 Outcome
events in patients with claudication: A 15-year study in 2777 patients
Reference: J Vasc Surg
2001;33:251-8
Objective: The purpose
of this study was to delineate the natural history of claudication and
determine risk factors for death.
Methods: We reviewed
the key outcomes (death, revascularization, amputation) in 2777 male patients
with claudication identified over 15 years at a Veterans Administration
hospital with both clinical and noninvasive criteria. Patients with rest
pain or ulcers were excluded. Data were analyzed with life-table and Cox
hazard models.
Results: The mean follow-up
was 47 months. The cohort exhibited a mortality rate of 12% per year, which
was significantly (P < .05) more than the age-adjusted US male population.
Among the deaths in which the cause was known, 66% were due to heart disease.
We examined several baseline risk factors in a multivariate Cox model.
Four were significant (P < .01) independent predictors of death: older
age (relative risk [RR] = 1.3 per decade), lower ankle-brachial index (RR
= 1.2 for 0.2 change), diabetes requiring medication (RR = 1.4), and stroke
(RR = 1.4). The model can be used to estimate the mortality rate for specific
patients. Surprisingly, a history of angina and myocardial infarction was
not a significant predictor. Major and minor amputations had a 10-year
cumulative rate less than 10%. Revascularization procedures occurred with
a 10-year cumulative rate of 18%.
Conclusions: We found
a high mortality rate in this large cohort and four independent risk factors
that have a large impact on survival. Risk stratification with our model
may be useful in determining an overall therapeutic plan for claudicants.
A history of angina and myocardial infarction was not a useful predictor
of death, suggesting that many patients in our cohort presented with claudication
before having coronary artery symptoms. Our data also indicate that claudicants
have a low risk of major amputation at 10-year follow-up.
NOVEL
PLATELET INHIBITORS.
Reference: Annu Rev
Med 2001;52:161-184
Platelet-inhibitory
drugs are of proven benefit
to individuals who suffer from atherosclerotic
cardiovascular disease. Despite substantial effort to identify more potent
platelet-inhibitory agents, aspirin, an irreversible inhibitor of platelet
cyclooxygenase activity, remains the standard against which other drugs
are judged. Drugs that appear to be at least as efficacious as aspirin
in specific clinical settings include the thienopyridines ticlopidine and
clopidogrel, specific inhibitors of ADP-stimulated platelet function, and
the phosphodiesterase 3 inhibitor cilostazol. Ligand binding to the platelet
integrin alphaIIbbeta3 (GPIIb-IIIa), a prerequisite for platelet thrombus
formation, has been a prominent target for drug development. Currently,
three types of alphaIIbbeta3 antagonists are available: the monoclonal
antibody Fab fragment abciximab, cyclic peptides based on the Arg-Gly-Asp
(RGD) or related amino acid motifs, and RGD-based peptidomimetics. The
efficacy of each type of alphaIIb -beta3 antagonist in the setting of acute
coronary artery disease has been confirmed in multicenter clinical trials.
Decrease
in carotid intima media thickness after 1 year of cilostazol treatment
in patients with type 2 diabetes mellitus.
Reference: Diabetes Res Clin Pract 2001;52(1):45-53
A multicenter exploratory study at three university hospitals was performed
to evaluate the effect
of oral cilostazol on intima media thickness (IMT) in diabetic patients.
A total of 141 patients was
recruited in this study and randomized into a cilostazol group and a placebo
(control) group. One
hundred and twenty patients completed the study (i.e. 60 on cilostazol
and 60 on placebo).
Biochemical profiles and the IMT of the common carotid artery (CCA) determined
by
high-resolution B-mode ultrasonography were measured at 0, 6, and 12 months
after the oral
administration of 100-200 mg of cilostazol or placebo (i.e. two or four
times daily for 12 months).
