A study of drug utilisation and cost of treatment in patients hospitalised with unstable angina

OBJECTIVE

The current study was designed to investigate drug utilisation in the management of unstable angina in India and to calculate the costs incurred by patients in the treatment of a single episode of unstable angina.

METHODS

We conducted a prescription survey to examine the use of antianginal drugs in patients with unstable angina in a tertiary care Indian hospital. The use of concurrent medications such as antidiabetic, antihypertensive and lipid-lowering agents was also examined. Data on the cost of treatment, investigations, income, and family size were collected from the case histories or direct interviews with the patients/relatives.

RESULTS

A total of 336 consecutive prescriptions were evaluated. Aspirin was the most frequently prescribed drug (98%) followed by nitroglycerin infusion (90%) and enoxaparin (52%). One of the heparins was used by 89% of all patients and beta-blockers by up to 62% of the patients. Besides antianginals, antihypertensive (49%) and antidiabetic (16%) drugs were commonly coadministered. The mean (+/- SD) cost of treatment of a single episode of unstable angina in the hospital was US $494 (+/- 271) against an annual per capita income of US $245. The mean (+/- SD) cost incurred by the patients due to drugs alone during the hospital stay was US $70 (+/- 18) and enoxaparin accounted for 60% of the expenditure due to drugs.

CONCLUSIONS

The results of our study show that low-molecular-weight heparin, enoxaparin, is replacing unfractionated heparin in the treatment of unstable angina. In view of the use of costly new drugs, there is an urgent need for carrying out pharmacoeconomic analysis in developing countries as the treatment of a single episode of unstable angina imparts a considerable economic burden on the patient.

Transdermal nitroglycerin for the prevention of intravenous infusion failure due to phlebitis and extravasation

OBJECTIVE

To evaluate the clinical use of transdermal nitroglycerin for the prevention of intravenous infusion failures due to phlebitis or extravasation.

DATA SOURCES

Clinical literature was accessed through a MEDLINE search (1966-May 2000). Key search terms included nitroglycerin, transdermal, phlebitis, extravasation, intravenous, and infusion.

DATA SYNTHESIS

Common and serious consequences of intravenous therapy include the occurrence of postinfusion phlebitis and failure to maintain intravenous therapy due to intravenous fluid extravasation. Transdermal application of nitroglycerin has been evaluated as a treatment and preventive method for intravenous infusion failures related to phlebitis or extravasation. An evaluation of studies focusing on transdermal nitroglycerin in the prevention of infusion failures due to phlebitis or extravasation was conducted.

CONCLUSIONS

Use of transdermal nitroglycerin as a prophylactic measure for intravenous infusion failures is a therapeutic option for patients requiring long-term intravenous therapy (i.e., > 50 h).

PGE(1) treatment of severe intermittent claudication (short-term versus long-term, associated with exercise)--efficacy and costs in a 20-week, randomized trial

The efficacy, safety, and cost of prostaglandin E1 (PGE1) in the treatment of severe intermittent claudication was studied comparing a long-term treatment protocol (LTP) with a short-term treatment protocol (STP) in a randomized 20-week study. The study included 980 patients (883 completed the study) with an average total walking distance of 85.5 +/-10 m (range 22-119). Phase 1 was a 2-week run-in phase (no treatment) for both protocols. In LTP, phase 2 was the main treatment phase. In the LTP, treatment was performed with 2-hour infusions (60 microg PGE1, 5 days each week for 4 weeks. In phase 3 (4-week interval period) PGE1 was administered twice a week (same dosage). In phase 4 (monitoring lasting 3 months, from week 9 to 20) no drugs were used. In STP phase 2 treatment was performed in 2 days by a 2-hour infusion (first day: morning 20 microg, afternoon 40 microg; second day morning and afternoon 60 microg). The reduced dosage was used only at the first cycle (week 0) to evaluate tolerability or side effects. Full dosage (60 microg bid) was used for all other cycles. The same cycle was repeated at the beginning of weeks 4, 8, and 12. The observation period was between weeks 12 and 20. A treadmill test was performed at inclusion, at the beginning of each phase, and at the end of 20th week. A similar progressive physical training plan (based on walking) and a reduction in risk factors levels plan was used in both groups. Intention-to-treat analysis indicated an increase in walking distance, which improved at 4 weeks and at 20 weeks in the STP more than in the LTP group. At 4 weeks the variation (increase) in pain-free walking (PFWD) was 167.8% (of the initial value) in the LTP group and 185% in the STP group (p<0.05). At 4 weeks the variation (increase) in total walking distance (TWD) was 227.6% of the initial value in the LTP group and 289% in the STP group (p<0.05). At 20 weeks the increase in PFWD was 496% of the initial value in the LTP group vs 643% in the STP group (147% difference; p<0.02). The increase in TWD was 368% in the LTP group and 529% in the STP group (161% difference; p<0.02). In both groups there was a significant increase in PFWD and TWD at 4 and 20 weeks, but results obtained with STP are better considering both walking distances. No serious drug-related side effects were observed. Local, mild adverse reactions were seen in 6.3% of the treated subjects in the LTP and 3% in the STP. Average cost of LTP was 6,664 Euro; for STP the average costs was approximately 1,820 E. The cost to achieve an improvement in walking distance of 1 m was 45.8 E with the LTP and 8.5 E with the STP (18% of the LTP cost; p<0.02). For an average 100% increase in walking distance the LTP cost was 1,989 E vs. 421 E with STP (p<0.02). Between-group analysis favors STP considering walking distance and costs. Results indicate good efficacy and tolerability of PGE, treatment. With STP less time is spent in infusion and more in the exercise program. STP reduces costs, speeds rehabilitation, and may be easily used in a larger number of nonspecialized units.

