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NKF 2007 Spring Clinical Meetings Abstracts
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EARLY DETECTION OF ARTERIOVENOUS FISTULA STENOSIS BY DOPPLER ULTRASONOGRAPHY (DUS) Shikha Mehta, Mark E. Lockhart, Rachel Oser, Michelle L. Robbin, Michael Allon. The University of Alabama at Birmingham, Birmingham, AL, USA A substantial proportion (20-50%) of new dialysis fistulas are not usable for dialysis due to failure to mature. Early stenosis near the anastomosis or in the draining vein occurs commonly in immature fistulas, and correction of the stenosis may promote fistula maturation. Stenosis may be detected by a fistulogram (invasive and expensive) or by DUS (noninvasive and cheap). However, little is known about the accuracy of DUS in predicting stenosis in clinically immature fistulas. We queried a prospective, computerized vascular access database to identify 59 patients undergoing DUS within 2 months of fistula creation AND a fistulogram within 2 months following the DUS. Their mean age was 58 years, 56% were male, 83% were black, 58% had diabetes, 52% had an upper arm fistula, and 34% had clinical signs of fistula stenosis. A >50% stenosis on fistulogram was deemed hemodynamically significant. DUS was considered suspicious for stenosis if: (1) Systolic Velocity Ratio (SVR) >3:1 within 4 cm of the anastamosis or >2:1 in the outflow vein, OR (2) Peak Systolic Velocity (PSV) >4 m/sec at the stenosis, OR (3) access flow < 400 ml/minute. Of 46 patients with significant stenosis by fistulogram, 41 had a positive DUS (sensitivity 89%), and 5 had negative DUS. Of 51 patients with positive DUS, 41 had stenosis by fistulogram (positive predictive value 80%). The overall accuracy of DUS was 74.5%. We conclude that DUS is a sensitive, non-invasive tool to screen for significant stenosis in clinically immature fistulas.
ACUTE KIDNEY INJURY IN A PATIENT WITH MASSIVE ASCITES AND INCREASED INTRA-ABDOMINAL PRESSURE Zurab Mepharishvilli, Robert Gayner, Joseph Jacobs, Richard Snyder, Easton Hospital/Drexel University College of Medicine, Easton, PA. Acute Kidney Injury (AKI) in the setting of liver failure and ascites is often thought to be secondary to either pre-renal azotemia, ATN, or hepatorenal syndrome. The hemodynamics of increased intraabdominal pressure (IAP) and abdominal compartment syndrome have gained significant attention in the trauma and critical care literature. A MEDLINE search yielded only a few cases involving IAP in patients with liver failure and massive ascites. We report the case of an 82-year-old male, with a past medical history of cirrhosis and recurrent ascites, admitted to the ICU due to acute respiratory distress and anuria. The patient had AKI: Labs showed a BUN of 77 mg/dl, creatinine of 4.4 mg/dl, and K of 7.5meq/l. The abdominal exam demonstrated massive ascites, which was confirmed by ultrasound. Intravesicular bladder pressure was 32 mmHg. Paracentesis was performed, and 10 liters of fluid was drained. The patient was started on hemodialysis. Within 24 hours of paracentesis his kidney function had drastically improved, with a significant increase in urine output. Dialysis was discontinued and a Tenckhoff catheter was placed in the abdominal cavity for ascites drainage. Many mechanisms have been proposed to explain the effects of IAP on renal function. An IAP above 30 mm Hg is related to significant anuria. Renal derangements involve a reduction in effective renal blood flow, corticomedullary shunting of renal plasma flow, reduction of GFR, water reabsorbtion, and increasing renal venous pressure. We believe that IAP with altered renal hemodynamics should be considered in the differential diagnosis of AKI in a patient with cirrhosis and ascites, especially in those patients with tense ascites.
