494 research outputs found
Recommended from our members
Genetic Risk, Muscle Strength, and Incident Stroke: Findings From the UK Biobank Study.
OBJECTIVE: To examine the associations of muscle strength and genetic risk for stroke with stroke incidence. PARTICIPANTS AND METHODS: We included 284,767 white British participants of UK Biobank without genetic relatedness and stroke or myocardial infarction at baseline between March 13, 2006, and October 1, 2010. Genetic risk was assessed with polygenic risk scores, calculated by summing the risk-increasing alleles, weighted by the effect estimates. Muscle strength was assessed through grip strength tests by hand dynamometers. Incidence of overall (n= 4008), ischemic (n= 3031), and hemorrhagic (n=1073) stroke was adjudicated during 11.5-year follow-up. RESULTS: Compared with the bottom muscle strength tertile, hazard ratios (95% CI) of stroke were 0.81 (0.75 to 0.87) and 0.76 (0.71 to 0.82) for the middle and top muscle strength tertiles, respectively, after adjustment for confounders and genetic risk; higher genetic risk was independently associated with higher stroke incidence. Stroke hazards for the top muscle strength tertile were consistently lower across genetic risk strata, with no evidence of interaction. Compared with individuals with high muscle strength and low genetic risk, stroke hazards were higher for individuals who had medium or high genetic risk combined with low or medium muscle strength but not for those who had medium genetic risk but high muscle strength. Associations were similar for ischemic and hemorrhagic stroke (although CIs were inconclusive for some of the associations). CONCLUSION: Higher muscle strength was associated with lower stroke incidence in all individuals, including those with high genetic susceptibility. The increased genetic risk of overall and ischemic stroke was partly attenuated through increased muscle strength
Rolofylline, an adenosine A1−receptor antagonist, in acute heart failure
Background:
Worsening renal function, which is associated with adverse outcomes, often develops
in patients with acute heart failure. Experimental and clinical studies suggest that
counterregulatory responses mediated by adenosine may be involved. We tested the
hypothesis that the use of rolofylline, an adenosine A1−receptor antagonist, would
improve dyspnea, reduce the risk of worsening renal function, and lead to a more
favorable clinical course in patients with acute heart failure.
Methods:
We conducted a multicenter, double-blind, placebo-controlled trial involving patients
hospitalized for acute heart failure with impaired renal function. Within 24 hours
after presentation, 2033 patients were randomly assigned, in a 2:1 ratio, to receive
daily intravenous rolofylline (30 mg) or placebo for up to 3 days. The primary end
point was treatment success, treatment failure, or no change in the patient’s clinical
condition; this end point was defined according to survival, heart-failure status,
and changes in renal function. Secondary end points were the post-treatment development
of persistent renal impairment and the 60-day rate of death or readmission
for cardiovascular or renal causes.
Results:
Rolofylline, as compared with placebo, did not provide a benefit with respect to the
primary end point (odds ratio, 0.92; 95% confidence interval, 0.78 to 1.09; P=0.35).
Persistent renal impairment developed in 15.0% of patients in the rolofylline group
and in 13.7% of patients in the placebo group (P=0.44). By 60 days, death or readmission
for cardiovascular or renal causes had occurred in similar proportions of patients
assigned to rolofylline and placebo (30.7% and 31.9%, respectively; P=0.86).
Adverse-event rates were similar overall; however, only patients in the rolofylline
group had seizures, a known potential adverse effect of A1-receptor antagonists.
Conclusions:
Rolofylline did not have a favorable effect with respect to the primary clinical composite
end point, nor did it improve renal function or 60-day outcomes. It does not
show promise in the treatment of acute heart failure with renal dysfunction. (Funded
by NovaCardia, a subsidiary of Merck; ClinicalTrials.gov numbers, NCT00328692
and NCT00354458.
Predictors and associations with outcomes of length of hospital stay in patients with acute heart failure: results from VERITAS
Background:
The length of hospital stay (LOS) is important in patients admitted for acute heart failure (AHF) because it prolongs an unpleasant experience for the patients and adds substantially to health care costs.
Methods and Results:
We examined the association between LOS and baseline characteristics, 10-day post-discharge HF readmission, and 90-day post-discharge mortality in 1347 patients with AHF enrolled in the VERITAS program. Longer LOS was associated with greater HF severity and disease burden at baseline; however, most of the variability of LOS could not be explained by these factors. LOS was associated with a higher HF risk of both HF readmission (odds ratio for 1-day increase: 1.08; 95% confidence interval [CI] 1.01–1.16; P = .019) and 90-day mortality (hazard ratio for 1-day increase: 1.05; 95% CI 1.02–1.07; P < .001), although these associations are partially explained by concurrent end-organ damage and worsening heart failure during the first days of admission.
Conclusions:
In patients who have been admitted for AHF, longer length of hospital stay is associated with a higher rate of short-term mortality.
Clinical Trial Registration:
VERITAS-1 and -2: Clinicaltrials.gov identifiers NCT00525707 and NCT00524433
Systolic blood pressure reduction during the first 24 h in acute heart failure admission: friend or foe?
