9 research outputs found
Aerosol Optical Retrieval and Surface Reflectance from Airborne Remote Sensing Data over Land
Quantitative analysis of atmospheric optical properties and surface reflectance can be performed by applying radiative transfer theory in the Atmosphere-Earth coupled system, for the atmospheric correction of hyperspectral remote sensing data. This paper describes a new physically-based algorithm to retrieve the aerosol optical thickness at 550nm (Ï550) and the surface reflectance (Ï) from airborne acquired data in the atmospheric window of the Visible and Near-Infrared (VNIR) range. The algorithm is realized in two modules. Module A retrieves Ï550 with a minimization algorithm, then Module B retrieves the surface reflectance Ï for each pixel of the image. The method was tested on five remote sensing images acquired by an airborne sensor under different geometric conditions to evaluate the reliability of the method. The results, Ï550 and Ï, retrieved from each image were validated with field data contemporaneously acquired by a sun-sky radiometer and a spectroradiometer, respectively. Good correlation index, r, and low root mean square deviations, RMSD, were obtained for the Ï550 retrieved by Module A (r2 = 0.75, RMSD = 0.08) and the Ï retrieved by Module B (r2 †0.9, RMSD †0.003). Overall, the results are encouraging, indicating that the method is reliable for optical atmospheric studies and the atmospheric correction of airborne hyperspectral images. The method does not require additional at-ground measurements about at-ground reflectance of the reference pixel and aerosol optical thickness
Association of CTLA-4 gene variants with response to therapy and long-term survival in metastatic melanoma patients treated with ipilimumab: An Italian melanoma intergroup study
Very Elderly Patients with Chronic Phase-Chronic Myeloid Leukemia on Imatinib: No Impact of Concomitant Drugs on Complete Cytogenetic Response
Tyrosine-kinase inhibitors (TKIs)have completely changed the expected survival of chronic myeloid leukemia (CML) patients which is now approaching that of the general population: a relevant proportion of CML patients are currently elderly or very elderly. Very elderly patients represent generally a small proportion in published experiences. Older CML patients imatinib treated, as it happens in the general population, receive other drug treatments for associated chronic illnesses. Our aim is to assess if and which classes of concomitant drugs have an impact on cytogenetic response in chronic phase (CP)-CML very elderly (age >75 years) patients.
Two hundred and twelve very elderly CP-CML patients, imatinib treated at 33 italian hematological institutions have been retrospectively evaluated. Median age at diagnosis was 78.5 years (range 75.0-93.0); 111 (52.4%) were male. Sixty-two (29.2%) were Sokal high risk. Sixty-seven (31.8%) were treated with reduced dose imatinib (400 mg/day. Concomitant drugs were 1-2 in 73 (34.4%) patients, 3-4 in 59 (27.8%), and >5 in 64 (30.2%); 16 (7.6%) did not assume any concomitant drug. Drugs more frequently used were antiplatelets, assumed by 104 (49.1%) patients, followed by diuretics in 91 (42.9%) patients, proton pump inhibitors (PPIs) in 86 (40.6%), ACE inhibitors in 55 (25.9%), beta blockers in 44 (20.7%), angiotensin II receptors blockers (ARB) in 41 (19.3%), calcium channel blockers in 34 (16%), statins in 25 (11.8%), and alpha blockers in 11 (5.2%).
Univariate logistic regression models were computed to assess the association between cytogenetic response after 6 or 12 months of imatinib treatment and number of concomitant drugs or selected drug classes. Statistical analyses were done using JMP 11.1 (SAS Institute Inc., Cary, NC, USA).
Complete cytogenetic response (CCyR) was obtained in 124 (58.8%) patients, of whom 70 (33%) within 6 months. Consequently, we focused our study on the impact of number and types of drugs on CCyR rate, which represents the primary therapeutic endpoint in the elderly. Cytogenetic response distribution according to concomitant drugs is reported in table 1.
We did not find any significant correlation between number of concomitant drugs, single classes of antihypertensive drugs, antiplatelets, PPIs or statins and CCyR rate at 6 or 12 months.
