Cost comparison of tinzaparin versus enoxaparin as deep venous thrombosis prophylaxis in spinal cord injury: preliminary data.

Thromboembolic events are major causes of morbidity and mortality in patients with spinal cord injuries. Low molecular weight heparins are recommended as prophylaxis against such events. The purpose of the current study was to perform a cost analysis of tinzaparin versus enoxaparin using published efficacy and safety data as deep vein thrombosis and pulmonary embolism prophylaxis in this population. All published English language articles evaluating either tinzaparin or enoxaparin as pharmacoprophylaxis in spinal cord-injured patients were identified. Data from these studies were subjected to cost-effectiveness analyses followed by sensitivity analyses to determine which agent is the most cost-effective in these patients. Results demonstrated that tinzaparin 3500 U daily and enoxaparin 30 mg every 12 h are both cost-effective agents for thromboembolism prophylaxis in patients with spinal cord injuries.

Three Michaelis-Menten pharmacokinetic dosing methods compared with physician dosing of phenytoin in an outpatient neurology practice.

We compared predicted phenytoin serum concentrations using three Michaelis-Menten pharmacokinetic dosing methods with actual concentrations obtained from physician dosing in an outpatient neurology practice. Method 1 used population estimates for the Michaelis-Menten constant (Km) and maximum velocity (Vmax), method 2 used one dose and serum concentration pair to determine Vmax, and method 3 used two dose-concentration pairs to determine both Km and Vmax. In addition, physician doses were compared with pharmacokinetically calculated doses. Records of patients who received at least two phenytoin doses followed by two serum concentration determinations were reviewed. Data on age, gender, weight, physician doses, and resultant serum concentrations were collected. Pearson's correlation coefficient was used to compare physician maintenance doses with pharmacokinetically calculated predicted doses, whereas actual and predicted serum concentration data were used to determine precision and bias associated with each of the three methods. Actual serum concentrations fell into therapeutic range more frequently than predicted values in all but one comparison (method 3). Predicted and actual phenytoin doses were significantly correlated only with method 2. Only one of the three Michaelis-Menten pharmacokinetic dosing methods evaluated (method 3) was more predictive than physician phenytoin dosing.

Improved health-related quality of life with SSRIs and other antidepressants.

STUDY OBJECTIVE: To document the health-related quality of life (HRQOL) of depressed patients receiving antidepressant drugs. DESIGN: Cross-sectional study. SETTING: Community pharmacy-based setting. PATIENTS: Fifty-seven depressed patients. INTERVENTION: Independent pharmacist members of the Community Pharmacists Research Network in Georgia administered the Medical Outcomes Study 36-Item Short-Form Health Survey (SF-36) to subjects. MEASUREMENTS AND MAIN RESULTS: Sixty-one percent of patients were treated with a selective serotonin reuptake inhibitor (SSRI) and 38.6% were treated with a non-SSRI. Those receiving SSRIs scored higher on the mean physical (PCS) and mental (MCS) health summary scores of the SF-36 than those not receiving the drugs. No significant differences were seen in PCS or MCS scores of men and women. CONCLUSION: Community pharmacists documented better HRQOL in patients receiving SSRIs than in those given other antidepressants.

Achievement of anticoagulation by using a weight-based heparin dosing protocol for obese and nonobese patients.

The need for different heparin dosing protocols for obese and nonobese patients was studied. A chart review was performed for all patients who received heparin over an eight-month period at an acute care hospital. Data collected included age, sex, height, actual body weight (ABW), ideal body weight (IBW), initial activated partial thromboplastin time (aPTT), initial heparin bolus dose, initial heparin i.v. infusion rate, time to initial targeted aPTT, and final infusion rate. Forty patients met criteria for inclusion: 20 obese patients (greater than 30% over IBW) and 20 nonobese patients (less than 20% over IBW). Mean +/- S.D. initial heparin infusion rates for the obese and nonobese groups were 14.44+/-1.29 and 15.04+/-0.42 units/kg/hr, respectively. Times to targeted aPTT for obese and nonobese patients were 25.86+/-12.83 and 25.18+/-14.76 hours, respectively; mean final infusion rates were 12.94+/-2.56 and 12.36+/-2.54 units/kg/hr; and percent changes from initial to final infusion rates were 11.84% and 17.76%. There were no significant differences in initial or final infusion rates or time to targeted aPTT between the two groups. It is appropriate to use ABW in a weight-based heparin dosing protocol for obese patients.

