Abstract 1038: Population-based Study of Event-rate, Incidence, and Outcome for Peripheral Vascular Events: The Oxford Vascular Study
Background: There are no reliable, population-based data on the incidence and outcome of acute peripheral vascular events, such as critical limb ischaemia (CLI), acute thromboembolic limb ischaemia (ALI) or acute visceral ischaemia (AVI). Outcome data are limited to clinical trials and hospital cohort studies. Reliable population-based data are required to inform health service planning, to enable risk prediction for peripheral vascular disease and to direct future research.
Methods: As part of the ongoing Oxford Vascular Study, we prospectively determined incidence rates and outcomes for all acute peripheral vascular events, irrespective of age in a population of 91,163 in Oxfordshire, UK, during 2002–2007. We report these rates by age, sex, and vascular territory.
Results: Of 214 acute peripheral vascular events in 170 patients ascertained, 132 (61.7%) were CLI (median (IQR) age 75(66 – 81), 61.4% male) and 82 (38.3%) were thromboembolic (median (IQR) age 78 (66 – 89), 54.9% male). Event-rates and incidence increased steeply with age. Overall incidences were 0.21 (0.17– 0.25), 0.14 (0.11– 0.18) and 0.03 (0.02– 0.06) per 1000 per year respectively for CLI, ALI and AVI. Survival at 1 month, 3 months, 1 year and 5 years was 83%, 71%, 59% and 52% for ALI, 95%, 84%, 65% and 51% for CLI, and 35%, 29%, 29% and 29% for AVI. For ALI, the probabilities of survival at 30 days, 90 days, 1 year and 5 years were 93%, 86%, 69% and 69% for viable, 82%, 68%, 57% and 42% for threatened and 33%, 17%, 17% and 17% for irreversible limb ischaemia. For CLI, disease severity also had an adverse effect on outcome. The probabilities of survival at 30 days, 90 days, 1 year and 5 years were 95%, 92%, 90% and 72% for presentations with rest pain only and 94%, 81%, 55% and 42% for presentations with tissue loss.
Conclusions: Acute peripheral arterial events represent a significant disease burden, particularly over the age of 75 years, and have very poor outcome. The severity of disease (as measured by consensus scoring systems) in critical ischaemia and acute ischaemia predicts mortality and amputation. Primary and secondary prevention strategies for peripheral vascular disease must be improved.