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Cost utility of maintenance treatment of recurrent depression with sertraline versus episodic treatment with dothiepin |
Hatziandreu E J, Brown R E, Revicki D A, Turner R, Martindale J, Levine S, Siegel J E |
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Record Status This is a critical abstract of an economic evaluation that meets the criteria for inclusion on NHS EED. Each abstract contains a brief summary of the methods, the results and conclusions followed by a detailed critical assessment on the reliability of the study and the conclusions drawn. Health technology Selective serotonin reuptake inhibitors versus tricyclic antidepressants.
Study population Model of 2 hypothetical cohorts of 35 year old women suffering from depression and at high risk of future depressive episodes (2 previous episodes of depression within past 4 years) over their lifetime.
Setting Primary care. The economic study was carried out in UK.
Dates to which data relate No dates are applicable to the effectiveness data. Direct drug costs are for 1992, other direct costs for 1989, prices are for 1991.
Source of effectiveness data Estimates of effectiveness were based on opinion.
Modelling A Markov model was used to estimate costs and benefits.
Methods used to derive estimates of effectiveness Estimates for effectiveness were derived from probabilities supplied by two separate physician panels (GPs and psychiatrists) who responded, on the basis of their experience and their knowledge of the literature, to a specifically designed questionnaire.
Estimates of effectiveness and key assumptions Effectiveness data was based on cumulative recurrence probabilities for major depressive episodes, by number and timing of recurrences. The derived probabilities indicate that patients receiving maintenance treatment are overall less likely to develop a recurrence than those receiving episodic treatment. Probabilities of additional recurrences increase as the time between recurrences decreases.
Measure of benefits used in the economic analysis Quality-adjusted-life-years were derived using a Markov model. Standardised health state descriptions and standard gamble scaling methods were used to generate utilities for 4 depression-related hypothetical health states. Health state utilities were based on the values assigned by the 2 panels via interview.
Direct costs Costs and quantities were reported separately. Costs were discounted at 5%. They were derived using a Markov model. The cost boundary was to the health service. Drug costs were from the Monthly Index of Medical Specialties and DoH and Welsh Office Drug Tariffs, all for 1992. Medical costs (professional services, facilities and tests) were from a published review of UK physician payments in 1991. Quantities of medical resource utilisation (including outpatient visits, tests, duration of therapy, and hospitalisation) were estimated from questionnaire responses from the clinical panel members and were summarised in terms of average resources used and were valued on CIPFA (1989) cost data.1991 prices were used.
Currency UK pounds sterling. A conversion was made to 1991 US $.
Sensitivity analysis Sensitivity analysis was undertaken. The authors varied utilities, compliance rates, treatment costs, recurrence and discount rates and the number of years of maintenance treatment. The method used was not specified.
Estimated benefits used in the economic analysis Sertraline yielded 14.94 QALYs; Dothiepin yielded 14.13 QALYs (both were discounted using a 5% discount rate). Duration of benefits was lifetime.
Cost results Lifetime costs were 3,407 for Sertraline and 1,648 for Dothiepin (both discounted at 5%)
Synthesis of costs and benefits The incremental cost per Qaly gained of sertraline versus dothiepin was 2,172 ($US 3632). The probability and timing of recurrence and compliance rates were sensitive parameters. The incremental cost per Qaly gained was 3839, if the recurrence rate is increased by 50% with SSRI therapy, and was 4962 under the assumptions of equal recurrence rates. If the compliance rate for both TCA and SSRI were 100%, the ratio would increase to 5260.
Authors' conclusions The results provide evidence that maintenance therapy with sertraline is a cost-effective strategy for patients with recurrent major depression who are at high risk of experiencing additional recurrent episodes. This also adheres to WHO clinical recommendations and is in line with previous results and involves a lower range than cost-utility ratios for other common interventions. The results are probably generalisable as differences in treatment costs and utilities are expected to influence the magnitude rather than the direction of the cost-utility ratio.
CRD Commentary This is a reasonable hypothetical study given that a prospective trial would have to be for 30 years to get lifetime results. But, the validity is compromised as 2 panels of 5 people may not be enough to generate utilities, particularly if results are to be generalisable and because the panel derived estimates are the most sensitive. Ideally, a larger panel or panels should have included patients with experience of depression.
Implications of the study Long term maintenance treatment with sertraline appears to be a clinically and economically justified choice for patients at high risk of recurrent depression.
Bibliographic details Hatziandreu E J, Brown R E, Revicki D A, Turner R, Martindale J, Levine S, Siegel J E. Cost utility of maintenance treatment of recurrent depression with sertraline versus episodic treatment with dothiepin. PharmacoEconomics 1994; 5(3): 249-264 Other publications of related interest Freemantle. N et al, Prescribing selective serotonin reuptake inhibitors as strategy for prevention of suicide. BMJ 1994;309(6949):249-253 (See also CRD Abstracts of reviews database).
Indexing Status Subject indexing assigned by NLM MeSH 1-Naphthylamine /analogs & Adult; Costs and Cost Analysis; Depression /drug therapy; Dothiepin /economics /therapeutic use; Female; Humans; Male; Models, Econometric; Quality of Life; Recurrence; Value of Life; derivatives AccessionNumber 21995007011 Date bibliographic record published 19/06/1995 Date abstract record published 19/06/1995 |
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