Nomograms used to define the short-term treatment with PGE(1) in patients with intermittent claudication and critical ischemia. The ORACL.E (Occlusion Revascularization in the Atherosclerotic Critical Limb) Study Group. The European Study

Infusional, cyclic PGE1 treatment is effective in patients with intermittent claudication and critical limb ischemia (CLI). One of the problems related to chronic PGE1 treatment in vascular diseases due to atherosclerosis is to evaluate the variations of clinical conditions due to treatment in order to establish the number of cycles per year or per period (in severe vascular disease reevaluation of patients should be more frequent) needed to achieve clinical improvement. In a preliminary pilot study a group of 150 patients (mean age 67+/-12 years) with intermittent claudication (walking range from 0 to 500 m) and a group of 100 patients with CLI (45% with rest pain, and 55% gangrene; mean age 68 +/-11 years) the number of PGE1 cycles according to the short-term protocol (STP) needed to produce significant clinical improvement was preliminarily evaluated. Considering these preliminary observations, the investigators established a research plan useful to produce nomograms indicating the number of cycles of PGE1-STP per year needed to improve the clinical condition (both in intermittent claudication and CLI). A significant clinical improvement was arbitrarily defined as the increase of at least 35% in walking distance (on treadmill) and/or the disappearance of signs and symptoms of critical ischemia in 6 months of treatment in at least 75% of the treated patients. With consideration of the results obtained with the preliminary nomograms a larger validation of the nomograms is now advisable. A cost-effectiveness analysis is also useful to define the efficacy of treatment on the basis of its costs. The publication of this report in two angiological journals (Angeiologie and Angiology) will open the research on nomograms to all centers willing to collaborate to the study. The data are being collected in the ORACL.E database and will be analyzed within 12 months after the publication of this report.

[Drugs for veno-lymphatic insufficiency]

Treatment of venous and lymphatic insufficiency of the lower limbs is based on 3 components: elastic support, venotonic drugs and radical treatments (surgery or sclerotherapy) of insufficient veins. Venotonic drugs have specific indications limited to functional impairment: heavy feeling in the legs, pain and impatience in the evening. There are different categories of venolymphatic drugs. Flavonoids have various pharmacological actions, most notably an increase in venous tone, reduction of capillary permeability and increase of capillary resistance. Choice of a venotonic drug is funded on knowledge of pharmacodynamics and pharmacokinetics of the molecule, critical evaluation of clinical studies, physician's personal experience and drug cost. Venotonic drugs are useful when venous insufficiency leads to functional manifestations. They are especially the treatment of heavy leg syndromes during warm seasons when elastic support is uncomfortable.

Cost utility analysis of sildenafil compared with papaverine-phentolamine injections

OBJECTIVE

To compare the cost effectiveness of sildenafil and papaverine-phentolamine injections for treating erectile dysfunction.

DESIGN

Cost utility analysis comparing treatment with sildenafil (allowing a switch to injection therapy) and treatment with papaverine-phentolamine (no switch allowed). Costs and effects were estimated from the societal perspective. Using time trade-off, a sample of the general public (n=169) valued health states relating to erectile dysfunction. These values were used to estimated health related quality of life by converting the clinical outcomes of a trial into quality adjusted life years (QALYs).

PARTICIPANTS

169 residents of Rotterdam.

MAIN OUTCOME MEASURES

Cost per quality adjusted life year.

