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COST EFFECTIVENESS OF MEDICAL DEVICES TO REDUCE MORTALITY FROM PRE-ECLAMPSIA IN LOW-INCOME COUNTRIES Zoë M. McLaren 1 , John P. Hessburg 2 , James Akazili 3 , Amir Sabet Sarvestani 4 , Timothy R. B. Johnson 5 and Kathleen H. Sienko 2,6 Health Management and Policy, University of Michigan 1 ; Department of Biomedical Engineering, University of Michigan 2 ; Navrongo Health Research Centre 3 ; Design Science Program, University of Michigan 4 ; Department of Obstetrics and Gynecology, University of Michigan 5 ; Department of Mechanical Engineering, University of Michigan 6 AKNOWLEDGMENTS The authors are grateful to David Hutton, David Mendez, Lisa Prosser and participants at the American Society of Health Economics conference (2012) for their suggestions and comments. Yi Mao provided research assistance. Following funding supports are acknowledged: University of Michigan Center for Global Health Jr. Faculty Engagement Award (Sienko); University of Michigan Institute for Research on Women and Gender’s Faculty Seed Grant (McLaren); Fogarty International Center at the National Institutes of Health, Grant Number 1R24TW008814 – 01: Ghana-Michigan Postdoctoral And Research Training NetwoRk (PARTNER) Program (Sienko, Akazili); National Science Foundation Graduate Research Fellowship (Sabet Sarvestani). Category Device Type Device Description Per-use Cost ($) Sens. Spec. Diagnostic: Proteinuria Dipstick Test A Single use plastic strips, detect albumin and creatinine in urine. 0.57 0.96 0.53 B Single use plastic strips, detect protein in urine. 5.00 0.26 0.73 C Single use plastic strips, detect glucose and protein in urine. 0.20 0.68 0.68 D Automated, battery-operated device, displays protein content of urine sample on LCD screen. 10.00 0.99 0.84 Diagnostic: Blood- pressure Auscultatory E Mercury column displays pressure of cuff inflated around upper arm. Manual device, requires trained operator to listen to blood sounds with a stethoscope. 0.01- 0.04 0.97 0.88 Hybrid F Hybrid device with manual auscultatory and automatic oscillometric settings. 0.01 0.92 0.91 Oscillometric G Battery powered device, automatic cuff. Obtains blood pressure through built-in algorithm, displays result on digital readout. 0.01- 0.27 0.93 0.86 H Manually inflated device, automatically determines blood pressure with built- in algorithm, displays results digitally. 0.004 0.91 0.91 Device Effectiveness Device DALYs averted ICER No device 0 0 H 0.0036 1.11 F 0.0036 167.68 E 0.0038 157.10 D 0.0039 90139.08 DECISION TREE Parameter Baseline Values % of pregnancies that are pre-eclamptic 2.80% % of pregnancies tested for pre-eclampsia 51.00% Survival rate for undiagnosed or untreated pre-eclampsia 94.40% % of diagnosed pre-eclampsia treated 16.00% Success rate of treatment among pre-eclamptic pregnancies 99.20% Survival rate for successfully treated pre-eclamptic pregnancies 99.43% Survival rate for unsuccessfully treated pre-eclamptic pregnancies 94.40% Rate of complications for pre-eclampsia survivors 3.80% HRQL for lifetime following severe complications 0.25 Life expectancy 55 years Discount rate 3.00% Sensitivity analysis for “device H” base case scenario ($/DALY) Base case 0.495 (CI 0.086-1.984) Tested rate Treated Rate Device sensitivity 20 0.488 (0.080-1.963) 20 0.383 (0.067-1.525) 70 0.641 (0.105-2.676) 40 0.495 (0.082-2.007) 40 0.186 (0.034-0.743) 80 0.562 (0.096-2.221) 60 0.502 (0.081-2.057) 60 0.124 (0.023-0.508) 90 0.491 (0.082-1.955) 80 0.492 (0.083-1.946) 80 0.093 (0.018-0.394) 95 0.476 (0.079-1.984) 99 0.444 (0.073-1.762) 99.5 0.454 (0.075-1.804) Device A: CLINITEK Microalbumin strip test, B: Multistix Pro 10LS, C: Uristik, D: DCA 2000+, E: Mercury Sphygmo-manometer, F: Nissei DM-2000, G: Spot Vital Signs, H: Microlife BACKGROUND • Over 280,000 women die each year from complications related to childbirth • Majority of deaths in low-income countries (LICs) • Post-partum hemorrhage, pre-eclampsia, infection, obstructed labor and anemia account for >75% of deaths • Low-cost medical devices key to reducing preventable mortality • Pre-eclampsia (gestational hypertension) diagnosed when blood pressure >140/90 mmHg and proteinuria >30 mg/dL • Most common treatment is IV magnesium sulfate • May be followed by delivery through induction of labor or cesarean section • Pre-eclampsia accounts for 10-25% of maternal mortality in LICs This is the first study to generate and compare cost-effectiveness ratios for medical devices designed for LICs. METHODS • Devices identified through PubMed, SciVerse Scopus, WHO Compendium of New and Emerging Health Technologies, Medline, appropedia.org, and device developers • Effectiveness values determined through published literature, unpublished studies, product developers and experts in field • Cost data obtained from online databases and communication with product developers and distributors • Decision tree models probability that a pregnant woman is tested for pre-eclampsia, correctly diagnosed, and successfully treated (Fig. 1) • Terminal node indicates DALYs associated with particular sequence of outcomes • Sensitivity and specificity parameters vary by device • Blood pressure device sensitivity and specificity calculated using bias-corrected modeling methodology • One-way sensitivity analysis and second-order probabilistic multivariate sensitivity analysis evaluates robustness of findings to changes in parameter values CONCLUSIONS • Low-cost, easy to use blood pressure measurement devices performed best in cost effectiveness analysis • Simple devices more cost-effective than complex devices in LICs • Estimates not sensitive to changes in testing rate or device sensitivity, are sensitive to changes in treatment rate • Reasonably sensitive low cost devices preferred to highly-sensitive but high-cost devices • Need for more effectiveness data for existing devices to widen range of devices included in analyses • Limitation is lack of data on several input parameters, and on medical device effectiveness and maternal mortality in general • Goal to generate cost-effectiveness estimates to guide decision-making in clinical practice and public health policy to ultimately reduce maternal mortality in low income countries RESULTS 3 4 1 2 Figure 1: Decision tree used for cost-effectiveness analysis of devices.
