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Ramsey SD, McCune JS, Blough DK, McDermott CL, Beck SJ, López JA, Deeg HJ. Patterns of blood product use among patients with myelodysplastic syndrome. Vox Sang 2011; 102:331-7. [PMID: 22115321 DOI: 10.1111/j.1423-0410.2011.01568.x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
BACKGROUND AND OBJECTIVES Most patients with myelodysplastic syndrome (MDS) require blood product support to manage the severe anaemias, which frequently accompany MDS. Our objective was to show the feasibility of linking the Surveillance, Epidemiology and End Results (SEER) database with records from Puget Sound Blood Center (PSBC) to characterize blood product use over time in successive cohorts of patients with MDS. MATERIALS AND METHODS We identified patients with MDS in the SEER registry. The cohort was then linked to PSBC records to discern blood product use. RESULTS Included in the analysis were 783 patients with MDS entered in the SEER database from 2001 to 2007 for whom data were also available in the PSBC database. Among patients with MDS who received transfusions, 97% received packed red blood cells; 52% received platelets. The proportion of patients with MDS receiving blood products declined from 2001 to 2007. CONCLUSION These data show a recent decline in blood product use for patients with MDS. Future studies are needed to further evaluate the reasons for this finding, specifically exploring the impact of newer medications on blood product use in patients with MDS.
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Affiliation(s)
- S D Ramsey
- Research and Economic Assessment in Cancer and Healthcare (REACH) Group, Fred Hutchinson Cancer Research Center, Seattle, WA 98109-1024, USA.
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Shankaran V, Beck SJ, Blough DK, Koepl L, Yim YM, Yu E, Ramsey SD. Survival trends and patterns of chemotherapy use in elderly metastatic colorectal cancer (mCRC) patients. J Clin Oncol 2011. [DOI: 10.1200/jco.2011.29.15_suppl.6118] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
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Shankaran V, Beck SJ, Blough DK, Yim Y, Yu E, Ramsey SD. Patterns of care and survival trends in elderly metastatic colorectal cancer patients: A SEER-Medicare analysis. J Clin Oncol 2011. [DOI: 10.1200/jco.2011.29.4_suppl.520] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
520 Background: Over the last decade, the treatment of metastatic colorectal cancer (mCRC) has changed dramatically as new drugs and hepatic resection have been incorporated into practice. The goal of this study is to examine treatment patterns and survival trends for older patients (pts) with mCRC. Methods: Pts ≥ age 65 with mCRC diagnosed (dx) 2001-2005 were identified from the SEER-Medicare database. Pts were excluded for lack of Medicare parts A and B in the year prior to dx, second malignancy, or non- adenocarcinoma histology. First-line (1L) chemotherapy (CTx) use was identified by claims within 3 months of dx. Metastatectomy was identified by various claims for liver resection. Comorbidity was assessed by Klabunde index. A Cox proportional hazards regression model was used to assess the effect of demographic and treatment factors on survival. Results: A total of 5,725 pts (median age 77) met inclusion criteria. 274 pts (5%) underwent hepatic resection and 2,647 (46%) received CTx. From 2001-2003, 43% of pts received 1L CTx (34% and 1% with regimens containing irinotecan (Iri) and oxaliplatin (Ox) and 49% with 5-FU/cap alone). From 2004-2005, 51% of pts received 1L CTx (25%, 14%, and 37% with regimens containing bevacizumab (Bv), Iri, and Ox and 40% with 5-FU/cap alone). In the multivariate analysis using the Cox proportional hazards model, survival was significantly improved in pts receiving CTx or hepatic resection and in pts dx 2004-2005 (Table). Conclusions: In an older mCRC population, hepatic resection, CTx use, and mCRC dx in 2004-2005 are associated with improved survival. Improved survival of pts dx in 2004-2005 coincides with the 2004 approval dates and uptake of Bv and Ox, and may be associated with the use of these therapies. Further analysis will examine the associations between specific Ctx regimens, Bv, and survival and will include pts dx through 2007. [Table: see text] [Table: see text]
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Affiliation(s)
- V. Shankaran
- Seattle Cancer Care Alliance/Fred Hutchinson Cancer Research Center, Seattle, WA; Fred Hutchinson Cancer Research Center, Seattle, WA; University of Washington, Seattle, WA; Genentech, South San Francisco, CA
| | - S. J. Beck
- Seattle Cancer Care Alliance/Fred Hutchinson Cancer Research Center, Seattle, WA; Fred Hutchinson Cancer Research Center, Seattle, WA; University of Washington, Seattle, WA; Genentech, South San Francisco, CA
| | - D. K. Blough