Aims:
Changes in systolic blood pressure (SBP) during an admission for acute heart failure (AHF), especially those leading to hypotension, have been suggested to increase the risk for adverse outcomes.
Methods and results:
We analysed associations of SBP decrease during the first 24 h from randomization with serum creatinine changes at the last time-point available (72 h), using linear regression, and with 30- and 180-day outcomes, using Cox regression, in 1257 patients in the VERITAS study. After multivariable adjustment for baseline SBP, greater SBP decrease at 24 h from randomization was associated with greater creatinine increase at 72 h and greater risk for 30-day all-cause death, worsening heart failure (HF) or HF readmission. The hazard ratio (HR) for each 1 mmHg decrease in SBP at 24 h for 30-day death, worsening HF or HF rehospitalization was 1.01 [95% confidence interval (CI) 1.00–1.02; P = 0.021]. Similarly, the HR for each 1 mmHg decrease in SBP at 24 h for 180-day all-cause mortality was 1.01 (95% CI 1.00–1.03; P = 0.038). The associations between SBP decrease and outcomes did not differ by tezosentan treatment group, although tezosentan treatment was associated with a greater SBP decrease at 24 h.
Conclusions:
In the current post hoc analysis, SBP decrease during the first 24 h was associated with increased renal impairment and adverse outcomes at 30 and 180 days. Caution, with special attention to blood pressure monitoring, should be exercised when vasodilating agents are given to AHF patients
A combined clinical and biomarker approach to predict diuretic response in acute heart failure
Background:
Poor diuretic response in acute heart failure is related to poor clinical outcome. The underlying mechanisms and pathophysiology behind diuretic resistance are incompletely understood. We evaluated a combined approach using clinical characteristics and biomarkers to predict diuretic response in acute heart failure (AHF).
Methods and results:
We investigated explanatory and predictive models for diuretic response—weight loss at day 4 per 40 mg of furosemide—in 974 patients with AHF included in the PROTECT trial. Biomarkers, addressing multiple pathophysiological pathways, were determined at baseline and after 24 h. An explanatory baseline biomarker model of a poor diuretic response included low potassium, chloride, hemoglobin, myeloperoxidase, and high blood urea nitrogen, albumin, triglycerides, ST2 and neutrophil gelatinase-associated lipocalin (r2 = 0.086). Diuretic response after 24 h (early diuretic response) was a strong predictor of diuretic response (β = 0.467, P < 0.001; r2 = 0.523). Addition of diuretic response after 24 h to biomarkers and clinical characteristics significantly improved the predictive model (r2 = 0.586, P < 0.001).
Conclusions:
Biomarkers indicate that diuretic unresponsiveness is associated with an atherosclerotic profile with abnormal renal function and electrolytes. However, predicting diuretic response is difficult and biomarkers have limited additive value. Patients at risk of poor diuretic response can be identified by measuring early diuretic response after 24 h
Serum potassium levels and outcome in acute heart failure (data from the PROTECT and COACH trials)
Serum potassium is routinely measured at admission for acute heart failure (AHF), but
information on association with clinical variables and prognosis is limited. Potassium
measurements at admission were available in 1,867 patients with AHF in the original cohort
of 2,033 patients included in the Patients Hospitalized with acute heart failure and Volume
Overload to Assess Treatment Effect on Congestion and Renal FuncTion trial. Patients
were grouped according to low potassium (<3.5 mEq/l), normal potassium (3.5 to 5.0 mEq/l),
and high potassium (>5.0 mEq/l) levels. Results were verified in a validation cohort of 1,023
patients. Mean age of patients was 71 – 11 years, and 66% were men. Low potassium was
present in 115 patients (6%), normal potassium in 1,576 (84%), and high potassium in 176
(9%). Potassium levels increased during hospitalization (0.18 – 0.69 mEq/l). Patients with
high potassium more often used angiotensin-converting enzyme inhibitors and mineralocorticoid
receptor antagonists before admission, had impaired baseline renal function and a
better diuretic response (p [ 0.005), independent of mineralocorticoid receptor antagonist
usage. During 180-day follow-up, a total of 330 patients (18%) died. Potassium levels at
admission showed a univariate linear association with mortality (hazard ratio [log] 2.36,
95% confidence interval 1.07 to 5.23; p [ 0.034) but not after multivariate adjustment.
