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© Managed Care &Healthcare Communications, LLC

Medicare Part D began in January of 2006 with implementa-tion of the Medicare Prescription Drug Improvement and Modernization Act.1 The standard benefit has an initial

deductible followed by coinsurance up to a threshold. Those exceeding this threshold enter the “donut hole,” or coverage gap, where they are responsible for all medication costs until the catastrophic threshold is reached, beyond which the patient pays a reduced level of coinsur-ance. In 2006, 4% of plans provided coverage for branded drugs with-out a gap,2 but such plans ceased to exist after 2006.2,3

The cost-sharing features of Part D have been associated with re-duced adherence.4-8 Characteristics such as costly medications, a greater number of prescriptions, or higher total monthly drug expense have been associated with cost-coping behaviors.5,7 Patients with serious chronic illness such as osteoporosis (OP), rheumatoid arthritis (RA), and multiple sclerosis (MS) who are treated with biologic therapies, which can be expensive relative to other medications, might be at par-ticularly high risk for discontinuation in the gap. Our primary objective was, for a given medication, to compare persistence in Part D plans. At Humana, a large benefits company, plans were offered in 2006 either with or without a coverage gap, which allowed us the unique opportu-nity to compare persistence between these 2 plan designs.

METHODSStudy Design and Patient Cohorts

This was a retrospective cohort study of beneficiaries enrolled in a Medicare Part D Prescription Drug Plan (PDP) through Humana. The institutional review board at the University of Miami (Florida) approved the study protocol. Two databases were linked to conduct the analysis. The first file contained enrollment and demographic information: age, gender, type of insurance, and geographic region for each beneficiary. The second file contained pharmaceutical claims data (frequency and cost) for each beneficiary.

Study cohorts were defined by medication usage, characteristics of which are defined in Table 1. Patients were required to have filled at

least 2 prescriptions of 1 of the study medications between January 1, 2006, and December 31, 2006. The medications were chosen to be representative of treatment for OP

Persistence With Biologic Therapies in the Medicare Coverage Gap

Leonardo Tamariz, MD, MPH; Claudia L. Uribe, MD, PhD; Jiacong Luo, MD, MPH;

John W. Hanna, MBA; Daniel E. Ball, DrPH; Kelly Krohn, MD; and Eric S. Meadows, PhD

Objectives: To describe persistence with teripara-tide and other biologic therapies in Medicare Part D plans with and without a coverage gap.

Study Design: Retrospective (2006) cohort study of Medicare Part D prescription drug plan benefi-ciaries from a large benefits company. Two plans with a coverage gap (defined as “basic”) were combined and compared with a single plan with coverage for generic and branded medications (defined as “complete”).

Methods: Patients taking alendronate (nonbiolog-ic comparator), teriparatide, etanercept, adalim-umab, interferon β-1a, or glatiramer acetate were selected for the study. For patients with complete coverage, equivalent financial thresholds were used to define the “gap.” The definition of discon-tinuation was failure to fill the index prescription after reaching the gap.

Results: For alendronate, 27% of 133,260 patients had enrolled in the complete plan. Patients taking biologic therapies had more commonly enrolled in complete plans: teriparatide (66% of 6221), etanercept (58% of 1469), adalimumab (52% of 824), interferon β-1a (60% of 438), and glatiramer acetate (53% of 393). For patients taking either alendronate or teriparatide, discontinuation rates were higher in the basic, versus complete, plan (adjusted odds ratios, 2.02 and 3.56, respectively). Discontinuation did not significantly vary by plan type for etanercept, adalimumab, interferon β-1a, or glatiramer acetate.

Conclusions: For patients who reached the coverage gap, discontinuation was more likely for patients taking osteoporosis (OP) medication. Not having a coverage gap was associated with improved persistence with OP treatment.

(Am J Manag Care. 2011;17(11):753-759)

For author information and disclosures, see end of text.

In this article Take-Away Points / p754 www.ajmc.com Full text and PDF

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(alendronate, teriparatide), RA (etanercept, adalimumab), or MS (interferon β-1a, glatiramer acetate). Eli Lilly, the manu-facturer of teriparatide, was interested in assessing adherence to teriparatide during the Medicare coverage gap in a real-world setting. Alendronate was selected as a nonbiologic compara-tor to teriparatide to evaluate adherence during the coverage gap for an OP medication with oral administration and poten-tially lower out-of-pocket (OOP) expenses. The other medica-tions are injectable biologics used for other disease states, but like teriparatide, could be associated with high OOP expenses during the coverage gap, and therefore were also included. The within-medication, between-plan comparisons of persistence were of primary interest. Comparisons of persistence between different medications were only descriptive and should be con-sidered exploratory.

