Observational study of the outcomes and costs of initiating maintenance therapies in patients with moderate exacerbations of COPD.

BACKGROUND: There are limited data describing patients with moderate COPD exacerbations and evaluating comparative effectiveness of maintenance treatments in this patient population. The study examined COPD patients with moderate COPD exacerbations. COPD-related outcomes were compared between patients initiating fluticasone propionate-salmeterol 250/50 mcg (FSC) vs anticholinergics (ACs) following a moderate COPD exacerbation. METHODS: This retrospective observational study used a large administrative claims database (study period: 2003-2009) to identify and describe patients with an initial, moderate COPD exacerbation. A descriptive analysis of patients with moderate COPD exacerbations was done evaluating maintenance treatment rates, subsequent COPD exacerbation rates, and COPD-related costs during a 1-year period. A cohort analysis compared COPD exacerbation rates and associated costs during a variable-length follow-up period between patients initiating maintenance therapy with FSC or ACs. COPD exacerbations were reported as rate per 100 patient-years, and monthly costs were reported (standardized to USD 2009). COPD exacerbation rates between cohorts were evaluated using Cox proportional hazards models, and costs were analyzed using generalized linear models with log-link and gamma distribution. RESULTS: 21,524 patients with a moderate COPD exacerbation were identified. Only 25% initiated maintenance therapy, and 13% had a subsequent exacerbation. Annual costs averaged $594 per patient. A total of 2,849 treated patients (FSC = 925; AC = 1,924) were eligible for the cohort analysis. The FSC cohort had a significantly lower rate of COPD exacerbations compared to the AC cohort (20.8 vs 32.8; P = 0.04). After adjusting for differences in baseline covariates, the FSC cohort had a 42% significantly lower risk of a COPD exacerbation (HR = 0.58; 95% CI: 0.38, 0.91). The FSC cohort incurred significantly higher adjusted pharmacy costs per patient per month by $37 (95% CI: $19, $72) for COPD-related medications vs the AC cohort. However, this increase was offset by a significant reduction in adjusted monthly medical costs per patient for the FSC vs the AC cohort ($82 vs $112; P < 0.05). Total monthly COPD-related costs, as a result, did not differ between cohorts. CONCLUSIONS: Only a quarter of patients with a moderate COPD exacerbation were subsequently treated with maintenance therapy. Initiation of FSC among those treated was associated with better clinical and economic outcomes compared to AC.

Short-acting ß-agonist use and its ability to predict future asthma-related outcomes.

BACKGROUND: Short-acting ß-agonist (SABA) use is well established in predicting asthma events in adults. However, this predictive ability has yet to be established in a pediatric population together with an assessment of amount of use. OBJECTIVE: To identify the number of SABA canisters that best predicts future asthma-related exacerbations and the optimal length of time for measurement of SABA use in pediatric and adult asthma patients. METHODS: Asthma patients were identified from a Medicaid and a commercially insured database (January 1, 2004, through December 31, 2005, and January 1, 2004, through June 30, 2006, respectively). Following the date of first asthma medication, an assessment period (3, 6, or 12 months) was used to measure SABA use. Asthma-related exacerbations were identified in the subsequent 12-month period. Receiver operating characteristic curve analyses and logistic regression were used to select the critical values of SABA use and optimal assessment periods and to conduct incremental analysis, respectively. RESULTS: A total of 33,793 Medicaid and 101,437 commercial patients met the study criteria. Use of 3 or more SABA canisters during 12 months was identified in both pediatric Medicaid and commercial populations to best predict an increased risk of an asthma-related exacerbation. For adults, use of 2 or more SABA canisters was found as the critical value with shorter optimal assessment periods of 3 and 6 months. Each additional SABA canister resulted in an 8% to 14% and 14% to 18% increase in risk of an asthma-related exacerbation in children and adults, respectively. CONCLUSION: The study identified critical values of SABA use that predict future asthma events. Each additional SABA canister predicted increases in exacerbation risk in children and adults.

