Funding for this research was provided by:
Sahlgrenska Universitetssjukhuset (ALF 70150, ALF 74140)
Göteborgs Läkaresällskap (GLS 717831)
Received: 22 March 2019
Accepted: 16 July 2019
First Online: 23 July 2019
Ethics approval and consent to participate
: The study was approved by the Regional Ethics Committee in Gothenburg (Reg nr 735–18) and performed in accordance with the ethical standards of the 1964 declaration of Helsinki and its later amendments. In accordance with the Regional Ethics Committee consent from the patients was not needed due to the retrospective nature of the study. All patients had previously given informed consent for storage of serum samples in a biobank according to a prior approval by the Regional Ethics Committee (Ö 588–01). The stored serum samples were used according to the national regulations of the National Biobank Council.
: Not applicable.
: The authors declare that they have no competing interests.