- Seattle Cancer Care Alliance/Fred Hutchinson Cancer Research Center, Seattle, WA; Fred Hutchinson Cancer Research Center, Seattle, WA; University of Washington, Seattle, WA; Genentech, South San Francisco, CA
| | - Y. Yim
- Seattle Cancer Care Alliance/Fred Hutchinson Cancer Research Center, Seattle, WA; Fred Hutchinson Cancer Research Center, Seattle, WA; University of Washington, Seattle, WA; Genentech, South San Francisco, CA
| | - E. Yu
- Seattle Cancer Care Alliance/Fred Hutchinson Cancer Research Center, Seattle, WA; Fred Hutchinson Cancer Research Center, Seattle, WA; University of Washington, Seattle, WA; Genentech, South San Francisco, CA
| | - S. D. Ramsey
- Seattle Cancer Care Alliance/Fred Hutchinson Cancer Research Center, Seattle, WA; Fred Hutchinson Cancer Research Center, Seattle, WA; University of Washington, Seattle, WA; Genentech, South San Francisco, CA
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Smith DH, Johnson ES, Thorp ML, Petrik A, Yang X, Blough DK. Outcomes predicted by phosphorous in chronic kidney disease: a retrospective CKD-inception cohort study. Nephrol Dial Transplant 2009; 25:166-74. [DOI: 10.1093/ndt/gfp387] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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McConn DJ, Lin YS, Mathisen TL, Blough DK, Xu Y, Hashizume T, Taylor SL, Thummel KE, Shuhart MC. Reduced duodenal cytochrome P450 3A protein expression and catalytic activity in patients with cirrhosis. Clin Pharmacol Ther 2009; 85:387-93. [PMID: 19212316 DOI: 10.1038/clpt.2008.292] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
The small intestine and liver express high levels of cytochrome P450 3A (CYP3A), an enzyme subfamily that contributes significantly to drug metabolism. In patients with cirrhosis, reduced metabolism of drugs is typically attributed to decreased liver function, but it is unclear whether drug metabolism in the intestine is also compromised. In this study, we compared CYP3A protein expression and in vitro midazolam hydroxylation in duodenal mucosal biopsies from subjects with normal liver function (controls; n = 20) and subjects with various levels of severity of cirrhosis (n = 23). In samples from subjects with cirrhosis, duodenal CYP3A expression and total midazolam hydroxylation were lower by 47 and 34%, respectively, as compared with samples from controls. Greater decreases in CYP3A expression were seen in subjects with more severe cirrhosis. Therefore, patients with advanced cirrhosis may have greater drug exposure following oral dosing as a result of both impaired liver function and decreased intestinal CYP3A expression and activity.
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Affiliation(s)
- D J McConn
- Department of Pharmaceutics, University of Washington, Seattle, Washington, USA
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Ramsey SD, Sullivan SD, Malin J, Blough DK, Clarke L, McCune JS. Colony stimulating factor use and outcomes for breast, lung, and colorectal cancer patients in Washington State. J Clin Oncol 2007. [DOI: 10.1200/jco.2007.25.18_suppl.6616] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
6616 Background: Guidelines recommend colony stimulating factor (CSF) primary prophylaxis (PP) with chemotherapy if febrile neutropenia risk (FN) is =20%. Use of and outcomes for persons receiving CSF in clinical practice are relatively unknown. Methods: Using claims for Medicare and Medicaid enrollees linked to the Puget Sound SEER registry, breast (BCa), lung (LCa) and colorectal cancer (CRCa) patients diagnosed 2002–04 who received chemotherapy were categorized as: CSF at the start of chemotherapy (PP); other CSF; no CSF. Logistic regression was used to determine predictors of CSF PP and hospitalization for FN, controlling for cancer stage, age, sex, race, chemotherapy FN risk (from the National Comprehensive Cancer Network), radiation therapy, CSF use, health insurance, surgery =30 days of chemotherapy. Results: 364 BCa, 908 LCa, and 452 CRCa patients received chemotherapy. 43% of BCa, 30% of LCa, and 15% of CRCa patients received CSF. Only 9%, 6%, and 0.6% of patients initiated CSF as PP in the first cycle of chemotherapy. CSF use increased for all cancers, but most for BCa, (36% in 2002 to 70% in 2004); PP increased from 5% to 26%. Significant predictors (p<0.05) of PP were: BCa–local vs distant stage (OR 0.2), regional vs distant (OR 0.6), chemotherapy FN risk high vs low (OR 6.7); LCa–chemotherapy FN risk high vs low (OR 8.9), intermediate vs low (OR 6.3). FN incidence was 11%, 18% and 32% for BCa, CRCa, LCa, respectively. Significant predictors of FN were: BCa–nonwhite race (OR 2.7); LCa–surgery within 30 days (OR 1.7); CRCa–regional vs. distant (OR 0.4) and chemotherapy FN risk intermediate vs. low (OR 4.2). Conclusions: CSF use has increased significantly, but often in settings where efficacy is uncertain. Cancer type, stage and chemotherapy risk of FN influenced use of primary prophylaxis. Non-chemotherapy factors also appear to influence risk for FN. No significant financial relationships to disclose.
