The economic burden of switching targeted disease-modifying anti-rheumatic drugs among rheumatoid arthritis patients

Aims: To estimate real world healthcare costs and resource utilization of rheumatoid arthritis (RA) patients associated with targeted disease modifying anti-rheumatic drugs (tDMARD) switching in general and switching to abatacept specifically.

Materials and methods: RA patients initiating a tDMARD were identified in IMS PharMetrics Plus health insurance claims data (2010–2016), and outcomes measured included monthly healthcare costs per patient (all-cause, RA-related) and resource utilization (inpatient stays, outpatient visits, emergency department [ED] visits). Generalized linear models were used to assess (i) average monthly costs per patient associated with tDMARD switching, and (ii) among switchers only, costs of switching to abatacept vs tumor necrosis factor inhibitors (TNFi) or other non-TNFi. Negative binomial regressions were used to determine incident rate ratios of resource utilization associated with switching to abatacept.

Results: Among 11,856 RA patients who initiated a tDMARD, 2,708 switched tDMARDs once and 814 switched twice (to a third tDMARD). Adjusted average monthly costs were higher among patients who switched to a second tDMARD vs non-switchers (all-cause: $4,785 vs $3,491, p?p?p?p?=?.021), and numerically lower all-cause costs ($4,444 vs $4,741, p?=?0.188). Switchers to TNFi relative to abatacept had more frequent inpatient stays after switch (incidence rate ratio (IRR) = 1.85, p?=?.031), and numerically higher ED visits (IRR = 1.32, p?=?.093). Outpatient visits were less frequent for TNFi switchers (IRR = 0.83, p?Limitations and conclusions: Switching to another tDMARD was associated with higher healthcare costs. Switching to abatacept, however, was associated with lower RA-related costs, fewer inpatient stays, but more frequent outpatient visits compared to switching to a TNFi.     

A real-world analysis of healthcare costs and relative risk of hyperprolactinemia associated with antipsychotic treatments in the United States

Abstract

Aims: Antipsychotic medications are associated with an increased risk of hyperprolactinemia, but differ in their propensity to cause this complication. This study aimed to assess the economic burden of hyperprolactinemia, and to compare its risk among adult patients using atypical antipsychotics (AAs) with a mechanism of action associated with no/low vs high/moderate prolactin elevation.

Methods: This retrospective cohort study was based on US Commercial and Medicaid claims databases. Healthcare costs were compared between matched hyperprolactinemia and hyperprolactinemia-free cohorts using a two-part model. Risk of hyperprolactinemia was compared between patients receiving AAs with a mechanism of action associated with no/low (no/low prolactin elevation cohort) vs high/moderate prolactin elevation (high/moderate prolactin cohort) using logistic regression.

Results: In the commercially insured sample, compared to the hyperprolactinemia-free cohort (n?=?499), the hyperprolactinemia cohort (n?=?499) was associated with incremental total healthcare costs of $5,732 ($20,081 vs $14,349; p?=?.004), and incremental medical costs of $3,861 ($13,218 vs $9,357; p?=?.040), mainly driven by hyperprolactinemia-related costs. In the Medicaid-insured sample, compared to the hyperprolactinemia-free cohort, the hyperprolactinemia cohort was associated with incremental total healthcare costs of $10,773 ($30,763 vs $19,990; p?=?.004), and incremental medical costs of $9,246 ($20,859 vs $11,613; p?=?.004), mainly driven by hyperprolactinemia-related and mental health-related costs. The odds of hyperprolactinemia in the no/low prolactin elevation cohort were 4–5-times lower than that in the high/moderate prolactin elevation cohort (odds ratio =0.21; p?<?.001).

Limitations: Hyperprolactinemia may be under-reported in claims data.

Conclusions: Hyperprolactinemia is associated with substantial healthcare costs. AAs associated with no/low prolactin elevation reduce the risk of hyperprolactinemia by 4–5-times compared to AAs associated with moderate/high prolactin elevation. Treatment options with minimal impact on prolactin levels may contribute to reducing hyperprolactinemia burden in AA-treated patients.     

Healthcare costs of urinary tract infections and genital mycotic infections among patients with type 2 diabetes mellitus initiated on canagliflozin: a retrospective cohort study

Objective: To assess the economic impact of urinary tract infections (UTIs) and genital mycotic infections (GMIs) among patients with type 2 diabetes mellitus (T2DM) initiated on canagliflozin.