Definition of the Medicare PlansIn 2006, Humana offered 3 stand-alone Medicare PDPs.

The 2 plans with a coverage gap differed somewhat in their plan designs (eg, one had higher premiums and a lower pa-tient cost per filled prescription) but were comparable on the characteristic of primary interest (having a gap). They were pooled in the analysis and are referred to as the “basic” plan. The plan without a gap in coverage for both generic and branded medications is described as the “complete” plan.

Therefore, for each medication, 1 cohort with and 1 cohort without a gap in cov-erage were available for analysis.

In 2006, the mandated Part D plan1 included cost-sharing or actuarially equivalent benefits according to the following basic format for individuals not receiving a low-income subsidy. Patients eligible for Medicaid or a low-income subsidy were excluded because

they did not experience a gap in coverage regardless of plan selection.

Deductible: Patient paid 100% up to $250 coinsurance: Patient paid 25% until an initial cov-

erage limit of $750 in total patient OOP spending ($2250 total drug costs)

Gap: No coverage between patient OOP costs of $750 ($2250 total drug costs) and $3600 ($5100 total drug costs)

catastrophic: Patient paid 5% of drug cost after OOP spending exceeded $3600 ($5100 total drug costs)

Definition of the Outcome Variable (Persistence)The date of a member’s first recorded claim for the index

medication was considered the index date. The number of days spent in each phase of Part D was tallied, beginning with the index date. The financial thresholds from the basic plan were assigned to the complete plan to create a “gap equivalent” for comparison purposes only. For example, $2250 was defined as the beginning of the “gap” phase for both the basic and com-plete patients even though the complete patients did not expe-rience an actual gap in coverage. Patients were excluded if they initiated the index medication after reaching the threshold due to the cost of medications other than the index medication.

Take-Away PointsFor patients who reached the coverage gap, discontinuation was more likely for patients taking osteoporosis medication:

n Not having a coverage gap was associated with improved persistence with osteoporo-sis treatment.

n Patients being treated for the symptomatic diseases of rheumatoid arthritis and mul-tiple sclerosis had no significant increase in discontinuation of therapy in the coverage gap.

n Health policy makers should be aware that a sudden increase in patient cost-sharing was associated with medication discontinuation for teriparatide.

n Table 1. Characteristics of the Medications Used to Define the Study Cohorts

Generic Name

Brand Name

Disease

Dose

Frequency

Route

Monthly Cost (US $)d

Alendronatea Fosamax OP and others 70 mg Weekly Oral 73

Teriparatide Forteob,c OP at high Fx risk 20 µg Daily SQ 635

Etanercept Enbrelc RA and others 50 mg Weekly SQ 1387

Adalimumab Humirac RA and others 40 mg Every 2 weeks SQ 1511

Interferon β-1a Avonex Relapsing-remitting MS 30 µg Weekly IM 1427

Glatiramer acetate Copaxone Relapsing-remitting MS 20 mg Daily SQ 1455

Fx indicates fracture; IM, intramuscular; MS, multiple sclerosis; OP, osteoporosis; RA, rheumatoid arthritis; SQ, subcutaneous. aAll products except alendronate are biologic therapies. bUse of Forteo for more than 2 years during a patient’s lifetime is not recommended. cUS package insert contains a boxed warning. dMonthly costs for 2006 were determined from the Humana data as total plan and patient paid amounts.

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lowing covariates: age, gender, CDS, pill burden, and calendar quarter of enrollment. All analyses were performed using SAS 8.0 (SAS Institute Inc, Cary, North Carolina). Significance tests were 2-sided at an alpha level of .05 unless otherwise noted. Two-sided P values based on 2 independent sample t tests were used for the comparison of the mean age between plans. Whenever the assumption of equality of variances was violated, the Satterthwaite method was used. Fisher exact test was used to compare gender and discontinuation between plans. Wilcoxon-Mann-Whitney test was used to compare the median of CDS and unique medications between plans. A 2-sided P value of .017 (Bonferroni-adjusted for multiple comparisons) was used to compare the median of number of days and OOP cost in each phase between plans (Wilcoxon-Mann-Whitney test).

