UC San Diego

Background

Several hemostatic factors and inflammatory markers are associated with the risk of incident venous thromboembolism (VTE), however, most existing data are from case-control studies in Caucasian populations.

Objectives

We aimed to prospectively confirm previous findings and explore less studied biomarkers in relation to VTE risk in a multi-racial/multi-ethnic cohort.

Methods

Circulating levels of factor VIII, fibrinogen, D-dimer, plasmin-antiplasmin complex (PAP), C-reactive protein (CRP), and interleukin-6 (IL-6) were measured at baseline (2000-2002) in 6706 participants of the Multi-Ethnic Study of Atherosclerosis. Incident VTE was identified using hospitalization discharge codes from baseline to December 31, 2015. Hazard ratios (HRs) of VTE were estimated in Cox regression models.

Results

There were 227 events during a median of 14 years of follow-up. Compared with participants in the lowest quartile, the HRs for those above the 95th percentile and p for trend across categories were 3.50 (95% confidence interval [CI] 1.98-6.19; p < .001) for D-dimer, 1.49 (95% CI 0.84-2.63; p = .02) for factor VIII, 1.32 (95% CI 0.76-2.28; p = .99) for fibrinogen, 1.92 (95% CI 1.08-3.42; p = .15) for PAP, 1.68 (95% CI 0.81-3.48; p = .08) for CRP, and 2.55 (95% CI 1.15-5.66; p = .07) for IL-6, after adjustment for demographics and body mass index. For CRP and IL-6, follow-up was restricted to 10 years because of violations of the proportional hazards assumption. No significant interactions by age/ethnicity were observed.

Conclusions

We demonstrated a fairly novel association between PAP and risk of incident VTE, and contributed further prospective confirmation regarding the associations of D-dimer, factor VIII, and IL-6 with VTE.