Even though few pharmacokinetic interactions are reported between imatinib and some of medications we considered, this does not seem to have an impact on cytogenetic response rate in our cohort. Indeed, our results confirm the well-known safety and efficacy of imatinib also in very elderly CML patients
A new dataset of PCB half-lives in soil: Effect of plant species and organic carbon addition on biodegradation rates in a weathered contaminated soil
Very Elderly Patients with Chronic Phase-Chronic Myeloid Leukemia on Imatinib: No Impact of Concomitant Drugs on Complete Cytogenetic Response
Prevalence of peripheral artery disease by abnormal ankle-brachial index in atrial fibrillation: implications for risk and therapy.
To the Editor:
Nonvalvular atrial fibrillation (NVAF) is the most common sustained arrhythmia encountered in clinical practice and is associated with a 5-fold increased risk for stroke (1).
Moreover, patients with NVAF often suffer from atherosclerotic complications such as acute myocardial infarction (AMI) (2). Peripheral artery disease (PAD) is an established marker of systemic atherosclerosis but its prevalence in NVAF is still unclear. We reasoned that inclusion of ankle-brachial index (ABI), which is an established tool for diagnosis of PAD (3), in the CHA2DS2-VASc (4) score would better define the prevalence of vascular disease.
To address this issue, the Italian Society of Internal Medicine (SIMI) established an Italian registry documenting ABI in NVAF patients.
The Atrial Fibrillation Registry for the ARAPACIS (Ankle-brachial Index Prevalence Assessment: Collaborative Italian Study) study is an independent research project involving all Regional Councils of SIMI. The first objective of the study was to estimate the prevalence of ABI 640.90 in NVAF patients.
Consecutive patients with NVAF referred to internal medicine wards were eligible for the enrollment. Enrollment started in October 2010 and continued until October 30, 2012. Patients were enrolled if they were 18 years or older and had a diagnosis of NVAF, recording during the qualifying admission/consultation or in the preceding 12 months, and if it was possible to obtain the ABI measurement. Exclusion criteria included the following: acquired or congenital valvular AF, active cancer, disease with life expectancy <3 years, hyperthyroidism and pregnancy.
We initially planned to include 3,000 patients. The Data and Safety Monitoring Board (Online Appendix) decided to perform an interim analysis to assess the prevalence of ABI in the enrolled populations\u2014as a higher than expected prevalence of low ABI was detected\u2014and decided to interrupt the patients' enrollment. The sample size was amended as follows: a sample of 2,027 patients leads to the expected prevalence of 21% with a 95% confidence interval width of 3.5% (StataCorp LP, College Station, Texas).
Among the 2,027 NVAF patients included in the study, hypertension was detected in 83%, diabetes mellitus in 23%, dyslipidemia in 39%, metabolic syndrome in 29%, and smoking in 15%. At least 1 atherosclerotic risk factor was detected in 90% of patients.
The NVAF population was at high risk for stroke, with only 18% having a CHA2DS2-VASc score of 0 to 1, while 82% had a risk 652. Despite this, 16% were untreated with any antithrombotic drug, 19% were treated with antiplatelet drugs (APs), and 61% with oral anticoagulants (OAC); 4% of patients were treated with both APs and OAC.
Among the AF population, 428 patients (21%) had ABI 640.90 compared with 1,381 patients, who had an ABI of 0.91 to 1.39 (69%); 204 patients (10%) had ABI 651.40 (Fig. 1). ABI recorded only in 1 leg was excluded from the analysis (n = 14). ABI 640.90 progressively increased from paroxysmal to permanent NVAF (18%, 21%, 24%; p = 0.0315).
Figure 1.
ABI Distribution of Any Category and CHA2DS2-VASc Score Including ABI 640.90
C = congestive heart failure (or left ventricular systolic dysfunction) (Points: 1), H = hypertension (Points: 1), A2 = Age 6575 years (Points: 2), D = diabetes mellitus (Points: 1), S2 = prior stroke or transient ischemic attack or thromboembolism (Points: 2); V = vascular disease (previous acute myocardial infarction, peripheral arterial disease, or aortic plaque) (Points: 1); A = age 65 to 74 years (Points: 1); Sc = sex category (female) (Points: 1). ABI = ankle brachial index.
