Relation of lower-extremity amputation to all-cause and cardiovascular disease mortality in American Indians: the Strong Heart Study.
ABSTRACT To compare risk of all-cause and cardiovascular disease (CVD) mortality in people with a lower-extremity amputation (LEA) attributable to diabetes and people without an LEA.
The Strong Heart Study is a study of CVD and its risk factors in 13 American-Indian communities. LEA was ascertained at baseline by direct examination of the legs and feet. Mortality surveillance is complete through 2000.
Of 2,108 participants with diabetes at baseline, 134 participants (6.4%) had an LEA. Abnormal ankle-brachial index (53%), albuminuria (87%), and long diabetes duration (mean 19.8 years) were common among diabetic subjects with LEA. Mean diabetes duration among diabetic participants without LEA and in those with toe and below-the-knee amputations was 11.9, 18.6, and 21.1 years, respectively. During 8.7 (+/-2.9) years of follow-up, 102 of the participants with LEA (76%) died from all causes and 35 (26%) died from CVD. Of the 1,974 diabetic participants without LEA at baseline, 604 (31%) died from all causes and 206 (10%) died from CVD. The unadjusted hazard ratios (HRs) for all-cause and CVD mortality in diabetic participants with LEA compared with those without were 4.0 and 4.1, respectively. Adjusting for known and suspected confounders, LEA persisted as a predictor of all-cause (HR 2.2, 95% CI 1.7-2.9) and CVD mortality (HR 1.9, 95% CI 1.3-2.9). We observed a significant interaction between baseline LEA and sex on CVD mortality, with female sex conferring added risk of CVD mortality.
LEA is a potent predictor of all-cause and CVD mortality in diabetic American Indians. The combination of female sex and LEA is associated with greater risk of CVD mortality than either factor alone.
Article: Improved survival of diabetic foot ulcer patients 1995-2008: possible impact of aggressive cardiovascular risk management.[show abstract] [hide abstract]
ABSTRACT: The purpose of this study was to determine whether a strategy of aggressive cardiovascular risk management reduced the mortality associated with diabetic foot ulceration. After an initial audit of outcomes demonstrating a high mortality rate in 404 diabetic foot ulcer patients with the first ulceration developing between 1995 and 1999, a new aggressive cardiovascular risk policy was introduced as standard practice at the Diabetic Foot Clinic, Royal Infirmary of Edinburgh, in 2001. In the first 3 years of this policy, 251 patients were screened and identified. The audit cycle was then closed by reauditing the 5-year mortality for this second group of foot ulcer patients in 2008. Overall 5-year mortality was reduced from 48.0% in cohort 1 to 26.8% in cohort 2 (P < 0.001). Improvement in survival was seen for both neuroischemic patients (5-year mortality of 58% reduced to 36%; relative reduction 38%) and neuropathic patients (36% reduction to 19%; relative reduction 47%) (both P < 0.001). Patients were more likely to die if they were older at the time of ulceration or had type 2 diabetes, renal impairment, or preexisting cardiovascular disease or were already taking aspirin. Prior statin use, current smoker or ex-smoker status, blood pressure, A1C, and total cholesterol were not significantly different between survivors and those who died in the follow-up periods. Diabetic foot ulcer patients have a high risk of death. Survival has improved over the past 13 years. The adoption of an aggressive cardiovascular risk management policy in diabetic foot ulcer clinics is recommended for these patients.Diabetes care 08/2008; 31(11):2143-7. · 8.09 Impact Factor
Article: All-cause mortality after diabetes-related amputation in Barbados: a prospective case-control study.[show abstract] [hide abstract]
ABSTRACT: To determine the mortality rate after diabetes-related lower-extremity amputation (LEA) in an African-descent Caribbean population. We conducted a prospective case-control study. We recruited case subjects (with diabetes and LEA) and age-matched control subjects (with diabetes and no LEA) between 1999 and 2001. We followed these groups for 5 years to assess mortality risk and causes. There were 205 amputations (123 minor and 82 major). The 1-year and 5-year survival rates were 69 and 44% among case subjects and 97 and 82% among control subjects (case-control difference, P < 0.001). The mortality rates (per 1,000 person-years) were 273.9 (95% CI 207.1-362.3) after a major amputation, 113.4 (85.2-150.9) after a minor amputation, and 36.4 (25.6-51.8) among control subjects. Sepsis and cardiac disease were the most common causes of death. These mortality rates are the highest reported worldwide. Interventions to limit sepsis and complications from cardiac disease offer a huge potential for improving post-LEA survival in this vulnerable group.Diabetes care 12/2008; 32(2):306-7. · 8.09 Impact Factor
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ABSTRACT: BACKGROUND: Diabetes is a major cause of morbidity and mortality in the United States, with much of the economic and social costs related to macrovascular and microvascular complications, such as myocardial infarctions, renal failure, and lower extremity amputations. While racial/ethnic differences in diabetes are well documented, less attention has been given to differences in diabetes outcomes by gender. QUESTIONS/PURPOSES: Does gender influence the rate of diabetes-related lower extremity amputations and/or the rate of mortality after amputation? METHODS: I reviewed the literature utilizing peer-reviewed publications found through MEDLINE searches. WHERE ARE WE NOW?: Major complex gender differences exist in diabetes-related lower extremity amputations: men are more likely to undergo lower extremity amputations, but women apparently have higher mortality related to these procedures. The reasons for such differences are not entirely clear, but it appears biologic factors may play important roles (increased rates of peripheral vascular disease and peripheral neuropathy in men, interaction between gender and cardiac mortality in women). WHERE DO WE NEED TO GO?: More research is warranted to confirm gender differences in diabetes-related lower extremity amputation mortality and explore underlying mechanisms for the gender differences in lower extremity amputations and its associated mortality. HOW DO WE GET THERE?: Exploring gender disparities in diabetes-related outcomes, such as lower extremity amputations, will need to become a national priority from a research (eg, National Institutes of Health) and policy (eg, Centers for Medicare and Medicaid Services) perspective. Only when we have a better understanding of the causes of such differences can we begin to make strides in addressing them.Clinical Orthopaedics and Related Research 12/2010; 469(7):1951-5. · 2.53 Impact Factor