Comparative Effectiveness and Safety of Different Types of Inhaled Long-Acting ß2-Agonist Plus Inhaled Long-Acting Muscarinic Antagonist vs Inhaled Long-Acting ß2-Agonist Plus Inhaled Corticosteroid Fixed-Dose Combinations in COPD A Propensity Score-Inverse Probability of Treatment Weighting Cohort Study.

BACKGROUND: Despite multiple available fixed-dose combinations (FDCs) of inhaled long-acting ß2-agonists (LABAs) plus long-acting muscarinic antagonists (LAMAs) and LABAs plus inhaled corticosteroids (ICS) for COPD, uncertainty remains regarding their comparative effects. RESEARCH QUESTION: Can comparative effectiveness and safety of LABA plus LAMA (LABA/LAMA) and LABA plus ICS (LABA/ICS) FDCs vary by different individual components of the dual combinations in COPD? STUDY DESIGN AND METHODS: We conducted a new user, propensity score-inverse probability of treatment weighting cohort study to compare the effectiveness and safety of two frequently used LABA/LAMA FDCs (indacaterol plus glycopyrronium [IND/GLY] and vilanterol plus umeclidinium [VI/UMEC]) vs three commonly prescribed LABA/ICS FDCs (salmeterol plus fluticasone propionate [SAL/FP], formoterol fumarate plus budesonide [FF/BUD], and formoterol fumarate plus beclomethasone dipropionate [FF/BDP]) using the Taiwanese nationwide health care claims from 2014 through 2017. The primary effectiveness outcome was the annual moderate to severe exacerbation rate, and safety outcomes included risks of severe pneumonia and cardiovascular disease requiring hospitalization. Weighted generalized linear mixed models and Cox proportional hazard models were used to assess the effectiveness and safety outcomes, respectively. RESULTS: Patients with COPD initiating IND/GLY and VI/UMEC showed an 11% (incidence rate ratio [IRR], 0.89; 95% CI, 0.80-0.98) and 20% (IRR, 0.80; 95% CI, 0.71-0.90) reduced annual rate of moderate to severe exacerbations, respectively, than those initiating SAL/FP, but showed a similar rate as those initiating FF/BUD or FF/BDP. Both LABA/LAMA FDCs, compared with SAL/FP and VI/UMEC vs FF/BDP, were associated with a 27% (hazard ratio [HR], 0.73; 95% CI, 0.59-0.90) to 42% (HR, 0.58; 95% CI, 0.48-0.70) reduced pneumonia risk. Cardiovascular risk was comparable in five groups. An intraclass difference existed in rates of moderate to severe COPD exacerbation and risks of pneumonia among LABA/ICS FDCs, but not between LABA/LAMA FDCs. INTERPRETATION: Both LABA/LAMAs vs SAL/FP are associated with a lower exacerbation rate and pneumonia risk, but exhibit similar effectiveness and safety outcomes compared with FF/BDP or FF/BUD, suggesting that comparative effects may differ by individual components of the dual therapies in COPD.

A High Phosphorus Diet Impairs Testicular Function and Spermatogenesis in Male Mice with Chronic Kidney Disease.

Hyperphosphatemia is a serious complication in chronic kidney disease (CKD) that occurs due to insufficient excretion of phosphorus during failure of renal function. Both CKD and an excessive phosphorus intake have been reported to increase oxidative stress and result in poor male fertility, but little is known about the reproductive function of the CKD under a poorly controlled phosphate intake. Eight-week-old C57BL/6 mice (n = 66) were randomly divided into four groups: a sham operation group received a chow diet as control (SC group, n = 14), CKD-induced mice received a chow diet (CKDC group, n = 16), control mice received a high phosphorus (HP) diet (SP group, n = 16), and CKD-induced mice received a HP diet (CKDP group, n = 20). CKD was induced by performing a 5/6 nephrectomy. The chow diet contained 0.6% phosphorus, while the HP diet contained 2% phosphorus. Impaired testicular function and semen quality found in the CKD model may result from increased oxidative stress, causing apoptosis and inflammation. The HP diet aggravated the negative effects of testicular damage in the CKD-induced mice.