RESULTSBaseline Characteristics

Demographic characteristics of the 142,605 patients in-cluded in the study are shown in Table 2. The mean ages of the OP, RA, and MS cohorts were approximately 56, 67, and 77 years, respectively. The vast majority of patients in every cohort was female. The RA cohort had the highest median CDS scores. Complete plan beneficiaries had higher CDS scores and more concomitant medication usage than basic plan beneficiaries. In the alendronate cohort, benefi-ciaries enrolled in the basic plan outnumbered those in the complete plan. In contrast, the reverse was true for the 5 biological therapies.

For each prescription, we used the fill date and the number of days supplied to calculate persistence. Discontinuation was defined as the absence of any index medication fills after enter-ing the gap. No maximum refill time window was required. To be considered eligible for discontinuation, patients had to reach the coverage gap or equivalent threshold and have filled at least 1 prescription for the index medication prior to doing so.

Evaluation of Possible ConfoundersPatient demographics included age, gender, chronic dis-

ease score (CDS), and pill burden. The CDS is a validated aggregate comorbidity measure in which disease severity and complexity are determined based on use of specific drug classes.9,10 Pill burden was quantified as the number of unique medications (identified by 10-digit Generic Product Identi-fiers) filled during the investigation period. Possible unmea-sured confounders are discussed as limitations.

Statistical AnalysisThe baseline characteristics of basic and complete mem-

bers were summarized by mean and standard deviation (SD) for age, percentages for gender, and median with interquartile ranges (IQR) for the CDS and pill burden. The number of patients beginning each phase, OOP cost during each phase, total days spent in each phase, and persistence were summa-rized by plan type for each drug. Multivariable logistic regres-sion models included lack of persistence (discontinuation after reaching the gap) as the outcome variable. Coverage during the gap (complete vs basic plan) was the independent variable of interest. The odds ratios were adjusted for the fol-

n Table 2. Demographics, Burden of Illness, and Medication Use in Patient Cohorts by Drug and by Plan Type

Drug

Plan Type

n

Age Mean, y (SD)

Female Gender, %

CDS Median (IQR)

Unique Meds Median (IQR)

Alendronate complete 36,635 77 (9)a 91a 4.3 (2.7)a 11 (7)a

basic 96,625 76 (8) 94 2.6 (2.1) 6 (6)

Teriparatide complete 4078 76 (8)a 93 3.9 (3.1)a 11 (9)a

basic 2143 77 (8) 94 3.5 (2.8) 9 (8)

Etanercept complete 857 66 (9) 70 5.0 (2.6)a 11 (9)a

basic 612 67 (10) 65 4.8 (2.7) 10 (8)

Adalimumab complete 425 67 (10)a 72 5.0 (2.7)a 11 (8)a

basic 399 68 (10) 73 4.6 (2.7) 10 (8)

Interferon β-1a complete 261 56 (10) 77 2.3 (2.9) 8 (10)

basic 177 57 (9) 80 2.3 (2.9) 7 (8)

Glatiramer acetate complete 210 55 (10) 77 2.7 (2.4) 9 (8)a

basic 183 55 (10) 80 2.5 (2.8) 7 (8)

CDS indicates chronic disease score; IQR, interquartile range; Meds, medications; SD, standard deviation; y, years. aStatistically significant differences between the basic and complete plans for a given medication at P <.05.

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Costs and Time in the Medicare PlanThe number of patients filling medication before, during,

and after the gap is shown in Table 3 along with the median number of days spent in each phase and corresponding OOP cost. With the complete plan, the financially equivalent thresholds are used to define the “gap” for comparison purpos-es. The median number of days before the coverage gap is sig-nificantly lower for individuals enrolled in complete plans for each medication cohort. Complete, versus basic, plan benefi-ciaries taking either of the 2 OP medications had more days in the coverage gap. Alendronate-treated patients spent less time in the catastrophic phase if they were enrolled in complete plans. Complete beneficiaries taking either of the OP medica-tions had significantly higher OOP costs before reaching the gap. For each medication cohort, patients in the complete plan had significantly lower OOP costs in the gap.

