2006 HSR&D National Meeting Abstract
1061 — Risk for Death Following Limb Surgery in Veterans with Peripheral Arterial Disease
Collins TC (Houston Center for Quality of Care and Utilization Studies)
Ku-Goto M (Houston Center for Quality of Care and Utilization Studies)
Petersen NJ (Houston Center for Quality of Care and Utilization Studies)
We sought to determine the risk factors associated with death following a surgical limb event for patients with peripheral arterial disease (PAD).
This retrospective cohort study of patients with PAD (defined by an ankle-brachial index [ABI] < 0.9 between 1995 and 1998 at a large VA Medical Center) included chart, pharmacy, and VA administrative data review for risk-factor control from three years before the ABI date until the first event or the end of the study (December 31, 2001). Based on the percentage of visits for which the risk factor met specified criteria, we defined levels of control as low or high (e.g., for diabetes mellitus, a low level of control was defined as glucose control for 0-74 percent of visits with a high level of control defined as control for 75 percent or more of visits). We determined the risk of development of adverse limb events using a t- or chi-square test. We determined the association between risk factor control and mortality by applying Cox proportional hazards models.
Of 796 patients (mean age, 65± 9.9 years), 230 (28.9 percent) experienced an adverse limb event [136, lower-extremity bypass; 94, lower-extremity amputation]), and 354 (44.5 percent) died;107 (13.4%) died following a limb event. Factors significantly associated with death following a limb event included African American race (HR 2.4; 95% CL 1.5, 3.6), ABI <0.41 (HR 10.9; 95% CL 4.5, 26.6), ABI 0.41 – 0.69 (HR 4.2; 95% CL 1.8, 9.7), and a creatinine of 2.1 or higher (HR 3.0; 95% CL 1.7, 5.4). Process of care factors that were associated with an increased risk for mortality included a low level of medication use to control hyperlipidemia (HR 1.9; 95% CL 1.1, 3.4) and a low level of glucose control (HR 2.6; 95% CL 1.5, 4.5).
In addition to African American race, PAD severity, and renal insufficiency, low levels of lipid medication exposure and glucose control were associated with increased risk for death following a limb event. These data suggest that low-density lipoprotein and glucose control are critical for survival in veterans following surgical intervention for their PAD.
Process of care factors may have a positive impact on survival following limb events in patients with PAD.