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NVAF patients with ABI 640.90 were more likely to be hypertensive (88% vs. 82%; p = 0.032), diabetic (34% vs. 20%; p 0.90 (93% vs. 82%; p < 0.0001).
Logistic regression analysis demonstrated that ABI 640.90 was significantly associated with a smoking habit (odds ratio [OR]: 1.99; 95% confidence interval [CI]: 1.48 to 2.66; p < 0.0001), diabetes (OR: 1.93; 95% CI: 1.51 to 2.46; p < 0.0001), age class 65 to 74 years (OR: 2.05; 95% CI: 1.40 to 3.07; p < 0.0001), age class 6575 years (OR: 3.12; 95% CI: 2.16 to 4.61; p < 0.0001), and history of previous transient ischemic attack/stroke (OR: 1.64; 95% CI: 1.20 to 2.24; p = 0.002).
Vascular disease, as assessed by the history elements of CHA2DS2VASc score, was recorded in 17.3% of patients; inclusion of ABI 640.90 in the definition of vascular disease yielded a total prevalence of 33%. A higher prevalence of vascular disease was detected if ABI 640.90 was included in the CHA2DS2VASc score (Fig. 1). CHA2DS2VASc including ABI 640.90 was more associated with previous stroke (43%; OR: 1.85; 95% CI: 1.41 to 2.44; p < 0.0001) compared to CHA2DS2VASc with ABI 0.91 to 1.39 (23%; OR: 1.52; 95% CI: 1.10 to 2.11; p = 0.0117).
To the best of our knowledge, there is no large-scale study that specifically examined the prevalence of ABI 640.90 in NVAF. In our population, 21% had ABI 640.90 indicating that NVAF is often associated with systemic atherosclerosis.
The CHADS2 has been recently refined with the CHA2DS2-VASc score, which includes vascular disease as documented by a history of AMI, symptomatic PAD, or detection of atherosclerotic plaque in the aortic arch (4).
Comparison of vascular prevalence as assessed by CHA2DS2-VASc score and/or ABI 640.90 is of interest to define the potentially positive impact of measuring ABI in the management of NVAF patients. Inclusion of ABI 640.90 in the definition of vascular disease greatly increased the prevalence of vascular disease, which increased from 17.3% (based on history alone) to 33% (based on ABI) in the entire population. If ABI 640.90 was encompassed in the definition of vascular disease of CHA2DS2-VASc score the prevalence of vascular disease increased in every risk class.
Inclusion of ABI 640.90 in the CHA2DS2-VASc score allowed us to better define the risk profile of NVAF patients with an up-grading of the risk score in each CHA2DS2-VASc score category. This may have important therapeutic implications if the new score could be tested prospectively, as a higher number of NVAF patients would potentially be candidates for an anticoagulant treatment by measuring ABI. A prospective study is, therefore, necessary to validate the risk score of this new definition of vascular disease.
In conclusion, this study provides the first evidence that one-fifth of NVAF patients had an ABI 640.90, indicating that it may represent a simple and cheap method to better define the prevalence of vascular disease in NVAF
Prevalence of peripheral artery disease by abnormal ankle-brachial index in atrial fibrillation: Implications for risk and therapy
To the Editor: Nonvalvular atrial fibrillation (NVAF) is the most
common sustained arrhythmia encountered in clinical practice and
is associated with a 5-fold increased risk for stroke (1).
Moreover, patients with NVAF often suffer from atherosclerotic
complications such as acute myocardial infarction (AMI) (2).
Peripheral artery disease (PAD) is an established marker of systemic
atherosclerosis but its prevalence in NVAF is still unclear. We
reasoned that inclusion of ankle-brachial index (ABI), which is an
established tool for diagnosis of PAD (3), in the CHA2DS2-VASc
(4) score would better define the prevalence of vascular disease.
