Dose and Time Effects of Renin-Angiotensin Inhibitors on Patients With Advanced Stages 4 to 5 of Diabetic Kidney Disease.

Context: Limited evidence exists regarding the cumulative dosing and duration impact of renin-angiotensin system inhibitors (RASis) on cardiorenal and mortality outcomes in patients with advanced stages (predominantly in stage 5 and a minority in stage 4) of diabetic kidney disease (DKD). Objective: To retrospectively investigate whether there are dose- and time-dependent relationships between RASis and cardiorenal and mortality outcomes in this population. Methods: Using Taiwan's national health insurance data in 2000-2017, we analyzed 2196 RASi users and 2196 propensity-matched nonusers among 8738 patients living with diabetes and newly diagnosed with advanced chronic kidney disease (23% stage 4, 77% stage 5). Cox proportional hazards regression models were used to estimate adjusted hazard ratios (aHRs) and 95% CI. Results: RASi use was significantly associated with reduced risks of all-cause mortality (aHR, 0.53; 95% CI 0.47-0.60) and cardiovascular mortality (0.68; 0.56-0.83) with the degree of benefit depending on therapeutic dosage and duration, despite a nonsignificant increase in acute kidney injury risk (1.16; 0.98-1.38) and a significant increase in hyperkalemia risk (1.45; 1.19-1.77). Significant differences in proteinuria risk (1.32; 1.21-1.43) were observed, while there were no significant differences in end-stage renal disease risk (1.01; 0.88-1.15) and no dose- or time-response relationships for either end-stage renal disease or proteinuria risks. Sensitivity analyses confirmed cardiovascular and survival benefits, even in patients with stage 5 DKD. Conclusion: This real-world study suggests that RASi use in advanced stages 4 to 5 DKD may provide dose- and time-dependent cardioprotection and improved survival, without excess renal harms.

Sudden-onset hypertension leading to the diagnosis of unilateral hydronephrosis due to ureteropelvic junction obstruction.

We present a case of a 41-year-old female who developed hypertension over a three-month period and was subsequently diagnosed with ureteropelvic junction obstruction (UPJO). The patient came to our department with elevated blood pressure. Blood examinations revealed normal renal function, hypokalemia and increased renin-angiotensin system (RAS) activity, as indicated by elevated level of plasma renin activity and plasma aldosterone level. A computed tomography imaging further revealed dilation of the left renal pelvis, atrophy of the left kidney, and indications of obstruction at the junction between the renal pelvis and ureter. Surgical intervention in the form of a left pyeloplasty successfully resolved the unilateral hydronephrosis, corrected the elevated RAS activity, normalized the blood pressure, and ameliorated the hypokalemia. This case emphasizes that elevated blood pressure might be the sole clinical indication of hydronephrosis. It's crucial to consider hydronephrosis due to UPJO as a potential cause, especially when diagnosing hypertension associated with RAS hyperactivity in young adults. It also highlights the effectiveness of surgical intervention in treating hypertension in such scenarios.

Hunting for protective drugs at the break of a pandemic: Causal inference from hospital data.

At the break of a pandemic, the protective efficacy of therapeutic interventions needs rapid evaluation. An experimental approach to the problem will not always be appropriate. An alternative route are observational studies, whether based on regional health service data or hospital records. In this paper, we discuss the use of methods of causal inference for the analysis of such data, with special reference to causal questions that may arise in a pandemic. We apply the methods by using the aid of a directed acyclic graph (DAG) representation of the problem, to encode our causal assumptions and to logically connect the scientific questions. We illustrate the usefulness of DAGs in the context of a controversy over the effects of renin aldosterone system inhibitors (RASIs) in hypertensive individuals at risk of (or affected by) severe acute respiratory syndrome coronavirus 2 disease. We consider questions concerning the existence and the directions of those effects, their underlying mechanisms, and the possible dependence of the effects on context variables. This paper describes the cognitive steps that led to a DAG representation of the problem, based on background knowledge and evidence from past studies, and the use of the DAG to analyze our hospital data and assess the interpretive limits of the results. Our study contributed to subverting early opinions about RASIs, by suggesting that these drugs may indeed protect the older hypertensive Covid-19 patients from the consequences of the disease. Mechanistic interaction methods revealed that the benefit may be greater (in a sense to be made clear) in the older stratum of the population.

Down-regulation of renin-aldosterone and antidiuretic hormone systems in patients with myalgic encephalomyelitis/chronic fatigue syndrome.