Antiproteinuria Effect of Calcitriol in Patients With Chronic Kidney Disease and Vitamin D Deficiency: A Randomized Controlled Study.

OBJECTIVE: Vitamin D has been demonstrated to lessen proteinuria severity in chronic kidney disease (CKD). Compared with healthy populations, patients with CKD may have lower serum levels of 1,25-dihydroxy vitamin D (1,25-(OH)2 D) and 25-hydroxy vitamin D (25-(OH) D). We investigated the effect of  oral low-dose active vitamin D (calcitriol at 0.25 µg, 3 times weekly) on urinary protein excretion. DESIGN AND METHODS: We conducted a nonblinded and non-placebo-controlled study. In total, 60 patients with CKD (average estimated glomerular filtration rate of >15 mL/min) who received a stable dose of angiotensin receptor blocker (ARB) or angiotensin-converting enzyme inhibitor (ACEI) were enrolled in this 24-week study. We randomly assigned these patients to the vitamin D group (oral calcitriol at 0.25 µg 3 times weekly with an ACEI or ARB) or the control group (ACEI or ARB). Change in the urine protein/creatinine ratio (uPCR) was the primary endpoint in this study. RESULTS: The mean baseline uPCRs of the 2 groups were comparable (1.84 ± 0.83 g/g vs. 2.02 ± 0.97 g/g, control vs. vitamin D group; P = .46). After the 24-week treatment, the uPCRs were significantly lower than the baseline values in the vitamin D group (1.35 ± 0.64 g/g; P < .05) but not in the control group. The values of uPCR decreased significantly at 8, 16, and 24 weeks (P < .05 vs. baseline) in the vitamin D group. The values of uPCRs were significantly lower in the vitamin D group than in the control group at 8, 16, and 24 weeks (P < .05). A positive correlation was discovered between reduction in uPCRs at 24-week and baseline 25-(OH) D serum level in the vitamin D group (r = 0.738, P < .001). CONCLUSION: Supplementary low-dose active vitamin D could reduce proteinuria in CKD patients with low serum 25-(OH) D levels.

Identification of the Causes for Chronic Hypokalemia: Importance of Urinary Sodium and Chloride Excretion.

BACKGROUND: Uncovering the correct diagnosis of chronic hypokalemia with potassium (K+) wasting from the kidneys or gut can be fraught with challenges. We identified clinical and laboratory parameters helpful for differentiating the causes of chronic hypokalemia. METHODS: Normotensive patients referred to our tertiary academic medical center for the evaluation of chronic hypokalemia were prospectively enrolled over 5 years. Clinical features, laboratory examinations-including blood and spot urine electrolytes, acid-base status, biochemistries, and hormones-as well as genetic analysis, were determined. RESULTS: Ninety-nine patients with chronic normotensive hypokalemia (serum K+ 2.8 ± 0.4 mmol/L, duration 4.1 ± 0.9 years) were enrolled. Neuromuscular symptoms were the most common complaints. Although Gitelman syndrome (n = 33), Bartter syndrome (n = 10), and distal renal tubular acidosis (n = 12) were the predominant renal tubular disorders, 44 patients (44%) were diagnosed with anorexia/bulimia nervosa (n = 21), surreptitious use of laxatives (n = 11), or diuretics (n = 12). Patients with gastrointestinal causes and surreptitious diuretics use exhibited a female predominance, lower body mass index, and less K+ supplementation. High urine K+ excretion (transtubular potassium gradient >3, urine K+/Cr >2 mmol/mmol) was universally present in patients with renal tubular disorders, but also found in >50% patients with gastrointestinal causes. Of interest, while urine sodium (Na+) and chloride (Cl-) excretions were high and coupled (urine Na+/Cl- ratio ∼1) in renal tubular disorders and "on" diuretics use, skewed or uncoupled urine Na+ and Cl- excretions were found in anorexia/bulimia nervosa and laxatives abuse (urine Na+/Cl- ratio: 5.0 ± 2.2, 0.4 ± 0.2, respectively) and low urine Na+ and Cl- excretions with fixed Na+/Cl- ratios (0.9 ± 0.2) when "off" diuretics. CONCLUSION: Besides body mass index, sex, and blood acid-base status, integrated interpretation of the urine Na+:Cl- excretion and their ratio is important to make an accurate diagnosis and treatment plan for patients with chronic normotensive hypokalemia.

