6 research outputs found
Appearance of innermost stable circular orbits of accretion discs around rotating neutron stars
The innermost stable cicular orbit (ISCO) of an accretion disc orbiting a
neutron star (NS) is often assumed a unique prediction of general relativity.
However, it has been argued that ISCO also appears around highly elliptic
bodies described by Newtonian theory. In this sense, the behaviour of an ISCO
around a rotating oblate neutron star is formed by the interplay between
relativistic and Newtonian effects. Here we briefly explore the consequences of
this interplay using a straightforward analytic approach as well as numerical
models that involve modern NS equations of state. We examine the ratio K
between the ISCO radius and the radius of the neutron star. We find that, with
growing NS spin, the ratio K first decreases, but then starts to increase. This
non-monotonic behaviour of K can give rise to a neutron star spin interval in
which ISCO appears for two very different ranges of NS mass. This may strongly
affect the distribution of neutron stars that have an ISCO (ISCO-NS). When
(all) neutron stars are distributed around a high mass M0, the ISCO-NS spin
distribution is roughly the same as the spin distribution corresponding to all
neutron stars. In contrast, if M0 is low, the ISCO-NS distribution can only
have a peak around a high value of spin. Finally, an intermediate value of M0
can imply an ISCO-NS distribution divided into two distinct groups of slow and
fast rotators. Our findings have immediate astrophysical applications. They can
be used for example to distinguish between different models of high-frequency
quasiperiodic oscillations observed in low-mass NS X-ray binaries.Comment: 4 pages, 2 figures, accepted by A&A Letter
Effect of sitagliptin on cardiovascular outcomes in type 2 diabetes
BACKGROUND: Data are lacking on the long-term effect on cardiovascular events of adding sitagliptin, a dipeptidyl peptidase 4 inhibitor, to usual care in patients with type 2 diabetes and cardiovascular disease. METHODS: In this randomized, double-blind study, we assigned 14,671 patients to add either sitagliptin or placebo to their existing therapy. Open-label use of antihyperglycemic therapy was encouraged as required, aimed at reaching individually appropriate glycemic targets in all patients. To determine whether sitagliptin was noninferior to placebo, we used a relative risk of 1.3 as the marginal upper boundary. The primary cardiovascular outcome was a composite of cardiovascular death, nonfatal myocardial infarction, nonfatal stroke, or hospitalization for unstable angina. RESULTS: During a median follow-up of 3.0 years, there was a small difference in glycated hemoglobin levels (least-squares mean difference for sitagliptin vs. placebo, -0.29 percentage points; 95% confidence interval [CI], -0.32 to -0.27). Overall, the primary outcome occurred in 839 patients in the sitagliptin group (11.4%; 4.06 per 100 person-years) and 851 patients in the placebo group (11.6%; 4.17 per 100 person-years). Sitagliptin was noninferior to placebo for the primary composite cardiovascular outcome (hazard ratio, 0.98; 95% CI, 0.88 to 1.09; P<0.001). Rates of hospitalization for heart failure did not differ between the two groups (hazard ratio, 1.00; 95% CI, 0.83 to 1.20; P = 0.98). There were no significant between-group differences in rates of acute pancreatitis (P = 0.07) or pancreatic cancer (P = 0.32). CONCLUSIONS: Among patients with type 2 diabetes and established cardiovascular disease, adding sitagliptin to usual care did not appear to increase the risk of major adverse cardiovascular events, hospitalization for heart failure, or other adverse events
CAPTURE: a cross-sectional study of the contemporary (2019) prevalence of cardiovascular disease in adults with type 2 diabetes across 13 countries
Contemporary use of diabetes medications with a cardiovascular indication in adults with type 2 diabetes: a secondary analysis of the multinational CAPTURE study
Effect of sitagliptin on cardiovascular outcomes in type 2 diabetes
BACKGROUND
Data are lacking on the long-term effect on cardiovascular events of adding sitagliptin,
a dipeptidyl peptidase 4 inhibitor, to usual care in patients with type 2
diabetes and cardiovascular disease.
METHODS
In this randomized, double-blind study, we assigned 14,671 patients to add either
sitagliptin or placebo to their existing therapy. Open-label use of antihyperglycemic
therapy was encouraged as required, aimed at reaching individually appropriate
glycemic targets in all patients. To determine whether sitagliptin was noninferior
to placebo, we used a relative risk of 1.3 as the marginal upper boundary. The
primary cardiovascular outcome was a composite of cardiovascular death, nonfatal
myocardial infarction, nonfatal stroke, or hospitalization for unstable angina.
RESULTS
During a median follow-up of 3.0 years, there was a small difference in glycated
hemoglobin levels (least-squares mean difference for sitagliptin vs. placebo,
120.29 percentage points; 95% confidence interval [CI], 120.32 to 120.27). Overall,
the primary outcome occurred in 839 patients in the sitagliptin group (11.4%;
4.06 per 100 person-years) and 851 patients in the placebo group (11.6%; 4.17 per
100 person-years). Sitagliptin was noninferior to placebo for the primary composite
cardiovascular outcome (hazard ratio, 0.98; 95% CI, 0.88 to 1.09; P<0.001).
Rates of hospitalization for heart failure did not differ between the two groups
(hazard ratio, 1.00; 95% CI, 0.83 to 1.20; P=0.98). There were no significant
between-group differences in rates of acute pancreatitis (P=0.07) or pancreatic
cancer (P=0.32).
CONCLUSIONS
Among patients with type 2 diabetes and established cardiovascular disease, adding
sitagliptin to usual care did not appear to increase the risk of major adverse cardiovascular
events, hospitalization for heart failure, or other adverse events.
(Funded by Merck Sharp & Dohme; TECOS ClinicalTrials.gov number, NCT00790205.