5-Azacytidine Transiently Restores Dysregulated Erythroid Differentiation Gene Expression in TET2-Deficient Erythroleukemia Cells

DNA methyltransferase inhibitors (DNMTI) like 5-Azacytidine (5-Aza) are the only disease-modifying drugs approved for the treatment of higher-risk myelodysplastic syndromes (MDS), however less than 50% of patients respond, and there are no predictors of response with clinical utility. Somatic mutations in the DNA methylation regulating gene tet-methylcytosine dioxygenase 2 (TET2) are associated with response to DNMTIs, however the mechanisms responsible for this association remain unknown. Using bisulfite padlock probes, mRNA sequencing, and hydroxymethylcytosine pull-down sequencing at several time points throughout 5-Aza treatment, we show that TET2 loss particularly influences DNA methylation (5mC) and hydroxymethylation (5hmC) patterns at erythroid gene enhancers and is associated with downregulation of erythroid gene expression in the human erythroleukemia cell line TF-1. 5-Aza disproportionately induces expression of these down-regulated genes in TET2KO cells and this effect is related to dynamic 5mC changes at erythroid gene enhancers after 5-Aza exposure. We identified differences in remethylation kinetics after 5-Aza exposure for several types of genomic regulatory elements, with distal enhancers exhibiting longer-lasting 5mC changes than other regions. This work highlights the role of 5mC and 5hmC dynamics at distal enhancers in regulating the expression of differentiation-associated gene signatures, and sheds light on how 5-Aza may be more effective in patients harboring TET2 mutations. IMPLICATIONS: TET2 loss in erythroleukemia cells induces hypermethylation and impaired expression of erythroid differentiation genes which can be specifically counteracted by 5-Azacytidine, providing a potential mechanism for the increased efficacy of 5-Aza in TET2-mutant patients with MDS. VISUAL OVERVIEW: http://mcr.aacrjournals.org/content/molcanres/19/3/451/F1.large.jpg.

Adverse Effects of Cholinesterase Inhibitors in Dementia, According to the Pharmacovigilance Databases of the United-States and Canada

This survey analyzes two national pharmacovigilance databases in order to determine the major adverse reactions observed with the use of cholinesterase inhibitors in dementia. We conducted a statistical analysis of the Food and Drug Administration Adverse Event Reporting System (FAERS) and the Canada Vigilance Adverse Reaction Database (CVARD) concerning the side effects of cholinesterase inhibitors. The statistics calculated for each adverse event were the frequency and the reporting odds ratios (ROR). A total of 9877 and 2247 reports were extracted from the FAERS and CVARD databases, respectively. A disproportionately higher frequency of reports of death as an adverse event for rivastigmine, compared to the other acetylcholinesterase inhibiting drugs, was observed in both the FAERS (ROR = 3.42; CI95% = 2.94-3.98; P<0.0001) and CVARD (ROR = 3.67; CI95% = 1.92-7.00; P = 0.001) databases. While cholinesterase inhibitors remain to be an important therapeutic tool against Alzheimer's disease, the disproportionate prevalence of fatal outcomes with rivastigmine compared with alternatives should be taken into consideration.

The observation unit: a new interface between inpatient and outpatient care

PURPOSE

Observation units for patients who present to emergency departments with chest pain have become common. We describe our 3-year experience with a multipurpose observation unit in which chest pain accounts for only a minority of patients' presenting clinical syndromes.

SUBJECTS AND METHODS

We analyzed the effects of a 12-bed observation unit on inpatient admissions for common clinical syndromes, as well as its overall effects on inpatient medical admissions during its first 3 years of operation (1996 to 1998) compared with the 3 years preceding its creation (1993 to 1995).

RESULTS

Among 7,507 patients admitted to the observation unit in 1996 to 1998, 6,334 (85%) were discharged home within 23 hours. Total inpatient medical admissions fell by a similar number (n = 5,366) during the 3 years of operation of the observation unit when compared with the 3 preceding years (39,569 admissions in 1996 to1998 versus 44,935 in 1993 to 1995). Analysis of local area trends suggested that the use of the observation unit contributed to reduced hospital admissions, rather than vice versa.