Methods: Administrative claims data from April 2013 through June 2014 MarketScan^® databases were extracted. Adults with ≥1 claim for canagliflozin, T2DM diagnosis, and ≥90 days enrollment before and after canagliflozin initiation were propensity score matched to controls with T2DM initiated on other anti-hyperglycemic agents (AHAs). UTI and GMI healthcare costs were evaluated 90-days post-index and reported as cohort means.

Results: Rates of UTI claims 90 days post-index were similar in patients receiving canagliflozin for T2DM (n?=?31,257) and matched controls (2.7% vs 2.8%, p?=?.677). More canagliflozin than control patients had GMI claims (1.2% vs 0.6%, p?p?p?=?.150). GMI treatment costs were higher for the canagliflozin cohort ($3.68 vs $2.44, p?=?.041). Combined costs to treat either UTI and/or GMI averaged $31.29 per patient for the canagliflozin cohort v $39.77 for controls (p?=?.211). Rates and costs of UTIs and GMIs were higher for females than males, but the canagliflozin vs control trends observed for the overall sample were similar for both sexes. There were no significant cost differences between the canagliflozin and control cohorts among patients aged 18–64. Among patients aged 65 and above, GMI treatment costs were not significantly different, but costs to treat UTIs and either UTI and/or GMI were significantly lower for canagliflozin patients vs controls.

Conclusions: In a real-world setting, the costs to payers of treating UTIs and GMIs are generally similar for patients with T2DM initiated on canagliflozin vs other AHAs.     

Treatment patterns and healthcare costs among newly-diagnosed patients with chronic myeloid leukemia receiving dasatinib or nilotinib as first-line therapy in the United States

Objective: To compare treatment patterns and economic outcomes of dasatinib and nilotinib as 1st-line therapies for chronic myeloid leukemia (CML).

Methods: Adult CML patients initiated on first-line dasatinib or nilotinib in 2010–2014 were identified from two large US administrative claims databases. Treatment patterns, tyrosine kinase inhibitor (TKI) adherence and healthcare resource utilization (HRU) and costs were measured from the 1st-line TKI initiation (index date) to the end of follow-up.

Results: A total of 604 and 418 patients were included in the dasatinib and nilotinib cohorts (mean ages = 50.9 and 52.5 years, 46.4% and 45.7% female), respectively. Among the dasatinib patients, 91% started with 100?mg/day, 3% with <100?mg/day, and 6% with >100?mg/day. Among the nilotinib patients, 76% started with 600?mg/day, 16% with >600?mg/day, and 8% <600?mg/day. The dasatinib cohort had a higher hazard of dose decrease (hazard ratio [HR]?=?1.66; p?=?.002) and of switching to another TKI (HR =1.62; p?=?.019) compared to the nilotinib cohort. The hazard of dose increase (HR =0.76; p?=?.423) and treatment discontinuation (HR =1.10; p?=?.372) were not significantly different between cohorts. There was also no significant difference in TKI adherence levels (mean proportion of days covered [PDC] difference over first 6 months = ?0.0003, p?=?.981; mean PDC difference over first 12 months = ?0.0022, p?=?.880) and HRU (inpatient day incidence rate ratio [IRR]?=?1.03, p?=?.930; emergency room IRR =1.26, p?=?.197; and days with outpatient services IRR = 1.01, p?=?.842). The dasatinib cohort incurred higher healthcare costs by $749 per patient per month (p?=?.044) compared to the nilotinib cohort.

Limitation: Information on CML phase and Sokal score was not available.

Conclusions: Dasatinib was associated with an increased hazard of dose decrease and switching to another TKI and higher healthcare costs, vs nilotinib.     

Cost-effectiveness of subdermal implantable buprenorphine versus sublingual buprenorphine to treat opioid use disorder

Aims: Subdermal implantable buprenorphine (BSI) was recently approved to treat opioid use disorder (OUD) in clinically-stable adults. In the pivotal clinical trial, BSI was associated with a higher proportion of completely-abstinent patients (85.7% vs 71.9%; p?=?.03) vs sublingual buprenorphine (SL-BPN). Elsewhere, relapse to illicit drug use is associated with diminished treatment outcomes and increased costs. This study evaluated the cost-effectiveness of BSI vs SL-BPN from a US societal perspective.