CB1 cannabinoid receptor antagonist attenuates left ventricular hypertrophy and Akt-mediated cardiac fibrosis in experimental uremia.

Cannabinoid receptor type 1 (CB1R) plays an important role in the development of myocardial hypertrophy and fibrosis-2 pathological features of uremic cardiomyopathy. However, it remains unknown whether CB1R is involved in the pathogenesis of uremic cardiomyopathy. Here, we aimed to elucidate the role of CB1R in the development of uremic cardiomyopathy via modulation of Akt signalling. The heart size and myocardial fibrosis were evaluated by echocardiography and immunohistochemical staining, respectively, in 5/6 nephrectomy chronic kidney disease (CKD) mice treated with a CB1R antagonist. CB1R and fibrosis marker expression levels were determined by immunoblotting in H9c2 cells exposed to the uremic toxin indoxyl sulfate (IS), with an organic anion transporter 1 inhibitor or a CB1R antagonist or agonist. Akt phosphorylation was also assessed to examine the signaling pathways downstream of CB1R activation induced by IS in H9c2 cells. CKD mice exhibited marked left ventricular hypertrophy and myocardial fibrosis, which were reversed by treatment with the CB1R antagonist. CB1R, collagen I, transforming growth factor (TGF)-ß, and α-smooth muscle actin (SMA) expression showed time- and dose-dependent upregulation in H9c2 cells treated with IS. The inhibition of CB1R by either CB1R antagonist or small interfering RNA-mediated knockdown attenuated the expression of collagen I, TGF-ß, and α-SMA in IS-treated H9c2 cells, while Akt phosphorylation was enhanced by CB1R agonist and abrogated by CB1R antagonist in these cells. In summary, we conclude that CB1R blockade attenuates LVH and Akt-mediated cardiac fibrosis in a CKD mouse model. Uremic toxin IS stimulates the expression of CB1R and fibrotic markers and CB1R inhibition exerts anti-fibrotic effects via modulation of Akt signaling in H9c2 myofibroblasts. Therefore, the development of drugs targeting CB1R may have therapeutic potential in the treatment of uremic cardiomyopathy.

Etiologic and therapeutic analysis in patients with hypokalemic nonperiodic paralysis.

BACKGROUND: Hypokalemic nonperiodic paralysis represents a group of heterogeneous disorders with a large potassium (K(+)) deficit. Rapid diagnosis of curable causes with appropriate treatment is challenging to avoid the sequelae of hypokalemia. We prospectively analyzed the etiologies and therapeutic characteristics of hypokalemic nonperiodic paralysis. METHODS: Over an 8-year period, patients with hypokalemic nonperiodic paralysis were enrolled by excluding those with hypokalemic periodic paralysis due to acute shift of K(+) into cells. Blood and spot urine samples were collected for the measurements of electrolytes, pH, and biochemistries. Intravenous potassium chloride (KCl) at a rate of 10-20 mmol/h was administered until muscle strength recovered. RESULTS: We had identified 58 patients with hypokalemic nonperiodic paralysis from 208 consecutive patients with hypokalemic paralysis, and their average K(+) concentration was 1.8 ± 0.2 mmol/L. Among patients with low urinary K(+) excretion (n = 17), chronic alcoholism, remote diuretic use, and anorexia/bulimia nervosa were the most common causes. Among patients with high urinary K(+) excretion (n = 41) and metabolic acidosis, renal tubular acidosis and chronic toluene abuse were the main causes, while primary aldosteronism, Gitelman syndrome, and diuretics were the leading diagnoses with metabolic alkalosis. The average KCl dose needed to restore muscle strength was 3.8 ± 0.8 mmol/kg. Initial lower plasma K(+), volume depletion, and high urinary K(+) excretion were associated with higher recovery KCl dosage. During therapy, patients with paradoxical hypokalemia (n = 32) who required more KCl supplementation than patients without (4.1 ± 0.7 vs 3.4 ± 0.7 mmol/kg, P < 0.001) often exhibited significantly higher plasma renin activity and received a higher volume of normal saline before its appearance. CONCLUSIONS: Understanding the common etiologies of hypokalemic nonperiodic paralysis may aid in early diagnosis. Patients with initial lower plasma K(+), renal K(+) wasting, and hypovolemia required higher recovery K(+) dosage. Paradoxical hypokalemia is prone to develop in hypovolemic patients even during K(+) supplementation with volume repletion.