CONCLUSION

Observation units can serve patients with diverse clinical syndromes and may reduce inpatient admissions. This novel "point of care" deserves further evaluation.

Teaching residents evidence-based medicine skills: a controlled trial of effectiveness and assessment of durability

OBJECTIVES

To measure the effectiveness of an educational intervention designed to teach residents four essential evidence-based medicine (EBM) skills: question formulation, literature searching, understanding quantitative outcomes, and critical appraisal.

DESIGN

Firm-based, controlled trial.

SETTING

Urban public hospital.

PARTICIPANTS

Fifty-five first-year internal medicine residents: 18 in the experimental group and 37 in the control group.

INTERVENTION

An EBM course, taught 2 hours per week for 7 consecutive weeks by senior faculty and chief residents focusing on the four essential EBM skills.

MEASUREMENTS AND MAIN RESULTS

The main outcome measure was performance on an EBM skills test that was administered four times over 11 months: at baseline and at three time points postcourse. Postcourse test 1 assessed the effectiveness of the intervention in the experimental group (primary outcome]; postcourse test 2 assessed the control group after it crossed over to receive the intervention; and postcourse test 3 assessed durability. Baseline EBM skills were similar in the two groups. After receiving the EBM course, the experimental group achieved significantly higher postcourse test scores (adjusted mean difference, 21%; 95% confidence interval, 13% to 28%; P < .001). Postcourse improvements were noted in three of the four EBM skill domains (formulating questions, searching, and quantitative understanding [P < .005 for all], but not in critical appraisal skills [P = .4]). After crossing over to receive the educational intervention, the control group achieved similar improvements. Both groups sustained these improvements over 6 to 9 months of follow-up.

CONCLUSIONS

A brief structured educational intervention produced substantial and durable improvements in residents' cognitive and technical EBM skills.

Part II. Evidence-based medicine: a passing fancy or the future of primary care?

Reliable experimental evidence provides a firm scientific foundation for only a minority of the clinical decisions primary care practitioners must make each day. Thus clinicians' experience and judgment must complement and supplement their knowledge of published research studies. This presents a dynamic and difficult challenge to the practitioner--one that is magnified when combined with the never ending influx of medical information, with patients' and physicians' uneasiness with clinical uncertainty, and with new external pressures to standardize care. With these factors in mind, this article will review evidence-based medicine, a process and philosophy for the practice and teaching of clinical medicine that has sparked much controversy in recent years. Clinical scenarios commonly encountered in adult primary care--acute low back pain, hypertension, and screening for vascular disease--illustrate some strengths and limitations of evidence-based medicine.

Primary care for the medically underserved: challenges and opportunities

The medically underserved present unique challenges to primary care practitioners. Sociocultural and financial barriers of the underserved impede access to necessary care; the prevalence and severity of diseases in the underserved population vary from those of the general population; the institution of preventive-care measures can be especially problematic; and the doctor-patient relationship is uncommonly complex. This article reviews current thinking about the causes of unequal health, the effects of unequal health care, and the special opportunities for disease prevention among the socioeconomically disadvantaged people in the US. Sensitivity to these and other issues can enhance primary care practitioners' efforts to improve care of the underserved now, pending future political consensus about universal health insurance.

Enhancing mammography use in the inner city. A randomized trial of intensive case management

BACKGROUND

Breast cancer screening with mammography is an effective intervention for women aged 50 to 75 years but it is underused, especially by the urban poor.

OBJECTIVE

To improve mammography completion rates for urban women aged 52 to 77 years who had not had a mammogram in at least 2 years.

METHODS

We conducted a randomized controlled trial of a case management intervention by culturally sensitive community health educators vs usual care in 6 primary care practices supported by a computerized clinical information system.

