Abstract
Elevated D-dimer levels are reportedly associated with higher risk of total mortality in patients with different diseases. We investigated whether a similar association could be found in a large, apparently healthy population. A large sample of individuals (N=17,359, 47% men, age ≥ 35 years) free of clinically recognized cardiovascular and cancer disease, for whom baseline D-dimer level was available, were studied within the MOLI-SANI cohort, randomly recruited from the general adult population of Southern Italy. The cohort was followed for a median of 4.2 years (73,807 person-years). D-dimer was measured in fresh citrated plasma by an automated latex-enhanced immunoassay. Hazard ratios were calculated using three Cox-proportional hazard models. Two hundred and eighty deaths were recorded. When modeled as a continuous variable, D-dimer level at baseline showed a non-linear association with mortality, whose incidence increased only in the upper quartile of the distribution (D-dimer ≥ 221 ng/mL). Thus, the group of individuals with D-dimer <221 ng/mL (75% of the population) acted as the reference group, while the remaining individuals were subdivided in tertiles and compared with the former group. Multivariable hazard ratios for mortality were 1.06, 1.45 and 1.97, respectively (P for trend <0.0001) across the three categories of increasing D-dimer concentration. The association was slightly attenuated, but still highly significant (P for trend 0.0002), after further adjustment for white blood cell count and C-reactive protein. In conclusion, Elevated D-dimer levels were independently associated with increased risk of death from any cause in an apparently healthy adult population.