David L. Howard
Johns Hopkins University
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Featured researches published by David L. Howard.
The New England Journal of Medicine | 2000
G. Michael Felker; Richard E. Thompson; Joshua M. Hare; Ralph H. Hruban; Diedre E. Clemetson; David L. Howard; Kenneth L. Baughman; Edward K. Kasper
BACKGROUND Previous studies of the prognosis of patients with heart failure due to cardiomyopathy categorized patients according to whether they had ischemic or nonischemic disease. The prognostic value of identifying more specific underlying causes of cardiomyopathy is unknown. METHODS We evaluated the outcomes of 1230 patients with cardiomyopathy. The patients were grouped into the following categories according to underlying cause: idiopathic cardiomyopathy (616 patients), peripartum cardiomyopathy (51); and cardiomyopathy due to myocarditis (111), ischemic heart disease (91), infiltrative myocardial disease (59), hypertension (49), human immunodeficiency virus (HIV) infection (45), connective-tissue disease (39), substance abuse (37), therapy with doxorubicin (15), and other causes (117). Cox proportional-hazards analysis was used to assess the association between the underlying cause of cardiomyopathy and survival. RESULTS During a mean follow-up of 4.4 years, 417 patients died and 57 underwent cardiac transplantation. As compared with the patients with idiopathic cardiomyopathy, the patients with peripartum cardiomyopathy had better survival (adjusted hazard ratio for death, 0.31; 95 percent confidence interval, 0.09 to 0.98), and survival was significantly worse among the patients with cardiomyopathy due to infiltrative myocardial disease (adjusted hazard ratio, 4.40; 95 percent confidence interval, 3.04 to 6.39), HIV infection (adjusted hazard ratio, 5.86; 95 percent confidence interval, 3.92 to 8.77), therapy with doxorubicin (adjusted hazard ratio, 3.46; 95 percent confidence interval, 1.67 to 7.18), and ischemic heart disease (adjusted hazard ratio, 1.52; 95 percent confidence interval, 1.07 to 2.17). CONCLUSIONS The underlying cause of heart failure has prognostic value in patients with unexplained cardiomyopathy. Patients with peripartum cardiomyopathy appear to have a better prognosis than those with other forms of cardiomyopathy. Patients with cardiomyopathy due to infiltrative myocardial diseases, HIV infection, or doxorubicin therapy have an especially poor prognosis.
Cancer Research | 2005
Diana Mandelker; Keishi Yamashita; Yutaka Tokumaru; Koshi Mimori; David L. Howard; Yoichi Tanaka; André Lopes Carvalho; Wei Wen Jiang; Hannah Lui Park; Myoung Sook Kim; Motonobu Osada; Masaki Mori; David Sidransky
PGP9.5/UCHL1 is a member of the carboxyl-terminal ubiquitin hydrolase family with a potential role in carcinogenesis. We previously identified PGP9.5 as a putative tumor-suppressor gene and methylation of the promoter as a cancer-specific event in primary cancer tissues. In this current study, we analyzed PGP9.5 methylation in 50 esophageal squamous cell carcinoma (ESCC) primary tumors with well characterized clinicopathologic variables including patient outcome. Two independent modalities for methylation analysis (TaqMan methylation-specific PCR and combined bisulfite restriction analysis) were used to analyze these samples. The two data sets were consistent with each other, as the 21 patients (42%) with highest methylation levels by TaqMan analysis all showed visible combined bisulfite restriction analysis bands on acrylamide gels. Using an optimized cutoff value by TaqMan quantitation, we found that patients with higher PGP9.5 methylation ratios in the primary tumor showed poorer 5-year survival rates than those without PGP9.5 methylation (P = 0.01). A significant correlation was also seen between PGP9.5 promoter methylation and the presence of regional lymph node metastases (P = 0.03). Multivariate analysis subsequently revealed that PGP9.5 methylation was an independent prognostic factor for ESCC survival (P = 0.03). These results suggest that PGP9.5 promoter methylation could be a clinically applicable marker for ESCC progression.