A61
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DRUG UTILIZATION AND COST CONSIDERATIONS OF ERYTHROPOIETIC STIMULATING AGENTS IN CHRONIC KIDNEY DISEASE PATIENTS NOT RECEIVING DIALYSIS Samir Mody2, Francis Vekeman1, Antoine Gosselin1, Brahim Bookhart2, R. Scott McKenzie2, Patrick Lefebvre3 1 Groupe d’analyse, Ltée, Montréal, Québec, Canada; 2Ortho Biotech Clinical Affairs, LLC, Bridgewater, NJ, USA; 3Analysis Group, Inc., Boston, MA, USA This analysis aimed to examine recent epoetin alfa (EPO) and darbepoetin alfa (DARB) treatment patterns and corresponding drug costs in CKD patients not receiving dialysis. A medical claims analysis was conducted from 1/2004 through 12/2005 using the PharMetrics Patient-Centric database. Patients included in the study were 18 years, had 1 claim for CKD, and were newly initiated on EPO or DARB and received 2 doses. Patients diagnosed with cancer or receiving chemotherapy were excluded. The weighted mean weekly dose was scaled based on the duration of therapy. September 2006 wholesale acquisition costs were used to calculate drug costs (EPO $12.17/1,000 Units; DARB $4.446/mcg). The study population consisted of 187 patients who received EPO and 129 who received DARB. EPO patients were significantly older (mean age: EPO 59 years, DARB 53 years, p<.05). The proportion of women was similar between the two groups (EPO: 55%; DARB: 49%). Extended dosing frequency (defined as every 2 weeks or greater, ≥Q2W) during treatment was observed in the majority of patients in both groups (EPO – QW: 39%, Q2W: 47%, Q3W: 8%, ≥Q4W: 6%; DARB – QW: 10%, Q2W: 53%, Q3W: 19%, ≥Q4W: 18%). The weighted mean weekly dose was 13,563 ± 10,245 Units for EPO and 55 ± 36 mcg for DARB. Based on these doses, mean weekly drug cost was 48% higher in the DARB group (EPO $165; DARB $245; p<.0001). These findings, based on actual clinical practice, are similar to those reported in previously published observational studies.
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COMPARISON OF EMPLOYER COST AMONG EMPLOYEES WITH ANEMIA OF CHRONIC KIDNEY DISEASE, HEALTHY EMPLOYEES, AND THOSE WITH CHRONIC OBSTRUCTIVE PULMONARY DISEASE OR RHEUMATOID ARTHRITIS Frank Papatheofanis1, Namrita Chawla2, Brahim K. Bookhart3, Erik Muser3, Catherine Tak Piech3 1 UCSD, San Diego, CA, USA; 2Aequitas, San Diego, CA, USA; 3 Ortho Biotech Clinical Affairs, LLC, Bridgewater, NJ, USA Despite the debilitating nature of anemia of CKD, few studies have estimated its cost to employers or compared those costs to other common chronic conditions. This analysis compared the employer cost burden for employees of a major U.S. manufacturer who had either anemia of CKD, were healthy, or had COPD or RA. Data were reported for a span of 15 months and mean direct and indirect costs were calculated for each cohort. Direct costs included medical and pharmacy costs, while indirect costs included absenteeism (work days lost) and presenteeism (decrease in productivity during work time due to illness). Presenteeism was measured by SKU (stock keeping units), a numeric identifier used in tracking parts and specific product inventory. This number is used as a proxy for productivity in settings where employees install the relevant SKU. Independent t-tests were conducted to identify significant cost differences between cohorts and a linear regression was used to determine the effect of each disease on cost. Anemia of CKD was shown to have a significant impact on direct and indirect costs. Healthy employees and employees with COPD or RA had 38.1-60.0% lower pharmacy costs than those with anemia of CKD. Healthy employees’ medical costs were 78.1% lower than the anemic-CKD cohort’s costs, however, medical costs were similar between patients with anemia of CKD and RA or COPD. Healthy employees and those with RA or COPD were more productive than those with anemia of CKD; working 29.673.5% more days and producing 57.3-107.7% more SKU. These findings indicate that anemia of CKD resulted in more work days lost, lower productivity levels and higher healthcare costs per patient than COPD or RA.
