Joseph K. Canner
Johns Hopkins University
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Featured researches published by Joseph K. Canner.
The Lancet | 1994
Richard D. Semba; John D. Chiphangwi; Paolo G. Miotti; G.A Dallabetta; Donald R. Hoover; Joseph K. Canner; Aj Saah
Studies show that around 10-40% HIV-positive women will give birth to children who are also infected. However, the risk factors for transmission from mother to child are not well understood and the effects of maternal nutritional status are unknown. We conducted a study of vitamin A status in pregnant women as a risk factor for mother-to-child transmission of HIV in Malawi. Serum vitamin A, height, weight, CD4 T-cell counts, and duration of breastfeeding were measured in 338 HIV-positive mothers whose infants HIV serostatus was known. Mother-to-child transmission of HIV was 21.9% among mothers whose infants survived to 12 months of age. Mean vitamin A concentration in 74 mothers who transmitted HIV to their infants was lower than that in 264 mothers who did not transmit HIV to their infants (0.86 [0.03] vs 1.07 [0.02], p < 0.0001). We divided HIV positive mothers to 4 groups, those with vitamin A concentrations of less than 0.70, between 0.70 and 1.05, between 1.05 and 1.40, and greater than or equal to 1.40 mumol/L. The mother-to-child transmission rates for each group were 32.4%, 26.2%, 16.0%, and 7.2%, respectively (p < 0.0001). Maternal CD4 cell counts, CD4%, and CD4/CD8 ratio were also associated with increased mother-to-child transmission of HIV. Maternal age, body-mass index, and breastfeeding practices were not significantly associated with higher mother-to-child transmission. Our study suggests that maternal vitamin A deficiency contributes to mother-to-child transmission of HIV.
Diabetes Care | 1994
Jonathan C. Javitt; Lloyd Paul Aiello; Yen-Pin Chiang; Frederick L. Ferris; Joseph K. Canner; Sheldon Greenfield
OBJECTIVE Diabetic retinopathy, which leads to macular edema and retinal neovascularization, is the leading cause of blindness among working-age Americans. Previous research has demonstrated significant cost savings associated with detection of eye disease in Americans with type 1 diabetes. However, detection and treatment of eye disease among those with type II diabetes was previously thought not to be cost-saving. Our purpose was to estimate the current and potential federal savings resulting from the screening and treatment of retinopathy in patients with type II diabetes, based on recently availabledata concerning efficacy of treating both macular edema and neovascularization along withnew data on federal budgetary costs of blindness. RESEARCH DESIGN AND METHODS We used computer modeling, incorporating data from population-based epidemiological studies and multicenter clinical trials. Monte Ciarlosimulation was used, combined with sensitivity analysis and present value analysis of cost savings. RESULTS Screening and treatment for eye disease in patients with type II diabetes generates annual savings of
Ophthalmology | 1992
Jonathan C. Javitt; James M. Tielsch; Joseph K. Canner; Margaret M. Kolb; Alfred Sommer; Earl P. Steinberg; Marilyn Bergner; Gerard F. Anderson; Eric B Bass; Alan M. Gittelsohn; Marcia W. Legro; Neil R. Powe; Oliver P. Schein; Phoebe Sharkey; Donald M. Steinwachs; Debra A. Street; Donald J. Doughman; Merton Flom; Thomas S. Harbin; Harry L.S. Knopf; Thomas Lewis; Stephen A. Obstbaum; Denis M. O'Day; Walter J. Stark; Arlo C. Terry; C. Pat Wilkinson
247.9 million to the federal budget and 53,986 person-years of sight, even at current suboptimal (60%) levels of care. If all patients with type II diabetes receive recommended care, the predicted net savings (discounted at 5%) exceeds
Ophthalmology | 1994
Jonathan C. Javitt; Debra A. Street; James M. Tielsch; Qin Wang; Margaret M. Kolb; Oliver D. Schein; Alfred Sommer; Marilyn Bergner; Earl P. Steinberg; Gerard F. Anderson; Eric B Bass; Joseph K. Canner; Alan M. Gittelsohn; Marcia W. Legro; Neil R. Powe; Oliver P. Schein; Phoebe Sharkey; Donald M. Steinwachs
472.1 million and 94,304 person-years of sight. Nearly all savings areassociated with detection and treatment of diabetic macular edema. Enrolling each additional person with type II diabetes into currently recommended ophthalmological care resultsin an average net savings of
Ophthalmology | 1989
Jonathan C. Javitt; Joseph K. Canner; Alfred Sommer
975/person, even if all costs of care are borne by the federal government. CONCLUSIONS Our analysis indicates that prevention programs aimed at improving eye care for patients with diabetes not only reduce needless vision loss but also willprovide a financial return on the investment of public funds.
