OBJECTIVES: To investigate whether long-term growth hormone (GH) replacement therapy in GH deficient (GHD) adults results in improvements in Quality of Life (QoL), patient-reported outcomes and health care utilization (HCU) in the Netherlands. METHODS: The analysis was based on 74 patients (35 men, 39 women) and all patients were included in KIMS (Pharmacia International Metabolic Survey) - the largest pharmacoepidemiological survey of GHD adults on GH therapy. Data were available for all patients for the first year of treatment, and 2-year follow-up data were available for 38 patients. QoL was assessed using the Nottingham Health Profile (NHP) and disease-specific AGHDA questionnaire. Patient reported outcomes and data on HCU were obtained with the Patient Life Situation Form (PLSF). Statistical analyses were performed with repeated measurements technique. RESULTS: Both QoL questionnaires showed a significant improvement after 1 and 2 years of GH therapy (from 20.1±2.6 to 10.1±2.5 for NHP, from 9.3±0.82 to 7.2±1.11 for AGHDA). Data collected with the PLSF showed a subjective improvement in personal well-being for 65% of the patients after 1 and 2 years of GH treatment. Visits to the doctor in the previous year (from 9.1±1.4 to 3.4±1), days in hospital (from 7.9±2.6 to 1.6±1.5) and days of sick leave (from 26.4±9.8 to 2.2±1.1) significantly decreased during GH therapy. Leisure-time physical activity significantly improved during therapy, whereas satisfaction with physical activity improved only in females. Another gender difference relates to the need for assistance with daily activities, which remained low and constant in males, but seemed to worsen in females. CONCLUSION: Data obtained so far confirm that GH replacement therapy results in a significant long-term improvement of both QoL and general well being and reduction of HCU in the Netherlands. Moreover, after two years of GH therapy both QoL and HCU levels become comparable to the general Dutch population.