Cath Lab Digest

People in the US are living longer. In 1900, 65-year-old persons were expected to live an additional 12 years and 85-year-old persons another 4 years. By 2001, life expectancy at age 65 had increased to more than 84 years for women and about 81 years for men and at age 85, women and men were expected to live another 7 and 6 years, respectively.¹ The number of young-old (age 65 to 74 years) and old-old (age 75 and older) is ever increasing.^2,3

In 2005, 20.8 million people in the US (7% of the population) had diabetes.⁴ Of these people, an estimated 6.2 million are undiagnosed. The estimated total prevalence of diabetes among people age 60 years or older in 2005 was 10.3 million.⁴ That same year, approximately 575,000 new cases of diabetes were diagnosed among US adults age 60 years and older4; of all people in this age group (60 years or older), 20.9% are estimated to have diabetes (see Figure 1).

As the prevalence of diabetes increases, so will the number of people with its complications. In 2001, 42,813 people with diabetes began treatment for end-stage renal disease.⁵ Diabetic retinopathy causes 12,000 to 24,000 new cases of blindness each year.⁵ In 2002, approximately 82,000 nontraumatic lower-limb amputations were performed among people with diabetes.⁵ Heart disease death rates are two to four times higher among adults with diabetes than adults without the disease.⁵ Economic costs and projections increase along with diabetes complications. The total estimated cost of diabetes in the US in 2002 was $132 billion, comprised of $92 billion for direct medical costs and $40 billion for indirect costs (disability, work loss, and premature mortality).⁵

A review of data from the 1996–2002 National Hospital Discharge Survey⁴ found octogenarian patients (age ≥80) with diabetes had twice the risk for developing a lower extremity ulcer, three times the risk of developing a foot abscess, and four times the risk of developing osteomyelitis. Compared to patients of the same age without diabetes, the diabetic octogenarian is nearly twice as likely to undergo ulcer debridement and three to five times more likely to have a lower extremity amputation.⁶ In a population-based, 7-year follow-up study of 733 patients with diabetes (25 with lower extremity amputations), several factors that increased risk of amputation were identified.⁷ Compared to all patients without amputation, patients with amputation differed in 24 variables concerning diabetes and its complications⁷; factors relevant to the current discussion include increased age, a longer duration of diabetes, and having a visual handicap.⁷

The elderly constitute a large proportion of patients with diabetes who have amputations. In 1994, people older than 65 years with diabetes accounted for 55.3% of nontraumatic lower extremity amputations (LEA) in the US that year.⁸ In 2002, LEA rates among patients with diabetes age 65 to 74 and ≥75 years were 1.6 and 2.1 times higher, respectively, than rates among patients younger than 65 years. In 2002, the rate of hospital discharge for nontraumatic LEA per 1,000 persons with diabetes increased with age for all levels of amputation. The largest relative and absolute increase in LEA across age groups occurred for above knee LEA — the rate per 1,000 persons with diabetes increased from 0.5 among persons <65 years to 3.4 among persons age 75 years and older.⁵