Health care utilization and costs in type 2 diabetes mellitus and their association with renal impairment.

OBJECTIVE: To evaluate the health economic burden of renal impairment (RI) in patients with type 2 diabetes mellitus (T2DM). METHODS: This retrospective analysis used medical and pharmacy claims and outpatient laboratory data from a large US health care plan (January 1, 2004 to December 31, 2008). Patients with T2DM aged ≥ 18 years with continuous enrollment for ≥ 12 months pre- and post-index date (defined as date of first evidence of T2DM) who had ≥ 1 serum creatinine (SCr) laboratory test in pre- and post-index periods were included. Renal impairment prevalence was determined by laboratory data and compared with prevalence of RI identified from claims (physician-diagnosed). Renal impairment stages were categorized using estimated glomerular filtration rate. Multivariate analyses were conducted to examine association between pre-index RI status and post-index total diabetes-related health care costs. RESULTS: Of 82 263 patients with T2DM with post-index SCr laboratory values, 34.4% had RI as evidenced by laboratory data, while 11.9% had RI using claims-based criteria. The prevalence as determined from laboratory data was roughly 3 times higher than the prevalence determined from claims data, probably due to under-recognition and under-diagnosis by providers. Compared with patients without pre-index RI, patients with RI were more likely to incur ≥ 1 diabetes-related ambulatory visit (88.8% vs 85.2%; P < 0.001), emergency room visit (7.2% vs 4.5%; P < 0.001), and inpatient stay (13.8% vs 6.6%; P < 0.001) during the 12-month post-index evaluation period. Patients with pre-index RI incurred 41.8% higher post-index total diabetes-related health care costs compared with no RI (odds ratio, 1.42 [CI, 1.29-1.56]; P < 0.001). Compared with no RI, insulin-related health care costs were independently associated with increases of 37.4% (mild RI), 166.8% (moderate RI), 408.3% (severe RI), and 343.8% (end-stage RI). CONCLUSION: Renal impairment in T2DM is associated with high health care utilization and costs.

Adherence and persistence among multiple sclerosis patients after one immunomodulatory therapy failure: retrospective claims analysis.

INTRODUCTION: There are no published data on patient adherence to, and persistence with, disease-modifying therapies (DMT) for multiple sclerosis (MS) after one immunomodulatory failure. The present study compares secondline DMT adherence and persistence among patients with MS. METHODS: Patients with MS initiating a second-line treatment with natalizumab, intramuscular interferon beta-1a (i.m.-IFNß-1a), subcutaneous (s.c.) IFNß-1a, interferon beta-1b (IFNß-1b), and glatiramer acetate (GA) from January 1, 2006 to October 4, 2008 were identified from a retrospective claims database associated with a large US health plan. Adherence was measured with medication possession ratio (MPR); adherence indicated MPR ≥ 0.80. Persistence was measured as time until a minimum 60-day gap in second-line therapy. Adherence and persistence were modeled with logistic and Cox proportional hazard regressions, respectively. RESULTS: The study population comprised 1381 patients. Multivariate analysis showed that the odds of adherence were significantly higher in the natalizumab cohort compared with all other second-line cohorts. The natalizumab cohort was more likely to be persistent compared with the i.m.-IFNß-1a and IFNß-1b cohorts. CONCLUSION: The natalizumab cohort was more adherent compared with the other second-line DMT cohorts, likely due in large part to active physician involvement and monitoring. Adherence to DMT, even after first-line failure, is critical to achieving optimal therapeutic benefit.

Comparison of adherence and persistence among multiple sclerosis patients treated with disease-modifying therapies: a retrospective administrative claims analysis.

PURPOSE: To compare adherence and persistence among patients with multiple sclerosis (MS) initiated on disease-modifying therapy (DMTs), including intramuscular (IM) interferon beta-1a (IFNß-1a), subcutaneous (SC) IFNß-1a, IFNß-1b, or glatiramer acetate (GA). METHODS: MS patients initiated on IM-IFNß-1a, SC-IFNß-1a, IFNß-1b, or GA between January 1, 2000 and January 2, 2008 were identified from a retrospective claims database study associated with a large US health plan. The date of DMT initiation was the index date; patients were observed for 6 months before and 12-36 months after the index date. Adherence to the index DMT was measured with a medication possession ratio (MPR), the proportion of days patients possessed their index DMTs; MPR ≥ 0.80 was considered adherent. Persistence was time in days from index date until the earlier of a minimum 60-day gap in DMT therapy or the last DMT claim during follow-up. Adherence and persistence were modeled with logistic and Cox proportional hazard regressions, respectively. RESULTS: The study population comprised 6,680 patients in the DMT cohorts: IM-IFNß-1a (N = 2,305, 34.5%); IFNß-1b (N = 894, 13.4%); GA (N = 2,270, 34.0%); and SC-IFNß-1a (N = 1,211, 18.1%). The IM-IFNß-1a cohort had significantly higher regression-adjusted odds of adherence relative to the other cohorts: 52.4% higher odds versus the IFNß-1b cohort (OR = 0.656, CI = 0.561-0.768); 33.5% higher odds versus the GA cohort (OR = 0.749, CI = 0.665-0.844); and 20.6% higher odds versus the SC-IFNß-1a cohort (OR = 0.829, CI = 0.719-0.957). There were no consistent differences in persistence between the cohorts. CONCLUSION: IM-IFNß-1a patients had significantly higher odds of adherence compared with other DMT cohorts, possibly attributable to IM-IFNß-1a's less frequent dosing schedule. The benefits of adherence may include better quality of life, lower risk of relapse, and fewer hospitalizations and emergency visits, making adherence a critical component of MS management.