Introduction:
Lower extremity peripheral arterial disease (PAD) affects between 12% and 20% of Americans over the age of 65. PAD compromises quality of life, contributes a high burden of disability and its related health care costs exceed $4 billion/year, yet this preventable CVD outcome remains understudied.
Aims:
Assess the incidence of hospitalized PAD, and of the most severe form of PAD, critical limb ischemia (CLI), in middle-aged men and women, and evaluate their risk factors in a bi-ethnic, population-based cohort. We hypothesized that incidence of hospitalized PAD and CLI are higher in African Americans, and that modifiable atherosclerosis risk factors in middle age predict these sequelae of PAD.
Methods:
We analyzed data from 13,865 participants from the Atherosclerosis Risk in Communities Study aged 45–64 without PAD at baseline (1987–89). Incident PAD and CLI events were identified using ICD-9 codes from active surveillance of all hospitalizations among cohort participants from 1987 through 2008. All estimates are incidence rates per 10,000 person-years; nominal statistical significance was achieved for all baseline characteristic comparisons reported.
Results:
There were 707 incident hospitalized PAD during a median of 18 years of follow-up (249,570 person-years). The overall age-adjusted incidence of PAD and limb-threatening CLI were 26.0 and 9.6 per 10,000 person-years, respectively. Incidence of hospitalized PAD was higher in African Americans than whites (34.7 vs. 23.2) and in men compared to women (32.4 vs. 26.7). Baseline characteristics associated with age-adjusted incident PAD (per 10,000 person-years) compared to their referent groups were diabetes (91.2 vs. 19.0), history of smoking (33.6 vs. 16.2), hypertension (42.6 vs. 18.6), coronary heart disease (81.4 vs. 24.1), and obesity (41.5 vs. 20.2). Incidence of CLI also was higher among African Americans (21.0 vs. 5.9) and in men (10.5 vs. 8.9 per 10,000 person-years). Baseline characteristics associated with incident CLI were similar to those for PAD.
Conclusions:
The absolute risk of hospitalized lower extremity PAD in this community-based cohort is of a magnitude similar to that of heart failure and of stroke. As modifiable factors are strongly predictive of the long-term risk of hospitalized PAD and CLI, particularly among African Americans, our results highlight the need for effective risk factor prevention and control.
Variability and Outcomes of Medical and Lifestyle Management of Peripheral Arterial Disease at the Time of Lower Extremity Bypass
