Patients with severe
renal insufficiency (sRI) have been suggested to be at an increased risk of
bleeding with low-molecular-weight heparins (
LMWH). We aimed at assessing the benefits and risks of
certoparin in comparison to
unfractionated heparin (UFH) in these patients. In this subgroup analysis of the CERTIFY trial, acutely ill, non-surgical patients ≥70 years received
certoparin 3,000U aXa o.d. or UFH 5,000 IU t.i.d. One hundred eighty-nine patients had a glomerular filtration rate (GFR) ≤30 ml/min/1.73 m2, 3,050 patients served as controls. Patients with sRI had a mean age of 85.9 ± 6.6 years (controls 78.4 ± 6.0) and were treated for a mean of 9.3 ± 3.7 days (9.9 ± 4.3). Thromboembolic event rates were comparable (4.55 vs. 4.21%; OR1.08; 95%CI 0.5-2.37) but
bleeding was increased in sRI (9.52 vs. 3.54%; OR2.87; 95%CI 1.70-4.83). The incidence of the combined end-point of proximal DVT, symptomatic non-fatal PE and VTE related death was 6.49% with
certoparin and 2.60% with UFH (OR2.60; 95%CI 0.49-13.85). There was a decrease in total
bleeding with
certoparin (OR0.33; 95%CI 0.11-0.97), which was non-significant in patients with GFR >30 ml/min/1.73 m2. In two multivariable regression models
certoparin and immobilisation <10 days were associated with less
bleeding while a GFR ≤30 ml/min/1.73 m2 was associated with increased
bleeding. A total of 11.3% of
certoparin- and 18.5% of UFH-treated patients experienced serious adverse events (14.8 in patients with a GFR ≤30 vs. 5.6% vs. >30 ml/min/1.73 m2). In conclusion,
certoparin 3,000U anti Xa o.d. was as efficacious as 5,000 IU UFH t.i.d. in patients with sRI but had a reduced risk of
bleeding.