Clinical and biochemical characteristics, the treatment modality, and microvascular
diabetic
complications after randomization were not significantly different between
the two groups after the
study. In the cilostazol treatment group, left CCA average IMT significantly
decreased from
0.94+/-0.03 to 0.91+/-0.02 mm at 6 months (P<0.05), and thereafter increased
to 0.92+/-0.01 mm
(P>0.05) at 12 months, whereas in the control group, it increased from
0.92+/-0.03 to 0.93+/-0.01
mm at 6 months (P>0.05), and to 0.94+/-0.01 mm at 12 months (P>0.05). As
for the right CCA
average IMT, it decreased from 0.83+/-0.03 to 0.82+/-0.01 mm at 6 months
(P<0.05), and to
0.81+/-0.01 mm at 12 months (P<0.05) in the cilostazol group, whereas
it increased from
0.87+/-0.03 to 0.89+/-0.01 mm at 6 months (P<0.05), and to 0.90+/-0.01
mm at 12 months (P<0.05)
in the control group (P<0.05). After correction for risk factors such
as blood pressure, smoking, and
lipid profiles, there were significant changes in left and right CCA average
IMT for both groups
(P<0.05). Left and right CCA average IMT was significantly different
between the two groups
(P<0.05). After making statistical corrections for blood pressure, smoking,
and lipid profiles, the
differences between these two groups remained significant (P<0.05).
Meanwhile, there were no
differences between the groups in the change of risk factors such as BMI,
blood pressure, blood
sugar, HbA(1c), and lipid profiles. Generally, cilostazol was well tolerated
and the most common
side effect in the cilostazol group was headache (12/60), mostly early
in the treatment regimen. The
results suggest that oral cilostazol may be helpful in the treatment of
atherosclerosis in type 2
diabetic patients, although conventional cardiovascular risk factors remained
unmodified.
Multistate
utilization, processes, and outcomes of carotid endarterectomy.
Reference: J Vasc Surg 2001;33(2Pt 1):227-235.
OBJECTIVES: The purpose of this study was to describe variation in utilization,
care processes,
and outcomes for carotid endarterectomy (CEA) procedures in 10 states.
METHODS: We
reviewed the medical records of Medicare patients who underwent 10,561
CEA procedures
between June 1, 1995, and May 31, 1996, in 10 different states to determine
indications, care
processes, and outcomes. This study also included medical record review
of hospital readmissions
within 30 days of the procedure and identification of out-of-hospital deaths
from the Medicare
beneficiary files. RESULTS: Utilization rates of CEA varied from 25.7 to
38.4 procedures per
10,000 Medicare beneficiaries among states. The overall combined event
rate (30-day stroke or
mortality) was 5.2% for primary CEA alone (n = 9945). The mortality rate
was 1.5%, and the
nonfatal stroke rate was 3.7%. Combined event rates (CEA alone) by surgical
indication were
7.7% for stroke (n = 1037), 7.4% for transient ischemic attack (n = 1304),
5.3% for nonspecific
symptoms (n = 3713), and 3.7% for asymptomatic patients (n = 3891). The
combined event rates
(CEA alone) among states ranged from 4.1% to 7.7% with the event rates
in asymptomatic
patients ranging from 2.3% to 6.7%. In a multivariate analysis (correcting
for indication), the use of
preoperative antiplatelet agents (odds ratio [OR], 0.70), intraoperative
heparin (OR, 0.49), and
patch angioplasty (OR, 0.73) was significantly associated with lower combined
event rates. There
were significant differences among states in the use of preoperative antiplatelet
therapy (range,
56%-70%) and patch angioplasty (range, 11%-49%). Combined event rates for
repeat procedures
(n = 380) and CEA combined with coronary artery bypass grafting (n = 236)
were 6.3% and
17.4%, respectively. CONCLUSIONS: The striking variation among states suggests
that there is
room for improvement in the utilization, care processes, and outcomes of
CEA. All surgeons
performing CEA should participate in outcome assessment and adopt protocols
that include the
routine administration of antiplatelet agents preoperatively, the use of
heparin intraoperatively, and
patch angioplasty of the endarterectomy site.
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Volume
4, Number 3: March 2001