Pitfalls in Fine-Needle Aspiration Cytology Diagnosis of Ductal Carcinoma in a Lactating Breast.

Breast undergoes hormonal changes, especially during pregnancy and postpartum period and may be associated with benign and malignant lesions. These lesions can arise either de novo or can be an exacerbated change occurring in a preexisting breast lesion. The benign lesion in the lactating breast can show some degree of atypia due to the high levels of progesterone and prolactin which can mimic malignant features microscopically and can be overdiagnosed with breast cancer. On the other hand, breast cancer in the lactating breast can be underdiagnosed when the atypical cytological features are considered as hormonal changes. A few case reports are published in the literature regarding lactating adenoma undergoing malignant transformation. We present a case in 23 years postpartum lactating female with mass in bilateral breasts. Initially, the lesions were diagnosed with hormonal changes on cytology. On follow-up by fine-needle aspiration cytology and biopsy, it was diagnosed with infiltrating ductal carcinoma in both breasts. As far as our knowledge goes, this is the first-case report in the English literature of ductal carcinoma in the bilateral lactating breast arising de novo.

The cost of treating the 10 most prevalent diseases in men 50 years of age or older.

OBJECTIVE: Costs of treating the 10 most prevalent diagnosed diseases in men > or = 50 years of age were examined in hopes of identifying areas for better medical management and opportunities to decrease healthcare costs. METHODS: A retrospective analysis of a large national managed care database was utilized to assess the costs of treating the 10 most diagnosed diseases in aging men. All men initiating pharmacy treatment between July 1, 1997, and January 31, 2003, for (1) hypertension; (2) coronary artery disease (CAD); (3) type 2 diabetes; (4) enlarged prostate; (5) osteoarthritis; (6) gastroesophageal reflux disease; (7) bursitis; (8) arrhythmias; (9) cataracts; and (10) depression were included. Patients were continuously followed 6 months before and 12 months after initiating treatment. Costs of treatment and likelihood of experiencing a significant event were examined. RESULTS: One-year total disease-specific medical costs were highest for arrhythmias, osteoarthritis, cataracts, and CAD. Total medical costs for bursitis, type 2 diabetes, and enlarged prostate were between $400 and $500. Inpatient costs as a percentage of total medical costs were highest for CAD (75%), osteoarthritis (61%), arrhythmias (57%), and enlarged prostate (40%). For most diseases, pharmacy charges were <50% of the total cost. The likelihood of experiencing a significant clinical event within 1 year of initiating treatment was highest in men with bursitis (23%, surgery) and enlarged prostate (19.2%, acute urinary retention and/or surgery), hypertension (13.5%), and diabetes (9.5%). CONCLUSION: The most costly conditions in the 10 most prevalent diseases in men > or = 50 years of age were typically those that required substantial inpatient care. Conditions such as enlarged prostate, diabetes, and hypertension demonstrated a high likelihood of a clinical event within 1 year of initiating treatment. These conditions are therapeutic areas with the greatest likelihood of improvement, given what is known about the use of appropriate pharmacotherapy and the likelihood of treating to goal. Proactive patient management (eg, initiating/maximizing pharmacotherapy) may have the potential to positively impact clinical and economic outcomes for aging men.

Antidepressant adherence and medical resource use among managed care patients with anxiety disorders.