Journal of General Internal Medicine | 2004
David L. Howard; Jeffery H. Silber; David R. Jobes
AbstractOBJECTIVE: To conduct a statewide analysis of the effect of New York’s regulations, limiting internal medicine and family practice residents’ work hours, on patient mortality. DESIGN: Retrospective study of inpatient discharge files for 1988 (before the regulations) and 1991 (after the regulations). SETTING AND PATIENTS: Adult patients discharged from New York teaching hospitals (170,214) and nonteaching hospitals (143,455) with a principal diagnosis of congestive heart failure, acute myocardial infarction, or pneumonia, for the years 1988 and 1991 (periods before and after Code 405 regulations went into law). Patients from nonteaching hospitals served as controls. MEASUREMENT: In-hospital mortality. RESULTS: Combined unadjusted mortality for congestive heart failure, acute myocardial infarction, and pneumonia patients declined between 1988 and 1991 in both teaching (14.1% to 13.0%; P=.0001) and nonteaching hospitals (14.0% to 12.5%; P=.0001). Adjusted mortality also declined between 1988 and 1991 in both teaching (odds ratio [OR], death 1991/1988, 0.868; 95% confidence interval [CI], 0.843 to 0.894; P=.0001) and nonteaching hospitals (OR, death 1991/1988, 0.853; 95% CI, 0.826 to 0.881; P=.0001). This beneficial trend toward lower mortality over time was nearly identical between teaching and nonteaching hospitals (P=.4348). CONCLUSION: New York’s mandated limitations on residents’ work hours do not appear to have positively or negatively affected in-hospital mortality from congestive heart failure, acute myocardial infarction, or pneumonia in teaching hospitals.
Journal of Acquired Immune Deficiency Syndromes | 2006
David L. Howard; Carl A. Latkin
Objectives: To examine factors associated with noninjectors having 1 or more injection drug users as sex partners. Methods: We collected data as a part of the Self-Help in Eliminating Life Threatening Diseases study, a network-oriented experimental HIV prevention intervention. All eligible participants were administered a detailed face-to-face interview on their sociodemographic background, patterns of drug use, HIV prevention and risk behaviors, and social networks. The sample for these analyses consisted of 863 noninjectors, 97 of whom had 1 or more injection drug-using sex partners. Results: Among the factors associated with an increased odds of having 1 or more injecting sex partners were long-term unemployment, increasing proportion of women in network (among male noninjectors), increasing number of recent sex partners (among former injectors), increasing number of injecting non-sex partners in the network, and increasing network size above 15. Conclusions: There are specific network characteristics associated with noninjectors having injecting sex partners.
Critical Care Medicine | 2009
David J. Murphy; David L. Howard; Angela Muriithi; Pedro A. Mendez-Tellez; Jonathan Sevransky; Carl Shanholtz; Giora Netzer; Peter J. Pronovost; Dale M. Needham
Objective:To describe red blood cell (RBC) transfusion practices and evaluate the association between patient-related factors and pretransfusion hemoglobin concentration in acute lung injury (ALI). Design:Secondary analysis of prospectively collected data. Setting:Nine intensive care units (ICUs) in three teaching hospitals in Baltimore, MD. Patients:Two hundred forty-nine consecutive patients with ALI requiring mechanical ventilation. Interventions:None. Measurements and Main Results:Simple and multiple linear regression analyses were used to evaluate the association between the nadir hemoglobin concentration on the day of initial RBC transfusion and 20 patient-level demographic, clinical and ICU treatment factors as well as ICU type. Of 249 patients with ALI, 47% received an RBC transfusion in the ICU without evidence of active hemorrhage or acute cardiac ischemia. The mean (sd) nadir hemoglobin on the day of first transfusion was 7.7 (1.1) g/dL with 67%, 36%, 15%, and 5% of patients transfused at >7, >8, >9, and >10g/dL, respectively. Transfused patients received a mean (sd) of 5 (6) RBC units from ALI diagnosis to ICU discharge. Prehospital use of iron or erythropoietin and platelet transfusion in the ICU were independently associated with lower pretransfusion hemoglobin concentrations. No patient factors were associated with higher hemoglobin concentrations. Admission to a surgical (vs. medical) ICU was independently associated with a 0.6 g/dL (95% confidence interval 0.1–1.1 g/dL) higher pretransfusion hemoglobin. Conclusions:Patients with ALI commonly receive RBC transfusions in the ICU. The pretransfusion hemoglobin observed in our study was lower than earlier studies, but a restrictive strategy was not universally adopted. Patient factors do not explain the gap between clinical trial evidence and routine transfusion practices. Future studies should further explore ICU- and physician-related factors as a source of variability in transfusion practice.
