[Peripheral arterial disease: predictors and treatment intensity. Two-years of data from the population-based INVADE project]

Abstract

Background and purpose: Asymptomatic peripheral arterial disease (PAD) is very common in the elderly and can be detected in 15-20% of patients above 55 years. The aim of this study was to determine PAD prevalence and risk factors within the population of the overall INVADE project (INtervention project of cerebroVAscular diseases and Dementia in the District of Ebersberg [Bavaria]), a prospective non-randomized analysis.

Patients and methods: A total of 3,909 participants were included in the INVADE project. An ankle-brachial index (ABI) measurement was available in 3 891 subjects. An additional 40 patients were excluded because their ABI was >1,5. The analysis was thus based on 3,851 participants. The mean age was 70.1 years (95% confidence interval: 69,8 - 70,3). There were 2 285 (59.3%) women. The changes of the different classical vascular and risk factors as well as various laboratory parameters, including high sensitivity C-reactive protein (hs-CRP) were recorded and analysed by the paired t-test or the Fisher's exact test. Independent predictors were calculated by multiple logistic regression analysis.

Results: The prevalence of PDA was 18.6%. In 75% of the PAD patients the diagnosis had been unknown before study onset. Those with PAD were significant younger (69.6 vs. 72.2 years; p<0.0001), had significant lower hsCRP values (3,8 mg/l vs. 4.9 mg/l; p=0.002) and a lower vascular risk profile. After two years of intervention an improvement of vascular risk factors and reduction in necessary treatment, such as antihypertensives and platelet inhibitors, was documented. Independent risk factors for PAD development, in addition to the baseline ABI, were age, years of smoking (packs per day) and hsCRP.

Conclusion: The INVADE project confirms the high prevalence of PAD in an elderly population. These data underline the importance of measuring hsCRP for diagnosing and following PAD development.