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Affiliation(s)
- S. D. Ramsey
- Fred Hutchinson Cancer Research Center, Seattle, WA; University of Washington, Seattle, WA; Amgen Inc, Thousand Oaks, CA; Cornerstone Systems Northwest, Lynden, WA; Seattle Cancer Care Alliance, Seattle, WA
| | - S. D. Sullivan
- Fred Hutchinson Cancer Research Center, Seattle, WA; University of Washington, Seattle, WA; Amgen Inc, Thousand Oaks, CA; Cornerstone Systems Northwest, Lynden, WA; Seattle Cancer Care Alliance, Seattle, WA
| | - J. Malin
- Fred Hutchinson Cancer Research Center, Seattle, WA; University of Washington, Seattle, WA; Amgen Inc, Thousand Oaks, CA; Cornerstone Systems Northwest, Lynden, WA; Seattle Cancer Care Alliance, Seattle, WA
| | - D. K. Blough
- Fred Hutchinson Cancer Research Center, Seattle, WA; University of Washington, Seattle, WA; Amgen Inc, Thousand Oaks, CA; Cornerstone Systems Northwest, Lynden, WA; Seattle Cancer Care Alliance, Seattle, WA
| | - L. Clarke
- Fred Hutchinson Cancer Research Center, Seattle, WA; University of Washington, Seattle, WA; Amgen Inc, Thousand Oaks, CA; Cornerstone Systems Northwest, Lynden, WA; Seattle Cancer Care Alliance, Seattle, WA
| | - J. S. McCune
- Fred Hutchinson Cancer Research Center, Seattle, WA; University of Washington, Seattle, WA; Amgen Inc, Thousand Oaks, CA; Cornerstone Systems Northwest, Lynden, WA; Seattle Cancer Care Alliance, Seattle, WA
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Shotorbani S, Miller L, Blough DK, Gardner J. Validation of a self-administered screening tool for selection of hormonal contraceptive methods. Contraception 2005. [DOI: 10.1016/j.contraception.2005.06.016] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Reed SD, Cramer SC, Blough DK, Meyer K, Jarvik JG. Treatment with tissue plasminogen activator and inpatient mortality rates for patients with ischemic stroke treated in community hospitals. Stroke 2001; 32:1832-40. [PMID: 11486113 DOI: 10.1161/01.str.32.8.1832] [Citation(s) in RCA: 160] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
BACKGROUND AND PURPOSE Most analyses of intravenous tissue plasminogen activator (IV tPA) use for acute stroke in routine practice have been limited by sample size and generally restricted to patients treated in large academic medical facilities. In the present study, we sought to estimate among community hospitals the use of IV tPA and to identify factors associated with the use of IV tPA and inpatient mortality. METHODS We evaluated a retrospective cohort of 23 058 patients with ischemic stroke from 137 community hospitals. RESULTS Three hundred sixty-two (1.6%) patients were treated with IV tPA, and 9.9% of those patients died during the hospitalization period. In 35.0% of the hospitals, no patients were treated with IV tPA, whereas 14.6% of hospitals treated approximately 3.0% with IV tPA. After control for multiple factors, younger patients, more severely ill patients (OR 2.02, 95% CI 1.36 to 3.01), and patients treated in rural hospitals (OR 1.80, 95% CI 0.99 to 3.26) were more likely to receive IV tPA, whereas black patients were less likely (OR 0.54, 95% CI 0.31 to 0.95). There also was a trend showing that women were less likely to receive IV tPA (OR 0.84, 95% CI 0.69 to 1.03). Factors associated with an increased odds of inpatient mortality included receipt of IV tPA among men (OR 2.81, 95% CI 1.72 to 4.58) and increased age. Black patients were 27% less likely to die during hospitalization (95% CI 0.60 to 0.90). CONCLUSIONS In this large, retrospective evaluation of community hospital practice, the use IV tPA and inpatient mortality rates among IV tPA-treated patients were consistent with those of other studies. The likelihood of receiving IV tPA varies by race, age, disease severity, and possibly gender. These factors may influence mortality rates.