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EARLY DETECTION OF ARTERIOVENOUS FISTULA STENOSIS BY DOPPLER ULTRASONOGRAPHY (DUS) Shikha Mehta, Mark E. Lockhart, Rachel Oser, Michelle L. Robbin, Michael Allon. The University of Alabama at Birmingham, Birmingham, AL, USA A substantial proportion (20-50%) of new dialysis fistulas are not usable for dialysis due to failure to mature. Early stenosis near the anastomosis or in the draining vein occurs commonly in immature fistulas, and correction of the stenosis may promote fistula maturation. Stenosis may be detected by a fistulogram (invasive and expensive) or by DUS (noninvasive and cheap). However, little is known about the accuracy of DUS in predicting stenosis in clinically immature fistulas. We queried a prospective, computerized vascular access database to identify 59 patients undergoing DUS within 2 months of fistula creation AND a fistulogram within 2 months following the DUS. Their mean age was 58 years, 56% were male, 83% were black, 58% had diabetes, 52% had an upper arm fistula, and 34% had clinical signs of fistula stenosis. A >50% stenosis on fistulogram was deemed hemodynamically significant. DUS was considered suspicious for stenosis if: (1) Systolic Velocity Ratio (SVR) >3:1 within 4 cm of the anastamosis or >2:1 in the outflow vein, OR (2) Peak Systolic Velocity (PSV) >4 m/sec at the stenosis, OR (3) access flow < 400 ml/minute. Of 46 patients with significant stenosis by fistulogram, 41 had a positive DUS (sensitivity 89%), and 5 had negative DUS. Of 51 patients with positive DUS, 41 had stenosis by fistulogram (positive predictive value 80%). The overall accuracy of DUS was 74.5%. We conclude that DUS is a sensitive, non-invasive tool to screen for significant stenosis in clinically immature fistulas.
ACUTE KIDNEY INJURY IN A PATIENT WITH MASSIVE ASCITES AND INCREASED INTRA-ABDOMINAL PRESSURE Zurab Mepharishvilli, Robert Gayner, Joseph Jacobs, Richard Snyder, Easton Hospital/Drexel University College of Medicine, Easton, PA. Acute Kidney Injury (AKI) in the setting of liver failure and ascites is often thought to be secondary to either pre-renal azotemia, ATN, or hepatorenal syndrome. The hemodynamics of increased intraabdominal pressure (IAP) and abdominal compartment syndrome have gained significant attention in the trauma and critical care literature. A MEDLINE search yielded only a few cases involving IAP in patients with liver failure and massive ascites. We report the case of an 82-year-old male, with a past medical history of cirrhosis and recurrent ascites, admitted to the ICU due to acute respiratory distress and anuria. The patient had AKI: Labs showed a BUN of 77 mg/dl, creatinine of 4.4 mg/dl, and K of 7.5meq/l. The abdominal exam demonstrated massive ascites, which was confirmed by ultrasound. Intravesicular bladder pressure was 32 mmHg. Paracentesis was performed, and 10 liters of fluid was drained. The patient was started on hemodialysis. Within 24 hours of paracentesis his kidney function had drastically improved, with a significant increase in urine output. Dialysis was discontinued and a Tenckhoff catheter was placed in the abdominal cavity for ascites drainage. Many mechanisms have been proposed to explain the effects of IAP on renal function. An IAP above 30 mm Hg is related to significant anuria. Renal derangements involve a reduction in effective renal blood flow, corticomedullary shunting of renal plasma flow, reduction of GFR, water reabsorbtion, and increasing renal venous pressure. We believe that IAP with altered renal hemodynamics should be considered in the differential diagnosis of AKI in a patient with cirrhosis and ascites, especially in those patients with tense ascites.
