OBJECTIVES: To evaluate lifetime clinical and economic outcomes in the Swedish setting for patients with type 1 diabetes treated with either insulin aspart (IAsp) or human soluble insulin (HSI) as mealtime insulin, based on a multinational clinical trial. METHODS: A validated diabetes model was used to project long-term cumulative incidence of complications, life expectancy (LE), quality-adjusted life expectancy (QALE) and lifetime costs for IAsp versus HSI. Markov modeling techniques were used to describe incidence and progression of complications (eye, renal and cardiovascular disease, and peripheral neuropathy), and Monte Carlo simulation accounted for uncertainty. Probabilities of complications and HbA1c-dependent adjustments were derived from landmark clinical and epidemiological studies. Cohort definition and intervention effects were taken from a 30-month multicenter, multinational, open-labeled phase III extension trial in patients with type 1 diabetes. Costs were retrieved from published sources and expressed in 2005 Swedish Kronor (SEK) from a societal perspective (human capital approach). LE, QALE and total costs were projected over a 50-year time horizon and discounted at 3% per annum. RESULTS: IAsp was associated with an increase in LE of 0.13 years (16.38±0.17 versus 16.26±0.17) and in QALE of 0.14 quality-adjusted life years (QALYs) (10.86±0.11 versus 10.72±0.11) compared to HSI. The cumulative incidence of most diabetes-related complications was estimated to be lower for IAsp versus HSI. Long-term direct costs were slightly higher with IAsp than with HSI (SEK 568,532±13,682 versus 567,920±15,127), leading to an incremental cost-effectiveness ratio of SEK 4,373 per QALY gained for IAsp versus HSI. From a societal perspective, IAsp was life and cost saving (dominant) compared to HSI, assuming that workplace productivity improved with diabetes-related complications avoided. CONCLUSIONS: Over patient lifetimes, IAsp was projected to improve LE and QALE and reduce the cumulative incidence of diabetes-related complications, with cost savings from a societal perspective in Sweden, compared to HSI.