Roughead Elizabeth E, Zhang Fang, Ross-Degnan Dennis, Soumerai Stephen
Sansom Institute, School of Pharmacy and Medical Sciences, University of South Australia, Adelaide, Australia.
Med Care. 2006 Apr;44(4):378-82. doi: 10.1097/01.mlr.0000204056.31664.36.
State Medicaid programs introduce many types of prescribing restrictions to manage pharmaceutical use and expenditure. Little is known about the differential effect of implementing prior authorization (PA) policies at market entry versus waiting until several years later when prescribing behavior may already be established.
We sought to examine the impact on overall use of Cox II inhibitors of PA policies implemented at market entry versus at least 2 years after market entry.
We quantified Cox II inhibitor and nonselective nonsteroidal anti-inflammatory drug (NSAID) utilization for state Medicaid programs from January 1996 to September 2003. We used generalized estimating equations, Tukey's studentized range test and segmented linear regression on state Medicaid programs to determine the significance of changes in medication use.
The primary end point was the number of defined daily doses (DDD) per 1000 population per day.
Six states implementing prescribing restrictions for Cox II inhibitors at market entry had the lowest rates of uptake, averaging 10.9 DDD/1000/d. Twelve states adopting restrictions more than 2 years after market entry experienced declines in use from 23.0 DDD/1000/d before to 13.9 DDD/1000/d after the restrictions (P < 0.01). The 17 states that had never restricted access had the highest utilization, averaging 29.0 DDD/1000/d.
Implementing prescribing restrictions at market entry of Cox II inhibitors was effective in restricting uptake. Despite the difficulty in changing well-established prescribing patterns, utilization in states implementing policies 2 years after market entry approached that of the early adopting states within 1 year. Clinical outcomes of such policies remain unknown.
州医疗补助计划引入了多种处方限制措施，以管理药品使用和支出。对于在药品进入市场时实施预先授权（PA）政策与等到几年后处方行为可能已经确立时再实施的差异影响，我们知之甚少。
我们试图研究在药品进入市场时与进入市场至少2年后实施PA政策对Cox II抑制剂总体使用情况的影响。
我们对1996年1月至2003年9月期间州医疗补助计划中Cox II抑制剂和非选择性非甾体抗炎药（NSAID）的使用情况进行了量化。我们使用广义估计方程、Tukey的学生化极差检验和对州医疗补助计划的分段线性回归来确定药物使用变化的显著性。
主要终点是每1000人口每天的限定日剂量（DDD）数。
在药品进入市场时对Cox II抑制剂实施处方限制的6个州的采用率最低，平均为10.9 DDD/1000/天。在药品进入市场2年多后采取限制措施的12个州，使用量从限制前的23.0 DDD/1000/天下降到限制后的13.9 DDD/1000/天（P < 0.01）。从未限制使用的17个州的使用率最高，平均为29.0 DDD/1000/天。
在Cox II抑制剂进入市场时实施处方限制有效地限制了采用率。尽管改变既定的处方模式存在困难，但在药品进入市场2年后实施政策的州，其使用率在1年内接近早期采用该政策的州。此类政策的临床结果尚不清楚。
