Suitability of bupropion SR for nicotine-dependent smokers: problems in a practice setting

BACKGROUND: Bupropion SR (Zyban) has been shown in randomized controlled trials to be an efficacious pharmacological aid for smoking cessation; however, recent reports have raised serious concerns about the breadth of its applicability without complications or contraindications. METHODS: We examined this issue in a well-documented medical population, i.e. veterans volunteering to participate in a smoking cessation treatment research program involving the use of bupropion SR. RESULTS: Overall, 22% of the 78 subjects who met the study criteria were appropriate for and completed the course of medication. CONCLUSIONS: Thus, bupropion SR in nicotine-dependent veterans may not be broadly applicable when conservative prescribing guidelines are carefully followed.     

Design and acceptability of patient-oriented computerized diabetes care reminders for use at the point of care

Despite the widespread availability of guidelines for caring for patients with diabetes and decades of research on computerized reminder systems, large gaps in quality remain in diabetes care remain and computerized reminder systems are rarely used for patients with diabetes. We set out to develop and test the feasibility of a system that would overcome many of the barriers preventing the widespread use of point-of-care computerized reminders to improve diabetes care. Five primary care physicians and 32 patients with type 2 diabetes pilot tested the system. We set out to design and measure the preliminary acceptability of patient-oriented point of care computerized diabetes care reminders. The main findings of our study were that (1) the reports were well accepted by both patients and providers and (2) survey and audiotape data suggest that they may be helpful at improving the quality of outpatient care for patients with diabetes.     

Chronic disease self-management and adherence to HIV medications

Although it is widely recognized that potent antiretroviral therapies have transformed HIV from an acute to a chronic illness, it is less often recognized that with this change, a different model of care is appropriate. People living with chronic HIV must function independently, taking personal long-term, day-to-day responsibility for care. The role of doctors and the healthcare system is to help them do this. The authors present a conceptual framework for the self-management of chronic HIV disease and discuss the components of an HIV self-management program. The ability to take antiretroviral medications well and consistently is a key part of self-management but should be nested within an array of important skills, including symptom-management skills, goal setting and planning, communication, and accessing information and resources.     

Ventricular rate stabilization for the prevention of pause dependent ventricular tachyarrhythmias: results from a prospective study in 309 ICD recipients

Reviews of stored electrograms from ICDs revealed a 5-30% incidence of short-long-short intervals preceding the onset of recurrent ventricular tachyarrhythmias. Rate stabilization by dedicated antibradycardia pacing algorithms has, therefore, been suggested to prevent onset of pause dependent tachyarrhythmias. However, the clinical efficacy of this approach has not been studied systematically. In a prospective multicenter crossover study, patients were randomized to activation or deactivation of an implemented ventricular rate stabilization algorithm (VRS) after first implant of a dual chamber ICD. After 3 months, all patients were crossed over to the alternate programming. The rate of appropriate spontaneous VA episodes was compared between VRS On and VRS Off. Stored electrograms were reviewed for evaluation of the mode of onset of tachyarrhythmias. Overall efficacy analysis was based on 309 patients enrolled in the study. Forty percent (124/309) of the patients experienced 4,973 VA episodes. Based on an intention-to-treat analysis, VRS Off and On arrhythmia incidence was 10.2 and 6.6 normalized to 3 months, respectively (risk reduction 35%; P = 0.18) On an on-treatment basis, a reduction from 9.0 episodes to 8.1 episodes (10% risk reduction, P = 0.24) was seen. In an extended Cox model adjusting for confounding variables, the relative risk for recurrent episodes was 0.92 during VRS On compared to Off (95% CI: 0.58-1.48; P = 0.74). During VRS Off, pause dependent onset was documented in only 36 (8%) of 427 visually analyzed episodes. There was no significant reduction in the incidence of recurrent ventricular tachyarrhythmias with VRS On compared to the Off programming in this prospective study.     

Acute myocardial infarction as a complication of clonidine withdrawal

Abrupt withdrawal from clonidine therapy is a well-known cause of hyperadrenergic symptoms, but reports of acute myocardial infarction are extremely rare. We present the case of an 86-year-old woman who developed severe hypertension and a myocardial infarction 36 h after terminating her therapy of clonidine, 0.4 mg/day. Symptoms quickly responded to the administration of labetolol and diazepam. Subsequent cardiac catheterization showed no evidence of coronary occlusion, suggesting that excessive myocardial oxygen demand was responsible for the infarction.     