Methods: A Markov model simulated BSI and SL-BPN cohorts (clinically-stable adults) transiting through four mutually-exclusive health states for 12 months. Cohorts accumulated direct medical costs from drug acquisition/administration; treatment-diversion/abuse; newly-acquired hepatitis-C; emergency room, hospital, and rehabilitation services; and pediatric poisonings. Non-medical costs of criminality, lost wages/work-productivity, and out-of-pocket expenses were also included. Transition probabilities to a relapsed state were derived from the aforementioned trial. Other transition probabilities, costs, and health-state utilities were derived from observational studies and adjusted for trial characteristics. Outcomes included incremental cost per quality-adjusted-life-year (QALY) gained and incremental net-monetary-benefit (INMB). Uncertainty was assessed by univariate and probabilistic sensitivity analysis (PSA).

Results: BSI was associated with lower total costs (?$4,386), more QALYs (+0.031), and favorable INMB at all willingness-to-pay (WTP) thresholds considered. Higher drug acquisition costs for BSI (+$6,492) were outpaced, primarily by reductions in emergency room/hospital utilization (?$8,040) and criminality (?$1,212). BSI was cost-effective in 89% of PSA model replicates, and had a significantly higher NMB at $50,000/QALY ($20,783 vs $15,007; p?Conclusions: BSI was preferred over SL-BPN from a health-economic perspective for treatment of OUD in clinically-stable adults. These findings should be interpreted carefully, due to some relationships having been modeled from inputs derived from multiple sources, and would benefit from comparison with outcomes from studies that employ administrative claims data or a naturalistic comparative design.     

Major bleeding risk and healthcare economic outcomes of non-valvular atrial fibrillation patients newly-initiated with oral anticoagulant therapy in the real-world setting

Aims: This study compared the risk for major bleeding (MB) and healthcare economic outcomes of patients with non-valvular atrial fibrillation (NVAF) after initiating treatment with apixaban vs rivaroxaban, dabigatran, or warfarin.

Methods: NVAF patients who initiated apixaban, rivaroxaban, dabigatran, or warfarin were identified from the IMS Pharmetrics Plus database (January 1, 2013–September 30, 2015). Propensity score matching (PSM) was used to balance differences in patient characteristics between study cohorts: patients treated with apixaban vs rivaroxaban, apixaban vs dabigatran, and apixaban vs warfarin. Risk of hospitalization and healthcare costs (all-cause and MB-related) were compared between matched cohorts during the follow-up.

Results: During the follow-up, risks for all-cause (hazard ratio [HR]?=?1.44, 95% confidence interval [CI]?=?1.2–1.7) and MB-related (HR?=?1.57, 95% CI?=?1.0–2.4) hospitalizations were significantly greater for patients treated with rivaroxaban vs apixaban. Adjusted total all-cause healthcare costs were significantly lower for patients treated with apixaban vs rivaroxaban ($3,950 vs $4,333 per patient per month [PPPM], p?=?.002) and MB-related medical costs were not statistically significantly different ($100 vs $233 PPPM, p?=?.096). Risk for all-cause hospitalization (HR?=?1.98, 95% CI?=?1.6–2.4) was significantly greater for patients treated with dabigatran vs apixaban, although total all-cause healthcare costs were not statistically different. Risks for all-cause (HR?=?2.22, 95% CI?=?1.9–2.5) and MB-related (HR?=?2.05, 95% CI?=?1.4–3.0) hospitalizations were significantly greater for patients treated with warfarin vs apixaban. Total all-cause healthcare costs ($3,919 vs $4,177 PPPM, p?=?.025) and MB-related medical costs ($96 vs $212 PPPM, p?=?.026) were significantly lower for patients treated with apixaban vs warfarin.

Limitations: This retrospective database analysis does not establish causation.

Conclusions: In the real-world setting, compared with rivaroxaban and warfarin, apixaban is associated with reduced risk of hospitalization and lower healthcare costs. Compared with dabigatran, apixaban is associated with lower risk of hospitalizations.     

Economic outcomes of exenatide vs liraglutide in type 2 diabetes patients in the United States: results from a retrospective claims database analysis

Abstract

Objective:

The safety and efficacy of the GLP-1 receptor agonists exenatide BID (exenatide) and liraglutide for treating type 2 diabetes mellitus (T2DM) have been established in clinical trials. Effective treatments may lower overall treatment costs. This study examined cost offsets and medication adherence for exenatide vs liraglutide in a large, managed care population in the US.