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Affiliation(s)
- S D Reed
- Pharmaceutical Outcomes Research and Policy Program, School of Pharmacy, Department of Neurology, School of Medicine, University of Washington, Seattle, Washington, USA
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Abstract
BACKGROUND Accurate estimates of inpatient cost, length of stay (LOS), and mortality are necessary for the development of economic models to estimate the cost-effectiveness of stroke-related treatments. Estimates based on data from academic institutions may not be generalizable to community hospitals. In this study, the authors estimated inpatient costs, LOS, and in-hospital mortality for patients with subarachnoid hemorrhage (SAH), intracerebral hemorrhage (ICH), ischemic cerebral infarction (ICI), and TIA who were treated in community hospitals. METHODS The authors selected patients using International Classification of Diseases-9-Clinical Modification primary diagnosis codes from the HBSI EXPLORE database. They analyzed patient-level data and inpatient costs, derived from detailed utilization data, for all patients admitted to 137 community hospitals in 1998. Multivariate statistical techniques were used to examine patient-, hospital-, and outcome-related factors associated with inpatient costs. RESULTS Patients with SAH incurred the highest average cost ($23,777, n = 1,124), followed by patients with ICH ($10,241, n = 3,139), ICI ($5,837, n = 18,740), and TIA ($3,350, n = 7,861). Patient subgroups ranked in the same order for average LOS at 11.5 days for SAH, 7.5 days for ICH, 5.9 days for ICI, and 3.4 days for TIA. Almost one third of patients with SAH (29.0%) and ICH (33.1%) died during hospitalization, whereas 7.0% with ICI and 0.2% with TIA died. For each event, as patient age increased, average costs consistently decreased. Also, average costs were higher among patients treated in community teaching hospitals compared to community nonteaching hospitals for each cerebrovascular event (10 to 29%). CONCLUSIONS Inpatient costs, LOS, and mortality for patients with cerebrovascular disease are dependent on patient and hospital characteristics.
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Affiliation(s)
- S D Reed
- Pharmaceutical Outcomes Research & Policy Program, School of Pharmacy, University of Washington, Seattle, USA.
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McCune JS, Lindley C, Decker JL, Williamson KM, Meadowcroft AM, Graff D, Sawyer WT, Blough DK, Pieper JA. Lack of gender differences and large intrasubject variability in cytochrome P450 activity measured by phenotyping with dextromethorphan. J Clin Pharmacol 2001; 41:723-31. [PMID: 11452704 DOI: 10.1177/00912700122010627] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
Gender-based differences in cytochrome P450 (CYP) activity may occur due to endogenous hormonal fluctuations with the menstrual cycle, which are altered by oral contraceptives. This study assessed the average activity and within-subject variability in CYP3A4 and CYP2D6 in men, women taking Triphasil, and regularly menstruating women not receiving oral contraceptives. Thirty-three healthy volunteers participated in this 28-day pilot study (12 women receiving Triphasil) (OCs), 11 regularly menstruating women not on exogenous progesterone or estrogen (no OCs), and 10 men. CYP3A4 and CYP2D6 activities were phenotyped with dextromethorphan (DM) on study days 7, 14, 21, and 28 using urinary ratios of DM:3-methoxymorphinan (3MM) and DM:dextrorphan (DX), respectively. Serial blood concentrations of estrogen and progesterone and menstrual diaries were used to determine menstrual phase in both groups of women. Average urinary DM:3MM and DM:DX in the 28 extensive metabolizers of CYP2D6 did not differ between the three study populations (p = 0.86 and 0.93, respectively). Post hoc power analysis indicated that more than 1000 subjects would be needed for 80% power (alpha = 0.05) to detect a +/- 15% difference from the population mean in the urinary ratios of dextromethorphan and its metabolites 3MM and DX. Variability in CYP3A4 and CYP2D6 activity, characterized by intrasubject standard deviation, also did not differ. The varying doses of levonorgesterol and ethinyl estradiol in Triphasil, fluctuations in estrogen and progesterone, and menstrual phase did not influence CYP3A4 or CYP2D6 activity. It was concluded that CYP3A4 and CYP2D6 activity and intrasubject variability were not different in the three study populations, and thus a clinically important difference between men, women on Triphasil, and women not receiving oral contraceptives is unlikely. High inter- and intrasubject variability in DM:3MM and DM:DX were clearly demonstrated and limit the use of dextromethorphan to phenotype endogenous CYP3A4 and CYP2D6 activity.
