Chronic leg symptoms after deep venous thrombosis (DVT) (the postthrombotic syndrome) are common but difficult to predict.
By using a standardized scale, Kahn and coworkers evaluated leg symptoms in 387 patients for 2 years after DVT. Mild, moderate,
and severe postthrombotic syndrome occurred in 30%, 10%, and 3% of patients, respectively, at all study intervals, but severity
fluctuated over time in many patients. Age, previous DVT, and severity at 1 month were the best predictors of long-term severity.