RESULTS

Women in the intervention group were nearly 3 times as likely to receive a mammogram (relative risk, 2.87; 95% confidence interval, 1.75-4.73). The benefit persisted when analyzed by age; race, and prior screening behavior. This intervention was practice based, not dependent on visits, and enhanced the efficacy of an already successful computerized preventive care information system.

CONCLUSIONS

Personalized education and case management are successful in enhancing compliance with breast cancer screening among historically noncompliant vulnerable urban women. This intervention, when combined with a preventive care information system, has the potential to achieve Healthy People 2000 objectives for breast cancer screening.

New method to predict patients' intravenous heparin dose requirements

OBJECTIVE

To predict intravenous heparin dose requirements of patients treated for thromboembolic disorders.

DESIGN

A retrospective cohort study in which we used simple linear regression to predict patients' effective maintenance dose (EMD) of heparin (units/kg/hour needed to achieve and maintain APTT therapeutic range) from patients' "heparin responsiveness" (the APTT increase after the initial 6 hours of heparin treatment per units/kg/hour received).

SETTING/PATIENTS

The model was derived from 46 patients treated at one hospital (Hospital A) and then tested in 42 patients treated at another hospital (Hospital B).

MEASUREMENTS AND MAIN RESULTS

Among Hospital A patients, there was a strong linear correlation (r = -.880; p < .001) between EMD (mean 16.02 units/kg/hour; 95% CI 14.9, 17.15) and "heparin responsiveness" (HR): EMD = 25.651 - [95.118 x HR]. This model accurately predicted Hospital B patients' EMD: 97% (37/38) fell within the model's 95% prediction interval; the mean absolute difference between predicted and actual EMD was 1.73 units/kg/hour (95% CI 1.39, 2.08); and only 16% of patients had EMD's more than 3 units/kg/hour different from that predicted by the regression model. The model's accuracy was comparable to that of our gold standard, the weight-based heparin dosing nomogram.

CONCLUSION

The infusion dose of intravenous heparin effective for an individual patient can be predicted accurately from the patient's body weight and APTT response to the initial 6 hours of treatment. Especially in hospitals where validated heparin dosing nomograms are not used, clinicians may find this simple technique useful in achieving timely therapeutic anticoagulation.

Promoting inpatient directives about life-sustaining treatments in a community hospital. Results of a 3-year time-series intervention trial

BACKGROUND

Hospitalization presents an opportunity for physicians to discuss advance directives with patients and to encourage completion of health care proxies.

OBJECTIVE

To prospectively promote discussion and documentation of treatment-specific directives about life-sustaining interventions (cardiopulmonary resuscitation, admission to critical care units, mechanical ventilation, electrical cardioversion, and vasopressor therapy) among unselected medical inpatients in a community teaching hospital.

METHODS

We conducted a time-series intervention trial from January 1, 1991, through June 30 1993, divided into three phases. During the education phase, we provided reminders, education, and feedback to attending physicians; during the intervention phase, we promoted a new documentation form for directives to be used by attending physicians; during the control phase, no interventions occurred. We studied consecutive patients (N = 1780) admitted to the hospital acute medical service in each of the following 10 periods: three in the education phase (n = 598), three in the intervention phase (n = 826), and four in the control phase (n = 356). The primary outcome measures were the frequency and content of directives documented by attending physicians in their patients' hospital charts. Secondary outcome measures included physicians' and patients' attitudes about directives, surveyed repeatedly.

RESULTS

The proportion of inpatients with directives increased significantly during the intervention phase (62.5% vs 23.6% during the education phase and 25.3% during the control period, P < .001, Pearson chi 2 test). During the final intervention phase, 227 (83.2%) of 273 inpatients had directives documented in the hospital chart. Increases in clinically important ("impact") directives usually involved intensive care, not do-not-resuscitate status. Overall, 366 (86.7%) of 422 physician-attested directives agreed with the treatment preferences of interviewed patients (kappa ranges, 0.53 to 0.79). Physicians' attitudes about and interest in directives improved.

