Diagnosis of Pulmonary Embolism by Multidetector CT
Source: Eighini M, et al. Lancet. 2008;371:1343-1352.
Because the consequence of missed pulmonary embolism (PEM) is so grave, it is essential to continue our evolution of tools which maximize diagnostic sensitivity, offer clinical expedience, and minimize risk for the patient. Recently, the combination of clinical probability assessment (CPA) with d-dimer, venous compression ultrasound (v-US), and helical CT has enjoyed advocacy, but multislice CT (MSCT) provides even better vascular visualization down to the level of segmental and subsegmental vessels.
Righini, et al compared a strategy of d-dimer plus either MSCT or d-dimer plus MSCT and v-US in a study population (n = 1,819) all of whom had undergone clinical probability assessment because of suspicion of PEM.
The frequency of PEM confirmation was the same in both groups: 20.6%. During a 3-month follow-up of persons who had screened negative for PE, the incidence of documented episodes of thromboembolism was 0.3% in both groups.
These data suggest that the combination of d-dimer with MSCT is as effective as a diagnostic plan incorporating v-US to both confirm the diagnosis of PEM and effectively exclude those without it.
The Impact of Medicare Part B on Medication Nonadherence Among Seniors
Source: Madden JM, et al. JAMA. 2008;299(16):1922-1928.
One of the goals of the Medicare Prescription Drug Improvement and Modernization Act of 2003 (MPD) was to provide more universal coverage for essential medications for senior citizens and the disabled. Because of the expense of medications and consistency of polypharmacy among seniors, medication behaviors such as dose-skipping, dose reduction, or frank medication omission occur all too often.
Prior to MPD as many as 38% of Medicare beneficiaries did not have a source of prescription coverage, but that number has now been reduced to about 10%. Did the MPD reduce cost-related medication nonadherence?
To determine the answer, a representative sample of Medicare enrollees (n = 15,700) responded to questions addressing cost-related nonadherence such as "did you skip doses/take smaller doses of medicine to make it last longer." Because behaviors such as skimping on food, heat, or other basic needs to afford medicine has also been commonly seen in the past, these behaviors were also addressed on questionnaires.
Since MPD, spending less on basic needs decreased from 10.6% to 7.6%. There was also a 15% reduction in cost-related nonadherence overall. Unfortunately, the least healthy individuals (rated as fair to poor health) did not demonstrate the same reductions.
MPD has benefitted Medicare beneficiaries overall. The sickest beneficiaries still experience unabated cost-related nonadherence behaviors.
Liberty, Justice, and Hypertension Treatment for ALL
Source: Beckett NS, et al. N Engl J Med. 2008;358:1887-1898.
The benefits of treatment of hypertension (HTN) include meaningful reductions in stroke, MI, CHF, and overall mortality. Typically, HTN treatment trials enroll adults from middle-aged and early geriatric groups, without a large representation of advanced seniors (> age 80). The gap in knowledge about advanced seniors has been closed by HYVET (Hypertension in the Very Elderly Trial).
A large population (n=3,845) of advanced senior subjects (mean age =83.6) was randomized to indapamide or placebo for 2 years. If BP was not controlled on indapamide monotherapy, perindopril was added (BP target = 150/80). The primary endpoint of the trial was fatal or nonfatal stroke.
Indapamide treatment reduced the primary endpoint by 30%. Additionally, treatment provided a 21% reduction in all-cause mortality and 64% reduction in heart failure (all statistically significant). Differences between placebo and active treatment became visible within as little as 12 months time. Remarkably, the frequency of serious adverse events was lower in the active treatment group than the placebo group. Even change in potassium, a well recognized adverse effect of thiazide diuretics, was not significantly more common in the indapamide treatment group than in the placebo group.
These data support that concept that advanced age should not be a limiting factor in the decision to treat hypertension.
The Carotids Blow the Whistle on Crimes in the Heart
Source: Pickett CA, et al. Lancet. 2008;371:1587-1594.
