Prospective Observation Study of Patient Outcome and Cost Effectiveness of Interventions for Critical Ischemia

Prospective Observation Study of Cost Effectiveness of Interventions for Critical Ischemia

Background The incidence of arteriosclerotic disease increases with age and is one of society's greatest public health problem. Impaired circulation to the lower limbs, termed peripheral arterial disease (PAD) is a common diagnosis in the older populations. Estimates show that about 10% of the population over age 70 suffers from symptomatic PAD. [1] Milder forms of the disease causes walking induced pain in the legs, termed intermittent claudication, resulting in a variable restriction of walking ability. As the disease progresses, circulatory impairment becoming more pronounced, often resulting in rest pain, impaired wound healing, or in the worst cases gangrene. These latter stages of PAD categorized as critical limb ischemia, is usually followed by a pronounced reduction in the individual's mobility and quality of life. The incidence of critical limb ischemia in Sweden is estimated at about 40 per 100 000 inhabitants, which means that each year more than 600 individuals in the Västra Götaland Region (VGR) suffer from this condition. [2] Untreated critical ischemia leads to a high risk of amputations. Investigations of the blood circulation of these patients arterial circulation generally reveal extensive arteriosclerotic vascular lesions including arterial occlusions (stop) in the vessels supplying the lower extremities. Interventions designed to improve blood flow has ability to reduce symptoms and in the short or long term eliminate amputation threat. The established treatment principle has since the 1960s been bypass surgery. The method involves major open surgery, including a period of hospitalization and has a high incidence of local as well as general complications.

Since more than a decade, a minimally invasive technique to restore flow in occluded artery has become widely used. The method termed as subintimal angioplasty (SAP) uses catheter and guide wire to get through the occluded vessel section, followed by balloon dilatation. The method is under development and increases in use both internationally and in Sweden. The advantage is that the procedure has less risk for local and systemic complications. The procedures is also associated with shorter hospital stays. Disadvantages are that the duration of treatment is often shorter and the procedure often has to be repeated. [3] It is currently unknown if Endovascular intervention is a cost effective way to treat critical limb ischemia. Furthermore, the impact on patient health-related quality of life (HRQL) is in the short and long term unknown. What role the minimally invasive technologies will have in the future is unclear, mainly due to that efficiency and cost-effectiveness compared to bypass surgery have not thoroughly been evaluated, which was pointed out in a national health technology assessment "Benartärsjukdom - diagnosis and treatment". [1]

Purpose The purpose of this study is to evaluate the effectiveness, cost efficiency, and patient benefits including HRQL in the short and long term for the two principally different methods of treatment for critical limb ischemia in as far as possible unselected clinical population of VGR. The effectiveness of treatment methods are evaluated for their ability to prevent amputations, provide symptom improvement, duration of treatment (patency), cumulative health care cost up to two years, and the effects on HRQL.

Question / Hypothesis