Increasing Time Costs and Copayments for Prescription Drugs: An Analysis of Policy Changes in a Complex Environment

Abstract

Objective To estimate the effect of two separate policy changes in the North Carolina Medicaid program; the first reduced prescription lengths from 100 to 34 days' supply and the second increased copayments for brand name medications. Data Sources/Study Setting Medicaid claims data were obtained from the Centers for Medicare and Medicaid Services for January 1, 2000 – December 31, 2002. Study Design We used a pre-post controlled partial difference-in-difference-in-differences (DDD) design to examine the effect of the policy change on adults in North Carolina; adult Medicaid recipients from Georgia served as controls. Outcomes examined include medication adherence and Medicaid expenditures. Data Collection/Extraction Methods Data were aggregated to the person-quarter level. Individuals in HMOs, nursing homes, pregnant or deceased in the quarter were excluded. Principal Findings Both policies decreased medication adherence. The days' supply policy had a much larger effect on adherence than did the copayment increase. Total Medicaid spending declined from the days' supply policy but the copayment policy resulted in a net increase in Medicaid expenditures. Conclusions Although Medicaid costs decreased with the change in days supply policy, these savings were due to reduced adherence to these chronic medications. Additional research should examine the effect of these policy changes from the perspective of Medicaid enrollees.

Clinical effectiveness and cost-effectiveness of issuing longer versus shorter duration (3-month vs. 28-day) prescriptions in patients with chronic conditions: systematic review and economic modelling

“…49 The most common clinical classes evaluated were lipid-lowering agents, The study periods ranged from 3 months 46 to 7 years; 37 only one study was conducted over a period of less than 1 year, 46 six studies were conducted over a 12-month period 32,36,42,43,45,47 and eight studies were conducted over a period of more than 1 year. 35,37,[39][40][41]44,48,49 Ryvkin et al 38 did not report the length of their study. The most common outcomes measured were adherence, 35,36,39,40,[43][44][45]47 wastage 32,36,38,41,42,45,46,48 and costs.…”

“…Of the 16 included studies, nine were retrospective cohorts (six described as such by the study authors 32,37,39,40,45,48 and three classified as such by the reviewers 35,36,38 ), two were retrospective pre-post studies (one so described by the authors, 44 the other defined as such by the reviewers 41 ), three were cross-sectional studies (two described as such by the authors, 42,47 the other so defined by the reviewers 43 ) and two were cost analyses (both defined as such by the reviewers). 46,49 In addition, the authors of one of the retrospective cohort studies 45 and of one of the retrospective pre-post studies 44 undertook a cost-consequences analysis. In the vast majority of the studies, the authors undertook a secondary data analysis of pharmacy claims data.…”

“…38,40,47 The remaining four studies considered (1) 30 days' versus 60 days' supply, 39 (2) 100 days' versus 34 days' supply, 44 (3) 90 days versus < 90 days' supply 37 and (4) prescription lengths of ≤ 90 days. 43 The number of medications examined in a single study ranged from one 40 to 'any medication for a chronic condition'.…”

“…The most common outcomes measured were adherence, 35,36,39,40,[43][44][45]47 wastage 32,36,38,41,42,45,46,48 and costs. 42,[44][45][46]49 When the study design was not reported 35,36,38,43,46 or was unclear, 41,49 the design was classified by three reviewers (JE, SK and CMiani) based on the information presented, and guided by the NICE algorithm for classifying quantitative study designs. 50 No RCTs were identified.…”

“…42 Half of the studies specified the insurance scheme that patients were enrolled in: two (US) studies included predominantly indigent populations (adults who do not have health insurance and are not eligible for Medicaid, Medicare or private health insurance), 39,43 two studies were conducted among Medicaid patients, 44,45 four studies were set in Veterans Health Administrations 37,40,42,46 and one study used data from Kaiser Permanente health-care delivery sites. 47 All of the studies were conducted in the USA.…”