OBJECTIVES: This study evaluated adherence with selective serotonin reuptake inhibitors (SSRIs) or serotonin-norepinephrine reuptake inhibitors (SNRIs) among patients who newly initiated therapy for anxiety with or without comorbid depression; the study also quantified the health-related economic consequences of nonadherence. METHODS: A large managed care database was used to gather retrospective data for patients with anxiety disorders who had a prescription for an antidepressant between July 1, 2001, and December 31, 2002. The relationship between antidepressant adherence and medical resource utilization was assessed; the analysis controlled for age, gender, utilization of mental health specialty care, change in medication, whether the dosage was titrated, costs in the six months before the prescription for an antidepressant, and comorbid physical conditions. RESULTS: Of the 13,085 patients with anxiety diagnoses who met the criteria for study inclusion, 57 percent were nonadherent to antidepressant therapy at six months. Patients who received mental health specialty care were more likely than those who did not receive such care to be adherent to therapy (48.5 percent compared with 40.7 percent; p<.001). Those with dual diagnoses of anxiety and depression were more likely than those with anxiety alone to be adherent to therapy (46.8 percent compared with 40.2 percent; p<.001). Those with a coded diagnosis of posttraumatic stress disorder had the highest medical costs. Patients with anxiety and depression had significantly higher total costs than patients with anxiety alone. Adherent patients who did not have a change in medication or a titrated dosage had significantly lower medical costs than nonadherent patients; however, total costs (medical plus pharmacy) were similar. CONCLUSIONS: Nonadherence with antidepressant therapy in anxiety disorders is common, but mental health specialty care may be associated with improved adherence. Lower medical costs for adherent patients who did not have a change in medication or a titrated dosage offset the increase in pharmacy costs, resulting in total costs (medical plus pharmacy) that were similar to those of nonadherent patients.

Differences in total medical costs across the SSRIs for the treatment of depression and anxiety.

There is growing evidence that adherence to the recommended duration of antidepressant therapy results in reduced medical costs compared with nonadherence, and that the likelihood of adhering to therapy is not equivalent across the selective serotonin reuptake inhibitors (SSRIs). As such, the purpose of this study was to assess differences in 6-month medical costs between paroxetine controlled-release (CR) and immediate-release (IR) SSRI agents in a retrospective analysis of patients initiating SSRI therapy identified from the Integrated Healthcare Information Services National Managed Care Benchmark Database during a 2.5-year time frame. Inferential analyses were performed to evaluate differences in 6-month medical costs, controlling for differences in age, sex, utilization of psychiatric specialty care services, titration, pre-period costs, and comorbidity measures. Of the 146 075 patients included in this study, approximately 7% received paroxetine CR. Approximately 29.5% of patients had an anxiety disorder diagnosis; 26.0% had a depression-only diagnosis; and 13.2% had comorbid anxiety and depression. The 6-month medical costs were 244 US dollars lower for patients initiating with paroxetine CR compared with the average medical costs for patients receiving IR SSRIs. Paroxetine CR also had the lowest medical costs compared with each individual SSRI evaluated. After log transformation of costs and adjustment for baseline covariates, the aggregated IR SSRIs were associated with 8.7% higher 6-month medical costs than paroxetine CR (P <.001) and even greater costs after stratifying by diagnosis: 12.5% higher costs in patients with anxiety, 14.3% higher costs in patients with depression, and 15.9% higher costs in patients with comorbid anxiety and depression (P <.001 for all). Each individual IR SSRI was also associated with significantly higher medical costs than paroxetine CR, irrespective of diagnosis. As demonstrated, medical costs over a 6-month time frame were significantly greater for IR SSRIs versus paroxetine CR, even after adjusting for background characteristics and stratifying by diagnosis. Future studies should measure rates of adherence in relation to medical outcomes over an expanded time frame.

Predicting asthma outcomes in commercially insured and Medicaid populations?

