Factor VII deficiency is more prevalent than previously reported

TL;DR

Factor VII deficiency is more common in a region of Sweden than previously thought, with a higher prevalence and significant bleeding risks in affected individuals.

Contribution

The study reports a 28-fold higher prevalence of FVII deficiency in Östergötland, Sweden, compared to international estimates.

Findings

FVII deficiency was found in 1 of 17,800 adults in Östergötland, much higher than the global estimate of 1 in 500,000.

43% of FVII-deficient patients experienced spontaneous bleeding, indicating a significant clinical impact.

Patients with FVII deficiency showed significantly more bleeding symptoms than those with low FVII levels.

Abstract

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.

To estimate the prevalence and bleeding tendency of adult FVII-deficient patients in Östergötland, Sweden.

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.

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.

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.

•FVII deficiency is a rare bleeding disorder with a reported prevalence of 1 in 500,000 individuals.•This study used laboratory and patient records to identify cases and estimate bleeding tendency.•FVII deficiency was found in 1 in 17,800 adults, which is higher than expected.•Forty-three percent of FVII-deficient patients had experienced spontaneous bleeding episodes.

FVII deficiency is a rare bleeding disorder with a reported prevalence of 1 in 500,000 individuals.

This study used laboratory and patient records to identify cases and estimate bleeding tendency.

FVII deficiency was found in 1 in 17,800 adults, which is higher than expected.

Forty-three percent of FVII-deficient patients had experienced spontaneous bleeding episodes.

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