RESULTS

Participants thought that erectile dysfunction limits quality of life considerably: the mean utility gain attributable to sildenafil is 0.11. Overall, treatment with sildenafil gained more QALYs, but the total costs were higher. The incremental cost effectiveness ratio for the introduction of sildenafil was pound sterling 3639 in the first year and fell in following years. Doubling the frequency of use of sildenafil almost doubled the cost per additional QALY.

CONCLUSIONS

Treatment with sildenafil is cost effective. When considering funding sildenafil, healthcare systems should take into account that the frequency of use affects cost effectiveness.

[Comparative antianginal efficiency of prolonged nitrites in patients treated surgically for ischemic heart disease]

To compare clinical and cost effects of prolonged nitrates (sustac-forte), isosorbide dinitrate (nitrosorbide) and isosorbide-5-mononitrate (mono mac 40), a retrospective analysis was made of 112 cases of ischemic heart diseases (functional class II-III) treated surgically. During their rehabilitation in sanatorium 30-40 days after coronary artery bypass operation the patients received sustac forte (n = 37), nitrosorbide (n = 36), mono mac 40 (n = 39). By clinico-functional effect mono-mac appeared 1.5-2 times more effective than sustac forte or nitrosorbide. By cost-effect parameters, a course 30-day treatment was the cheapest when made with mono mac (3 times more cost effective than sustac-forte and 2 times more effective than nitrosorbide).

Cost-effectiveness analysis of nimodipine treatment after aneurysmal subarachnoid hemorrhage and surgery

OBJECTIVE

To assess the cost-effectiveness ratio of nimodipine administration after aneurysmal subarachnoid hemorrhage (SAH) and surgery.

METHODS

One hundred twenty-seven patients of both sexes who had a ruptured aneurysm (verified using angiography), who presented with Hunt and Hess Grades I to III on admission, who underwent an operation within the first week after SAH, and who had participated in a randomized prospective clinical trial of nimodipine medication were enrolled in the study. The efficiency (cost-effectiveness) of nimodipine treatment was evaluated by incremental cost-effectiveness analysis. The cost-effectiveness ratio was evaluated for two groups: patients treated with nimodipine and patients given placebo. The cost was estimated as direct hospitalization costs, and the patient outcome was measured as life years gained.

RESULTS

The incremental cost-effectiveness ratio for nimodipine treatment was $223 per life year gained on the basis of 1996 monetary values and contemporary management of SAH. Patients in the nimodipine group had an average of 3.46 years longer life expectancy (incremental effectiveness) than those in the placebo group. There was a significant difference in 3-month follow-up mortality and a slight difference in sickness pensions during the 10 years after SAH. Nimodipine treatment was associated with a significant decrease in mortality. There were no statistically significant differences between the treatment groups in the length of hospital stay. There were no statistically significant differences between the treatment groups in sickness pensions.

CONCLUSION

Nimodipine is cost-effective. Therefore, its use in the management of patients with SAH seems economically justified because it increases patient life years at very low incremental cost.

Withdrawal of peripheral vasodilators in primary care

AIMS

To investigate the use of peripheral vasodilators in selected practices in primary care and to observe the effect of withdrawing therapy in a sample of patients.

METHODS

Patients receiving repeat prescriptions for peripheral vasodilators, identified from two practices in Grampian, were interviewed prior to and following withdrawal of therapy.

RESULTS

Of the 35 patients, review of the continued need for therapy was documented in the medical notes of only one patient. Treatment was successfully withdrawn from 17 patients, generating considerable savings.

CONCLUSIONS

Review of peripheral vasodilators merits further attention in larger numbers of patients.

Cost effectiveness of carvedilol for heart failure

In this study, we examine the cost effectiveness of carvedilol for the treatment of chronic heart failure (CHF). We use a Markov model to project life expectancy and lifetime medical care costs for a hypothetical cohort of patients with CHF who were assumed alternatively to receive carvedilol plus conventional therapy (digoxin, diuretics, and angiotensin-converting enzyme inhibitors) or conventional therapy alone. Patients on carvedilol were assumed to experience a reduced risk of death and hospitalization for CHF, which is consistent with findings from the US Carvedilol Heart Failure Trials Program. The benefits of carvedilol were projected under 2 alternative scenarios. In the first ("limited benefits"), benefits were conservatively assumed to persist for 6 months, the average duration of follow-up in these clinical trials, and then end abruptly. In the other ("extended benefits"), they were arbitrarily assumed to persist for 6 months and then decline gradually over time, vanishing by the end of 3 years. We estimated our model using data from the US Carvedilol Heart Failure Trials Program and other sources. For patients receiving conventional therapy alone, estimated life expectancy was 6.67 years; corresponding figures for those also receiving carvedilol were 6.98 and 7.62 years under the limited and extended benefits scenarios, respectively. Expected lifetime costs of CHF-related care were estimated to be $28,756 for conventional therapy, and $36,420 and $38,867 for carvedilol (limited and extended benefits, respectively). Cost per life-year saved for carvedilol was $29,477 and $12,799 under limited and extended benefits assumptions, respectively. The cost effectiveness of carvedilol for CHF compares favorably to that of other generally accepted medical interventions, even under conservative assumptions regarding the duration of therapeutic benefit.