OBJECTIVES: To assess the predictive ability of the ratio of controller-to-total asthma medication in commercially insured and Medicaid patients. STUDY DESIGN: Retrospective cohort. METHODS: Medical and pharmacy claims were used to identify asthma patients between 2004 and 2006. Ratios were computed during 3-, 6-, and 12-month assessment periods and asthma exacerbations were assessed during a subsequent 12-month follow-up period. Receiver operating characteristic curve analyses and logistic regression were used to select optimal ratio number, assessment time period, and incremental ratio analysis. RESULTS: The ratio significantly predicted future asthma exacerbations. An optimal value of >0.7 was identified in pediatric and adult Medicaid patients with a shorter assessment period in adults (3 months) than in children (6 months). In commercially insured patients, an optimal value of >0.5 during a 6-month assessment period was identified for children and adults. In commercially insured patients, a 0.1-unit increase in the ratio below the 0.5 value resulted in a 72% (odds ratio [OR] 0.28; 95% confidence interval [CI] 0.13-0.57) and 80% (OR 0.20; 95% CI 0.12-0.33) risk reduction among pediatric and adult patients, respectively. Similarly, a 0.1-unit increase in the ratio below the 0.7 optimal value in the Medicaid population resulted in significant risk reduction in the pediatric (OR 0.65; 95% CI 0.43-0.97) but not the adult cohort. CONCLUSIONS: The ratio is a significant predictive risk marker in commercially insured and Medicaid asthma populations. Incremental risk reductions can be realized by unit increases in the ratio up to the identified optimal value.

Outcomes associated with timing of maintenance treatment for COPD exacerbation.

OBJECTIVES: To examine the impact of timing of maintenance treatment initiation (early vs delayed) on risk of future exacerbations and costs in chronic obstructive pulmonary disease (COPD) patients. STUDY DESIGN: Retrospective cohort design using data (January 1, 2003, through June 30, 2009) from a large, US-based integrated pharmacy and medical claims database. METHODS: Administrative claims from January 1, 2003, through June 30, 2009, were used. Methotrexate (MTx)-naïve patients (aged >40 years) with at least 1 COPD-related hospitalization/emergency department (ED) visit were included (discharge date was index date). Patients initiating MTx within the first 30 days and 31 to 180 days post-index were classified into early and delayed cohorts, respectively. Clinical and economic outcomes related to COPD exacerbations were assessed for 1 year post-index and compared between cohorts using regression models controlling for baseline characteristics. The incremental effect on outcomes of every 30-day delay in MTx initiation up to 6 months after the index event was also assessed. RESULTS: The majority of the 3806 patients (78.6%) received early MTx. A significantly higher proportion of patients in the delayed cohort had a COPD-related hospitalization/ED visit compared with the early cohort (25.6% vs 18.0%; P <.001). After controlling for baseline differences, the delayed cohort had a 43% (P <.001) higher risk of a future COPD-related hospitalization/ED visit compared with the early cohort. Every 30-day delay was associated with 9% risk increase (P = .002). Treatment delay also increased COPD-related costs ($5012 vs $3585; P <.001). CONCLUSION: Early MTx initiation is associated with reduced risk of future COPD exacerbations and lower costs.

The economic impact of delaying 5-alpha reductase inhibitor therapy in men receiving treatment for symptomatic benign prostatic hyperplasia.

BACKGROUND: Pharmacologic treatment of lower urinary tract symptoms associated with benign prostatic hyperplasia often includes alpha-blockers and 5-alpha reductase inhibitors. Many clinicians use alpha-blockers for rapid symptom control, later adding 5-alpha reductase inhibitors to modify long-term disease progression. Delaying the addition of these medications has been shown to result in reduced clinical outcomes. The economic impact of this practice has not been widely studied or reported to date. OBJECTIVE: The objective of this study was to assess the economic impact of delaying initiation of concomitant 5-alpha reductase inhibitor therapy (≥30 days) in patients receiving alpha-blockers for lower urinary tract symptoms. METHODS: Using 2 nationally representative databases (Integrated Health Care Information Solutions and PharMetrics), 2 retrospective analyses were conducted involving 2636 and 4260 men, respectively, aged ≥50 years treated for benign prostatic hyperplasia between 2000 and 2007. Economic outcomes (ie, the cost of therapy and the use of healthcare resources) were compared for adding 5-alpha reductase inhibitor therapy early (within <30 days of initiating an alpha-blocker) versus delaying these medications (≥30 days after initiating an alpha-blocker). RESULTS: In the Integrated Health Care Information Solutions analysis, patients in the early add-on therapy group (n = 1572) had lower benign prostatic hyperplasia-related medical costs in the posttreatment period than those in the delayed-therapy group (n = 1064), $349 versus $618 (P <.0001). Similar trends were seen in the PharMetrics analysis-the medical costs in the early add-on therapy group (n = 2604) and delayed group (n = 1656) were $344 versus $449, respectively (P <.001). Pharmacy costs were $1068 for the early-treatment cohort and $989 for the delayed-treatment cohort for the Integrated Health Care Information Solutions database, yielding total costs of $1417 and $1606, respectively, for a $189 savings per patient over the initial year of treatment (P <.0001). In the PharMetrics analysis, pharmacy costs were $1391 for the early-treatment cohort and $1237 for the delayed-treatment cohort, resulting in total cost of $1735 and $1686, respectively, yielding $59 in additional costs per patient annually for those treated early (P = .8645). CONCLUSION: These results suggest that patients receiving 5-alpha reductase inhibitor therapy within 30 days after initiating alpha-blocker treatment have lower benign prostatic hyperplasia-related medical costs than those who start combination treatment later. The increase in pharmacy costs associated with early initiation of 5-alpha reductase inhibitor therapy resulted in total costs that were similar or significantly lower than those of delayed combination users.