Venous thrombosis after acute spinal cord injury: cost analysis of prophylaxis guidelines.

OBJECTIVE: Venous thrombosis and pulmonary embolisms are major complications associated with acute spinal cord injury. The purpose of this study was to perform a cost analysis on the two pharmacoprophylaxis regimens suggested for deep vein thrombosis prophylaxis in this population. METHODS: Efficacy and safety data were obtained from the literature. RESULTS: Results of the cost analysis demonstrates that adjusted dose unfractionated heparin produces a cost savings over enoxaparin at 30 mg every 12 hr. CONCLUSION: Further studies are needed to determine the most cost-effective therapy for preventing deep vein thrombi in this population.

Renal transplant patient compliance with free immunosuppressive medications.

BACKGROUND: Noncompliance with immunosuppressive medications after renal transplantation is believed to be a major cause of allograft rejection and graft loss, with the impressive costs of these agents considered a significant reason for noncompliance. Our purpose was to determine the compliance rates of renal transplant patients who received their immunosuppressant therapy free of charge and evaluate their patterns of compliance. METHODS: All patients who received a renal transplant and received their immunosuppressant medications at our institution for their first year posttransplant were included in the study. Compliance rate was calculated and serum immunosuppressant concentrations were obtained to validate compliance assessments. RESULTS: Eighteen patients were included in the study. Approximately 48% of noncompliant patients were found to have subtarget drug concentrations, although only 14% of compliant patients had subtarget levels (chi2=12.9, P<0.001). At 5 months posttransplant, 95% of the patients remained compliant; however, by 12 months posttransplant, only 48% of the patients remained compliant. The mean time to the first noncompliant month was 9.8 months (95% confidence intervals=8.60-11.0). CONCLUSIONS: Patients who received their immunosuppressants free of charge were generally compliant within their first year of transplantation, however, compliance tended to decrease over time. This suggests that drug cost alone does not explain noncompliant behavior. Intensive efforts to increase medication compliance before month 8 posttransplantation should be implemented.

Cost-benefit analysis of a clinical pharmacist-managed medication assistance program in a renal transplant clinic.

UNLABELLED: Medicare pays for 80% of the cost of immunosuppressant agents needed within the first 3 years of solid organ transplantation; however, many patients cannot afford the remaining 20%. Furthermore, many patients who are beyond 3 years post-transplantation and have prescription coverage cannot afford the co-payment for these medications. Other patients may not be able to afford their medications due to limited or no insurance coverage. The Medical College of Georgia (MCG) has been giving immunosuppressant medications to renal transplant patients if they cannot afford to pay for them. To assist MCG with drug cost for medications and maintain quality care for renal transplant patients, a clinical pharmacist-managed medication assistance program was implemented to procure immunosuppressants from pharmaceutical manufacturers. METHODS: All patients enrolled in medication assistance programs from 1 January 1998 through 31 December 1998 were included in this analysis. Medication acquisition costs with and without Medicare reimbursement and the cost of implementing the clinical pharmacist-managed medication assistance program were used to determine the value of implementing this service. RESULTS: Sixty-one patients were enrolled in manufacturers' assistance programs and a net cost avoidance of $124,793 was realized for the year of the program (benefit-to-cost ratio of 7.5:1). Assuming that the hospital collected the maximum amount allowed for patients receiving Medicare benefits, a cost avoidance of $69,233 was calculated (benefit-to-cost ratio of 4.16:1). CONCLUSIONS: A clinical pharmacist-managed medication assistance program in a renal transplant clinic produced substantial cost savings over this 1-year study period. For each dollar spent in pharmacist's time, a minimum of $4 was returned to the institution.

Cost effectiveness of deep venous thrombosis prophylaxis after hip fracture.

Patients undergoing hip fracture repair are at significant risk for deep vein thrombosis and pulmonary embolism in the postoperative period without appropriate prophylaxis. Agents available in the United States that have undergone clinical trials as pharmacoprophylaxis for this indication include warfarin, dalteparin, and danaparoid. Safety and efficacy data from these trials were used to determine the most cost-effective agent for routine deep vein thrombosis prophylaxis in patients with hip fractures. Incremental cost-effectiveness ratio calculations demonstrate that warfarin dosed to an international normalized ratio of 2-2.7 is currently the most cost-effective agent in these patients.

Cost effectiveness of outpatient anticoagulant prophylaxis after total hip arthroplasty.