[Costs and benefits of heart failure treatment]

Congestive heart failure constitutes an important public health problem, because of its prevalence and mortality, and also its morbidity and significant resource utilization. It is the main cause of hospitalization for patients aged 65 or over, and it absorbs 2% of the health care budget in industrialized countries. With the aging of the population and the advancing age of the baby boom generation, the situation will worsen: the prevalence of congestive heart failure in Europe may increase by 70% by the year 2010. To favourably alter these economic consequences, treatment must not only prolong life but also slow down or even prevent disease progression towards more severe stages and decrease resource utilization, mainly in reducing the need for hospital admissions. To date, the most convincing results of economic analyses concern vasodilators: the hydralazine-isosorbide dinitrate combination and angiotensin converting enzyme inhibitors (ACE). Even if all these studies do not come to the same conclusions in terms of numbers, they agree in showing that costs per year of life saved by vasodilators, and particularly by ACE, are very favourable (< $10,000 per year of life saved) and much lower than those of most other well accepted medical strategies.

[Changes in prescription patterns for peripheral and cerebral vasoactive drugs before and after establishing prescription standards in France]

OBJECTIVES

Assess changes in the number of prescriptions for peripheral and cerebral vasoactive drugs for the treatment of lower limb arteritis and cerebrovascular disease since the promulgation in 1995 of prescription standards for the treatment of lower limb arteritis. Assess compliance to prescription standards with a detailed analysis of patient features, prescriptions written for lower limb arteritis, cerebrovascular disease and concomitant diseases and evaluate changes in treatment costs for lower limb arteritis and cerebrovascular disease as well as cost of the full prescription, including treatments for associated diseases.

METHODS

This study was based on data recorded during the Permanent Study of Medical Prescriptions conducted from March 1994 to February 1995 and from March 1995 to February 1996 by the IMS. Prescription costs were established from the National Description Files of the IMS. Treatment costs were expressed as public price (FF) tax included. Prescriptions meeting the following criteria were selected for each period: prescriptions written by general practitioners for drugs with peripheral and cerebral vasoactivity (excepting calcium antagonists with a cerebral target) belonging to the Anatomic Therapeutic Classes C4A1 of the European Pharmaceutical Marketing Research Association, Bromly 1996; prescriptions for diagnoses 447.6 (arteritis) and 437.9 (cerebrovascular disease) according to the 9th WHO classification. A random sample of 500 prescriptions was selected to calculate costs.

RESULTS

Since the advent of the prescription standards in 1995, prescriptions have dropped off by 6.3% for lower limb arteritis and by 14.8% for cerebrovascular disease. There was a 3.7 point decline in the percentage of multiple prescriptions of vasoactive drugs for lower limb arteritis (21.7% prior to March 1995 versus 18% after promulgation of the prescription standards, p > 0.1) and a 1.8 increase in the percentage of multiple prescriptions for cerebrovascular disease (14% prior to March 1995 and 15.8% after promulgation of the prescription standards, p > 0.1). For the treatment of lower limb arteritis, prescription costs fell by a mean 9% per prescription and for the treatment of cerebrovascular disease they rose by a mean 7% per prescription. The price rise, due to multiple prescriptions of vasoactive drugs was 190 FF per prescription for lower limb arteritis and 104 FF per prescription for cerebrovascular disease.

CONCLUSION

Despite the retrospective nature of this study where confounding factors could not be controlled, our findings are in agreement with those reported earlier suggesting that cost containment policy implemented by the prescription standards has had little efficacy. In patients with arterial disease of the lower limbs, the percentage of prescriptions not complying with the recommended standards decreased by one-third to one-half over a 2-year period since the prescription standards were first announced in 1994.

Evaluation of amlodipine dosing for conversion of nifedipine extended-release to amlodipine in the treatment of hypertension

OBJECTIVE

To evaluate the appropriate dosing of amlodipine when converting patients from nifedipine extended-release (nifedipine ER) to amlodipine in the treatment of hypertension.