Impact of delaying 5-alpha reductase inhibitor therapy in men on alpha-blocker therapy to treat BPH: assessment of acute urinary retention and prostate-related surgery.

OBJECTIVE: Pharmacologic treatment of lower urinary tract symptoms from benign prostatic hyperplasia (BPH) commonly includes alpha-blockers (ABs) and 5alpha-reductase inhibitors (5ARIs). Many clinicians use ABs for rapid symptom control and 5ARIs to modify long-term disease progression. The purpose of this study was to assess the clinical impact of delayed 5ARI therapy in patients treated with AB for lower urinary tract symptoms. RESEARCH DESIGN AND METHODS: Using two nationally representative databases, two retrospective analyses were conducted including patients aged > or =50 years treated for BPH between 2000 and 2007. Clinical outcomes for those using add-on 5ARI therapy early (within 30 days of initiating AB) and late (>30 days after initiating AB) were compared. Likelihood of clinical progression, defined as the presence of acute urinary retention (AUR) and prostate surgery, was assessed over 1 year after AB initiation, and modeled as a function of the treatment cohorts and the following baseline covariates: AUR, BPH stage, Charlson Comorbidity Index, age, and number of unique diagnosis codes, unique non-BPH-related classes of prescriptions filled, and specialty care. RESULTS: Of 6896 men included in the analyses, approximately 60% initiated 5ARI therapy within 30 days of AB therapy (the early cohort). Patients in the early cohort were less likely to have clinical progression. Each 30-day delay in starting 5ARIs resulted in an increased likelihood of overall clinical progression (average 21.1%), AUR (average 18.6%), and prostate-related surgery (average 26.7%). CONCLUSIONS: These results suggest that delaying 5ARI therapy in men with BPH increases the risk of AUR and prostate surgery. LIMITATIONS: Confounding factors, such as symptom severity and prostate volume, may have influenced the findings of the study.

Dutasteride vs finasteride: assessment of differences in acute urinary retention rates and surgical risk outcomes in an elderly population aged > or =65 years.

OBJECTIVE: To determine comparative differences on rates of acute urinary retention (AUR) and prostate-related surgeries among patients aged > or =65 years treated with dutasteride or finasteride. METHODS: For this retrospective analysis, medical/pharmacy claims data from July 1, 2003, to June 30, 2006, were analyzed for enlarged prostate patients aged > or =65 years treated with 5-alpha reductase inhibitors (5ARIs) regardless of alpha-blocker use. Charlson Comorbidity Index, Thomson Medstat Disease Staging, and propensity score matching techniques were used for comparative analysis. RESULTS: A total of 5090 patients met selection criteria. After 1 year of 5ARI therapy, the AUR rate was lower for dutasteride (12%) when compared with finasteride (14.7%) (odds ratio [OR], 0.79; P = .0042). Risks for prostate-related surgeries were also lower among dutasteride-treated patients (3.9% vs 5.1%, respectively; OR, 0.77; P = .03). CONCLUSION: Important therapeutic outcome differences exist between dutasteride and finasteride. Patients treated with dutasteride were significantly less likely to experience AUR and prostate-related surgeries than finasteride patients.

