Evaluation of
Diabetes-Related Complications

 

Furqan Siddiqui, MBChB^*

Siriporn Janchai, MD^†

Donald Mercante, PhD^‡

William Dabdoub, DPM^§

 

^*Assistant Professor/Director of Research, Department of Medicine, Section of Physical Medicine and Rehabilitation

^†Research Fellow, Department of Medicine, Section of Physical Medicine and Rehabilitation

^‡Associate Professor, Department of Public Health and Preventive Medicine

 Louisiana State University Health Sciences Center

 New Orleans, LA

^§Private Practice, New Orleans, LA

 

KEY WORDS: diabetes, foot ulcers, amputation, peripheral neuropathy

ABSTRACT

Long-term complications due to diabetes continue to be a major problem for patients with this disease. A study was conducted to evaluate the frequency of different diabetes-associated problems among the patients attending out-patient clinics at the Louisiana Rehabilitation Institute, New Orleans, LA. A total of 182 subjects, both men and women and from different ethnic backgrounds, were included in the study. A majority of patients were overweight or obese (80%) and had a family history of diabetes (79%). Most patients (86%) exhibited severe complications as a consequence of the disease. Two of the most common complications were peripheral neuropathy (68%) and problems related to the eyes (43%). Lower extremity ulcer as consequence of this disease was also found to be a common complication, occurring in nearly two-fifths of the patients (38.4%). Severity of the disease in given cases led to amputations of the lower extremities in more than a third of cases (39%). However, the majority of these individuals had early symptoms of peripheral neuropathy (81%) and lower extremity ulcer (89%). Thus, a program of early symptom detection and effective control of diabetes can be expected to reduce the incidence of diabetes-related complications. Furthermore, prevention and proper management of foot ulcers will reduce the risk of amputation in these patients.

INTRODUCTION

Diabetes continues to be the most common chronic disease in the developed countries, with more than 100 million cases diagnosed worldwide.1 Of these, approximately 16 million cases are in the United States, with nearly 800,000 new cases diagnosed each year.2,3 In Louisiana, the total number of adults diagnosed with diabetes in 1996 and 1997 was 187 and 191 per 1000 people, respectively.4 The serious implications of the disease are manifested by the fact that it is the third most common cause of death in the US.2 The associated long-term complications due to diabetes have been reported to cause problems in every major system of the body (cardiovascular, cerebrovascular, neurologic, renal) in patients with this disease. Consequently, we have a large population with debilitating conditions like myocardial infarction, stroke, renal failure, blindness, and non-traumatic lower extremity amputation.

In addition to these complications, a reported 5% to 10% of diabetic patients experience lower extremity ulceration. Approximate 1% undergo amputation, a rate 15 times higher than that in the nondiabetic population.5 Diabetic neuropathy has proven to be a major contributory factor in the pathogenesis of foot ulcers. The patients predominantly involved are the elderly (40%) with type 2 diabetes.6 In Louisiana, about 2,575 diabetic patients undergo lower extremity amputation each year as a result of ulceration induced by diabetes.3 Avoiding heightened morbidity and mortality and poor quality of life for these patients requires an early diagnosis and proper management, a major challenge to health care professionals working in this area.

STUDY DESIGN

The purpose of this study was to evaluate the frequency of diabetes-associated problems among patients attending out-patient clinics at the Louisiana Rehabilitation Institute in New Orleans. A questionnaire was given to patients while they were waiting to be seen. The questionnaire requested detailed information including demographics, medical and surgical history, duration of diabetes, and the type of treatment the patients received. Additional complication-related information was obtained during the medical examination.

RESULTS

This study included 182 patients, with an average age of 56.3 (± 11.3) years. Survey respondents were predominantly African American or Caucasian (24%). The majority of patients were classified as having type 2 diabetes (89%), and more than half of the study sample (52%) reported having had the disease for more than 10 years. Forty-eight percent of patients reported smoking on a regular basis; the average duration was 22 years. Approximately one-sixth of patients (17%) reported consuming alcohol on an infrequent basis. Table 1 summarizes the descriptive statistics of our study sample.

Peripheral neuropathy is the most common complication noted in our study. Lower extremity amputation was the most frequent procedure needed. Table 2 summarizes the major complications and surgeries that occurred secondary to diabetes-related complications. Peripheral neuropathy and eye problems were the most frequent complications, reported in 67.6% and 43.4% of patients, respectively. Amputation, the most often cited surgery, was performed in nearly two-fifths of patients (39%). Amputations were further classified as partial foot amputation (26%) and below and above the knee amputation (15%).