Changes of potassium levels during hospitalization or potassium levels at discharge were
not associated with outcome after multivariate analysis. Results in the validation cohort
were similar to the index cohort. In conclusion, high potassium levels at admission are
associated with an impaired renal function but a better diuretic response. Changes in potassium
levels are common, and overall levels increase during hospitalization. In conclusion,
potassium levels at admission or its change during hospitalization are not associated
with mortality after multivariate adjustment
Changes in the ornithine cycle following ionising radiation cause a cytotoxic conditioning of the culture medium of H35 hepatoma cells
Cultured H35 hepatoma cells release a cytotoxic factor in response to irradiation with X-rays. When the conditioned medium from irradiated cells is given to nonirradiated cells, growth is inhibited and followed by cell death, possibly apoptosis, Analysis of the conditioned medium reveals a dramatic change in the ornithine (urea) cycle components after the irradiation. A strong decrease in medium arginine is accompanied with parallel increases in ornithine, citrulline and ammonia. The high level of ammonia appears to be largely responsible for the observed cytotoxicity. The development of hyperammonia by irradiated cells and the related toxicity depend on the radiation dose and the number of cells seeded thereafter for the medium conditioning. Development of cytotoxicity by irradiated cells is completely prevented with the arginase inhibitor L-norvaline, in arginine-deficient medium or when citrulline replaces arginine. These preventive measures result in subtoxic ammonia levels
Association of Rare Coding Mutations With Alzheimer Disease and Other Dementias Among Adults of European Ancestry
IMPORTANCE Some of the unexplained heritability of Alzheimer disease (AD) may be due to rare variants whose effects are not captured in genome-wide association studies because very large samples are needed to observe statistically significant associations.
OBJECTIVE To identify genetic variants associated with AD risk using a nonstatistical approach.
DESIGN, SETTING, AND PARTICIPANTS Genetic association study in which rare variants were identified by whole-exome sequencing in unrelated individuals of European ancestry from the Alzheimer’s Disease Sequencing Project (ADSP). Data were analyzed between March 2017 and September 2018.
MAIN OUTCOMES AND MEASURES Minor alleles genome-wide and in 95 genes previously associated with AD, AD-related traits, or other dementias were tabulated and filtered for predicted functional impact and occurrence in participants with AD but not controls. Support for several findings was sought in a whole-exome sequencing data set comprising 19 affected relative pairs from Utah high-risk pedigrees and whole-genome sequencing data sets from the ADSP and Alzheimer’s Disease Neuroimaging Initiative.
RESULTS Among 5617 participants with AD (3202 [57.0%] women; mean [SD] age, 76.4 [9.3] years) and 4594 controls (2719 [59.0%] women; mean [SD] age, 86.5 [4.5] years), a total of 24 variants with moderate or high functional impact from 19 genes were observed in 10 or more participants with AD but not in controls. These variants included a missense mutation (rs149307620 [p.A284T], n = 10) in NOTCH3, a gene in which coding mutations are associated with cerebral autosomal-dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL), that was also identified in 1 participant with AD and 1 participant with mild cognitive impairment in the whole genome sequencing data sets. Four participants with AD carried the TREM2 rs104894002 (p.Q33X) high-impact mutation that, in homozygous form, causes Nasu-Hakola disease, a rare disorder characterized by early-onset dementia and multifocal bone cysts, suggesting an intermediate inheritance model for the mutation. Compared with controls, participants with AD had a significantly higher burden of deleterious rare coding variants in dementia-associated genes (2314 vs 3354 cumulative variants, respectively; P = .006).
CONCLUSIONS AND RELEVANCE Different mutations in the same gene or variable dose of a mutation may be associated with result in distinct dementias. These findings suggest that minor differences in the structure or amount of protein may be associated with in different clinical outcomes. Understanding these genotype-phenotype associations may provide further insight into the pathogenic nature of the mutations, as well as offer clues for developing new therapeutic targets
The feeding route (enteral or parenteral) affects the plasma response of the dipetide Ala-Gln and the amino acids glutamine, citrulline and arginine, with the administration of Ala-Gln in preoperative patients
Prognostic significance of creatinine increases during an acute heart failure admission in patients with and without residual congestion
Background: The importance of a serum creatinine increase, traditionally considered worsening renal function (WRF), during admission for acute heart failure has been recently debated, with data suggesting an interaction between congestion and creatinine changes.
Methods and Results: In post hoc analyses, we analyzed the association of WRF with length of hospital stay, 30-day death or cardiovascular/renal readmission and 90-day mortality in the PROTECT study (Placebo-Controlled Randomized Study of the Selective A1 Adenosine Receptor Antagonist Rolofylline for Patients Hospitalized With Acute Decompensated Heart Failure and Volume Overload to Assess Treatment Effect on Congestion and Renal Function). Daily creatinine changes from baseline were categorized as WRF (an increase of 0.3 mg/dL or more) or not. Daily congestion scores were computed by summing scores for orthopnea, edema, and jugular venous pressure. Of the 2033 total patients randomized, 1537 patients had both available at study day 14. Length of hospital stay was longer and 30-day cardiovascular/renal readmission or death more common in patients with WRF. However, these were driven by significant associations in patients with concomitant congestion at the time of assessment of renal function. The mean difference in length of hospital stay because of WRF was 3.51 (95% confidence interval, 1.29–5.73) more days (P=0.0019), and the hazard ratio for WRF on 30-day death or heart failure hospitalization was 1.49 (95% confidence interval, 1.06–2.09) times higher (P=0.0205), in significantly congested than nonsignificantly congested patients. A similar trend was observed with 90-day mortality although not statistically significant.
Conclusions: In patients admitted for acute heart failure, WRF defined as a creatinine increase of ≥0.3 mg/dL was associated with longer length of hospital stay, and worse 30- and 90-day outcomes. However, effects were largely driven by patients who had residual congestion at the time of renal function assessment
- …