Wessels F, Anderson A N, Kropman K
S Afr Med J. 1999 Jul;89(7 Pt 2):791-4.
The cost-effectiveness of systemic isotretinoin therapy in the treatment of moderate to severe acne was assessed in a comparative cost-minimisation analysis. Systemic isotretinoin at the recommended daily dose of 1 mg/kg (cumulative dose of 120 mg/kg) was compared with: (i) oral antibiotics taken as chronic medication; (ii) a combination of chronic oral antibiotics and anti-androgen therapy; and (iii) isotretinoin prescribed only after two failed courses of oral antibiotics, as per South African guidelines. The perspective taken was that of the funder of health care, and the resources used were funder charges as a proxy for costs.
Statistical and epidemiological data as well as relevant costs from the previously reported meta-analysis and profiling study for acne therapy were used as the clinical basis for the construction of a cost-minimisation model. Additional costs were sourced from published pharmaceutical retail prices and professional rates. The South African treatment guidelines were used to define the frequencies associated with physician visits and pathology testing. Standard statistical methods were applied, as appropriate. From the above, a modified Markov process was used to model the costs associated with the four comparator treatment regimens over a period of 120 months. Suitable clinical and economic endpoints were defined so that comparison could be made between regimens.
Assuming a relapse rate of 21.45%, it was found that isotretinoin therapy compares favourably with the other regimens. After 50 and 35 months, systemic isotretinoin cumulative costs were less than those incurred in oral antibiotic and oral antibiotic/anti-androgen therapy, respectively. For the stepped therapy of oral antibiotics followed by systemic isotretinoin, these break-even periods were 56 and 39 months, respectively. The cost per successfully treated patient receiving isotretinoin was R8941. This compares well with the cost for those patients receiving chronic oral antibiotics, which after 5 years amounted to R10 428 per patient. Sensitivity analyses proved these findings to be robust to variations in the isotretinoin relapse rate, and the cost of oral antibiotic therapy and the concomitant use of topical therapies.
From the cost-minimisation model it is clear that where systemic isotretinoin is clinically indicated, the sooner such therapy is initiated the more cost-effective the outcome will be. If isotretinoin is prescribed on diagnosis of moderate to severe acne, then the cost of treatment is significantly reduced in the long term when compared with standard chronic oral antibiotic therapy.
在一项比较成本最小化分析中评估系统性异维A酸疗法治疗中度至重度痤疮的成本效益。将推荐日剂量为1mg/kg（累积剂量为120mg/kg）的系统性异维A酸与以下治疗方法进行比较：（i）作为长期用药的口服抗生素；（ii）长期口服抗生素与抗雄激素疗法的联合使用；（iii）按照南非指南，仅在两个口服抗生素疗程失败后才开具异维A酸。所采用的视角是医疗保健资助者的视角，所使用的资源是以资助者收费作为成本的替代指标。
将先前报道的痤疮治疗荟萃分析和概况研究中的统计和流行病学数据以及相关成本用作构建成本最小化模型的临床依据。额外成本来自已公布的药品零售价格和专业费率。南非治疗指南用于确定与医生就诊和病理检查相关的频率。酌情应用标准统计方法。据此，采用改良的马尔可夫过程对120个月内与四种对照治疗方案相关的成本进行建模。定义了合适的临床和经济终点，以便能够在各治疗方案之间进行比较。
假设复发率为21.45%，发现异维A酸疗法与其他治疗方案相比具有优势。在50个月和35个月后，系统性异维A酸的累积成本分别低于口服抗生素和口服抗生素/抗雄激素疗法的累积成本。对于先口服抗生素后使用系统性异维A酸的阶梯疗法，这些收支平衡期分别为56个月和39个月。接受异维A酸治疗的每位成功治愈患者的成本为8941兰特。这与接受长期口服抗生素治疗的患者成本相比具有优势，5年后每位患者的成本为10428兰特。敏感性分析证明，这些结果对于异维A酸复发率、口服抗生素治疗成本以及局部治疗的联合使用的变化具有稳健性。
从成本最小化模型可以明显看出，在临床指征适合使用系统性异维A酸的情况下，越早开始这种治疗，结果就越具成本效益。如果在诊断为中度至重度痤疮时就开具异维A酸，那么与标准的长期口服抗生素治疗相比，从长期来看治疗成本会显著降低。