Methods:

This was a retrospective cohort analysis comprising adult patients with T2DM who initiated exenatide or liraglutide between 1/1/2010 and 6/30/2010 and had 6 months pre-index and post-index continuous eligibility. Patients were propensity score-matched to controls for baseline differences. Medication adherence was measured by proportion of days covered (PDC). Paired t-test and McNemar’s test were used to compare outcomes.

Results:

Matched exenatide and liraglutide cohorts (n?=?1347 pairs) had similar average total 6-month follow-up costs ($6688 vs $7346). However, exenatide patients had significantly lower mean pharmacy costs ($2925 vs $3272, p?<?0.001). Among liraglutide patients, patients receiving the 1.8?mg dose had significantly higher average total costs compared to those receiving the 1.2?mg dose ($8031 vs $6536, p?=?0.026), with higher mean pharmacy costs in the 1.8?mg cohort ($3935 vs $3146, p?<?0.001). There were no significant differences in inpatient or outpatient costs or medication adherence between groups (mean PDC: exenatide 56% vs liraglutide 57%, p?=?0.088).

Limitations:

The study assumed that all information needed for case classification and matching of cohorts was present and not differential across cohorts. The study did not control for covariates that were unavailable, such as HbA1c and duration of diabetes.

Conclusions:

Patients initiating exenatide vs liraglutide for T2DM had similar medication adherence and total healthcare costs; however, exenatide patients had significantly lower total pharmacy costs. Patients prescribed 1.8?mg liraglutide had significantly higher costs compared to those on 1.2?mg.     

Comorbidity and economic burden among moderate-to-severe psoriasis and/or psoriatic arthritis patients in the US Department of Defense population

Aims: To examine the comorbidity and economic burden among moderate-to-severe psoriasis (PsO) and/or psoriatic arthritis (PsA) patients in the US Department of Defense (DoD) population.

Materials and methods: This retrospective cohort claims analysis was conducted using DoD data from November 2010 to October 2015. Adult patients with ≥2 diagnoses of PsO and/or PsA (cases) were identified, and the first diagnosis date from November 2011 to October 2014 was defined as the index date. Patients were considered moderate-to-severe if they had ≥1 non-topical systemic therapy or phototherapy during the 12 months pre- or 1 month post-index date. Patients without a PsO/PsA diagnosis during the study period (controls) were matched to cases on a 10:1 ratio based on age, sex, region, and index year; the index date was randomly selected. One-to-one propensity score matching (PSM) was conducted to compare study outcomes in the first year post-index date, including healthcare resource utilization (HRU), costs, and comorbidity incidence.

Results: A total of 7,249 cases and 72,490 controls were identified. The mean age was 48.1 years. After PSM, comorbidity incidence was higher among cases, namely dyslipidemia (18.3% vs 13.5%, p?<?.001), hypertension (13.8% vs 8.7%, p?<?.001), and obesity (8.8% vs 6.1%, p?<?.001). Case patients had significantly higher HRU and costs, including inpatient ($2,196 vs $1,642; p?<?.0016), ambulatory ($8,804 vs 4,642; p?<?.001), emergency room ($432 vs $350; p?<?.001), pharmacy ($6,878 vs $1,160; p?<?.001), and total healthcare costs ($18,311 vs $7,795; p?<?.001).

Limitations: Claims data are collected for payment purposes; therefore, such data may have limitations for clinical research.

Conclusions: During follow-up, DoD patients with moderate-to-severe PsO and/or PsA experienced significantly higher HRU, cost, and comorbidity burden.     

One-year follow-up healthcare costs of patients hospitalized for transient ischemic attack or ischemic stroke and discharged with aspirin plus extended-release dipyridamole or clopidogrel

Abstract

Objective:

To examine healthcare costs among patients hospitalized for transient ischemic attack or ischemic stroke (TIA/stroke) and prescribed aspirin plus extended-release dipyridamole (ASA-ERDP) or clopidogrel (CLOPID) within 30 days post-discharge using a retrospective claims database from a large US managed care organization.

Methods:

Adult patients with ≥1 hospitalizations for TIA/stroke between January 2007–July 2009 and ≥1 claims for an oral anti-platelet (OAP) were observed for 1 year before and after the first TIA/stroke hospitalization or until death, whichever came first. Cohorts were defined by the first claim for ASA-ERDP or CLOPID within 30 days post-discharge. A generalized linear model, adjusting for demographics, baseline comorbidities and costs, compared total follow-up costs (medical?+?pharmacy) between ASA-ERDP and CLOPID patients.