BACKGROUND: Central nervous system dysfunction associated with myalgic encephalomyelitis (ME) has been postulated as the cause of chronic fatigue syndrome (CFS). A small heart or reduced left ventricular volume with reduced cardiac output has been reported to be common in patients with ME. The main circulatory blood volume regulators may be down-regulated. METHODS: Plasma levels of the neurohumoral factors that regulate circulatory blood volume were determined in 18 patients with ME and 15 healthy subjects (Controls). RESULTS: The echocardiographic examination revealed that the mean values for the left ventricular end-diastolic diameters, stroke volume index, and cardiac index as well as the mean blood pressure were all significantly smaller in the ME group than in the Controls. The mean plasma renin activity (1.6±1.0ng/ml/h vs. 2.5±1.5ng/ml/h, p=0.06) was considerably lower in the ME group than in the Controls. Both the mean plasma aldosterone (104±37pg/ml vs. 157±67pg/ml, p=0.004) and antidiuretic hormone (ADH) (2.2±1.0pg/ml vs. 3.3±1.5pg/ml, p=0.02) concentrations were significantly lower in the ME group than in the Controls. Desmopressin (120µg), a synthetic version of arginine vasopressin, was orally administered for five successive days to 10 patients with ME. In five patients (50%), the symptoms of orthostatic intolerance during a 10min active standing test were ameliorated in association with a significant increase in urinary osmotic pressure and decrease in heart rate. Furthermore, in five patients (50%), the performance status scores for the activities of daily living were improved. CONCLUSIONS: Both the renin-aldosterone and ADH systems were down-regulated despite the existence of reduction in cardiac preload and output in patients with ME. Desmopressin improved symptoms in half of the patients.

Short-term add-on therapy with angiotensin receptor blocker for end-stage inotrope-dependent heart failure patients: B-type natriuretic peptide reduction in a randomized clinical trial

OBJECTIVE: We aimed to evaluate angiotensin receptor blocker add-on therapy in patients with low cardiac output during decompensated heart failure. METHODS: We selected patients with decompensated heart failure, low cardiac output, dobutamine dependence, and an ejection fraction <0.45 who were receiving an angiotensin-converting enzyme inhibitor. The patients were randomized to losartan or placebo and underwent invasive hemodynamic and B-type natriuretic peptide measurements at baseline and on the seventh day after intervention. ClinicalTrials.gov: NCT01857999. RESULTS: We studied 10 patients in the losartan group and 11 patients in the placebo group. The patient characteristics were as follows: age 52.7 years, ejection fraction 21.3%, dobutamine infusion 8.5 mcg/kg.min, indexed systemic vascular resistance 1918.0 dynes.sec/cm5.m2, cardiac index 2.8 L/min.m2, and B-type natriuretic peptide 1,403 pg/mL. After 7 days of intervention, there was a 37.4% reduction in the B-type natriuretic peptide levels in the losartan group compared with an 11.9% increase in the placebo group (mean difference, -49.1%; 95% confidence interval: -88.1 to -9.8%, p = 0.018). No significant difference was observed in the hemodynamic measurements. CONCLUSION: Short-term add-on therapy with losartan reduced B-type natriuretic peptide levels in patients hospitalized for decompensated severe heart failure and low cardiac output with inotrope dependence. .

Augentation of plasma atrial natriuretic peptide by hot water immersion in normal man / 日本温泉気候物理医学会雑誌

This study examined acute effects of hot water immersion on the secretion of human alpha-atrial natriuretic peptide (ANP), cyclic GMP (c-GMP), arginine vasopressin (AVP), plasma renin activity (PRA) and aldosterone in venous blood. Ten healthy subjects (mean age: 20.5yr.) underwent hot water immersion (IM) of 40°C for ten minutes by quiet sitting, which simulates usual bathing among Japanese. ANP rose from 19 to 34pg/ml with the peaked value at ten minutes of IM (p<0.001), and remained signifcantly elevated during 10 to 30 minutes after IM. Then they qradually returned to the pre-immersing level by 50min. c-GMP showed similar timed responeses as ANP. Between those parameters significantly positive linear correlation (p<0.001) was observed. AVP did not change immediately after IM, but tended to rise at 20 minutes after IM. PRA and aldosterone increased in rates of the changes later at 15 to 30 minutes, but less significantly as ANP. Those results suggested that the secretion of ANP by water immersion was enhanced by thermal stimuli in spite of short duration of central hypervolemia by water immersion. Suppressing effects of water immersion on AVP and renin-aldosterone system were small. On the contrary, hot water stimuli exerted rebounding increases on them. c-GMP seemed to be one of the indicative factors relating to the change of ANP.