Vasculopathy knows no compartmentalization. Clinicians expect that patients with peripheral arterial disease will also commonly have comorbid coronary or cerebrovascular disease, even though it may be silent. The last decade has confirmed that the endothelial dysfunction of erectile dysfunction is a harbinger of coronary artery disease. Carotid intima-media thickness is a commonly employed surrogate in hypertension and dyslipidemia trials. What implications then, might a clinician make about an ausculted carotid bruit?
Pickett et al performed a meta-analysis of 17,295 patients in 22 reports which included information about persons with/without carotid bruit and cardiovascular outcomes during followup (mean 4 years).
The odds ratio for MI was more than double for subjects with carotid bruit than without, and even greater for CV death. This meta analysis supports the concept that vascular disease in the carotids, as manifest by carotid bruit, is corroboration of meaningful vascular disease in other tissue compartments, specifically the coronary bed.
National guidelines recognize the presence of diabetes or peripheral arterial disease as a cardiac disease equivalent; ie, associated with > 20% risk of cardiac event within 10 years. These data indicate a similar or greater risk of coronary events in patients with carotid bruit. Based on these observations, clinicians might use the presence of a carotid bruit to help support aggressive risk factor modulation.
Vitamin Shmitamin
Source: Albert CM, et al. JAMA. 2008;299:2086-2087.
Everything about the homocysteine hypothesis looked so good: a strong association of elevations with vascular disease, prototypic premature vascular disease in youth associated with disordered homocysteine and vitamin B12 metabolism, prompt reductions of homocysteine with folic acid … UNTIL interventional trials called a screeching halt to homocysteine enthusiasm. Despite consistent failed trials of B vitamin intervention, because women have been underrepresented in the interventional trials to date (and might, according to the observational data, benefit more than men), it was worth consideration that a gender-specific trial was in order.
Female health professionals (n=5,442) aged 42 or greater who were considered high risk for CV disease (on the basis of 3 or more coronary risk factors) were randomized to combination folic acid/B12/B6 (VIT) or placebo for 7.3 years. The primary outcome was a composite of MI, stroke, CVD mortality, and coronary revascularization.
Neither the primary endpoint nor any individual endpoint was advantageously impacted by VIT, despite substantial homocysteine lowering. Because health professional women have lesser prevalence of vitamin deficiency than the general population, it is possible that had a less vitamin-replete group been studied, the impact of B vitamins may have been more dramatic. In any case, these data are consistent with the growing body of evidence that B vitamin supplementation does not impact cardiovascular disease.
Fracture Risk, Diabetes, and Rosiglitazone
Source: Kahn SE, et al. Diabetes Care. 2008;31:845-851.
Clinicians probably automatically insert the word "osteoporosis" whenever the words "fracture" and "woman" appear in the same sentence. In the case of diabetes, however, other factors are at play. Diabetic women are at increased risk of fracture in the absence of osteoporosis, although it remains to be discerned why this fracture risk occurs; there has been some suggestion that diabetics, perhaps due to neuropathy, are at greater risk of falls, resulting in more fracture.
Some earlier clinical trials have noted a bone mineral density decrease in diabetic women treated with thiazolidinediones (TZD), providing rationale to examine this issue in the ADOPT trial, a large study (n = 4,351) comparing TZD (rosiglitazone), metformin, and glyburide monotherapy in men and women with newly diagnosed type 2 diabetes.
Over a 4 year treatment period, when compared with metformin or glyburide, rosiglitazone was associated with an increased risk of fracture in women: 1.8 greater relative risk than metformin, and more than a doubling of risk compared to sulfonylurea. Increased risk is discernible as early as 1 year after treatment, but (at least in this data) was not associated with increased falls, and is seen in younger, premenopausal women as well. Although the mechanism by which thiazolidinediones increase fracture risk is unclear, this observation should prompt greater vigilance by clinicians, and should be factored into the decision process of the risk/benefit ratio of oral antidiabetic agents.
Diagnosis of Pulmonary Embolism by Multidetector CT; The Impact of Medicare Part B on Medication Nonadherence Among Seniors; Liberty, Justice, and Hypertension Treatment for ALL; The Carotids Blow the Whistle on Crimes in the Heart; Vitamin Shmitamin; Fracture Risk, Diabetes, and RosiglitazoneYou have reached your article limit for the month. Subscribe now to access this article plus other member-only content.
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