Among the total lower extremity amputation cases, 81% had peripheral neuropathy, 89% had foot ulcers, and 30% had peripheral vascular disease (PVD). Other common surgeries performed as a consequence of the disease were eye-related surgery (9.9%), limb vascular bypass surgery (4.9%), and coronary artery bypass surgery (3.8%). A significantly increasing trend between frequency of complications and duration of diabetes on the ordinal scale (less than or equal to 2, between 2 and 5, between 5 and 10, and more than 10 years) was found for peripheral neuropathy (P=0.001), diabetic foot ulcers (P =0.001), and eye problems (P =0.001) (Figure 1). A trend was also observed for the incidence of lower extremity amputations (P =0.08).

DISCUSSION

Over the years, obesity and diabetes have reached epidemic proportions and present a strong threat to the health of the American people. A recent study published by the Centers for Disease Control showed that among the general population in the US, more than 50% of adults are overweight and 22% exhibit obesity. Obesity trends in Louisiana have increased markedly, from 10% to 14% in 1990 to more than 20% by the year 2000. In the current study, 48% of patients were obese and 31% were overweight. These numbers indicate that obesity is more prevalent in our study population than in the general population. Several studies have shown a strong association between obesity and insulin resistance.7 Insulin resistance is a pathogenetic factor for type 2 diabetes and is also a risk factor for coronary artery disease.8 Diet and exercise remain important in combating these health issues. Reduced blood glucose levels, improved insulin sensitivity, and lower cholesterol levels can be achieved with an effective dietary and exercise program.9 Moreover, educating the general public and creating an environment of awareness about the disease is an essential tool for minimizing complications.

In our study population, 67% had attended formal diabetic educational classes and 72% reported involvement in regular exercise (usually walking). Health education, including nutrition and appropriate exercise, must be emphasized further to patients, with periodic re-evaluation of patient understanding and adherence. Educational information, including detailed descriptions (eg, type of food, total caloric intake, methods, duration, and exercise intensity) should be provided. In addition, patients with neuropathy and foot problems need specific exercise programs to achieve the best outcome.

Diabetes is the leading cause (more than 50%) of nontraumatic lower extremity amputation in the United States. Significant risk factors for amputation are hyperglycemia, a longer duration of diabetes, older age, and the presence of neuropathy, peripheral vascular disease, or foot ulcer. Foot ulcers alone precede about 85% of these amputations.11–13 Peripheral neuropathy can occur in both types of diabetes (60% to 70%), but more severe cases are found in patients with type 1 diabetes.10 It was the most common complication found in this study (68%).

The higher percentage of ulcer and amputation observed in our study may be attributed to the lower levels of education, low socioeconomic status, high rates of obesity, and high rates of non-adherence as compared with national levels. According to recently published data, intensive multidisciplinary team management can reduce up to 50% of neuropathic foot ulceration.14 Early detection and proper management of foot ulcer will further reduce the risk of amputation. Recently, the US Department of Health and Human Services called for a 40% overall reduction in lower extremity amputations, including a reduction in the amputation rate for African-Americans from 10.2 per 1,000 to 6.1 per 1,000 by the year 2010.

Another important complication is diabetic retinopathy. It is the leading cause of new blindness in adults in the US.15 About 20% of patients with NIDDM have evidence of diabetic retinopathy at diabetes diagnosis. After 20 years of diabetes, nearly all patients with type 1 and more than 60% of people with type 2 diabetes have some degree of retinopathy.16 Eye problems were the second most often reported major complication from this disease (43.4%). Aside from the obvious vision-related complications, eye problems can lead to worsening of foot problems. Patients with peripheral neuropathy need visual perception to normalize gait, avoid injury, and detect emerging foot ulcerations. Diabetic patients should have an initial dilated and comprehensive eye examination by an ophthalmologist at diagnosis of type 2 and within 3 to 5 years after onset of type 1 diabetes (but not before the age of 10 years).17 Furthermore, for patients with eye problems, daily foot care should be done by family members or other care givers.

CONCLUSION

A significant increasing trend in microvascular complications with duration of diabetes was found. In contrast, there was no indication that a similar trend exists for macrovascular complications. Among all the major complications, peripheral neuropathy is the most common and is the first one to be noted. It is the major etiologic factor for diabetic neuropathic foot ulcers. These ulcers are the leading cause of lower extremity amputation. A comprehensive program of early detection and effective control of the disease may reduce the incidence of diabetic-related complications. Furthermore, prevention and proper management of foot ulcer will reduce the risk of amputation in these patients.

