Pharmacological treatment of obesity in adults in Norway 2004-2022.

AIMS: To describe trends in the use of anti-obesity drugs in Norway during the period 2004-2022. MATERIALS AND METHODS: We assessed the annual utilization of any available drug indicated for obesity recorded in the nationwide Norwegian Prescribed Drug Register for adults (age 18-79 years) from 1 January 2004 to 31 December 2022. Prevalence was stratified by sex and age group (18-29 years and 10-year age groups thereafter). Additional analyses were performed in individuals initiating treatment with an anti-obesity drug and on the cost of the anti-obesity drugs since 2017. RESULTS: The prevalence of anti-obesity drug use decreased from 2009, when sibutramine and rimonabant were withdrawn from the market, and increased again after the approval of bupropion-naltrexone in 2017 and liraglutide in 2018. The use of the peripheral-acting anti-obesity drug orlistat decreased from 2004. In 2022, 1.04% of the adult Norwegian population (72.8% women) filled at least one prescription of bupropion-naltrexone, 0.91% used liraglutide (Saxenda; 74.2% women), and semaglutide without reimbursement was used by 0.68% (76.7% women). The prevalence increased with age, peaking in the age group 50 to 59 years, and decreased in older age groups. From 2017 to 2022, 2.8% of the adult residents initiated treatment with an anti-obesity drug. The total sale of those drugs increased from 1.1 million euros in 2017 to 91.8 million euros in 2022. CONCLUSIONS: The use of anti-obesity drugs in Norway has increased substantially in recent years, especially among women aged 40 to 59 years. Changes in availability and reimbursement have influenced the use of these drugs in recent years.