≥4,102 mg/day), a significant association of lnARR with hypertension remained (HR = 1.25; P = 0.009), whereas no significant association was observed in participants with lower sodium intake (P = 0.18). Participants who developed hypertension had significantly lower PRA than those who did not ( P = 0.003), despite no differences in PAC ( P = 0.91).
Aldosterone-to-Renin Ratio and nocturnal blood pressure decline assessed by self-measurement of blood pressure at home: the Ohasama Study.Clinical and experimental hypertension (New York N.Y. : 1993), 2014Co-Authors: Michihiro Satoh, Ryusuke Inoue, Masahiro Kikuya, Azusa Hara, Takuo Hirose, Hirohito Metoki, Miki Hosaka, Kei Asayama, Megumi Utsugi, Taku ObaraAbstract:
AbstractBased on ambulatory blood pressure (BP) monitoring, the Aldosterone-to-Renin Ratio (ARR) has been reported to be associated with a diminished nocturnal decline in BP, generally referred to as a “non-dipping” pattern. The objective of this cross-sectional study was to investigate the association between ARR and the non-dipping pattern based on home BP measurements. This study included 177 participants ≥55 years from the general population of Ohasama (mean age: 67.2 years; 74.6% women); no patient was receiving antihypertensive treatment. The median plasma renin activity (PRA), plasma aldosterone concentRation (PAC) and ARR were 0.8 ng/mL/h, 8.1 ng/dL and 9.7 ng/dL per ng/mL/h, respectively. Each 1 SD increase in log-transformed (ln) ARR was significantly associated with the prevalence of the non-dipping pattern after adjustments for possible confounding factors including home morning systolic BP (odds Ratio, 1.45; p = 0.049). However, no significant associations of PRA or PAC with the non-dipping p…
Aldosterone-to-Renin Ratio as a Predictor of Stroke Under Conditions of High Sodium Intake: The Ohasama StudyAmerican journal of hypertension, 2012Co-Authors: Michihiro Satoh, Masahiro Kikuya, Takayoshi Ohkubo, Takanao Hashimoto, Azusa Hara, Takuo Hirose, Hirohito Metoki, Megumi Utsugi, Takefumi Mori, Taku ObaraAbstract:
BACKGROUND Aldosterone is thought to have deleterious effects on the cardiovascular system. The Aldosterone-to-Renin Ratio (ARR) is more reproducible than aldosterone levels alone and could be an index for inappropriate aldosterone secretion or activity. We previously reported the apparent relation between ARR and hypertension in subjects with high sodium intake. This prospective study investigated the risk of ARR for a first stroke in a general population stratified by sodium intake. METHODS We obtained plasma renin activity (PRA) and plasma aldosterone concentRations (PAC) for 883 participants aged ≥ 35 years not receiving antihypertensive treatment in the general population of Ohasama (mean age: 59.0 ± 11.3 years; 65.6% women). RESULTS Over a mean of 10.9 follow-up years, 45 strokes occurred. The median PRA, PAC, and ARR were 1.2 ng/ml/h, 6.4 ng/dl, and 5.3 ng/dl per ng/ml/h, respectively. Using Cox regression, we computed hazard Ratios adjusted for sex, age, body mass index (BMI), and systolic blood pressure. No association between logARR and stroke was observed in subjects overall. However, in subjects with high sodium intake (≥ median of 4,058 mg/day (salt equivalent, 10.5 g/day)), each 1 s.d. increase in logARR was associated with an increased hazard Ratio for stroke (hazard Ratio: 1.49, P = 0.04). No significant association was observed in subjects with low sodium intake (P = 0.7). When we repeated all the analyses using logPRA or logPAC, no significant associations were found. CONCLUSION These results suggest that high ARR, that is, relative aldosterone excess, is a predictor for stroke under conditions of high sodium intake.
Oliviero Olivieri – One of the best experts on this subject based on the ideXlab platform.
Urinary prostasin in normotensive individuals : correlation with the aldosterone to renin Ratio and urinary sodiumHypertension research : official journal of the Japanese Society of Hypertension, 2013Co-Authors: Oliviero Olivieri, Francesca Pizzolo, Patrizia Guarini, Laura Chiecchi, Annalisa Castagna, Ricciarda Raffaelli, Muthukumar Gunasekaran, Letizia Consoli, Gian Luca Salvagno, Kenichiro KitamuraAbstract:
Prostasin, a glycosylphosphatidylinositol (GPI)-anchored serine protease, activates the epithelial sodium (Na) channel (ENaC), and prostasin is released in extracellular fluids, including urine. Previous data have suggested a direct association between urinary prostasin and the activation of an aldosterone-driven pathway, but a quantitative association has never been demonstrated in normotensive subjects. Similarly, physiological relationships with natriuresis or possible gender- or female hormone-related changes in urinary prostasin concentRations have never been investigated. We measured urinary prostasin by enzyme-linked immunosorbent assay in 43 healthy normotensive subjects of similar age presenting different urinary Na levels and in 15 women during the menstrual cycle and after oral estro-progestinic contraceptive (OC) therapy. Exosomal urinary prostasin was also estimated by western blotting of samples from six healthy subjects twice during the morning. Urinary prostasin presented a wide range of values (from 0.5 to 18.9 nM) without gender differences. It was positively correlated with the aldosterone to renin Ratio (ARR) but not with circulating aldosterone or renin individually. Urinary prostasin was directly correlated with U-Na levels (up to 200 nmol Na), whereas it decreased for higher Na concentRations. In women, no significant changes of prostasin concentRation were observed during menstrual phases. After OC therapy, prostasin increased (from 2.37±1.27 to 4.85±5.28 nM), although the increase was not statistically different (P=0.07). Prostasin was detectable in urinary exosomes and displayed a pattern similar to urinary prostasin in relation to urinary Na. In conclusion, urinary prostasin correlates with the ARR, and it is physiologically modulated by natriuresis in normotensive individuals.
Antihypertensive efficacy of spironolactone: what about sex?Journal of hypertension, 2011Co-Authors: Francesca Pizzolo, Oliviero OlivieriAbstract:
We read with interest the paper of Parthasarathy et al. , investigating the blood pressure (BP) response to two different diuretics [a mineralocorticoid receptor antagonist (MRA) and a thiazide diuretic] in patients subdivided, according to Aldosterone-to-Renin Ratio (ARR) value, in high and low ARR group, respectively. Given the high incidence of primary aldosteronism and the widely recognized adverse effects of aldosterone on cardiovascular system, further research on MRA use in hypertensive patients is warranted.
Effects of female sex hormones and contraceptive pill on the diagnostic work-up for primary aldosteronism.Journal of hypertension, 2010Co-Authors: Francesca Pizzolo, Chiara Pavan, Patrizia Guarini, Roberto Corrocher, Laura Chiecchi, Ricciarda Raffaelli, Alessia Memmo, Gian Cesare Guidi, Massimo Franchi, Oliviero OlivieriAbstract:
ObjectivesDue to the widespread use of the aldosterone to renin Ratio (ARR), primary aldosteronism is currently recognized as a frequent cause of secondary hypertension. After a positive screening, primary aldosteronism diagnosis needs confirmation by an inhibitory test such as intravenous saline lo