Comparative analysis of alpha-blocker utilization in combination with 5-alpha reductase inhibitors for enlarged prostate in a managed care setting among Medicare-aged men.

OBJECTIVE: To evaluate the likelihood of alpha-adrenergic antagonist (alpha-blocker) discontinuation in combination with dutasteride or finasteride among patients aged > or =65 years with enlarged prostate. METHOD: This retrospective analysis used 2003-2006 data representing more than 30 million managed care members. Medical/pharmacy claims were used to select patients, matched 1:1 using propensity scoring. The proportion remaining on alpha-blocker therapy more than 12 months and time to discontinuation were compared between groups, controlling for covariates using survival analysis. RESULTS: The matched sample included 1674 patients. Alpha-blocker therapy discontinuation was observed at 90 days (86.9% dutasteride patients and 91.8% finasteride patients remained on alpha-blocker therapy). After 12 months, more dutasteride patients discontinued (38.1% remained) alpha-blocker therapy than finasteride patients (56.3% remained). CONCLUSIONS: Patients discontinued alpha-blocker therapy as early as 3 months. Those taking dutasteride were 64% more likely to discontinue alpha-blocker therapy than patients taking finasteride. Dutasteride's impact on discontinuation may have important implications and should be examined further.

Part 3: Endoscopic injection versus antibiotic prophylaxis in the reduction of urinary tract infections in patients with vesicoureteral reflux.

OBJECTIVE: Vesicoureteral reflux (VUR) occurs in approximately 1% of infants and children and is associated with recurrent urinary tract infections (UTIs). The objective of this paper is to examine the use of endoscopic injection with dextranomer/hyaluronic acid copolymer (Dx/HA) as a curative option and as an alternative to antibiotic prophylaxis, as Dx/HA is gaining in popularity in the treatment of VUR. METHODS: The nationally representative PharMetrics Integrated Medical and Pharmaceutical database was used to conduct this retrospective analysis. Patients < 11 years of age who were continuously eligible and had an International Classification of Diseases (ICD-9-CM) code for VUR were identified. Resource utilization and outcome measures were evaluated over a 6-month pre- and 12-month post-index period. Patients diagnosed with neuropathic bladder, posterior urethral valves, bladder exstrophy, ureterocele, or duplication anomaly were excluded. Patients were matched 3 : 1, antibiotic prophylaxis to Dx/HA, by age, gender, urinary tract infections (UTIs) prior to index date, and diagnosing physician specialty. The primary outcome assessed was UTIs. RESULTS: Of the matched patients, 114 received a prescription for antibiotic prophylaxis and 38 underwent endoscopic injection with Dx/HA between January 2000 and December 2004. The average number of UTIs per year was 0.28 in the antibiotic cohort and 0.08 in the Dx/HA cohort, respectively. The incidence rate ratio (IRR) of 4.826 (p = 0.029) revealed that the average number of UTIs was 383% higher for patients receiving antibiotic prophylaxis compared with patients who underwent endoscopic injection. The retrospective nature of the analysis did not allow for treatment randomization. Due to the stringent classification of UTIs, rates of UTIs may be underestimated in both cohorts. CONCLUSIONS: Treatment with endoscopic injection with Dx/HA resulted in significantly fewer UTIs compared with children receiving antibiotic prophylaxis, supporting a role for Dx/HA as a first-line treatment option for patients with VUR.

A large retrospective analysis of acute urinary retention and prostate-related surgery in BPH patients treated with 5-alpha reductase inhibitors: dutasteride versus finasteride.

