Peripheral arterial disease (PAD) is a progressive atherosclerotic condition that affects >200 million people worldwide, including a substantial proportion of the elderly population.1 PAD leads to arterial stenosis and occlusions in the major vessels supplying the lower extremities. The impaired blood flow can lead to gangrene, and amputation may follow. Major amputation includes amputations above or below the knee and transmetatarsal amputation of the foot; toe amputation is considered a minor amputation.2
In 2005, 1.6 million persons in the United States were living with a major limb amputation.3 Of these individuals, 38% had an amputation secondary to PAD with a comorbid diagnosis of diabetes mellitus (DM).3 The number of toe amputations occurring each year in the US is unknown. Some international studies have reported declining rates of major amputations and increasing rates of minor amputations, a shift that may be due to improvements in preventive health care.4
Griffin et al5 define toe amputation as a minor surgical procedure; there is a paucity of data on the long-term outcomes of patients undergoing toe amputation. Their retrospective chart review5 of 63 patients undergoing toe amputations for vascular risk factors and comorbidities and the correlation of additional limb loss found 35 (55.6%) went on to have an additional amputation, including 22 major amputations (16 below-knee and 6 above-knee amputations) and 13 minor amputations; 43 patients (68.3%) had DM and 31 (49.2%) had 1 or more revascularization procedures. A significant correlation was noted between patients who did not have DM and additional limb loss (chi-squared = 4.31; P = .038); however, no other risk factor was identified that predicted the need for major amputation. The authors noted that at their facility it is standard practice for all patients with DM to be seen regularly in a multidisciplinary diabetic foot clinic, although this service was not available to patients with only the diagnosis of PAD.5
Research studies on health-related quality of life (HRQoL) after toe amputation with or without PAD have not been published. Evaluating HRQoL in individuals with PAD and toe amputations could lead to interventions tailored to address the specific HRQoL concerns of these individuals. Unfortunately, the number of items requiring a response in most HRQoL instruments makes their use in the clinical setting very time-consuming. The ideal HRQoL instrument should be valid and reliable, aimed at a seventh or eighth grade reading level, have a limited number of items, and be easy to complete.
In their effort to develop a disease-specific quality-of-life (QoL) tool for patients with PAD, Morgan et al6 describe the development and testing of a Vascular Quality of Life (VascuQoL) instrument for patients with PAD. The first phase consisted of item generation and pretesting in patients with PAD. Items with the highest clinical impact factor (ie, ability to walk, pain in legs/feet, worry about poor circulation in legs, ability to participate in social activities) were used to formulate a 25-item questionnaire that was pretested in 20 patients with PAD. The 25 items were divided into 5 subscales: pain (4 items), symptoms (4 items), activities (8 items), social (2 items), and emotional (7 items), with each question measured on a 7-point Likert scale ranging from 1 (worst HRQoL) to 7 (best HRQoL); total scores range from 25 to 175 and higher scores indicate better QoL. Reliability, internal consistency, responsiveness, and validity of the questionnaire were tested on 39 patients with PAD at 2 separate clinic visits 4 weeks apart. Test-retest scores showed a reliability of r >0.90. Each item had internal consistency (Cronbach α = .7-.9). The questionnaire showed face and construct validity.
Nordanstig et al7 developed a shorter version of the VascuQoL-25 — the VascuQol-6 — to make it a more practical option for use in vascular clinics. They recruited 200 PAD patients from 2 university hospitals. All patients completed the VascuQoL-25 when initially evaluated for PAD treatment and 127 completed it 6 months later after receiving treatment for PAD. The VascuQoL-25 was reduced to 6 questions based on patient interviews and psychometric testing; this new version (the VascuQol-6) was tested using item-response theory, exploring structure, precision, item fit, and targeting. The correlation between the VascuQoL-25 and the VascuQoL-6 was r = 0.88 before intervention and r = 0.96 after intervention; the difference was r = 0.91 (P <.001). The Cronbach α for the VascuQoL-6 was .85 before and .94 after intervention. Cognitive interviews of 15 patients indicated they considered all 6 items to be relevant and understandable. Rasch analysis7 was used to reduce the number options for each question from 7 (VascuQoL-25) to 4 (VascuQoL-6).
Kumlien et al8 administered the VascuQol-6 and the Short Form Health Survey-36 (SF-36) to 200 patients treated at 2 vascular centers in Sweden to explore both the validity and the reliability of the VascuQol-6 in the target population. Among the 200 patients, 150 also received a second VascuQol-6 for a test-retest assessment. In addition, a sample of 22 PAD patients consented to participate in cognitive interviews. The questionnaire data were tested by both Rasch analysis and traditional psychometric methods. Validity and reliability of the VascuQol-6 was high and a good fit to the Rasch model. Internal consistency and significant correlations between comparable dimensions in SF-36 were demonstrated. In the test-retest analysis, the percentage agreement was somewhat poor (<70%) among the 6 items. However, no systematic disagreements between the 2 assessments were noted in any of the 6 items, and the test-retest assessment for the VascuQol-6 sum score showed an acceptable intraclass correlation coefficient (0.86). All items in the VascuQol-6 were considered understandable and relevant by the interviewed patients. The VascuQol-6 also has been tested for validity and reliability in additional countries such as Norway9 and Brazil.10
The purpose of this descriptive, cross-sectional study was to evaluate HRQoL issues using the VascuQol-6 tool among patients with PAD who had undergone toe amputations.