METHODS

Patients of the Outpatient Clinic of Cheyenne Veterans Affairs Medical Center, Wyoming, receiving nifedipine ER for the management of hypertension (systolic BP or SBP > 140 mm Hg and diastolic BP or DBP > 90 mm Hg), participated in this study. Nifedipine ER was changed to amlodipine on entry into this study. An inclusion criterion was the BP had to be under control (SBP < 140 mm Hg and DBP < 90 mm Hg) before the switch. The BP in each study patient was monitored once weekly (once every 2 wk in some patients) for a total of six clinic visits or until BP was under control. Dosing titration of amlodipine was required in 16 of 27 patients after the switch. To assess the adequacy of the conversion, the statistical significance of the difference of the mean BP values before and at the end of the monitoring period was estimated by using the t-test for paired data.

RESULTS

Twenty-seven male patients completed this study. BP in all study patients was adequately controlled after nifedipine ER was switched to amlodipine. The SBP and DBP values before and after the switch were similar (SBP: 124 +/- 12 vs. 126 +/- 9 mm Hg, CI of the mean difference -6.10 to 1.80; DBP: 76 +/- 8 vs. 76 +/- 7 mm Hg, CI of the mean difference -2.45 to 3.63). Initial amlodipine dose of 5 or 10 mg once daily was used in our study. No serious adverse effects were observed in any of the study patients after the drug switch.

CONCLUSIONS

This study indicates the amlodipine dosage of 5 or 10 mg once daily can be used when nifedipine ER is converted to amlodipine in the treatment of hypertension. Dosage titration of amlodipine may be required to obtain adequate control of BP.

Treatment of severe intermittent claudication with PGE1--a short-term vs a long-term infusion plan--a 20 week, European randomized trial--analysis of efficacy and costs

The efficacy, safety, and cost of prostaglandin E1 (PGE1) in the treatment of severe intermittent claudication was studied by comparing a long-term treatment protocol (LTP) with a short-term treatment protocol (STP) in a randomized 20-week study. The study included 109 patients (96 completed the study) with an average total walking distance of 65.5 +/- 8 m (range 20-109). Phase 1 was a 2-week run-in phase (no treatment) for both protocols. In LTP, phase 2 was the main treatment phase. In the LTP, treatment was performed with 2-hour infusions (60 microg PGE1, 5 days each week for 4 weeks). In phase 3 (4-week interval period) PGE1 was administered twice a week (same dosage). In phase 4 (monitoring lasting 3 months, from week 9 to 20) no drugs were used. In STP, phase 2 treatment was performed in 2 days by a 2-hour infusion (1st day: morning 20 microg, afternoon 40 microg; 2nd day morning and afternoon 60 microg). The reduced dosage was used only at the first cycle (week 0) to evaluate reduced tolerability or side effects. Full dosage (60 microg b.i.d.) was used for all other cycles. The same cycle was repeated at the beginning of weeks 4, 8, and 12. The observation period was between weeks 12 and 20. A treadmill test was performed at inclusion, at the beginning of each phase, and at the end of the 20th week. A similar progressive physical training plan (based on walking) and a reduction in risk factors levels plan was used in both groups. Intention-to-treat analysis indicated an increase in walking distance, which improved at 4 weeks (101.5% in STP vs 78.3% in LTP), at 8 weeks (260.9% STP vs 107.3% LTP), and at 20 weeks (351% STP vs 242% LTP). Comparable increases in pain-free walking distance were observed in the two groups. No serious drug-related side effects were observed. Local, mild adverse reactions were seen in 7% of the treated subjects in the LTP and 5% in the STP. Average cost of LTP was approximately 6,588 ECU; for STP the average cost was approximately 1,881 ECU. The cost to achieve an improvement in walking distance of 1 m was 35.6 ECU with the LTP and 9.45 ECU with the STP (26% of the LTP cost; p<0.02). For an average 100% increase in walking distance the LTP cost was 1,937 ECU vs 550 ECU with STP (p<0.02). The cost of PGE1 (including infusion and operative costs) was 25% of the total cost for LTP (24.9% for STP). In summary, between-group-analysis favors STP, in terms of walking distance and costs. Results indicate good efficacy and tolerability of PGE1 treatment. With STP less time is spent in infusion and more can be spent in the exercise program. STP reduces costs, speeds up rehabilitation, and may be used in a larger number of nonspecialized units available to follow the protocol.

The German experience in reference pricing

Price regulation schemes function both as a means for public authorities to contain costs, and as an economic tool to support the national pharmaceutical industry. This twofold contradictory aim of public intervention in pharmaceutical demand and supply makes such pricing schemes difficult to apply. This article concerns the reference price scheme which concerns setting a price cap for each active ingredient, or group of active ingredients considered equivalent according to some feature (e.g. therapeutic effects and chemical structure). In 1989, the reference price scheme for reimbursable drugs was introduced in Germany to reduce pharmaceutical expenditure, which had been steadily increasing in the past. The study investigates the economic effects of introducing reference prices in Germany in order to assess whether this system has been effective in containing public pharmaceutical expenditure. We conclude that the reference price scheme is an effective tool for price control, but cost containment requires further measures.