Effect of the Coverage Gap on DiscontinuationUnadjusted rates of discontinuation while in the gap are

shown in Table 4. Among patients taking RA or MS medi-cations, less than 10% discontinued their index medication after reaching the gap, regardless of plan type. Among pa-tients taking OP medications, discontinuation rates ranged from 8% to 35% depending on plan type and medication cohort. For patients in basic plans, discontinuation was sub-stantially higher than in the complete plan for patients tak-ing OP medications. After adjusting for covariates, patients

taking alendronate or teriparatide in the basic plan were twice as likely to discontinue as the controls in the complete plan (Figure).

DISCUSSIONThe Medicare Part D coverage gap was associated with

discontinuation among patients being treated with alendro-nate and especially teriparatide, a biologic OP therapy. For patients taking biologic therapy for RA or MS, no significant discontinuation was observed, but the smaller samples limited our ability to draw definitive conclusions for these cohorts. Overall, our finding that financial issues are associated with discontinuation but that nonfinancial factors also likely play an important role is consistent with previous reports.11,12

The majority of patients receiving biologic therapy had preferentially enrolled in the complete plan, which had a higher premium to help finance its enhanced benefits. The enrollment of these patients taking high-cost biologics sug-gests these patients were knowledgeable about their plan selection. However, any difference between the complete and basic plan cohorts beyond pharmacy utilization and de-mographics was unmeasured and is a study limitation. We included 6 different treatments across 3 diseases to minimize the likelihood of a single spurious result. The overwhelm-ing majority (97%) of Medicare patients who enrolled in a stand-alone PDP in 2006 elected a plan that did not offer

n Table 3. Number of Patients, Total Days Spent, and OOP Expenses by Phase According to Medication and Plan Type

n (before) % of n (in and catastr)

Median No. Days Spent in Each Phase

OOP Costa (US $)

Plan Type Beforeb Inc Catastrd Beforeb Inc Catastrd Beforeb Inc Catastrd

Alendronate complete 36,635 68 18 214e 113e 66e 130e 154e 225e

basic 96,625 18 2 275 74 74 96 277 149

Teriparatide complete 4078 91 62 120e 103e 90 103e 130e 168e

basic 2143 65 18 214 89 83 96 474 234

Etanercept complete 857 95 81 74e 60 153 187 369e 369e

basic 612 90 66 92 62 160 166 1039 264

Adalimumab complete 425 96 81 89e 58 154 155 376e 387e

basic 399 91 59 111 61 157 144 1037 253

Interferon β-1a complete 261 97 89 56e 56 187 232 397e 371e

basic 177 88 69 74 55 194 203 1147 228

Glatiramer acetate

complete 210 95 83 77e 59 188 189 390e 347e

basic 183 89 74 99 58 186 170 1198 209

Catastr indicates catastrophic; OOP, out-of-pocket. aMonthly OOP costs during each phase; does not include monthly premiums. bBefore reaching the coverage gap or equivalent threshold for plans without a gap; less than $2500 in total drug costs. cIn the gap or equivalent financial thresholds for plans without a gap; total drug costs between $2500 and $5100. dIn the catastrophic phase; total drug costs greater than $5100. eStatistically significant differences between the basic and complete plans for a given medication at P <.05.

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coverage of branded drugs in the gap,13 but for patients like those in this study (patients taking biologics or with an an-ticipated higher pill burden), the choice of a complete plan appears logical.

A detailed 2006 analysis of Part D plans reported that 94% of PDPs and 71% of Medicare Advantage with Pre-scription Drug (MA-PD) plans lacked coverage in the gap.13 The remaining plans offered coverage for generic (3% of PDPs and 22% of MA-PDs) and/or branded (3% of PDPs and 6% of MA-PDs) medications while in the gap. Of those patients enrolled in a complete plan, 52% were enrolled in Humana. Branded and generic coverage in the gap applied to just 3% of PDP enrollees over-all but accounted for 12% of Humana’s PDP enrollees.2 By 2008, no PDPs and only about 1% of MA-PDs offered full brand and generic coverage in the gap.13 In our analysis, most patients taking biologic therapy reached the coverage gap, and many, particularly those with RA and MS, exceeded the catastrophic threshold. With monthly costs that exceed $1300 for a single medication, patients taking RA or MS therapy reach catastrophic spending levels quite quickly. In comparison, only 18% of the alendronate basic cohort and 25% of patients in a generalized Medicare population with-out gap coverage reached the donut hole.2 Patients treated

with expensive biologic therapies clearly have special mon-etary challenges.

