Post-thrombotic syndrome 3 years after deep venous thrombosis in the Thrombosis and Pulmonary Embolism in Out-Patients (TULIPA) PLUS Registry.

BACKGROUND

Reported post-thrombotic syndrome (PTS) rates may be confounded by including patients with a history of deep venous thrombosis (DVT) before the index event, varicose veins, or chronic venous insufficiency independent of PTS. We were interested in assessing PTS incidence rates of patients without these pre-existing disease conditions.

METHODS

A prospective registry with a 3-year follow-up after an initial DVT was assessed. Available for analysis were 135 ambulatory patients without a history of DVT (before the index DVT), signs of varicose veins, or chronic venous insufficiency affecting the ipsilateral or contralateral leg, and Villalta score.

RESULTS

PTS was detected in 24.5% of patients, with 17.0% having mild (Villalta score, 5-9), 6.0% moderate (score, 10-14), and 1.5% severe PTS (score ≥15) after a first DVT. Of these, 52.6% had proximal and 47.4% distal DVT; 63.7% were provoked and 35.6% unprovoked (one patient missing). Patients with proximal DVT (32.4%) significantly more often developed any PTS compared with patients with distal DVT (15.6%; P = .024); however, groups were similar with regard to severity of PTS by the four-level Villalta score (P = .109). In univariate analysis, PTS was more frequent (odds ratio, 95% confidence interval) with higher age (1.06 per year; 1.02-1.09), a body mass index of 25 to 30 kg/m(2) (2.38; 0.71-7.97) and ≥30 kg/m(2) (6.08; 1.75-21.14), proximal vs distal DVT (2.59; 1.12-5.98), and calf swelling ≥3 cm larger than the asymptomatic leg (3.77; 1.66-8.55). In a multivariate analysis, age (1.05; 1.01-1.09) and calf swelling ≥3 cm larger than the asymptomatic leg (2.94; 1.20-7.20) remained predictive for PTS. Compression therapy was used by 78.5% of patients at the 1-year follow-up and by 46.7% at the 3-year follow-up. Both rates were higher in patients with PTS (93.9%) vs no PTS (66.7%).

CONCLUSIONS

This prospective survey demonstrates a low rate of PTS in patients with a first DVT and no pre-existing DVT, varicose veins, or chronic venous insufficiency, and a high adherence rate to compression therapy, within the first 3 years of follow-up. Age and marked calf swelling were independent predictors of PTS.