Plasma fibrinogen in ulcerative colitis: the effect of disease activity and nicotine therapy in a randomised controlled trial.

BACKGROUND

Smoking increases plasma fibrinogen and cardiovascular risk whereas transdermal nicotine may not. Fibrinogen is an acute phase protein and may reflect disease activity in ulcerative colitis.

AIMS: To examine the effect of topical nicotine on plasma fibrinogen and any relationship between fibrinogen and ulcerative colitis disease activity.

PATIENTS: Forty-eight non-smokers with moderately active ulcerative colitis.

METHODS

Patients were randomised to 6 mg nicotine enema or placebo for 6 weeks, followed by open nicotine therapy for 4 weeks. Plasma fibrinogen was measured at baseline and after 6 and 10 weeks; at each assessment sigmoidoscopy with a rectal biopsy was performed. RESULTS.: At 6 weeks median plasma fibrinogen was 3.30 g/l on nicotine compared to 3.05 g/l on placebo, P = 0.90 when adjusted for baseline values. There was a correlation between fibrinogen and the UC disease activity index (UCDAI) at weeks 0 and 10, P = 0.036 and 0.033, respectively, and between fibrinogen and sigmoidoscopic grade at each assessment, P = 0.014, 0.021 and 0.034. Changes in fibrinogen did not correlate with changes in disease severity.

CONCLUSIONS

There was no significant effect of nicotine enemas, in either direction, on plasma fibrinogen-this was raised in moderately active UC and correlated with the sigmoidoscopic grade of colitis and the UCDAI; however, fibrinogen was not sufficiently sensitive to be of practical clinical value.