Osthole improves an accelerated focal segmental glomerulosclerosis model in the early stage by activating the Nrf2 antioxidant pathway and subsequently inhibiting NF-κB-mediated COX-2 expression and apoptosis.

Inflammatory reactions and oxidative stress are implicated in the pathogenesis of focal segmental glomerulosclerosis (FSGS), a common chronic kidney disease with relatively poor prognosis and unsatisfactory treatment regimens. Previously, we showed that osthole, a coumarin compound isolated from the seeds of Cnidium monnieri, can inhibit reactive oxygen species generation, NF-κB activation, and cyclooxygenase-2 expression in lipopolysaccharide-activated macrophages. In this study, we further evaluated its renoprotective effect in a mouse model of accelerated FSGS (acFSGS), featuring early development of proteinuria, followed by impaired renal function, glomerular epithelial cell hyperplasia lesions (a sensitive sign that precedes the development of glomerular sclerosis), periglomerular inflammation, and glomerular hyalinosis/sclerosis. The results show that osthole significantly prevented the development of the acFSGS model in the treated group of mice. The mechanisms involved in the renoprotective effects of osthole on the acFSGS model were mainly a result of an activated Nrf2-mediated antioxidant pathway in the early stage (proteinuria and ischemic collapse of the glomeruli) of acFSGS, followed by a decrease in: (1) NF-κB activation and COX-2 expression as well as PGE2 production, (2) podocyte injury, and (3) apoptosis. Our data support that targeting the Nrf2 antioxidant pathway may justify osthole being established as a candidate renoprotective compound for FSGS.

Hypokalemic paralysis in a young obese female.

BACKGROUND: Profound hypokalemia with paralysis usually poses a diagnostic and therapeutic challenge. METHODS: We report on a 28-y-old obese Chinese female presenting with sudden onset of flaccid quadriparesis upon awaking in the morning. There is no family history of hyperthyroidism. She experienced body weight loss of 7 kg in 2 months. RESULTS: The most conspicuous blood biochemistry is marked hypokalemia (1.8 mmol/l) and hypophosphatemia (0.5 mmol/l) associated with low urine K(+) and phosphate excretion. Surreptitious laxatives and/or diuretics abuse-related hypokalemic paralysis were tentatively made. However, her relatively normal blood acid-base status and the absence of low urine Na(+) and/or Cl(-) excretion made these diagnoses unlikely. Furthermore, she developed rebound hyperkalemia (5.7 mmol/l) after only 80 mmol K(+) supplementation. Thyroid function test confirmed hyperthyroidism due to Graves' disease. Control of the hyperthyroidism completely abolished her periodic paralysis. CONCLUSIONS: Thyrotoxic periodic paralysis (TPP) should be kept in mind as a cause of paralysis in female, even with obesity, despite its predominance in adult males.

(S)-armepavine from Chinese medicine improves experimental autoimmune crescentic glomerulonephritis.

