• Airway symptoms and atopy in young children prescribed asthma medications: A large‐scale cohort study 

      Mikalsen, Ingvild Bruun; Dalen, Ingvild; Karlstad, Øystein; Eide, Geir Egil; Magnus, Maria Christine; Nystad, Wenche; Øymar, Knut (Peer reviewed; Journal article, 2019)
      Diagnosing asthma and deciding treatment are difficult in young children. An inappropriate and too high prescription rate of inhaled corticosteroids (ICS) is suggested, but how airway symptoms are associated with prescriptions ...
    • Antipsychotic drug use in pregnancy: A multinational study from ten countries 

      Reutfors, Johan; Cesta, Carolyn; Cohen, Jacqueline Mallory; Bateman, Brian T; Brauer, Ruth; Einarsdottir, Kristjana; Engeland, Anders; Furu, Kari; Gissler, Mika; Havard, Alys; Hernandez-Diaz, Sonia; Huybrechts, Krista F.; Karlstad, Øystein; Leinonen, Maarit; Li, Jiong; Man, Kenneth K. C.; Pazzagli, Laura; Schaffer, Andrea; Schink, Tania; Wang, Zixuan; Yu, Yongfu; Zoega, Helga; Bröms, Gabriella (Journal article; Peer reviewed, 2020)
      Aim To compare the prevalence and trends of antipsychotic drug use during pregnancy between countries across four continents. Methods Individually linked health data in Denmark (2000−2012), Finland (2005–2014), Iceland ...
    • Antipsychotic use in pregnancy and risk of attention/ deficit-hyperactivity disorder and autism spectrum disorder: a Nordic cohort study 

      Halfdanarson, Oskar; Cohen, Jacqueline Mallory; Karlstad, Øystein; Cesta, Carolyn E.; Bjørk, Marte-Helene; Håberg, Siri Eldevik; Einarsdottir, Kristjana; Furu, Kari; Gissler, Mika; Hjellvik, Vidar; Kieler, Helle; Leinonen, Maarit; Nørgaard, Mette; Essen, Buket Öztürk; Ulrichsen, Sinna Pilgaard; Reutfors, Johan; Zoega, Helga (Journal article; Peer reviewed, 2021)
      Background Antipsychotics are increasingly used among women of childbearing age and during pregnancy. Objective To determine whether children exposed to antipsychotics in utero are at increased risk of attention-d ...
    • Comparative Safety of Antiseizure Medication Monotherapy for Major Malformations 

      Cohen, Jacqueline Mallory; Alvestad, Silje; Cesta, Carolyn E.; Bjørk, Marte-Helene; Leinonen, Maarit; Nørgaard, Mette; Einarsdóttir, Kristjana; Engeland, Anders; Gissler, Mika; Karlstad, Øystein; Klungsøyr, Kari; Odsbu, Ingvild; Reutfors, Johan; Selmer, Randi Marie; Tomson, Torbjörn; Ulrichsen, Sinna Pilgaard; Zoega, Helga; Furu, Kari (Journal article; Peer reviewed, 2022)
      Objective: This study was undertaken to examine the comparative safety of antiseizure medication (ASM) monotherapy in pregnancy with respect to risk of major congenital malformations (MCMs), overall and by MCM subtype. ...
    • Contribution of an extensive medication-based comorbidity index (Rx-Risk) in explaining the excess mortality after hip fracture in older Norwegians: a NOREPOS cohort study 

      Holvik, Kristin; Hjellvik, Vidar; Karlstad, Øystein; Gunnes, Nina; Hoff, Mari; Tell, Grethe Seppola; Meyer, Haakon Eduard (Journal article; Peer reviewed, 2022)
      Objectives Patients with hip fracture are typically characterised by extensive comorbidities and excess mortality. Methods that account for a wide range of comorbidities are needed when attempting to identify causal ...
    • The Norwegian Society for Pharmacoepidemiology 

      Lupattelli, Angela; Karlstad, Øystein; Engeland, Anders; Småbrekke, Lars; Olsen, Kristine; Øvrebust, Aina; Waaseth, Marit (Journal article, 2021)
    • Short-term safety of COVID-19 mRNA vaccines with respect to all-cause mortality in the older population in Norway 

      Lopez-Doriga Ruiz, Paz; Gunnes, Nina; Gran, Jon Michael; Karlstad, Øystein; Selmer, Randi Marie; Dahl, Jesper; Bøås, Håkon; White, Richard Aubrey; Hofman, Aurora Christine; Paulsen, Trine Hessevik; Watle, Sara Sofie Viksmoen; Ranhoff, Anette Hylen; Bukholm, Geir; Gulseth, Hanne Løvdal; Tapia, German (Journal article; Peer reviewed, 2022)
      Background There have been concerns about COVID-19 vaccination safety among frail older individuals. We investigated the relationship between COVID-19 mRNA vaccination and mortality among individuals aged ≥ 70 years and ...