For patients taking the OP drugs, those in the basic, ver-sus complete, plan were much more likely to discontinue. However, even though their OOP cost would have exceeded $600 per refill, 75% of teriparatide patients in the basic plan persisted with treatment while in the gap. The unadjusted discontinuation rates seen after reaching the gap for the OP basic cohorts (25% for teriparatide and 35% for alendronate)

n Table 4. Discontinuation With Index Medication After Reaching the Gap or After Having Met the Equivalent Spending Threshold

Medication Plan Type

Discontinuation After Reaching Gap or Equivalent Threshold, n (%)

Alendronate complete 4956 (22%)a

basic 5837 (35%)

Teriparatide complete 230 (8%)a

basic 297 (25%)

Etanercept complete 33 (5%)

basic 29 (7%)

Adalimumab complete 24 (9%)

basic 19 (7%)

Interferon β-1a complete 15 (7%)

basic 11 (9%)

Glatiramer acetate complete 6 (4%)

basic 6 (5%)aStatistically significant differences between the basic and complete plans for a given medication at P <.05.

n Figure. Adjusteda Odds Ratio for Discontinuation With Index Medication After Reaching the Gap or After Having Met the Equivalent Spending Threshold

0.1 1

Adjusted Odds Ratio and 95% Confidence Intervalof Discontinuation

10

Alendronate

Teriparatide

Etanercept

Adalimumab

Interferon

Glatiramer0.35 2.470.95

0.74 3.341.57

0.39 1.250.71

0.76 1.891.2

2.99 4.233.56

1.93 2.112.02

aAdjusted for age, gender, chronic disease score, pill burden, and calendar quarter of enrollment.

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were somewhat higher than the 18% rate previously reported for OP medications.13 In prior work, we found that discontinu-ation was more common among teriparatide users than among beneficiaries with other chronic conditions with claims for hypertension and cholesterol medications.14 Another study across multiple disease states found that Medicare patients who reached the gap reduced their drug use by 17%.6

Reaching the gap without coverage was not associated with significantly increased discontinuation in patients with RA or MS. It should be noted that there were substantially fewer events (discontinuations) for the RA (<34) and MS (<16) cohorts, thereby limiting power to detect a difference between the complete and basic cohorts. Also, these patients were in the coverage gap an average of only 2 months, so the OOP costs would have been concentrated into this relatively short time frame. They would have spent more than $1300 out of pocket per prescription for the RA or MS medication in addition to the costs of any other concomitant medica-tions until they reached catastrophic coverage. Despite higher OOP costs for the patients taking RA or MS medications, their rates of discontinuation were generally lower than those of the teriparatide- or alendronate-treated patients.

The differences between patients with RA or MS and pa-tients with OP might be explained by the latter patients ex-periencing fewer physical symptoms than those with RA or MS. However, Briesacher et al showed that low adherence was observed for both OP (with alendronate) and the physically symptomatic disease gout (with allopurinol).15 It is worth not-ing that allopurinol is not associated with immediate relief of gout symptoms. Interestingly, other studies have found that co-payment increases in medications that treat symptoms, versus the underlying disease, were associated with larger reductions in medication utilization.16 In a study before the implementation of Part D, specialty medications for RA and MS were found to be largely insensitive to cost sharing.17 Another possible expla-nation is that while MS and RA are managed almost exclu-sively by neurologists and rheumatologists, respectively, OP is managed by a more heterogeneous group of generalists and spe-cialists whose overall approach to OP might be less aggressive.18 Also, patients with OP were older than their counterparts in the RA and MS cohorts, and factors such as lower income or a bias toward less aggressive care in older adults might partially explain our findings.19 In 2007, the median yearly income of individuals 75 years and older was two-thirds that of individuals 65 to 74 years of age.20 In a 2006 survey, roughly 5% of seniors and disabled individuals reported going without basic necessi-ties in order to pay for medication while in the gap.5 Clearly, difficult choices are being faced by patients who reach the gap and incur large OOP expenses. Some appear to be making sub-stantial sacrifices in order to continue treatment.