A randomised crossover comparison of reserpine and sustained-release nifedipine in hypertension

OBJECTIVE

To compare the effectiveness of the combination of hydrochlorothiazide (HCT) plus sustained-release nifedipine with the combination of HCT plus reserpine in lowering high blood pressure (BP) unresponsive to HCT monotherapy.

DESIGN

An open, randomised crossover drug trial.

SETTING

Outpatients' clinic in Parirenyatwa Hospital, Harare, a tertiary referral centre.

SUBJECTS

32 Black patients of both sexes with newly diagnosed or previously treated hypertension aged between 21 and 65 years who had a BP > 140/95 after receiving HCT 25 mg daily for four weeks were studied.

INTERVENTION

Patients were kept on HCT 25 mg daily and were randomised to receive either reserpine 0.25 mg daily or nifedipine (Adalat Retard) 20 mg bd for four weeks. This was followed by a two week washout period during which patients received HCT 25 mg daily only. After the washout period patients were crossed over to the alternative treatment for four weeks. Patients were kept on HCT 25 mg daily throughout the trial.

MAIN OUTCOME MEASURES

The main outcome measure was the fall in BP which was taken as the difference between the BP at baseline and the BP at the end of each treatment period. Both systolic blood pressure (SBP) and diastolic blood pressure (DBP) measurements were taken.

RESULTS

Both second line drugs were effective in lowering SBP and DBP and there was no significant difference between them. Nifedipine reduced SBP by 18.9 mmHg (95% CI 12.1 to 25.7) and DBP by 9.6 mmHg (95% CI 7.2 to 12.0). Reserpine reduced SBP by 15.9 mmHg (95% CI 8.4 to 23.4) and DBP by 11.1 mmHg (95% CI 7.5 to 14.6). However, only two patients attained the target DBP of < or = 90 mmHg after each active treatment period.

CONCLUSION AND RECOMMENDATIONS

Since both agents were equally effective in reducing both SBP and DBP and reserpine is much cheaper than nifedipine, it is recommended that for a developing country like Zimbabwe, the combination of HCT and reserpine at the above doses should be used as the first step to treat mild to moderate hypertension without evidence of end organ damage. However, further trials should compare BP lowering effects as well as end organ protection offered by the trial drugs.

A controlled letter intervention to change prescribing behavior: results of a dual-targeted approach

OBJECTIVE

To determine the effectiveness of a drug utilization review (DUR) letter intervention sent only to physicians, sent only to pharmacists, or sent to both physicians and pharmacists in changing physician prescribing behavior for dipyridamole.

DATA SOURCES/STUDY SETTING

A Wisconsin Medicaid prescription drug database for data from March 1991 through May 1992 related to both long-term care and ambulatory patient settings.

STUDY DESIGN

The effects of a DUR letter intervention were tested using a field study, pre-post, nonequivalent control group, quasi-experimental design. The effects of the letter intervention in terms of dipyridamole expenditures (dollars reimbursed to pharmacies by Medicaid), expenditures for related drugs (aspirin, ticlopidine, sulfinpyrazone) and numbers of patients for whom dipyridamole was discontinued were examined across three experimental groups and a control group.

DATA COLLECTION/EXTRACTION METHODS

Dipyridamole expenditures for each study patient during a six-month preintervention and six-month postintervention period were collected from Medicaid prescription drug claims. Patients who had zero dipyridamole expenditures throughout the six-month postintervention period were classified as having had dipyridamole discontinued.

PRINCIPAL FINDINGS

Letters sent to both physicians and pharmacists resulted in a greater percentage of patients discontinuing dipyridamole relative to controls and statistically significant differences in postintervention dipyridamole expenditures relative to controls in both the long-term care and ambulatory patient populations.

CONCLUSIONS

Interventions that focus on another person in the drug use process in addition to the physician may have greater effects on a change in the prescribing of a targeted drug than letters to physicians alone.

Cost-minimization analysis of intravenous adenosine and dipyridamole in thallous chloride TI 201 SPECT myocardial perfusion imaging

OBJECTIVE

To conduct a cost-minimization analysis of intravenous adenosine and intravenous dipyridamole in thallous chloride TI 201 single-photon emission computed tomography (SPECT) myocardial perfusion imaging.

DESIGN

A retrospective, open-label, cost-minimization analysis.

SETTING

University hospital, outpatient nuclear medicine department.