Results:

Of 6377 patients (2085 ASA-ERDP; 4292 CLOPID) who met the selection criteria, mean (SD) age was 69 (13) years and 50% were male. Unadjusted mean total follow-up costs were lower for ASA-ERDP than CLOPID ($26,201 vs $30,349; p?=?0.002), of which average unadjusted medical and pharmacy costs were $22,094 vs $26,062 (p?=?0.003) and $4107 vs $4288 (p?=?0.119), respectively. Multivariate modeling indicated that the following were associated with higher total costs (all p?<?0.05): higher baseline Quan-Charlson comorbidity score, history of atrial fibrillation and myocardial infarction, index stroke hospitalization, death post-discharge, and index CLOPID use. Adjusted mean total follow-up costs for CLOPID were 9% higher than ASA-ERDP (cost ratio: 1.09; p?=?0.038).

Conclusion:

In this study, compared to CLOPID patients, ASA-ERDP patients were observed to have lower total costs 1 year post-discharge TIA/stroke hospitalization, driven primarily by lower medical costs. Further research into the real-world impact of OAP therapies on clinical and economic outcomes of patients with stroke/TIA is warranted. The findings of this study should be considered within the limitations of an administrative claims analysis, as claims data are collected for the purpose of payment.     

Brain metastases in non-small cell lung cancer patients on epidermal growth factor receptor tyrosine kinase inhibitors: symptom and economic burden

Objective: This study describes the symptom and economic burden associated with brain metastases (BM) in patients with non-small cell lung cancer (NSCLC) receiving epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (EGFR-TKIs).

Methods: This retrospective study included adults with ≥2 medical claims, within 90 days, for lung cancer and ≥1 administration of EGFR-TKIs. Based on ICD-9 codes, patients were stratified into cohorts by type of metastases (BM, other metastases [OM], or no metastases [NM]), and by when the metastasis diagnosis occurred (synchronous or asynchronous).

Results: The population (synchronous BM [SBM]?=?24, synchronous OM [SOM]?=?23, asynchronous BM [ASBM]?=?15, asynchronous OM [ASOM]?=?49, NM?=?85) was mostly female (57%), average age 69 years (SD?=?11). SBM patients experienced more fatigue and nausea/vomiting compared with SOM and NM patients and more headaches and loss of appetite than NM patients. ASBM was associated with more fatigue, nausea/vomiting, headaches, pain/numbness, altered mental status, and seizures than NM, and more headaches and pain/numbness than ASOM. SBM patients experienced a greater increase in per-member-per-month all-cause total healthcare costs after diagnosis ($20,301) vs SOM ($9,131, p?=?.001) and NM ($2,493, p?=?.001). ASBM’s cost increase between baseline and follow-up ($7,867) did not differ from ASOM’s ($4,947, p?=?.195); both were larger than NM ($2,493, p?=?.001 and p?=?.009, respectively).

Limitations: EGFR mutation status was inferred based on EGFR-TKI treatment, not by molecular testing. Patients were from US commercial insurance plans; results may not be generalizable to other populations.

Conclusions: Among patients with EGFR-TKI-treated NSCLC, patients with BM experienced more symptoms and, when diagnosed synchronously, had significant increases in total medical costs vs patients with OM and NM. Therapeutic options with central nervous system activity may offer advantages in symptomatology and costs in EGFR-mutated patients with BM.     

Burden of illness associated with sinusoidal obstruction syndrome/veno-occlusive disease in patients with hematopoietic stem cell transplantation

Aims: Sinusoidal obstruction syndrome (SOS) is a life-threatening complication of hematopoietic stem cell transplantation (HSCT) associated with significant morbidity and mortality. Healthcare utilization, costs, and mortality were assessed in HSCT patients diagnosed with SOS, with and without multi-organ dysfunction (MOD).

Materials and methods: This retrospective observational study identified real-world patients undergoing HSCT between January 1, 2009 and May 31, 2014 using the Premier Healthcare Database. In absence of a formal ICD-9-CM diagnostic code, SOS patients were identified using a pre-specified definition adapted from Baltimore and Seattle criteria and clinical practice. Severe SOS (SOS/MOD) and non-severe SOS (SOS/no-MOD) were classified according to clinical evidence for MOD in the database.

