The role of comorbidity burden for patients with symptomatic peripheral arterial disease (PAD). A quantitative approach.

AIM

Comorbidity will play an increasingly important role in PAD management. Therefore, we aimed 1) to address the comorbidity load of PAD patients quantitatively and comprehensively, 2) to delineate the effects of composite comorbidity measures on general and disease-specific aspects of quality of life and on crude markers of resource allocation.

METHODS

One hundred and one consecutive symptomatic PAD patients (80 males, 21 females; mean age: 66.4 +/- 9.1 years) were assessed by means of a cumulative illness rating scale (CIRS: 14 items; individual item rating from 1 for no through 5 for life-threatening impairment). Outcome measures were the illness severity score (CIRS-IS, mean of all single item scores) and the comorbidity index (CIRS-CI, number of single items with a score of 3, 4 or 5). These comorbidity indices of the PAD patients were compared with those of both 89 elderly community-dwelling volunteers (44 males, 45 females, mean age 77.4 +/- 5.3 years) we had investigated previously and 439 geriatric residents (121 males, 318 females; mean age 84.1 +/- 5.7 years) reported by Parmelee et al. in 1995. Furthermore, the PAD patients estimated their quality of life (LQ), subjective health status (HS), leg pains during either rest or walking on rating scales (ranging from 0 for the best to 10 for the worst result).

RESULTS

PAD patients showed very high comorbidity indices and illness severity scores (CIRS-CI: 3.98 +/- 1.60; CIRS-IS: 1.86 +/- 0.29). These proved to be greater than those of both fit community-dwelling elderly subjects (CIRS-CI: 1.82 +/- 1.46; CIRS-IS: 1.62 +/- 0.22) and older institution residents (CIRS-CI: 2.17 +/- 1.85; CIRS-IS: 1.64 +/- 0.34). Furthermore, both CIRS-CI and CIRS-IS were significantly greater in patients with more advanced PAD stage. These indices of comorbidity load were also associated with quality-of-life impairments (r=0.253, p=0.0186), degree of ischemic rest pain (r=0.251, p=0.0196), extent of medication usage (r=0.511, p<0.0001) as well as duration of in-hospital stay (r=0.271, p=0.0084).

CONCLUSION

PAD patients have a markedly increased comorbidity burden. This was greater in the more advanced PAD stages and significantly associated with quality-of-life reductions and the extent of resource allocation. A quantitative approach to the comorbidity load in PAD patients appears to be possible by means of such a scale and useful for both clinical and socioeconomic purposes.