Toaddress this issue, the ItalianSociety of InternalMedicine (SIMI)
established an Italian registry documenting ABI inNVAF patients.
The Atrial Fibrillation Registry for the ARAPACIS (Ankle-
brachial Index Prevalence Assessment: Collaborative Italian Study)
study is an independent research project involving all Regional
Councils of SIMI. The first objective of the study was to estimate
the prevalence of ABI î0.90 in NVAF patients.
Consecutive patients with NVAF referred to internal medicine
wards were eligible for the enrollment. Enrollment started in
October 2010 and continued until October 30, 2012. Patients were
enrolled if they were 18 years or older and had a diagnosis of
NVAF, recording during the qualifying admission/consultation or
in the preceding 12 months, and if it was possible to obtain the
ABI measurement. Exclusion criteria included the following:
acquired or congenital valvular AF, active cancer, disease with life
expectancy <3 years, hyperthyroidism and pregnancy.
We initially planned to include 3,000 patients. The Data and
Safety Monitoring Board (Online Appendix) decided to perform an
interim analysis to assess the prevalence of ABI in the enrolled
populationsdas a higher than expected prevalence of low ABI was
detecteddand decided to interrupt the patientsâ enrollment. The
sample size was amended as follows: a sample of 2,027 patients leads
to the expected prevalence of 21% with a 95% confidence interval
width of 3.5% (StataCorp LP, College Station, Texas).
Among the 2,027 NVAF patients included in the study, hyper-
tension was detected in 83%, diabetes mellitus in 23%, dyslipidemia
in 39%, metabolic syndrome in 29%, and smoking in 15%. At least 1
atherosclerotic risk factor was detected in 90% of patients.
The NVAF population was at high risk for stroke, with only
18% having a CHA2DS2-VASc score of 0 to 1, while 82% had
a risk î2. Despite this, 16% were untreated with any antith-
rombotic drug, 19% were treated with antiplatelet drugs (APs), and
61% with oral anticoagulants (OAC); 4% of patients were treated
with both APs and OAC.
Among the AF population, 428 patients (21%) had ABI î0.90
(69%); 204 patients (10%) had ABI î1.40 (Fig. 1). ABI recorded
only in 1 leg was excluded from the analysis (n ÂŒ 14). ABI î0.90
progressively increased from paroxysmal to permanent NVAF (18%,
tensive (88% vs. 82%; p Œ 0.032), diabetic (34% vs. 20%; p <
0.0001), or smokers (20% vs. 14%; p Œ 0.0008), or to have experi-
enced transient ischemic attack or stroke (17% vs. 10%; p < 0.001).
21%, 24%; p Œ 0.0315).
NVAF patients with ABI î0.90 were more likely to be hyper-
NVAF patients with ABI î0.90 had a higher percentage of
CHA2DS2-VASc score î2 compared with those with ABI >0.90
(93% vs. 82%; p < 0.0001).
significantly associated with a smoking habit (odds ratio [OR]:
1.99; 95% confidence interval [CI]: 1.48 to 2.66; p < 0.0001),
diabetes (OR: 1.93; 95% CI: 1.51 to 2.46; p < 0.0001), age class 65
to 74 years (OR: 2.05; 95% CI: 1.40 to 3.07; p < 0.0001), age
Logistic regression analysis demonstrated that ABI î0.90 was
class î75 years (OR: 3.12; 95% CI: 2.16 to 4.61; p < 0.0001),
and history of previous transient ischemic attack/stroke (OR: 1.64;
95% CI: 1.20 to 2.24; p Œ 0.002).
Vascular disease, as assessed by the history elements of
CHA2DS2VASc score, was recorded in 17.3% of patients; inclu-
sion of ABI î0.90 in the definition of vascular disease yielded
a total prevalence of 33%. A higher prevalence of vascular disease
was detected if ABI î0.90 was included in the CHA2DS2VASc
score (Fig. 1). CHA2DS2VASc including ABI î0.90 was more
associated with previous stroke (43%; OR: 1.85; 95% CI: 1.41 to
2.44; p < 0.0001) compared to CHA2DS2VASc with ABI 0.91 to
1.39 (23%; OR: 1.52; 95% CI: 1.10 to 2.11; p Œ 0.0117).