OBJECTIVE: The purpose of this study was to examine the rates of acute urinary retention (AUR) and surgery after initiating 5-alpha reductase inhibitor (5ARI) therapy and to compare the 2 currently available 5ARIs, dutasteride and finasteride, in a real-world, managed care setting. This study constitutes the first direct comparison of therapeutic outcome between a mono 5ARI (finasteride) and a dual 5ARI (dutasteride). METHODS: This is a retrospective descriptive and comparative analysis of the rates of AUR and prostate surgery in patients with benign prostatic hyperplasia (BPH) treated with 5ARI therapy, either dutasteride or finasteride. Data were obtained from the PharMetrics Integrated Medical and Pharmaceutical Database (PIMPD) (Watertown, Mass) during a 6-year period. The PIMPD is a large national healthcare database that represents a total of 85 managed health plans and covers more than 45 million patients. The data analysis included all patients aged 50 years or older diagnosed with BPH who were treated with 5ARIs (dutasteride 0.5 mg/day or finasteride 5 mg/day) for up to 12 months during the 6-year period of January 1, 1999, to March 1, 2005. Patients meeting the selection criteria were evaluated for a total of 12 months with regard to the likelihood of experiencing AUR or prostate-related surgery. RESULTS: After 5 months of 5ARI therapy, the rate of AUR during months 5 to 12 was found to be significantly lower in the dutasteride group compared with the finasteride group (5.3% vs 8.3%). After controlling for background covariates, dutasteride-treated patients were 49.1% less likely to experience AUR than patients treated with finasteride (P = .0207). Patients treated with dutasteride were also less likely to undergo prostate-related surgery, with 1.4% of dutasteride treated patients and 3.4% of patients receiving finasteride undergoing surgery; differences in surgery rates, however, were not statistically significant (P = .0745), even after controlling for background covariates. CONCLUSTION: Although the 2 drugs, dutasteride and finasteride, belong to the same category of 5ARIs, this large retrospective multivariate analysis potentially indicates differences in therapeutic outcomes. In this study, patients treated with dutasteride were less likely to experience AUR and demonstrated a trend toward being less likely to experience surgery than patients treated with finasteride.

Methods for evaluating patient adherence to antidepressant therapy: a real-world comparison of adherence and economic outcomes.

OBJECTIVE: The objective of this study was to differentiate between 3 measures of antidepressant adherence with regard to the number of patients deemed adherent to therapy and the association between adherence and resource utilization. DESIGN AND SETTING: The authors conducted a retrospective study of patients initiating selective serotonin reuptake inhibitor (SSRI) therapy for depression and/or anxiety between July 2001 and June 2002 in a large national managed care database. MAIN OUTCOME MEASURES: Rates of 6-month SSRI adherence were measured by 3 different metrics: length of therapy (LOT), medication possession ratio (MPR), and combined MPR/LOT. Differences in resource utilization for each adherence metric were measured for patients deemed as 1) adherent, 2) nonadherent, 3) therapy changers, and 4) dose titraters. RESULTS: There were 22,947 patients meeting study criteria. Although statistically different, 6-month adherence rates were numerically similar across all methods (LOT, 44.6%; MPR, 43.3%; and MPR/LOT, 42.9%, P < 0.001); approximately 57% of patients were nonadherent to therapy. Regardless of metric, the adherent cohort incurred the lowest yearly medical costs, followed by the nonadherent, titrate, and therapy change cohorts (P < 0.001 between adherent cohort and all other cohorts). The LOT method produced the greatest difference in yearly medical costs between adherent and nonadherent patients (Dollars 511) followed by MPR/LOT (Dollars 432) and MPR (Dollars 423). When antidepressant prescription costs were added to medical costs, patients requiring a therapy change and titrating therapy incurred higher costs than adherent patients, whereas nonadherent and adherent patients incurred similar costs. CONCLUSION: Regardless of adherence metric, approximately 43% of patients were adherent to antidepressant therapy, and adherent patients were associated with the lowest yearly medical costs.