OBJECTIVE: Intra-renal T cells and macrophages play a key pathogenic role in the development and progression of glomerular crescents. We aimed to establish (S)-armepavine [(S)-ARM], a major bioactive compound of a Chinese medicinal plant, Nelumbo nucifera, as a potential therapeutic agent in the treatment of autoimmune crescentic glomerulonephritis (ACGN). METHODS: A mouse ACGN model associated with T-cell dysregulation, was used to evaluate the therapeutic effects of (S)-ARM on the rapidly progressive glomerular disorder. RESULTS: The results showed that (S)-ARM administered in the established phase of ACGN is capable of dramatically decreasing glomerular crescents in the kidney and improving proteinuria and renal dysfunction. These effects were associated with greatly inhibited infiltration of T cells/macrophages and suppressed nuclear factor (NF)-κB activation in the kidney, lowered serum levels of autoantibodies and both serum and intra-renal levels of pro-inflammatory cytokines, suppressed T/B-cell activation and T-cell proliferation of the spleen, reduced glomerular immune deposits and apoptosis in both the spleen and kidney in (S)-ARM-treated ACGN mice, compared with the vehicle-treated (disease control) group of ACGN mice. CONCLUSION: We demonstrated therapeutic effects of (S)-ARM on ACGN as a result of: (i) early systemic negative modulation of T/B cells; (ii) intra-renal regulation of combined NF-κB activation and mononuclear leucocytic infiltration, thereby preventing glomerular crescent formation; and (iii) protection from apoptosis in both the spleen and kidney.

Therapeutic analysis in Chinese patients with thyrotoxic periodic paralysis over 6 years.

OBJECTIVE: To characterize the course of therapy in a large cohort of Chinese patients with thyrotoxic periodic paralysis (TPP), a reversible electrolyte emergency fraught with therapeutic challenges. DESIGN AND METHODS: In this prospective interventional study, 78 patients with TPP (75 males and three females with an age range of 16-48 years) were consecutively enrolled over a 6-year period. Intravenous KCl at a rate of 10 mmol/h was administered until muscle strength recovered. Serum potassium (K(+)) and phosphorus concentrations were measured hourly during the paralytic attack and for 6 h after recovery. RESULTS: The serum potassium (K(+)) on attack was 2.1+/-0.2 mmol/l. The dose of KCl administered to restore muscle strength was 63+/-32 mmol, and peak serum K(+) concentration after recovery was 5.3+/-0.5 mmol/l. A paradoxical fall in serum K(+) concentration >0.1 mmol/l difference between presentation and treatment nadir was observed in approximately one-fourth of TPP patients (n=20). These patients had significantly higher serum-free thyroxine concentration, systolic blood pressure, and heart rate on presentation, as well as serum phosphate concentration on recovery. They not only needed much more KCl supplementation (104+/-34 vs 48+/-19 mmol, P<0.001), but also had significantly more severe rebound hyperkalemia (5.8+/-0.5 vs 5.1+/-0.4 mmol/l, P<0.001) on recovery than those who did not have paradoxical hypokalemia. There was a positive correlation between the dose of KCl administered and the difference between peak and nadir serum K(+) (Delta K(+)) (r=0.68, P<0.001). CONCLUSIONS: TPP patients who do not develop paradoxical hypokalemia need a smaller KCl dose to achieve recovery, whereas those who develop paradoxical hypokalemia have more severe hyperthyroidism and hyperadrenergic activity and may require blockage of intracellular K(+) shift to prevent rebound hyperkalemia.

Hypocalciuria in patients with Gitelman syndrome: role of blood volume.