To the best of our knowledge, there is no large-scale study that
specifically examined the prevalence of ABI î0.90 in NVAF. In
our population, 21% had ABI î0.90 indicating that NVAF is
often associated with systemic atherosclerosis.
The CHADS2 has been recently refined with the CHA2DS2-
VASc score, which includes vascular disease as documented by
a history of AMI, symptomatic PAD, or detection of atheroscle-
rotic plaque in the aortic arch (4).
Comparison of vascular prevalence as assessed by CHA2DS2-
NVAF patients. Inclusion of ABI î0.90 in the definition of
vascular disease greatly increased the prevalence of vascular disease,
which increased from 17.3% (based on history alone) to 33% (based
compared with 1,381 patients, who had an ABI of 0.91 to 1.39
to better define the risk profile ofNVAFpatients with an up-grading
of the risk score in each CHA2DS2-VASc score category. This may
have important therapeutic implications if the new score could be
tested prospectively, as a higher number of NVAF patients would
on ABI) in the entire population. If ABI î0.90 was encompassed
in the definition of vascular disease of CHA2DS2-VASc score the
prevalence of vascular disease increased in every risk class.
Inclusion of ABIî0.90 in theCHA2DS2-VASc score allowed us
VASc score and/or ABI î0.90 is of interest to define the poten-
tially positive impact of measuring ABI in the management of potentially be candidates for an anticoagulant treatment by
measuring ABI. A prospective study is, therefore, necessary to
validate the risk score of this new definition of vascular disease.
In conclusion, this study provides the first evidence that one-fifth
of NVAF patients had an ABI î0.90, indicating that it may
represent a simple and cheap method to better define the prevalence
of vascular disease in NVAF
Frequency of Left Ventricular Hypertrophy in Non-Valvular Atrial Fibrillation
Left ventricular hypertrophy (LVH) is significantly related to adverse clinical outcomes in patients at high risk of cardiovascular events. In patients with atrial fibrillation (AF), data on LVH, that is, prevalence and determinants, are inconsistent mainly because of different definitions and heterogeneity of study populations. We determined echocardiographic-based LVH prevalence and clinical factors independently associated with its development in a prospective cohort of patients with non-valvular (NV) AF. From the "Atrial Fibrillation Registry for Ankle-brachial Index Prevalence Assessment: Collaborative Italian Study" (ARAPACIS) population, 1,184 patients with NVAF (mean age 72 \ub1 11 years; 56% men) with complete data to define LVH were selected. ARAPACIS is a multicenter, observational, prospective, longitudinal on-going study designed to estimate prevalence of peripheral artery disease in patients with NVAF. We found a high prevalence of LVH (52%) in patients with NVAF. Compared to those without LVH, patients with AF with LVH were older and had a higher prevalence of hypertension, diabetes, and previous myocardial infarction (MI). A higher prevalence of ankle-brachial index 640.90 was seen in patients with LVH (22 vs 17%, p = 0.0392). Patients with LVH were at significantly higher thromboembolic risk, with CHA2DS2-VASc 652 seen in 93% of LVH and in 73% of patients without LVH (p <0.05). Women with LVH had a higher prevalence of concentric hypertrophy than men (46% vs 29%, p = 0.0003). Logistic regression analysis demonstrated that female gender (odds ratio [OR] 2.80, p <0.0001), age (OR 1.03 per year, p <0.001), hypertension (OR 2.30, p <0.001), diabetes (OR 1.62, p = 0.004), and previous MI (OR 1.96, p = 0.001) were independently associated with LVH. In conclusion, patients with NVAF have a high prevalence of LVH, which is related to female gender, older age, hypertension, and previous MI. These patients are at high thromboembolic risk and deserve a holistic approach to cardiovascular prevention