PATIENTS

Eighty-three patients undergoing dipyridamole TI 201 SPECT and 166 patients undergoing adenosine TI 201 SPECT.

MAIN OUTCOME MEASURES

A cost-minimization analysis was conducted using a direct cost accounting approach estimating institutional costs. For the purpose of this study, sensitivity and specificity between adenosine SPECT and dipyridamole SPECT were assumed to be identical. Key costs evaluated included acquisition, administration, monitoring, treatment of adverse effects, follow-up care, and repeat tests.

RESULTS

Adenosine increased heart rate and lowered blood pressure to a significantly greater extent than dipyridamole. The frequency of adverse reactions was not significantly different (p = 0.103) between adenosine (1.64 +/- 1.32 per patient) and dipyridamole (1.36 +/- 1.23 per patient). The frequency of prolonged and late-onset adverse effects was significantly greater for dipyridamole than for adenosine (p < 0.001). The frequency of adverse events requiring medical intervention was statistically greater for dipyridamole (24%) compared with adenosine (5%) (p < 0.00001). Total cost was significantly less for adenosine ($378.50 +/- $128.20 per patient) compared with dipyridamole ($485.60 +/- $230.40). Although adenosine had a significantly greater acquisition cost than dipyridamole (p < 0.0001), administration, monitoring, and adverse reaction costs were significantly less for adenosine than for dipyridamole.

CONCLUSIONS

The cost of using dipyridamole is significantly greater than the cost of using adenosine despite adenosine's high acquisition cost. Adenosine is less expensive to use because of lower administration costs, monitoring costs, and adverse effect costs. Adenosine should be the agent of choice for pharmacologic vasodilation in the setting of myocardial perfusion imaging.

Outcomes and costs of positron emission tomography: comparison of intravenous adenosine and intravenous dipyridamole

The objective of this study was to compare the cost of intravenous adenosine and intravenous dipyridamole in positron emission tomography (PET) in patients with coronary artery disease. A retrospective, open-label, case-control, cost-effectiveness analysis was performed in the out-patient nuclear medicine department of a university hospital. Thirty-six patients underwent dipyridamole PET, and 72 matched patients underwent adenosine PET. A cost-effectiveness analysis was conducted using a direct cost accounting approach to estimate institutional costs. Key costs evaluated included acquisition cost, administration cost, monitoring cost, cost of management of side effects, and cost of follow-up care. The total cost of adenosine PET and dipyridamole PET was divided by their respective predictive accuracies to provide a total cost adjusted for efficacy. Adenosine increased heart rate and lowered systolic blood pressure to a significantly greater extent than dipyridamole. The number of patients experiencing adverse drug reactions was significantly greater for adenosine (82%) than for dipyridamole (67%), but the frequency of prolonged (> 5 minutes) and late-onset side effects was significantly greater for dipyridamole than for adenosine. The frequency of side effects requiring medical intervention was also significantly greater for dipyridamole (53%) than for adenosine (6%). Although adenosine had a significantly greater acquisition cost than dipyridamole, costs of monitoring, management of side effects, and follow-up care were significantly less for adenosine than for dipyridamole. As a result, the total cost of using dipyridamole is significantly greater ($928.00 per patient) than the total cost of using adenosine ($672.00 per patient). Based on these results, adenosine may be the drug of choice for pharmacologic vasodilation for PET.

Is medical treatment for angina the most cost-effective option?

A meta-analysis of the benefits of coronary artery bypass graft (CABG) surgery has been used as the basis of a model for comparing the costs and benefits of surgical and medical treatment of angina pectoris. In order to allow for the results of recent research, the economic model included the addition of aspirin and aspirin plus an HMG-CoA reductase inhibitor (statin) to medical management. The analysis indicates that in unselected patients the cost-effectiveness of CABG vs initial standard medical therapy over 5 years is towards the upper limit of what can be considered a cost-effective treatment both in terms of its effect on mortality (life-years gained) and morbidity (quality adjusted life-years). Addition of a statin to medical therapy reduced mortality and made coronary artery bypass graft surgery an expensive option in terms of improvement of quality of life. In patients with three-vessel disease or left ventricular dysfunction surgery appears fairly cost-effective in comparison with standard medical therapy but becomes relatively expensive when the benefits of aspirin or lipid-lowering therapy are added to medical treatment.

Cost analysis of once-daily ISMN versus twice-daily ISMN or transdermal patch for nitrate prophylaxis

OBJECTIVE

To compare the costs and outcomes of treating exercise-induced angina with once- or twice-daily isosorbide mononitrate (ISMN) or transdermal patch.

METHOD

A decision-analytic model was designed based on published literature showing compliance and increasing symptoms and estimates from physicians on treatment patterns and worsening symptoms.

