Pdb24 direct healthcare and indirect workloss costs associated with the addition of rosiglitazone (rsg) versus sitagliptin (stg) therapy to metformin (met)

We compared healthcare resource utilization (HRU) and costs associated with add-on therapy of RSG versus STG to MET. Type II diabetes mellitus patients, ≥18 years, initiating RSG or STG (first dispensing = index date) add-on therapy with MET were identified in the PharMetrics database (1999-2008). Patients were continuously enrolled for ≥6 months pre-index (baseline) and 12 months post-index, had ≥1 dispensing for MET in the 6-month pre-index period, did not use insulin or sulfonylurea, and were treated with RSG+MET before 05/01/2007 or STG+MET for ≥6 months post-index. All-cause and diabetes-related HRU and annual costs ($2008) were reported for the 12-month follow-up period. Workloss costs were estimated by applying hourly wage from the Bureau of Labor Statistics to missed work hours (hospitalization=8 hours; outpatient/emergency room [ER] visit=4 hours). Multivariate analyses were conducted, adjusting for baseline demographics, comorbidities, and costs. Compared to STG+MET cohort (N=1,660) at baseline, RSG+MET cohort (N=3,731) was younger (55 vs. 58 years) with fewer comorbidities (Charlson Comorbidity Index [0.26 vs. 0.34]), and had lower total costs (RSG+MET: $7,875; STG+MET: $9,412; cost difference=$1,536, p=0.0043). Frequency and costs of hospitalizations and ER visits were not different at baseline. In the 12 months post-index period, all-cause HRU and corresponding annual cost difference between RSG+MET and STG+MET cohorts was enlarged (RSG+MET: $8,443; STG+MET: $10,757; cost difference=$2,314, p<0.0001). After adjusting for covariates, the cost decrease associated with RSG+MET remained statistically significant (cost difference=$1,248; cost ratio=0.87; P=0.0120). Diabetes-related adjusted incremental cost saving of RSG+MET over STG+MET was $599 (cost ratio=0.83, P=0.0160). The adjusted workloss cost was also lower for RSG+MET compared to STG+MET (cost difference=$22, cost ratio=0.93; P=0.0120). Compared to the new DPP-4 agent STG combined with MET, RSG, a thiazolidinedione, combined with MET was associated with lower all-cause and diabetes-related direct healthcare costs and indirect workloss costs.