Quality improvement for pressure ulcer care in the nursing home setting: the Northeast Pressure Ulcer Project

OBJECTIVES: The objectives of this study were to evaluate the impact of a collaborative model of quality improvement in nursing homes on processes of care for the prevention and treatment of pressure ulcers. STUDY DESIGN: The study design was experimental. SETTING: We studied 29 nursing homes in New Jersey, Pennsylvania, and Rhode Island. PARTICIPANTS: Participants consisted of pressure ulcer quality improvement teams in 29 nursing homes. INTERVENTION: Quality improvement teams attended a series of workshops to review clinical guidelines and quality improvement principles and to share best practices, and worked one-on-one with mentors to implement quality improvement techniques and to collect data independently. MEASUREMENTS: We calculated process measures based on the Agency for Healthcare Research and Quality (AHRQ) guidelines. Process measures addressed each facility's processes of care for the prevention and treatment of pressure ulcers at baseline and after 12 months of intervention. Prevention measures focused on recent admissions and high-risk residents; treatment measures focused on patients newly diagnosed with pressure ulcers and all patients with pressure ulcers. RESULTS: Overall, 6 of 8 prevention process measures improved significantly, with percent difference between baseline and follow up ranging from 11.6% to 24.5%. Three of 4 treatment process measures improved significantly, with 5.0%, 8.9%, and 25.9% difference between baseline and follow up. For each process measure, between 5 and 12 facilities demonstrated significant improvement between baseline and follow up, and only 2 or fewer declined for each process measure. CONCLUSION: Improvement in processes of care after the use of a structured collaborative quality improvement approach is possible in the nursing home setting.     

Cardiovascular effects of methylphenidate in humans are associated with increases of dopamine in brain and of epinephrine in plasma

Rationale. The cardiovascular effects of psychostimulant drugs (methylphenidate, amphetamine, cocaine) have been mostly associated with their noradrenergic effects. However, there is some evidence that dopaminergic effects are involved in the cardiovascular actions of these drugs. Here, we evaluated this association in humans. Methods. Positron emission tomography (PET) and [¹¹C]raclopride, a dopamine (DA) D2 receptor radioligand that competes with endogenous DA for occupancy of the D2 receptors, were used to measure changes in brain DA after different doses of intravenous methylphenidate in 14 healthy subjects. Cardiovascular (heart rate and blood pressure) and catecholamine (plasma epinephrine and norepineprhine) responses were determined in parallel to assess their relationships to methylphenidate-induced changes in brain DA. Results. Methylphenidate administration significantly increased heart rate, systolic and diastolic blood pressures and epinephrine concentration in plasma. The increases in blood pressure were significantly correlated with methylphenidate-induced increases of DA in striatum (r>0.78, P<0.001) and of plasma epinephrine levels (r>0.82, P<0.0005). In turn methylphenidate-induced DA increases in striatum were correlated with increases of epinephrine in plasma (r=0.85, P<0.0001). Subjects in whom methylphenidate did not increase DA had no change in blood pressure or in plasma epinephrine concentration. Discussion. These results are consistent with the hypothesis that methylphenidate-induced increases in blood pressure are in part due to its central dopaminergic effects. They also suggest that methylphenidate's pressor effects may be in part mediated by DA-induced increases in peripheral epinephrine. Electronic Publication     

Neural processing of gravito-inertial cues in humans. II. Influence of the semicircular canals during eccentric rotation

All linear accelerometers, including the otolith organs, respond equivalently to gravity and linear acceleration. To investigate how the nervous system resolves this ambiguity, we measured perceived roll tilt and reflexive eye movements in humans in the dark using two different centrifugation motion paradigms (fixed radius and variable radius) combined with two different subject orientations (facing-motion and back-to-motion). In the fixed radius trials, the radius at which the subject was seated was held constant while the rotation speed was changed to yield changes in the centrifugal force. In variable radius trials, the rotation speed was held constant while the radius was varied to yield a centrifugal force that nearly duplicated that measured during the fixed radius condition. The total gravito-inertial force (GIF) measured by the otolith organs was nearly identical in the two paradigms; the primary difference was the presence (fixed radius) or absence (variable radius) of yaw rotational cues. We found that the yaw rotational cues had a large statistically significant effect on the time course of perceived tilt, demonstrating that yaw rotational cues contribute substantially to the neural processing of roll tilt. We also found that the orientation of the subject relative to the centripetal acceleration had a dramatic influence on the eye movements measured during fixed radius centrifugation. Specifically, the horizontal vestibuloocular reflex (VOR) measured in our human subjects was always greater when the subject faced the direction of motion than when the subjects had their backs toward the motion during fixed radius rotation. This difference was consistent with the presence of a horizontal translational VOR response induced by the centripetal acceleration. Most importantly, by comparing the perceptual tilt responses to the eye movement responses, we found that the translational VOR component decayed as the subjective tilt indication aligned with the tilt of the GIF. This was true for both the fixed radius and variable radius conditions even though the time course of the responses was significantly different for these two conditions. These findings are consistent with the hypothesis that the nervous system resolves the ambiguous measurements of GIF into neural estimates of gravity and linear acceleration. More generally, these findings are consistent with the hypothesis that the nervous system uses internal models to process and interpret sensory motor cues.