RESULTS

Data show that patients are more compliant with once-daily ISMN (Imdur, Astra Hässle, Mölndal, Sweden) and patch regimens than with twice-daily dose. Based upon the assumption that more compliant patients are better controlled, the model found that fewer medical care resources were consumed by patients treated with the once-daily and the patch regimens. The unit cost of the twice-daily ISMN regimen is 40% of the unit cost of the once-daily. Annual costs of treating an exercise-induced angina patient are 248 pounds for Imdur compared to 250 pounds for the twice-daily ISMN and 299 pounds for the transdermal patch.

CONCLUSION

Unit prices alone are not good indicators for estimating medical management costs.

Cardiac assessment prior to vascular surgery: is dipyridamole-sestamibi necessary?

Dipyridamole-sestamibi (PMIBI) is recommended prior to vascular surgery in patients with > or = 1 Eagle criteria (Q waves, history of ventricular ectopy, diabetes, advanced age, and/or angina). To review our cardiac morbidity and mortality and the need for preoperative PMIBI, we reviewed 109 consecutive patients with a mean age of 59 years who underwent 145 elective major vascular procedures over a 1-year period. Seventy patients (with a mean of 0.8 Eagle criteria) underwent 92 vascular procedures without preoperative PMIBI and without coronary revascularization. Thirty-one patients (with a mean of 1.1 Eagle criteria) underwent 39 procedures without coronary revascularization following PMIBI, which showed reversible ischemia in seven and a fixed defect in 10; findings were normal in 14. Preoperative coronary bypass or angioplasty was limited to eight patients (14 procedures, mean of 1.6 Eagle criteria) who had unstable angina with (2 patients) or without (6 patients) acute myocardial infarction. There were four perioperative myocardial infarctions (2.8%), seven cardiac events overall (4.8%), and one cardiac death (0.7%). Three (43%) of the seven cardiac events occurred in patients with a normal scan or fixed defect on PMIBI imaging. In the absence of unstable angina, PMIBI had a sensitivity of only 25% and a specificity of 80% for cardiac events. We conclude that among patients without severe cardiac symptoms (1) PMIBI has a very limited ability to identify patients at risk for cardiac complications, and (2) preoperative PMIBI is neither necessary nor cost-effective.

A cost analysis of alprostadil in liver transplantation

Alprostadil (prostaglandin E1) administration to liver transplant recipients has been shown to result in a significant reduction in the duration of hospital admission for transplantation, and in the need for re-operations (other than re-transplants) and renal support. To study the economic impact of this finding, we examined data from a controlled trial for all single-transplant surviving patients (42 alprostadil, 49 controls) for whom complete billing records were available for transplant days -2 to +150. All costs were measured in 1992 US dollars. Patients given alprostadil had lower total charges [mean +/- standard deviation (SD) $US175 297 +/- $US70 652] than patients given placebo (mean +/- SD $US225 672 +/- $US187 208) [p = 0.043]. The data suggest that the use of alprostadil may have a significant favourable impact on the cost of liver transplantation.

The Economics of Cardiac Failure

Quality assurance and inclusion of prospective evaluation of costs of treatment in phase 3 and 4 pharmaceutical trials are becoming increasingly important. Not only high technology applications have to be investigated, but also relatively cheap but very common strategies for diagnostic work up and therapy. This may yield major savings. We are at the beginning of an era in which waste of resources may be reduced by scientific analysis with improvement in patient care and teaching achieved as a result.

Change in prescribing patterns of general practitioners in Italy before and after the Reform Drug Act. A case study of changes in the city of Turin

As of 1 January 1994, the introduction of a new classification of the drugs to be reimbursed by the National Health Service was approved by the Italian parliament in order to limit expenditure on pharmaceutical agents. This has set off a 'cultural revolution', unprecedented in Italy. The criteria that inspired the expert group charged with attributing drugs to different classes (Class A: essential, free of charge drugs; Class B: drugs to be paid for 50% by the patient; Class C: drugs to be paid entirely by the patient) were principally scientific rather than merely economic or administrative. Expectedly, the creation of Class C (drugs not reimbursed by the National Health Service on account of their insufficiently proven clinical effectiveness, or their unfavourable cost/benefit ratio with respect to therapeutically equivalent agents) has provoked remarkable changes in general practitioners' prescription options, particularly given the fact that many of these drugs were among the most prescribed in Italy. A database including the prescriptions of about 940 general practitioners, dispensed through the 280 community pharmacies of the city of Turin, has been analysed for a comparative sample of time periods in 1993 and 1994, in order to quantify the changes that occurred and to qualify them with respect to more relevant therapeutic groups and sentinel drugs.