Factor VII Deficiency Is More Prevalent than Previously Reported

Authors: Löwing Svensson, L; Aardal, E; Holmström, M

Affiliations: Departments of Clinical Chemistry and Biomedical and Clinical Sciences, Linköping University, Linköping, Sweden. Departments of Health, Medicine and Caring Sciences, and Acute Internal and Geriatric Medicine, Region Östergötland, Linköping University, Linköping, Sweden.

Publication: Research and practice in thrombosis and haemostasis; 2026; 10. 103284

ABSTRACT: BACKGROUND The prevalence of factor (F)VII deficiency is estimated at approximately 1 of 500,000 individuals. However, low FVII activity (FVII:C) is frequently observed in a population of <500,000 in the region of Östergötland, Sweden. OBJECTIVES To estimate the prevalence and bleeding tendency of adult FVII-deficient patients in Östergötland, Sweden. METHODS In this retrospective cross-sectional study, the laboratory information system was used to identify adult patients with at least one FVII:C result ≤ 0.50 kilo International Units per Liter (kIU/L) between January 1, 2017, and December 31, 2022. The most likely cause was established, and in patients with a FVII deficiency, as defined by the Nordic Hemophilia Council (FVII:C < 0.35 kIU/L) or low FVII level (0.35-0.50 kIU/L), the bleeding tendency was evaluated. RESULTS FVII:C ≤ 0.50 kIU/L was identified in 97 patients residing in Östergötland. Of these, 21 had FVII deficiency, and 39 had low FVII level, corresponding to a prevalence of at least 1 of 17,800 and 1 of 9600 in the adult population in Östergötland, respectively. Patients with FVII deficiency differed significantly from patients with low FVII level in bleeding symptoms (P = .01). Of the FVII-deficient patients, 38% were asymptomatic, while 19% and 24% had experienced minor and major spontaneous bleedings, respectively. CONCLUSION The prevalence of FVII deficiency was estimated to be at least 1 of 17,800 adults, which is 28 times higher than the internationally claimed prevalence. Spontaneous bleeding occurred in 43% of these individuals.