A61
147
DRUG UTILIZATION AND COST CONSIDERATIONS OF ERYTHROPOIETIC STIMULATING AGENTS IN CHRONIC KIDNEY DISEASE PATIENTS NOT RECEIVING DIALYSIS Samir Mody2, Francis Vekeman1, Antoine Gosselin1, Brahim Bookhart2, R. Scott McKenzie2, Patrick Lefebvre3 1 Groupe d’analyse, Ltée, Montréal, Québec, Canada; 2Ortho Biotech Clinical Affairs, LLC, Bridgewater, NJ, USA; 3Analysis Group, Inc., Boston, MA, USA This analysis aimed to examine recent epoetin alfa (EPO) and darbepoetin alfa (DARB) treatment patterns and corresponding drug costs in CKD patients not receiving dialysis. A medical claims analysis was conducted from 1/2004 through 12/2005 using the PharMetrics Patient-Centric database. Patients included in the study were 18 years, had 1 claim for CKD, and were newly initiated on EPO or DARB and received 2 doses. Patients diagnosed with cancer or receiving chemotherapy were excluded. The weighted mean weekly dose was scaled based on the duration of therapy. September 2006 wholesale acquisition costs were used to calculate drug costs (EPO $12.17/1,000 Units; DARB $4.446/mcg). The study population consisted of 187 patients who received EPO and 129 who received DARB. EPO patients were significantly older (mean age: EPO 59 years, DARB 53 years, p<.05). The proportion of women was similar between the two groups (EPO: 55%; DARB: 49%). Extended dosing frequency (defined as every 2 weeks or greater, ≥Q2W) during treatment was observed in the majority of patients in both groups (EPO – QW: 39%, Q2W: 47%, Q3W: 8%, ≥Q4W: 6%; DARB – QW: 10%, Q2W: 53%, Q3W: 19%, ≥Q4W: 18%). The weighted mean weekly dose was 13,563 ± 10,245 Units for EPO and 55 ± 36 mcg for DARB. Based on these doses, mean weekly drug cost was 48% higher in the DARB group (EPO $165; DARB $245; p<.0001). These findings, based on actual clinical practice, are similar to those reported in previously published observational studies.
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COMPARISON OF EMPLOYER COST AMONG EMPLOYEES WITH ANEMIA OF CHRONIC KIDNEY DISEASE, HEALTHY EMPLOYEES, AND THOSE WITH CHRONIC OBSTRUCTIVE PULMONARY DISEASE OR RHEUMATOID ARTHRITIS Frank Papatheofanis1, Namrita Chawla2, Brahim K. Bookhart3, Erik Muser3, Catherine Tak Piech3 1 UCSD, San Diego, CA, USA; 2Aequitas, San Diego, CA, USA; 3 Ortho Biotech Clinical Affairs, LLC, Bridgewater, NJ, USA Despite the debilitating nature of anemia of CKD, few studies have estimated its cost to employers or compared those costs to other common chronic conditions. This analysis compared the employer cost burden for employees of a major U.S. manufacturer who had either anemia of CKD, were healthy, or had COPD or RA. Data were reported for a span of 15 months and mean direct and indirect costs were calculated for each cohort. Direct costs included medical and pharmacy costs, while indirect costs included absenteeism (work days lost) and presenteeism (decrease in productivity during work time due to illness). Presenteeism was measured by SKU (stock keeping units), a numeric identifier used in tracking parts and specific product inventory. This number is used as a proxy for productivity in settings where employees install the relevant SKU. Independent t-tests were conducted to identify significant cost differences between cohorts and a linear regression was used to determine the effect of each disease on cost. Anemia of CKD was shown to have a significant impact on direct and indirect costs. Healthy employees and employees with COPD or RA had 38.1-60.0% lower pharmacy costs than those with anemia of CKD. Healthy employees’ medical costs were 78.1% lower than the anemic-CKD cohort’s costs, however, medical costs were similar between patients with anemia of CKD and RA or COPD. Healthy employees and those with RA or COPD were more productive than those with anemia of CKD; working 29.673.5% more days and producing 57.3-107.7% more SKU. These findings indicate that anemia of CKD resulted in more work days lost, lower productivity levels and higher healthcare costs per patient than COPD or RA.