BACKGROUND: Hypocalciuria is common in patients with Gitelman syndrome (GS), and its cause primarily is enhanced renal reabsorption of calcium in the proximal tubule in response to hypovolemia, judged by recent studies in animals. STUDY DESIGN: Uncontrolled trial in cases and controls to evaluate the effect of acute reexpansion of extracellular fluid volume (ECFV) on urine calcium excretion in patients with GS. SETTING & PARTICIPANTS: 8 patients with GS and 8 sex- and age-matched healthy control subjects (CSs) were enrolled in an academic medical center. PREDICTOR: ECFV expansion with isotonic saline at 1 L/h for 3 hours. OUTCOMES & MEASUREMENTS: Urinary calcium excretion was measured hourly for 6 hours, and subsequent 18-hour urine was analyzed as a single collection; hormones and electrolytes were measured. RESULTS: Patients with GS had hypokalemia, metabolic alkalosis, hypomagnesemia, severe hypocalciuria (urine calcium-creatinine ratio, 0.006 +/- 0.002 versus 0.08 +/- 0.02 mg/mg [0.02 +/- 0.01 versus 0.22 +/- 0.05 mmol/mmol]; P < 0.005), and a mild degree of ECFV contraction. Sodium excretion and creatinine clearance rates were similar to those in CSs. In patients with GS, saline infusion increased ECFV, which caused a significantly greater sodium excretion rate, but there was only a small increase in calcium excretion rate, in both the first 6 hours (0.04 +/- 0.02 mg/min [1.0 +/- 0.6 micromol/min]) and subsequent 18-hour period (0.02 +/- 0.01 mg/min [0.4 +/- 0.2 micromol/min]), as in CSs. Notwithstanding, their calcium excretion rate was still much less than that in CSs before volume repletion (0.13 +/- 0.04 mg/min [3.2 +/- 1.0 micromol/min]). LIMITATION: Patients with GS did not become euvolemic on a long-term sodium chloride supplementation because they excreted sodium chloride so rapidly. CONCLUSION: Hypovolemia is not the sole cause of hypocalciuria in patients with GS.

Life-threatening hypokalemia in an asthmatic patient treated with high-dose hydrocortisone.

Although modest hypokalemia is frequently observed in asthmatic patients being treated with bronchodilators, profound hypokalemia and metabolic alkalosis are rarely reported in patients receiving high-dose hydrocortisone (HC). We describe a 66-year-old man who complained of generalized muscle weakness, shallow respiration, and palpitations after receiving high-dose intravenous HC (total dose, 2400 mg over 4 days) to treat a severe asthma attack. During this therapy, there was a weight gain of 1.0 kg. An electrocardiogram revealed ventricular arrhythmia with frequent premature ventricular contractions. Hypokalemia was profound, with plasma potassium (K+) concentration of 1.7 mEq/L, and associated with renal potassium wasting, as evidenced by a transtubular potassium concentration gradient of 12; metabolic alkalosis (plasma HCO3-, 37 mEq/L) was also present. When treated with spironolactone, KCl supplementation, and substitution of HC with prednisolone, his plasma K+ concentration rapidly normalized, metabolic alkalosis was corrected, and arrhythmia disappeared within 3 days. Because of unwanted mineralocorticoid side-effects, high-dose HC may cause life-threatening hypokalemia in asthmatic patients. Because of these potential risks, plasma acid-base and electrolyte concentrations should be monitored frequently in any patient treated with high-dose HC.

Effects of potassium supplementation on the recovery of thyrotoxic periodic paralysis.

Potassium supplements have been recommended to hasten recovery and prevent cardiopulmonary complications in patients with thyrotoxic periodic paralysis (TPP). However, this recommendation has not yet been proven efficacious. Thirty-two patients with acute attacks of TPP over a 3-year-period were divided into 2 groups. Group A (n = 12) was a control group treated with normal saline infusion 125 mL/hr only. Group B (n = 20) received intravenous KCl administration at a rate of 10 mmol/hr in normal saline 125 mL/hr. During the attack and for 6 hours after muscle recovery, hemodynamics were continuously recorded and muscle strength and plasma K(+) concentration were measured hourly. The sex, age, muscle strength, thyroid function, biochemical values including plasma K(+) levels, as well as the time from attack to therapy (3.6 +/- 1.6 v 3.3 +/- 1.0 hr) were not significant between the 2 groups. However, recovery time was significantly shorter in the KCl group than the control (6.3 +/- 3.8 v 13.5 +/- 7.5 hr, P < .01). Rebound hyperkalemia greater than 5.5 mmol/L occurred in 40% patients receiving KCl. The dose of KCl administered and peak K(+) concentration were positively correlated (r = 0.85, P < .001). In conclusion, KCl therapy proves to help the recovery of paralysis in TPP associated with rebound hyperkalemia. KCl supplementation should be given as small as possible (<10 mmol/hr) to avoid rebound hyperkalemia unless there are cardiopulmonary complications.