Guidelines for deep venous thrombosis (DVT) and pulmonary embolism (PE) prophylaxis have been developed for patients undergoing total hip arthroplasty (THA). Studies suggest that risk for developing these complications may exist for as long as 3 months following surgery. Cost-effectiveness analyses were performed on three pharmacoprophylaxis regimens administered over a 30-day period using literature-reported values for incidences of DVT and PE in patients postdischarge following THA. A cost savings of $21,466.89 will occur for each thromboembolic event avoided if low-dose warfarin daily is used routinely compared to enoxaparin 40 mg daily. Additionally, a cost savings of $18,618.10 is experienced if enoxaparin 40 mg daily for 4 days plus low-dose warfarin daily is administered versus enoxaparin 40 mg daily. Clinicians may choose to continue prophylaxis postdischarge with enoxaparin 40 mg daily for 4 days in combination with warfarin for 30 days in these patients until results of more definitive studies become available.

Formulary management of low molecular weight heparins.

Low molecular weight heparins (LMWHs) are increasingly being utilised as anticoagulants in healthcare settings. These agents offer several advantages over standard unfractionated heparin. Indications for LMWHs include deep vein thrombosis and pulmonary embolism prophylaxis, deep vein thrombosis treatment, use in coronary procedures associated with a high risk for bleeding, and in acute coronary syndromes. Prior to being added to formularies, LMWHs should be evaluated for efficacy, safety and economic benefits over other anticoagulants. Institutions should be prepared to conduct their own economic assessments in the absence of readily available studies. There is clear evidence that LMWHs are cost saving or are at least cost effective as thromboprophylactic agents in major orthopaedic surgery. The economic benefits of LMWHs in other surgical situations is less clear. Consistent evidence from several countries indicate that LMWHs are cost saving as anticoagulants for the initial treatment of DVT. Further studies are needed to evaluate the efficacy, safety and economics of LMWHs in other conditions besides hip and knee arthroplasty and general surgery.

Deep venous thrombosis prophylaxis in trauma: cost analysis.

Deep vein thrombosis and pulmonary embolism are major risks in patients experiencing major trauma. Currently, the American College of Chest Physicians recommends low molecular weight heparin as prophylaxis in trauma patients with identifiable risk factors in the absence of contraindications. Enoxaparin is the only low molecular weight heparin available in the US that has been evaluated to date in this indication. The purpose of this study was to perform incremental cost-effectiveness ratio calculations for enoxaparin versus no prophylaxis as thromboembolic prophylaxis in trauma patients. These calculations demonstrate that a cost of $279.43 would be incurred for each thromboembolic event avoided if enoxaparin 30 mg every 12 h were routinely used as prophylaxis in this population, compared with no prophylaxis. Sensitivity analyses demonstrate that if the incidence of proximal vein thrombosis in patients prophylaxed with enoxaparin approached 1.8%, if the actual rate of these thrombi exceeded 19.4% in untreated patients, or if the cost of the drug was decreased to $15.25 per dose, a cost saving would be experienced in routine prophylaxis with this agent.

Cost effectiveness of danaparoid compared with enoxaparin as deep vein thrombosis prophylaxis after hip replacement surgery.

Guidelines for prophylaxis of deep vein thrombosis (DVT) after hip replacement surgery suggest the use of twice-daily low-molecular-weight heparin as one treatment option. Danaparoid, a low-molecular-weight heparinoid, and once-daily enoxaparin are recently released dosage forms that have been evaluated as pharmacoprophylaxis for DVT after hip replacement surgery. Incremental cost-effectiveness ratio calculations using published efficacy and safety data suggest that enoxaparin (40 mg) daily is the more cost effective of these two agents as routine prophylaxis after hip replacement surgery.

Persistence with estrogen therapy in a postmenopausal Medicaid population.

We evaluated rates of persistence with estrogen replacement therapy in postmenopausal Georgia Medicaid recipients adjusted for age and race. Data files for 1992-1994 were examined to estimate 3-year conditional survival probabilities using the Kaplan-Meier model, and 3800 subjects were identified. Over 54% of women remained compliant over 29 months, and 17% continued therapy for the entire 35 months of observation. Kaplan-Meier predictors indicated that white women have a 70% chance of being compliant for 3 years, whereas black women have a 60% chance. Monthly discontinuation rates ranged from 1-1.5% after the second month of therapy. Younger, white women were the most likely to maintain and comply with therapy.