An important limitation is that the RA and MS cohorts were relatively small, which reduced our power, as noted above. Also, our study was based only on pharmacy claims data, with no associated medical records that would have allowed us to compare healthcare provider visits and hospi-talizations. The true indication for which a medication was prescribed was not available to us, nor was information regard-ing the clinical outcomes of patients who discontinued after reaching the gap. Furthermore, we did not know whether a decision to discontinue was made by the clinician or patient, and whether the decision was based on financial concerns or other factors not associated with the coverage gap. For ex-ample, side effects might contribute to discontinuation inde-pendently of financial issues. Nonadherence is common with chronic medications, and background discontinuation was probably present. Furthermore, patients could have switched therapies. Our primary interest was discontinuation of the in-dex medications, so we considered switching a relevant out-come, but our methodology simplified the actual situation. The complete plan served as an important control for the background discontinuation and switching limitations. An is-sue specific to teriparatide is that it is recommended for only 2 years of use per patient.21 Some patients could have completed 2 years of teriparatide while in the gap and discontinuation was a medical, rather than financial, decision. However, we expect that patients in the complete, versus basic, plan would have been at least as likely to reach the 2-year maximum in 2006. We hypothesize that in late 2005 or early 2006, teripa-ratide users would have been more likely to choose the com-plete plan to gain coverage within the gap.

Any patient in the study sample who discontinued filling prescriptions after reaching the gap might have continued therapy by using clinician-distributed samples or prescription assistance programs (PAPs), which could lead us to overes-timate the actual discontinuation rates.22 While we cannot be sure if use of samples or participation in PAPs would dif-fer by plan type, given the greater OOP burden in the gap for patients in the basic plan, we hypothesize that participa-tion would be greater among basic plan enrollees. One pos-sible refill pattern that we were unable to observe is restarting medications in 2007 after discontinuing in 2006, but we have found this to be uncommon.23 Our study was based exclusively on 2006 claims because the complete plan did not provide brand coverage during the gap in subsequent years. In the first year, 2006, that Medicare Part D was offered, patients could enroll without penalty through May.1 While a patient enroll-ing later in the year would have less time available to reach the gap, we controlled for a quarter of enrollment in the re-gression models and the patients typically reached the gap relatively quickly after initiating therapy. Even though a ran-

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domized study is probably not feasible, our observational study design limits our ability to conclude that the gap caused the discontinuation. While the recently enacted Patient Protection and Affordable Care Act24 includes provisions for discounts and then gradually eliminates the gap over the next decade, cost sharing might still be substantial. Even the standard 25% co-insurance rate can lead to high patient expenses with costly medications. Health policy makers need to understand the medication refill patterns during the original design and what the implications of more complete coverage are on utilization, patient care, and budgetary impact.

AcknowledgmentsAppreciation is expressed to Tamara Ball, MD, for editorial assistance.

Dr Ball is a scientific writer employed full-time by i3 Statprobe, a division of Ingenix, which is a subsidiary of UnitedHealth Group.

Author Affiliations: From Miller School of Medicine, University of Mi-ami, Miami, FL (LT); Competitive Health Analytics (CLU), Humana Health Services Research Center (JL, JWH), Humana Inc, Miramar, FL; Global Health Outcomes (DEB, ESM), Lilly USA (KK), Lilly Corporate Center, In-dianapolis, IN.

Funding Source: This study was funded by Eli Lilly and Company.Author Disclosures: Drs Meadows, Ball, and Krohn report employment

and stock ownership with Eli Lilly, manufacturer of teriparatide, one of the prescription medications included in this study. Dr Uribe reports employment with Competitive Health Analytics, Humana Inc, which was contracted by Eli Lilly for this study. The other authors (LT, JL, JWH) report no relationship or financial interest with any entity that would pose a conflict of interest with the subject matter of this article.

Authorship Information: Concept and design (ESM, LT, CLU, JL, JWH, DEB, KK); acquisition of data (LT, JL, JWH, KK); analysis and interpreta-tion of data (ESM, LT, CLU, JL, JWH, DEB, KK); drafting of the manuscript (ESM, JL, CLU, JWH, KK); critical revision of the manuscript for important intellectual content (ESM, LT, CLU, JWH, DEB, KK); statistical analysis (LT, JL); provision of study materials or patients (ESM); obtaining funding (LT, JWH); administrative, technical, or logistic support (JL, CLU); and supervi-sion (ESM, CLU).

Address correspondence to: Eric S. Meadows, PhD, MedMining, a Geis-inger Health System Business, 285 Mill St, Danville, PA 17822-4012. E-mail: esmeadows@geisinger.edu.

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