Results: Of the 5,418 patients with a discharge diagnosis of HSCT, 291 had SOS, with 134 categorized as SOS/MOD and 157 as SOS/no-MOD. The remaining 5,127 patients had HSCT without SOS. Overall SOS incidence was 5.4%, with 46% having evidence of MOD. Distribution of age, gender, and race were similar between the SOS cohorts and non-SOS patients. After controlling for hospital profile and admission characteristics, demographics, and clinical characteristics, the adjusted mean LOS was 31.0 days in SOS/MOD compared to 23.9 days in the non-SOS cohort (medians?=?26.9 days vs 20.8 days, p?p?Limitations: Limitations of retrospective observational studies apply, since the study was not randomized. Definition for SOS was based on ICD-9 diagnosis codes from a hospital administrative database and reliant on completeness and accuracy of coding.

Conclusions: Analysis of real-world data shows that SOS/MOD is associated with significant increases in healthcare utilization, costs, and inpatient mortality.     

The economic burden of end-of-life care in metastatic breast cancer

Objective: To assess end-of-life (EOL) total healthcare costs and resource utilization during the last 6 months of claims follow-up among patients with metastatic breast cancer (MBC) who received systemic anti-neoplastic therapy.

Methods: Newly diagnosed females with MBC initiating treatment January 1, 2003–June 30, 2011 were identified in a large commercial claims database. Two cohorts were defined based on a proxy measure for EOL 1 month prior to the end of last recorded follow-up within the study period: patients who were assumed dead at end of claims follow-up (EOL cohort) and patients who were alive (no-end-of-life [NEOL] cohort). Proxy measures for EOL were obtained from published literature and clinical expert opinion. Cost and resource utilization were evaluated for the 6 months prior to end of claims follow-up. Baseline variables, resource utilization, and costs were compared between cohorts with univariate statistical tests. Adjusted relative risks were calculated for resource utilization measures. A covariate-adjusted generalized linear model evaluated 6-month total healthcare costs.

Results: Of the 3,878 females included, 18.5% (n?=?718) met the criteria for EOL. Mean observational time (MBC onset to end of claims follow-up) was shorter for the EOL cohort (EOL, 32 months vs NEOL, 35 months; p?p?2 times higher in the EOL cohort (p?Conclusions: Potential EOL presented a greater economic burden in the 6 months prior to death. EOL month-to-month costs increased precipitously in the last 2 months of life and were driven by acute inpatient care.     

Clinical comorbidities,treatment patterns,and direct medical costs of patients with osteoarthritis in usual care: a retrospective claims database analysis

Abstract

Objective:

Comorbidities and resource utilization among patients with osteoarthritis (OA) in clinical practice have been infrequently characterized. The purpose of this study was to examine comorbidities, pain-related pharmacotherapy, and direct medical costs of patients with OA in clinical practice.

Method:

This retrospective cohort analysis used medical and pharmacy claims data from the LifeLink? Database. OA patients (ICD-9-CM codes 715.XX) were matched (age, gender, and region) with individuals without OA. Comorbidities, pain-related pharmacotherapy, and direct medical costs (pharmacy, outpatient, inpatient, total) were examined for the calendar year 2008.

Results:

The sample consisted of 112,951 OA patients and 112,951 controls (mean age: 56.9 [SD?=?9.5] years; 62% female). Relative to controls, OA patients were significantly more likely (p?<?0.0001) to have comorbidities, including musculoskeletal (84.3 vs. 37.1%) and neuropathic pain (22.0 vs. 6.1%) conditions, depression (12.4 vs. 6.4%), anxiety (6.6 vs. 3.5%), and sleep disorders (11.9 vs. 4.2%). OA patients were significantly more likely (p?<?0.0001) to receive pain-related medications, including opioids (40.7 vs. 17.1%), NSAIDs (37.1 vs. 11.5%), tramadol (9.8 vs. 1.8%), and adjunctive medications for treating depression, anxiety, and insomnia. Mean [SD] total direct medical costs were more than two times higher among OA patients ($12,905 [$21,884] vs. $5099 [$13,855]; p?<?0.001) and median costs were more than three times higher ($6188 vs. $1879; p?<?0.0001). Study limitations include potential errors in coding and recording; overestimation of the comorbidity burden; inability to link condition of interest, OA, with prescribed medications; and possible underestimation of the true costs of OA, because indirect costs were not considered and the direct costs were from a third party payer (commercial insurance) perspective.

Conclusion:

The patient burden of OA was characterized by a high prevalence of comorbidities. The payer burden was also substantial, with significantly greater use of pain-related and adjunctive medications, and higher direct medical costs.