Decollogny Anne, Piaget-Rossel Romain, Taffé Patrick, Eggli Yves
Institute of Social and Preventive Medicine, Centre Hospitalier Universitaire Vaudois and Faculty of Biology and Medicine, Route de la Corniche 10, 1010, Lausanne, Switzerland.
BMC Health Serv Res. 2018 Jan 9;18(1):9. doi: 10.1186/s12913-017-2775-1.
Drug markets are very complex and, while many new drugs are registered each year, little is known about what drives the prescription of these new drugs. This study attempts to lift the veil from this important subject by analyzing simultaneously the impact of several variables on the prescription of novelty.
Data provided by four Swiss sickness funds were analyzed. These data included information about more than 470,000 insured, notably their drug intake. Outcome variable that captured novelty was the age of the drug prescribed. The overall variance in novelty was partitioned across five levels (substitutable drug market, patient, physician, region, and prescription) and the influence of several variables measured at each of these levels was assessed using a non-hierarchical multilevel model estimated by Bayesian Markov Chain Monte Carlo methods.
More than 92% of the variation in novelty was explained at the substitutable drug market-level and at the prescription-level. Newer drugs were prescribed in markets that were costlier, less concentrated, included more insured, provided more drugs and included more active substances. Over-the-counter drugs were on average 12.5 years older while generic drugs were more than 15 years older than non-generics. Regional disparities in terms of age of prescribed drugs could reach 2.8 years.
Regulation of the demand has low impact, with little variation explained at the patient-level and physician-level. In contrary, the market structure (e.g. end of patent with generic apparition, concurrence among producers) had a strong contribution to the variation of drugs ages.
药品市场非常复杂，虽然每年有许多新药注册，但对于推动这些新药处方的因素却知之甚少。本研究试图通过同时分析多个变量对新药处方的影响，揭开这个重要课题的面纱。
分析了四家瑞士疾病基金提供的数据。这些数据包括47万多名参保人的信息，尤其是他们的药物摄入情况。反映新药的结果变量是所开药物的使用年限。新药使用年限的总体差异在五个层面（可替代药品市场、患者、医生、地区和处方）进行划分，并使用贝叶斯马尔可夫链蒙特卡罗方法估计的非分层多水平模型评估在每个层面测量的多个变量的影响。
超过92%的新药使用年限差异在可替代药品市场层面和处方层面得到解释。在成本更高、集中度更低、参保人更多、提供的药品更多且活性物质更多的市场中，会开出更新的药物。非处方药的平均使用年限比处方药大12.5年，而仿制药的使用年限比非仿制药大15年以上。所开药物使用年限的地区差异可能达到2.8年。
需求监管的影响较小，在患者层面和医生层面得到解释的差异很小。相反，市场结构（例如专利到期与仿制药出现、生产商之间的竞争）对药物使用年限的差异有很大影响。