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Abstract
OBJECTIVE To assess prevalence and risk factors for medication under- and overadherence in a two-week period following hospital discharge in adults > or = 65 years. DESIGN Prospective, cohort study. SETTING Three home healthcare agencies in Madison, Wisconsin, and surrounding vicinity. PARTICIPANTS One hundred forty-seven older participants taking three or more medications who were hospitalized for medical illness, received home nursing after discharge, and completed the two-week interview. MEASUREMENTS The main outcome measures were having at least one medication with less than 70% adherence (underadherence) and having at least one medication with more than 120% adherence (overadherence) based on pill counts. RESULTS Forty-five (30.6%) participants were underadherent and 27 (18.4%) participants were overadherent with at least one medication> In a multivariate model, underadherence was predicted by poor cognition (OR 2.5; 95% CI 1.02 to 6.10) and higher medication use (OR 1.16; 95% CI 1.03 to 1.31, for each 1-unit increase in number of medications). Both poor cognition and low education were significantly associated with overadherence in univariate analysis; however, neither variable was significant once included in the multivariate model. CONCLUSIONS Under- and overadherence to medications is common after hospital discharge. Poor cognition and a greater number of medications were associated with underadherence. Poor and lower education were markers for overadherence; however, further study is needed to determined whether these are independent predictors. Patients who have impaired cognition or are taking a greater number of medications after hospitalization may benefit from targeted interventions to monitor and improve medication compliance.
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Affiliation(s)
- S L Gray
- School of Pharmacy, University of Washington, Seattle 98195-7630, USA.
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Abstract
OBJECTIVE To assess incidence, healthcare consequences, and identify risk factors for adverse drug events (ADEs) in elderly patients receiving home health services during the month following hospital discharge. METHOD This was a prospective cohort study of three home health agencies in Madison, Wisconsin, and its surrounding area. The sample consisted of 256 participants aged > or =65 years who were hospitalized for medical illness, received home nursing after discharge, and completed the one-month interview. The main outcome measure was self-reported ADEs (possible, probable, or definite) during the month following hospital discharge. RESULTS Incidence of ADEs was 20%. Fifty-two participants (20.3%) reported 64 ADEs: 23 possible, 37 probable, and four definite. The most common ADEs involved the gastrointestinal tract (31.3%) and the central nervous system (31.3%). Of 53 ADEs reported to providers, 59% of the drugs were discontinued or altered. One ADE resulted in hospitalization. In logistic regression, female gender (OR = 2.26; 95% CI 1.06 to 4.77) and the interaction between number of new medications and cognition were significantly associated with ADEs. The risk of an event increased with the number of new medications at discharge; however, risk was elevated primarily for participants with lower cognition. CONCLUSIONS ADEs were common during the month following hospital discharge, were more frequent in women, and often resulted in medication changes. Individuals at particular risk were those with lower cognition who were discharged with several new medications.
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Affiliation(s)
- S L Gray
- School of Pharmacy, University of Washington, Seattle 98195, USA.
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Abstract
Obstructive sleep apnea is an under-diagnosed, but common disorder with serious adverse consequences. Cost data from the year prior to the diagnosis of sleep-disordered breathing in a consecutive series of 238 cases were used to estimate the potential medical cost of undiagnosed sleep apnea and to determine the relationship between the severity of sleep-disordered breathing and the magnitude of medical costs. Among cases, mean annual medical cost prior to diagnosis was $2720 versus $1384 for age and gender matched controls (p<0.01). Regression analysis showed that the reciprocal of the apnea hypopnea index among cases was significantly related to log-transformed annual medical costs after adjusting for age, gender, and body mass index (p<0.05). We conclude that patients with undiagnosed sleep apnea had considerably higher medical costs than age and sex matched individuals and that the severity of sleep-disordered breathing was associated with the magnitude of medical costs. Using available data on the prevalence of undiagnosed moderate to severe sleep apnea in middle-aged adults, we estimate that untreated sleep apnea may cause $3.4 billion in additional medical costs in the U.S. Whether medical cost savings occur with treatment of sleep apnea remains to be determined.
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Affiliation(s)
- V Kapur
- Department of Medicine, University of Washington, Seattle 98195, USA
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Abstract
Traditionally, linear regression has been the technique of choice for predicting medical risk. This paper presents a new approach to modeling the second part of two-part models utilizing extensions of the generalized linear model. The primary method of estimation for this model is maximum likelihood. This method as well as the generalizations quasi-likelihood and extended quasi-likelihood are discussed. An example using medical expense data from Washington State employees is used to illustrate the methods. The model includes demographic variables as well as an Ambulatory. Care Group variable to account for prior health status.
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Affiliation(s)
- D K Blough
- University of Washington, Seattle, WA, USA
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