References

1. Nathan DM, Meigs J, Singer DE: Lancet 350(suppl):4–9, 1997.

2. Center of Disease Control and Prevention: The public health of diabetes mellitus in the United States. Atlanta, GA: Department of Health and Human Services, 1997.

3. U.S. Department of Health and Human Services: Health people 2010: Understanding and Improving Health, Vol.1.Washington, DC, U.S. Dept. of Health and Human Services, Govt. Printing Office.January 2000, p. 5–22.

4. Centers for Disease Control and Prevention: National Center for Chronic Disease Prevention and Health Promotion. Washington, DC: Centers for Disease Control and Prevention; 2002.

5. Mayfield JA, Reiber GE, Sander LJ, Janisse D, Pogach LM: Preventative foot care in people with diabetes. Diabetes Care 21:2161–77, 1998.

6. Kumar S, Ashe H, Parnell L, et al: The prevalence of foot ulceration and its correlation in type 2 diabetic patients: A population-based study. Diabetic Med 11:480–84, 1994.

7. Ferrannini E, Natali A, Bell P, et al: Insulin resistance and hypersecretion in obesity. J Clin Invest 100:1166–73, 1997.

8. Zavorini I, Bonora E, Palliara M, et al: Risk factors for coronary artery disease in healthy person with hyperinsulinemia and normal glucose tolerance. N Engl J Med 320;702–6, 1989.

9. Hamdy O, Horton ES: Diet and exercise in type 2 diabetes mellitus. Endocrin Metab Clin North Am 30(4):883–907, 2001.

10. Eastman RC: Neuropathy in Diabetes. In Diabetes in America, 2nd ed. Washington, DC: National Institutes of Health, NIDDK, NIH.1995; pub.No.95–1468: 339–48.

11. Pecoraro RE, Reiber GE, Burgess EM: Pathway to diabetic limb amputation: Basis for prevention. Diabetes Care 13:513–21, 1990.

12. Reiber GE, Pecoraro RE, Koepsell TD: Risk factors for amputation in patients with diabetes mellitus: A case-control study. Ann Intern Med 117:97–105, 1992.

13. Larsson J: Lower extremity amputation in diabetic patients. Lund University, Doctoral Thesis, 1994.

14. Dargis V, Pantelejeva O, Jonushaite A, Veikyte L, Boulton KJM: Benefits of a multidisciplinary approach in the management of recurrent diabetic foot ulceration in Lithuania. Diabetes Care 22:1428–31, 1999.

15. Ajello LP, Gardner TW, King GI, et al: Diabetic retinopathy (technical review). Diabetes Care 21:143–56, 1998.

16. Diabetes Care. Diabetic Retinopathy 2000.

17. American Diabetes Association: Position Statement: Diabetic retinopathy. Diabetes Care 24(suppl1):S73–76, 2001.

 

 

 

Table 1. Characteristics of Study Participants

 

 

Characteristics     N                      Range                   Mean %                         SD

 

Age (y)              182                      14–88                       56.34                     11.25

Gender

  Male                   85                            —                         46.7                          —

  Female               97                            —                         53.3                          —

 

Race

  Black               133                            —                         73.1                          —

  White                 43                            —                         23.6                          —

  Other                   6                            —                           3.2                          —

 

Weight (pounds)  —                   112-400                     201.01                     47.25

 

BMI Classification

  Obese               88                            —                         48.4                          —

  Overweight       57                            —                         31.3                          —

  Normal               36                            —                         19.8                          —

  Underweight       1                            —                           0.5                          —

 

Height (inches)    —                      57–79                       67.66                       4.15

 

Type Diabetes

  Type I                20                            —                            11                          —

  Type II              162                            —                            89                          —

 

Family history of DM                     143                            —                            79                          —

 

Family history of HT                          135                            —                         74.6                          —

 

History of smoking                            87                            —                         47.8                          —

 

History of alcohol 30                            —                         16.5                        —

 

 

Table 2. Diabetes Related Complications

 

 

Overall diabetes-  

related complications        N                 Mean %

 

Major Complications
Related to Diabetes

  Peripheral neuropathy        123                       67.6

  Eye problems    79                       43.4

  Peripheral vascular disease 29                       15.9

  Cardiac problems                            25                      13.7

  Stroke                15                         8.2

  Renal problems 13                         7.1

 

Surgeries secondary to

diabetes related complications

  Amputation        70                       38.5

    Partial foot       48                       26.4

    BK-AK             28                       15.4

  Eye surgery      18                         9.9

  Limb vascular bypass                  9                         4.9

  Coronary artery bypass                  7                        3.8

 

 

Figure 1. Complications associated with the duration of diabetes.