CONCLUSIONS

Institutional interventions can facilitate attending physicians' documentation of treatment-specific directives about life-sustaining care for most medical inpatients. More research is needed to confirm the effect of these efforts on quality and cost of hospital care, patients' autonomy, and their eventual execution of durable directives and proxies.

Promoting completion of health care proxies following hospitalization. A randomized controlled trial in a community hospital

BACKGROUND

The wider use of written advance directives is popular but problematic. We have shown previously that acute hospitalization in the era of the Patient Self-Determination Act can facilitate directive discussions and documentation. We investigated whether a simple educational intervention following hospitalization would increase patients' execution of durable health care proxies.

METHODS

We studied a consecutive series of patients (n = 162) recently discharged from the acute care medical service of a community hospital where they had been interviewed about advance directives. The intervention group was randomized to receive an educational brochure and encouragement to execute durable health care proxies. The primary outcome was the proportion of patients in each group with completed durable health care proxies on file in their primary physicians' offices.

RESULTS

Overall, only 20 (12.3%) of 162 patients had documented proxies, 17 of whom (85%) were 65 years of age or older, with no difference between the intervention and control groups (11 [13.3%] of 83 vs nine [11.4%] of 79, respectively). Subgroup analysis of elderly patients also revealed no intervention effect. Univariate analysis revealed three significant predictors of patients' proxy completion: patient age, whether patients had discussed directives in hospital with their physicians, and whether patients' physicians completed proxies for themselves. Multiple logistic regression analysis showed that these three variables interact to predict the probability of patients' executing proxies.

CONCLUSIONS

Simple educational interventions, like those mandated by the Patient Self-Determination Act, are unlikely to increase patients' completion of durable healthcare proxies. Multidimensional interventions that target both elderly patients and their personal physicians should be tested in the future. Discussion in hospital about advance directives can be a useful component of such efforts.

Can we talk? Inpatient discussions about advance directives in a community hospital. Attending physicians' attitudes, their inpatients' wishes, and reported experience

BACKGROUND

The attitudes of hospitalized patients and their attending physicians about advance directives have not been well studied. We compared these attitudes and explored relationships between them and the frequency of actual directives and directive discussions during hospitalization.

METHODS

We conducted scripted interviews with 258 (94.5%) of 273 patients admitted consecutively to the acute medical service of a community teaching hospital in Rochester, NY, and contemporaneously surveyed their attending physicians (n = 68) regarding attitudes about advance directives. Primary outcome measures were patients' willingness to discuss directives, actual physician-patient directive discussions, and patients' preferences for life-sustaining treatments. Also measured were physicians' indications for directive discussions, their reasons not to discuss directives, and their knowledge and attitudes about life-sustaining treatments.

RESULTS

Eighty-one percent (172/212) of competent interviewed patients either did (100) or wanted to (72) discuss advance directives in hospital. Forty-one percent of patients chose to forgo cardiopulmonary resuscitation; 24% to 41% refused other life-sustaining interventions (intensive care unit admission, mechanical ventilation, cardioversion, vasopressors). Overall, 90% (246/273) of all patients met at least one of three criteria reported by their physicians as indications for advance directive discussions: age at least 75 years, critical or potentially fatal illness, and patients' desire to discuss directives. Multiple logistic regression revealed that these same variables predicted patients' willingness to discuss cardiopulmonary resuscitation, their preferences to receive or forgo cardiopulmonary resuscitation, and the frequency of physician-patient discussions about these issues.

CONCLUSIONS

Most medical inpatients in a community hospital want to, are able to, and meet their own physicians' indications to discuss advance directives. Hospitalization presents an unrealized opportunity for physicians and patients to initiate these discussions.

The weight-based heparin dosing nomogram compared with a "standard care" nomogram. A randomized controlled trial

OBJECTIVE

To determine whether an intravenous heparin dosing nomogram based on body weight achieves therapeutic anticoagulation more rapidly than a "standard care" nomogram.

DESIGN

Randomized controlled trial.

SETTING

Two community teaching hospitals in Phoenix, Arizona, and Rochester, New York.