Journal of Pediatric and Adolescent Gynecology | 2013
David L. Howard; Rebecca Wayman; Julie L. Strickland
STUDY OBJECTIVE No prior study has directly compared satisfaction with Depo-Provera to the Mirena intra-uterine device (IUD) among post-partum parous adolescents. Our aim was to make this comparison among post-partum adolescents at 3, 6, and 12 months of follow-up. PARTICIPANTS Post-partum/parous adolescents (aged 20 and younger) choosing either Depo-Provera or the Mirena IUD as their method of contraception. DESIGN Prospective longitudinal survey. SETTING The adolescent clinic at the Truman Medical Center, Kansas City Missouri. MAIN OUTCOME MEASURE Satisfaction with and intention to continue the chosen method at 3, 6, and 12 months of follow-up. INTERVENTIONS None. RESULTS Sixty-six post-partum/parous adolescents were recruited, 37 choosing the Mirena IUD and 29 choosing Depo-Provera for contraception. The 2 groups had similar baseline characteristics. There was no statistically significant difference in overall satisfaction with Depo-Provera versus the Mirena IUD at 3, 6, or 12 months of follow-up. For both contraceptive methods, unpredictable bleeding was most unacceptable at 6 months of follow-up but the trend was only statistically significant for Depo-Provera. For Depo-Provera, there was a significantly lower proportion of participants actually continuing the method at 12 months (42.9%) relative to the proportion who at 6 months had expressed an intention to continue (80.0%; P = .01). This trend was not seen for the Mirena IUD. CONCLUSION Among post-partum/parous adolescents, overall subjective satisfaction with Depo-Provera and the Mirena IUD is similarly high over 12 months of follow-up. With Depo-Provera, however, there appears to be a disconnect between intention to continue at 6 months and actual continuation at 12 months.
Maternal and Child Health Journal | 2009
David L. Howard; Donna M. Strobino; Susan G. Sherman; Rosa M. Crum
Objectives To examine whether there are racial differences in the relation between the timing of incarceration during pregnancy and birth outcomes among incarcerated pregnant women. Methods We examined the medical records associated with 360 infants born to pregnant inmates in Texas state prisons between January 1, 2002 and December 31, 2004. Weighted linear regression was used, within racial strata, to model gestational age at delivery, and infant birth weight, respectively, as functions of gestational age at maternal admission to prison. Models were adjusted for maternal age; gravidity; educational attainment; history of tobacco, substance, and alcohol use and the presence of any maternal chronic disease. Results Among Whites there was a 360.8 g lower mean birth weight for infants born to women incarcerated during weeks 14–20 relative to infants born to women incarcerated during weeks 1–13 (p < 0.10). Among Blacks and Hispanics, incarceration after the first trimester was not associated with a significant decrease in infant birth weight relative to incarceration during the first trimester. White women entering prison during the first trimester delivered infants at higher gestational ages than White women entering in the second trimester but the opposite was the case for Hispanics. Conclusions The association between the quantity of exposure to prison during pregnancy and birth outcomes appears to be different for Blacks, Whites, and Hispanic women. Future studies of the effect of incarceration on pregnancy outcomes should attempt to uncover potential racial differences in trends by obtaining racially stratified results or by assessing interaction with race.