Ophthalmology | 1991
Jonathan C. Javitt; Lloyd Paul Aiello; Lauri J. Bassi; Yen Pin Chiang; Joseph K. Canner
PURPOSE The authors studied 57,103 randomly selected Medicare beneficiaries who underwent extracapsular cataract extraction in 1986 or 1987 to determine the possible association between performance of neodymium (Nd):YAG laser capsulotomy and the risk of subsequent retinal break or detachment. METHODS Cases of cataract surgery were identified from Medicare claims submitted in 1986 and 1987 and were followed through the end of 1988. Episodes of cataract surgery, posterior capsulotomy, and retinal complications were ascertained based on procedure and diagnosis codes listed in physician bills and hospital discharge records. Lifetable and Coxs proportional hazards models were used to analyze the risk of retinal detachment or break in patients undergoing and not undergoing capsulotomy during the period of observation. RESULTS Of the 57,103 persons identified as having undergone extracapsular cataract extraction in 1986 or 1987, 13,709 subsequently underwent Nd:YAG laser capsulotomy between 1986 and 1988. A total of 337 persons had aphakic or pseudophakic retinal detachments between 1986 and 1988 and an additional 194 underwent repair of a retinal break. Proportional hazards modeling shows a 3.9-fold increase in the risk of retinal break or detachment among those who underwent capsulotomy (95% confidence interval: 2.89 to 5.25). Younger patient age, male sex, and white race also were associated with increased risk of retinal complications after extracapsular cataract extraction. CONCLUSION The authors conclude that there is a statistically significant increase in the risk of retinal detachment or break in those patients who undergo capsulotomy after cataract extraction. Therefore, capsulotomy should be deferred until the patients impairment caused by capsular opacification warrants the increased risk of retinal complications associated with performance of capsulotomy.
AIDS | 1995
Gina Dallabetta; Paolo G. Miotti; John D. Chiphangwi; George N. Liomba; Joseph K. Canner; Alfred J. Saah
Background: A near-total shift to cataract extraction on an outpatient basis occurred as a result of an administrative ruling by the Health Care Financing Administration. No national study has been conducted to assess the possible effects of that decision on clinical outcomes of surgery. The authors compared the rates of retinal detachment (RD) repair and hospitalization for endophthalmitis after extracapsular cataract extraction (ECCE) (including phacoemulsification) in 1986 and 1987 with those following inpatient cataract extraction in 1984. Methods: Using the 5% random sample of Medicare beneficiaries, we analyzed the claims of all individuals 66 years of age or older who underwent ECCE by nuclear expression or phacoemulsification in 1986 and 1987. A total of 57,103 patients were identified and followed to the end of 1988. Cumulative probability of RD repair and hospitalization for endophthalmitis was calculated by standard lifetable methods. These findings were compared with the cumulative probability of the same complications in a cohort of 330,000 patients who underwent cataract extraction on an inpatient basis in 1984. Results: In the 1986-to-1987 cohort, the cumulative probability of RD within 3 years after cataract surgery was 0.81% and the cumulative probability of endophthalmitis within 1 year was 0.08%. The rate of RD is similar to that which we previously reported for 330,000 patients who underwent inpatient surgery in 1984, but the rate of endophthalmitis is significantly lower in the 1986-to-1987 outpatient cohort (0.08% versus 0.12%; z = 2.42; P = 0.01). Conclusions: The shift to outpatient cataract surgery was accompanied by no significant increase in the probability of RD repair and possibly a significant decrease in the rate of hospitalization for endophthalmitis.
JAMA Surgery | 2015
Mahmoud B. Malas; Joseph K. Canner; Caitlin W. Hicks; Isibor Arhuidese; Devin S. Zarkowsky; Umair Qazi; Eric B. Schneider; James H. Black; Dorry L. Segev; Julie A. Freischlag
Diabetic retinopathy is a leading cause of blindness among working age Americans. The epidemiology of diabetic eye disease has been well described in population-based studies and the effects of laser treatment have been tested in randomized controlled trials. The authors have designed a computer simulation model using the published reports of these studies to predict the medical and economic effects of applying currently accepted methods for the control of diabetic retinopathy to the population of type I diabetics. Recommendations for screening are taken from the Public Health Committee of the American Academy of Ophthalmology. Treatment recommendations and treatment efficacy are drawn from the reports of the Diabetic Retinopathy Study (DRS) and the Early Treatment Diabetic Retinopathy Study (ETDRS). Costs of screening and treatment are drawn from published Medicare reimbursement data. Over a 60-year period, the model predicts that proliferative diabetic retinopathy (PDR) requiring panretinal photocoagulation (PRP) will eventually develop in 72% of type I diabetics and macular edema will develop in 42%. If these treatments are delivered as recommended in the clinical trials, the model predicts a cost of
AIDS | 1996
Taha E. Taha; Joseph K. Canner; John D. Chiphangwi; Gina Dallabetta; Li Ping Yang; Laban Mtimavalye; Paolo G. Miotti
966 per person-year of vision saved from proliferative retinopathy and
Transactions of The Royal Society of Tropical Medicine and Hygiene | 1994
Taha E. Taha; Joseph K. Canner; Gina A. Dallabetta; John D. Chiphangwi; George N. Liomba; Anne Marie Wangel; Alfred J. Saah; Paolo G. Miotti
1118 per person-year of central acuity saved from macular edema. This is only one seventh of the