Alarmingly high mortality rates have been reported in diabetic patients with ulcerations—especially if complicated by amputation. In a recent issue of Diabetes Care, Hambleton et al. (1) raise the possibility of a “different hierarchy” of postamputation complications and causes of death in patients with diabetes from developed and developing areas of the world, comparing their data with published work from the U.S. (2).
To examine this further we have analyzed data from a cohort of German and Tanzanian patients in an ongoing multinational follow-up study of diabetic foot ulcer patients (3) and compared them with the patients of Hambleton et al. Diabetic foot patients from Germany and Tanzania were included in a prospective study conducted between 1998 and 1999. Initial results of this study showed significant differences in age at the onset of first foot ulcer and in prevalence of coronary heart disease, stroke, and peripheral arterial disease (3). Our conclusion from the short-term results was that favorable outcomes in populations from industrialized nations seem to be closely linked to the presence and management of peripheral arterial disease, whereas uncontrolled infections appear to be the major problem in developing countries, as reflected by high amputation rates in the absence of evident vascular disease (4).
Five-year follow-up data from this study were evaluated for available German and Tanzanian patients. The survival rates at 6, 12, and 60 months were 96, 87, and 42%, respectively, in the German cohort and 75, 75, and 50% in the Tanzanian cohort for patients suffering minor amputation. The rates following major amputation were 78, 61, and 11% (Germany) and 75, 62, and 12% (Tanzania). In the Barbadian cohort the corresponding numbers were 86, 81, and 59% for minor and 57, 49, and 21% for major amputees.
The direct causes of death in the patients from Barbados were due to stroke (10%), cardiac disease (25%), and sepsis (27%). In the German cohort, 10% were related to stroke and 60% to cardiac disease but only 3% directly to sepsis. By contrast in the Tanzanian cohort sepsis was responsible for 52% of the deaths that occurred within 5 years, while cardiac events and stroke combined caused only 19%. Comparing the causes of deaths, Barbados seems to take an intermediate position between Germany and Tanzania. This placement of Barbados in the middle of a spectrum from developing to industrialized countries is a model that has previously been used in investigating hypertension and obesity in the International Collaborative Study on Hypertension in Blacks (5) and also correlates with the relative positions these countries occupy in the human development index (Germany: position 22, human development index 0.935; Barbados: 31, 0.892; Tanzania: 159, 0.467; http://hdr.undp.org/en).
To conclude, a comparison of our data with those from the study of Hambleton et al. supports the speculation that a different hierarchy between industrialized and developing countries is not only obvious for risk factors for (3) and outcome predictors of (4) diabetic foot lesions but might also be true for postamputation complications leading to the death of those patients. The situations in threshold countries and newly industrialized countries, however, contain aspects of both developing and industrialized nations.
Acknowledgments
No potential conflicts of interest relevant to this article were reported.
