Amputation trends for patients with lower extremity ulcers due to diabetes and peripheral artery disease using statewide data

Abstract

Objective This study reports all-payer amputation rates using state-based administrative claims data for high-risk patients with lower extremity (LE) ulcers and concomitant peripheral artery disease (PAD), diabetes mellitus (DM), or combination PAD/DM. In addition, we characterize patient factors that affect amputation-free survival. We also attempted to create a measure of a patient’s ability to manage chronic diseases or to access appropriate outpatient care for ulcer management by accounting for hospital and emergency department (ED) visits in the preceding 60 days to determine how this also affects amputation-free survival. Methods Patients admitted to nonfederal hospitals, seen in an ED, or treated in an eligible ambulatory surgery center within California from 2005 through 2013 with an International Classification of Diseases, Ninth Revision, Clinical Modification diagnosis code for a disease-specific LE ulcer were identified in the California Office of Statewide Health Planning and Development database. All subsequent hospital, ED, and ambulatory surgery center visits and procedures are captured to identify whether a patient underwent major amputation. Yearly amputation rates were determined to analyze trends. Amputation-free survival for the PAD, DM, and PAD/DM groups was determined. Cox modeling was used to evaluate the effect of patient characteristics. Results There were 219,547 patients identified with an incident LE ulcer throughout the state. Of these, 131,731 were DM associated, 36,193 were PAD associated, and 51,623 were associated with both PAD and DM. From 2005 to 2013, the number of patients with LE ulcers who required inpatient admission, presented to the ED, or had outpatient procedures was stable. However, there was a statistically significant increase in overall disease-associated amputation rates from 5.1 in 2005 to 13.5 in 2013 (P < .001). Patients with PAD/DM had the greatest increase in amputation rates from 10 per 100 patients with LE ulcers in 2005 to 28 per 100 patients in 2013 (P < .001). Despite that patients with PAD/DM were 8 years younger than patients with PAD only, they had similar amputation-free survival. Within all age groups, men had worse amputation-free survival than women did. Race did not predict amputation-free survival, but having multiple prior ED or hospital admissions was a significant predictor of worse amputation-free survival. Conclusions Potentially preventable amputations associated with high-risk diseases are increasing among patients who require inpatient hospital admission, present to the ED, or require outpatient interventional treatment. This trend is most notable among patients with a combination of PAD and DM. Patients with repeated hospitalizations before admission for the LE ulcer had the highest risk of amputation.

Impact of diabetes on outcome in critical limb ischemia with tissue loss: a large-scaled routine data analysis

“…CLI patients with diabetes are at average 3 years younger compared to non-diabetic patients at the same Rutherford grade. This trend conforms with other studies [11, 21], and likely reflects the progressing effect of diabetes on the arterial calcification and clinical severity of PAD. Further, diabetic CLI patients are shown higher ratio of obesity, dyslipidemia, or hypertension as common co-morbidities (“metabolic syndrome”), as well as higher ratio of chronic kidney disease or coronary artery disease as common sequelae of diabetes [22].…”

“…It may be concluded, that end-stage PAD patients with tissue loss have such poor prognosis in terms of survival (50–60% at 4 years), that concomitant diabetes itself would not relevantly further increase mortality rates. This finding is paralleled by Humphries et al [21] that did not show any further deteriorating effect of diabetes on in-hospital mortality of PAD patients with lower extremity ulcers on statewide data for California, USA. In face of the recent nationwide study by Agarwal et al [34] the more frequently used endovascular treatment strategy in the diabetic sub-group might add to the improved survival.…”

“…Further, diabetic CLI patients are shown higher ratio of obesity, dyslipidemia, or hypertension as common co-morbidities (“metabolic syndrome”), as well as higher ratio of chronic kidney disease or coronary artery disease as common sequelae of diabetes [22]. The lower smoking rate in diabetic CLI patients [21] might partially result of a selection bias, since smoking dramatically increases the risk for PAD [adjusted Odds Ratio 10.4 (3.8–28.3) compared to Odds Ratio 2.3 (1.4–3.8) for diabetes; p < 0.01; [23]), yet cannot be entirely explained; on the other hand, diabetic patients might benefit from frequent ambulatory consultations including educative and preventive measures eventually resulting in decreased rate of tobacco use. We observed a higher ratio of male patients in diabetic compared to non-diabetic CLI patients with tissue loss.…”

Race and Socioeconomic Status Independently Affect Risk of Major Amputation in Peripheral Artery Disease

“…Contemporary studies have shown a decline in amputation rates for Medicare beneficiaries with PAD in general and across racial subgroups, although disparities still exist 3, 38. Multidisciplinary preventative measures such as diabetic control and wound care, along with patient and community engagement, seem to decrease racial disparity in limb loss among diabetic patients and may hold promise in PAD care 12, 38, 39. Increased awareness and education of providers in reducing implicit bias in the treatment of PAD is also needed 40.…”

“…Some authors have argued that race could be a marker for socioeconomic status (SES) and thus for healthcare access, as the reason for racial disparity in vascular outcomes 11, 12, 13. Lack of access to care and regional clustering have been shown to affect black patients disproportionately 3, 7.…”