Journal of Minimally Invasive Gynecology | 2012
David L. Howard; Paul J. Christenson; Julie L. Strickland
In previous case-reports of Essure microinsert perforation, the microinsert was successfully removed at laparoscopy. Herein is discussed the scenario of persistent pelvic pain over several years after an apparently successful laparoscopic retrieval of a perforating right-sided microinsert. In the interim, the patient underwent 2 unsuccessful exploratory laparotomy procedures in an attempt to retrieve additional microinsert fragments that had perforated the uterus. Successful management of Essure microinsert perforation in this patient ultimately required use of intraoperative fluoroscopy. Surgeons performing laparoscopy or laparotomy to retrieve Essure microinserts that have perforated should be aware that these are not always visible to the naked eye, and there should be a low threshold to use intraoperative fluoroscopy to ensure that all perforating fragments have been removed.
Paediatric and Perinatal Epidemiology | 2008
David L. Howard; Donna M. Strobino; Susan G. Sherman; Rosa M. Crum
There is still controversy surrounding the effectiveness of prenatal care in reducing low birthweight. In addition, very few studies have assessed the relationship between prenatal care and infant birthweight among pregnant women within the prison system. We sought to ascertain whether there is an association between the quantity of prenatal care and infant birthweight among pregnant women within such a setting. We examined the prison medical records of 147 infants born to women delivering at term (37-41 weeks of gestation) between 1 January 2002 and 31 December 2004 who were incarcerated during pregnancy in Texas state prisons. Linear regression was used to evaluate the association between the number of prison prenatal care visits and infant birthweight while adjusting for potential confounders (age, gravidity, maternal education, maternal race, history of substance use, history of alcohol use, history of tobacco use and the presence of any chronic disease). We also adjusted for the interaction between the gestational age at admission to prison and the number of prison prenatal care visits. There was a statistically significant 120.5 g increase in adjusted mean birthweight with each additional prison prenatal care visit (P = 0.001) among study infants whose mothers entered prison during the first trimester. This trend was not observed among women who came in after the first trimester. There appears to be a positive association between the amount of prison prenatal care and infant birthweight among incarcerated pregnant women delivering at term, but this association appears to be limited to women entering prison during the first trimester of pregnancy.
Journal of Minimally Invasive Gynecology | 2018
David L. Howard; Andrea McGlynn; Joy A. Greer
STUDY OBJECTIVE To compare 12-month postoperative complication rates in women who underwent sling procedures by high-volume versus low-volume surgeons at US military treatment facilities (MTFs). DESIGN Retrospective cohort study (Canadian Task Force classification II-2). SETTING US MTFs. PATIENTS Female military beneficiaries enrolled in TRICARE. INTERVENTIONS Sling surgery for stress urinary incontinence between January 1, 2011 and December 31, 2012. MEASUREMENTS AND MAIN RESULTS The primary exposure was surgeon volume (high vs low). Surgeon volume was categorized as high or low based on the number of slings performed in the previous 2 years at US MTFs (January 1, 2009 to December 31, 2010). The primary outcome was a composite variable indicating at least 1 postoperative complication within 12 months. We used International Classification of Diseases, 9th revision and Current Procedural Terminology codes to identify postoperative complications that occurred in the 12 months after the index sling procedure. During the study period 348 gynecologic and urologic surgeons performed 1632 slings. The average patient age was 47.2 years. Based on our data distribution we classified surgeons as high volume (>12 slings/2 years) or low volume (<4 slings/2 years). High-volume surgeons operated on patients who were older, more likely to have comorbidities, and more likely to receive concomitant prolapse surgery. Using a cluster analysis the overall likelihood of at least 1 postoperative complication in 12 months for high-volume versus low-volume surgeons was 48.4% versus 42.2% (adjusted odds ratio, 1.24; 95% confidence interval, .99-1.54; p = .06). There were no differences between high- and low-volume surgeons in the rate of almost all other postoperative complications. CONCLUSION No significant differences in 12-month complication rates after sling surgery, stratified by surgeon volume, were seen in a setting of overall low-volume military surgeons.