PARTICIPANTS

One hundred fifteen patients requiring intravenous heparin treatment for venous or arterial thromboembolism or for unstable angina.

INTERVENTION

Patients were randomized to the weight-based nomogram (starting dose, 80 units/kg body weight bolus, 18 units/kg per hour infusion) or the standard care nomogram (starting dose, 5000-unit bolus, 1000 units per hour infusion). Activated partial thromboplastin time (APTT) values were monitored every 6 hours, and heparin dose adjustments were determined by the nomograms.

MEASUREMENTS

Activated partial thromboplastin times were measured using a widely generalizable laboratory method. The primary outcomes were the time to exceed the therapeutic threshold (APTT > 1.5 times the control) and the time to achieve therapeutic range (APTT, 1.5 to 2.3 times the control). Bleeding complications and recurrent thromboembolism were also compared.

RESULTS

Kaplan-Meier curves for the primary outcomes favored the weight-based nomogram (P < 0.001 for both). In the weight-based heparin group, 60 of 62 patients (97%) exceeded the therapeutic threshold within 24 hours, compared with 37 of 48 (77%) in the standard care group (P < 0.002). Only one major bleeding complication occurred (in a standard care patient). Recurrent thromboembolism was more frequent in the standard care group; relative risk, 5.0 (95% CI, 1.1 to 21.9).

CONCLUSIONS

The weight-based heparin nomogram is widely generalizable and has proved to be effective, safe, and superior to one based on standard practice.

Intravenous heparin dosing: patterns and variations in internists' practices

OBJECTIVE

To characterize internists' dosing practices when administering and adjusting intravenous heparin regimens.

DESIGN

A survey administered by physician-investigators.

SETTING

Two community teaching hospitals and one Veterans Affairs Medical Center.

SUBJECTS

Sixty-one attending physicians in internal medicine.

MEASUREMENTS

Physicians' choices of therapeutic activated partial thromboplastin time (APTT) range, initial heparin bolus, initial infusion dose, and dose/infusion adjustments when APTT levels are < 1.2 x control (< 35 seconds), 1.2-1.5 x control (35-45 seconds), 1.5-2.3 x control (46-70 seconds), 2.3-3.0 x control (71-90 seconds), and > 3.0 x control (> 90 seconds).

RESULTS

Physicians' dosing decisions and therapeutic ranges during heparin treatment varied widely. Responses to nontherapeutic APTT levels had especially high coefficients of variation (0.67-0.81). Two groups of physicians, together comprising a majority of all respondents, use mutually exclusive therapeutic ranges (mean 44-56 seconds and 60-83 seconds). These two groups differ significantly in several types of dosing decisions.

CONCLUSION

In the absence of generalizable standard guidelines for intravenous heparin therapy, internists' dosing practices vary widely. Because such practices may impede timely, effective anticoagulation, experimental studies comparing standardized dosing protocols are needed.

Relationship of maternal and perinatal conditions to eventual adolescent suicide

In an investigation of a possible relationship between falling perinatal mortality and rising rates of adolescent suicide, 46 risk factors from the prenatal, birth, and neonatal records of 52 adolescents who committed suicide before age 20 and 2 matched controls for each subject were analysed blind. The results showed statistically significant differences between the suicide victims and each of the controls and no difference between the controls. Three specific risk factors were shown to have a powerful capacity to differentiate the suicides from the controls: (i) respiratory distress for more than 1 h at birth; (ii) no antenatal care before 20 weeks of pregnancy; and (iii) chronic disease of the mother during pregnancy.

The stability and interrelationships of newborn sucking and heart rate

The sucking behavior of 44 newborns was recorded along with heart rate (HR) and respiration. These 3 systems showed stability over a 24-hr period. Sucking parameters varied markedly depending upon whether the infant was sucking for sucrose or under a no-fluid condition. Moreover, HR was strikingly affected by sweetness. The direction of HR change was toward increasing rates when sucking for sweet, even though sucking for sweet substances occurs more slowly than for no fluid.