Role of Vitamin D Levels in Venous Thrombosis

Abstract

Venous thromboembolism (VTE) is a complex condition that impacts over 900,000 people in theUnited States annually. It is estimated that about 100,000 people in the US die from deep veinthrombosis (DVT) or pulmonary embolism (PE) annually. Several biomarkers, includingVitamin D most recently, have been investigated and linked to the risk of developing VTE orrecurrent VTE. Vitamin D is known to control the expression of over 200 genes and it has shownto have anti-thrombotic effects through various mechanisms. There is emerging data regardingits role in the coagulation pathway, platelet activation, inflammatory pathways and endothelialactivation (1). There have been a few international studies linking Vitamin D deficiency toVTE(2). However; no such study has been replicated in the North American population where the prevalence of Vitamin D deficiency is 40%. The focus of this study will be to determine theprevalence of Vitamin D deficiency in patients with VTE. Based on the role of Vitamin D in thepathway for thrombogenesis and antithrombin effects, there is likely a correlation between VTEand Vitamin D levels.This is a retrospective chart review of all patients admitted to Franciscan Health- Olympia Fieldswith VTE between July 2018 and June2020. A total of 181 patients with VTE were reviewed.Data such as age, gender, race, D-dimer, and Vitamin D levels were collected. Vitamin D levels<30ng/mL was defined as deficient. In addition, further data collection, included provoked vsunprovoked VTE, presence of malignancy, and the severity of DVT and PE based on locationand extent of the VTE (severity was scored on a scale of 1-3 with 1 being mild and 3 as severe).A regression analysis was done to find a correlation between several variables and T-test wasused to determine P-value.Of the 181 patients, 110 had a vitamin D level documented at the time of their VTE and datawas specifically analyzed for this subgroup. There were 46 males and 64 females, 53.6%AA,7.3% Hispanic, 38.2% Caucasian, and 0.9% unknown. 25.5% had an unprovoked VTE eventand 74.5% had a provoked event. 39 patients had a known active malignancy and a likelycancer associated thrombosis. 85.7% of patients with unprovoked DVT had a low Vitamin Dlevel. In patients with cancer associated thrombosis there was no significant correlation withvitamin D levels. A strong correlation was noted between vitamin D levels and the severity of PE(p value=0.036).This retrospective chart review from a patient population at a community hospital indicates thatthere is some correlation between venous thromboembolism and Vitamin D levels. Specifically,it appears that patients with an unprovoked VTE have low Vitamin D levels suggesting thatvitamin D deficiency may be a risk factor for VTE development as indicated by previousinternational studies (2). In addition, it appears that there is an inverse relationship between theseverity of PE and vitamin D levels. Perhaps Vitamin D may be used as a biomarker for VTErisk assessment and management. Large scale studies are needed in the future to determinethe exact relationship between VTE and Vitamin D and further studies are needed to test therole of vitamin D supplementation and risk of recurrent VTE. DisclosuresNo relevant conflicts of interest to declare.