Diabetes Care
HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
QUICK SEARCH:   [advanced]


     

This Article
Right arrow Extract Freely available
Right arrow Full Text (PDF)
Right arrow Purchase Article
Right arrow View Shopping Cart
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrow Request Permissions
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Herman, W. H.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Herman, W. H.
Social Bookmarking
Add to CiteULike   Add to Del.icio.us   Add to Digg   Add to Reddit   Add to Technorati  
What's this?
Diabetes Care 28:1480-1481, 2005
© 2005 by the American Diabetes Association, Inc.

Clinical Care/Education/Nutrition
Brief Report

Underdiagnosis of Peripheral Neuropathy in Type 2 Diabetes

William H. Herman, MD, MPH1, Laurence Kennedy, MD, RCP2 for the GOAL A1C Study Group

1 Department of Internal Medicine and Epidemiology, University of Michigan Medical Center, Ann Arbor, Michigan
2 Division of Endocrinology, University of Florida, Gainesville, Florida

Address correspondence and reprint requests to William H. Herman, MD, MPH, Department of Internal Medicine & Epidemiology, University of Michigan Health System, 1500 East Medical Center Dr., 3920 Taubman Center, Ann Arbor, MI 48109-0354. E-mail: wherman{at}umich.edu


   INTRODUCTION
TOP
 INTRODUCTION
RESEARCH DESIGN AND METHODS
 RESULTS
 CONCLUSIONS
 References
 
Diabetic peripheral neuropathy and its late sequelae cost >$4 billion annually in the U.S. (1). Improved glycemic control, early detection, and preventive care can prevent or delay adverse outcomes (2–4). An annual foot exam, which may include monofilament testing, is recommended by the American Diabetes Association (5). Unfortunately, neuropathy screening is underutilized in primary care practice (6,7). The GOAL A1C (Glycemic Optimization with Algorithms and Labs At Po1nt of Care) study assessed methods of A1C testing and insulin titration monitoring strategies in a large nationwide sample of predominantly primary care patients with type 2 diabetes. At baseline, physician perception of the presence of neuropathy was assessed via a survey before monofilament testing. A comparison between physician perception and monofilament testing is reported.


   RESEARCH DESIGN AND METHODS
TOP
 INTRODUCTION
 RESEARCH DESIGN AND METHODS
RESULTS
 CONCLUSIONS
 References
 
GOAL A1C was a randomized, open-label, parallel, four-arm study that compared the impact of point of care versus laboratory A1C testing and weekly versus less frequent insulin titration monitoring on glycemic control in patients with type 2 diabetes adding insulin glargine to existing oral antidiabetic therapy. Eligible patients were aged ≥18 years, inadequately controlled on oral antidiabetic agents (A1C >7.0%), and candidates for insulin. All signed informed consent and were randomized.

During the pretreatment phase, physician perception of neuropathy was assessed: physicians responded "yes" or "no" (without prompting) to a survey question, "Does subject have or has (this subject) had clinically significant neuropathy?" Monofilament testing was then conducted by the same physician.

Two monofilaments (3.61 and 5.07) were used. Before testing, patients felt the monofilament on their hands. During testing, monofilaments were applied (each up to three times) in random sequence to the plantar surface of the great toe on one foot with enough force to bend the monofilament. With eyes closed, patients indicated when a touch occurred. Results were scored as follows: no neuropathy = feels both monofilaments, mild/moderate = feels the 5.07 but not the 3.61 monofilament, severe (insensate foot) = unable to feel either monofilament, and nonsense result = feels the 3.61 but not the 5.07 monofilament.

Comparisons of baseline patient characteristics and neuropathy were performed with ANOVA (continuous variables) and {chi}2 tests (categorical variables). Explanatory effects of characteristics on neuropathy type were explored using logistic regression with backward selection. Comparison of correct diagnoses between endocrinologists and nonendocrinologists was performed with a Cochran-Mantel-Haenszel test, stratifying by neuropathy type.


   RESULTS
TOP
 INTRODUCTION
 RESEARCH DESIGN AND METHODS
 RESULTS
CONCLUSIONS
 References
 
There were 7,892 patients enrolled from 2,142 U.S. sites. Baseline data were available for 7,378 patients (93.5%). Mean age was 57 years, duration of diabetes was 8 years, and average baseline A1C was 8.9%. Physicians reported an 18% prevalence of neuropathy. Subsequent monofilament testing detected no neuropathy in 63%, mild/moderate neuropathy in 30%, and severe neuropathy in 7% of patients. Physician perception and monofilament testing were concordant in 14% of patients (n = 1,042).

Physicians prospectively identified only 31 and 66% of patients with mild/moderate and severe neuropathy, respectively (Table 1). Nonendocrinologists (90% of investigators; n = 2,297) correctly identified mild/moderate and severe neuropathy in 31 and 64% of patients, respectively. Endocrine specialists (10% of investigators; n = 258) correctly identified mild/moderate and severe neuropathy in 36 and 74% of patients, respectively (P < 0.0001 for correct diagnoses by endocrinologists compared with nonendocrinologists).


View this table:
[in this window]
[in a new window]
  		Table 1— Comparison of point-of-care monofilament testing and clinical diagnosis of neuropathy (n = 7,378)

 
By regression analysis, aged ≥50 years (odds ratio [OR] 1.58), male sex (OR 1.17), diabetes duration >7 years (OR 1.29), feeling "pins and needles" (OR 2.91), history of foot ulcers (OR 5.20), and height ≥1.7 m (OR 1.43) were significantly associated with neuropathy (P = 0.0440 for male sex; P < 0.0001 for other characteristics). Weight and A1C level were not associated with neuropathy. Patients with severe neuropathy were more likely to report experiencing feelings of "pins and needles," a history of foot ulcers, and being prescribed custom footwear than were patients with mild/moderate neuropathy or no neuropathy.


   CONCLUSIONS
TOP
 INTRODUCTION
 RESEARCH DESIGN AND METHODS
 RESULTS
 CONCLUSIONS
References
 
Monofilament testing is a simple noninvasive independent predictor of risk for foot lesions (8,9). Monofilament testing detected a 37% prevalence of neuropathy in patients with type 2 diabetes in our large nationwide sample, which is more than twice the prevalence identified by physicians before testing. Physicians detected a greater proportion of severe neuropathy than mild/moderate neuropathy.

Despite the established relationship between glycemic control and neuropathy (4,10), we did not identify A1C as a risk factor. Use of a single A1C measurement and exclusion of patients with A1C <7.0% could have masked an association (9).

Our study had a number of limitations. Definitive diagnostic studies to confirm neuropathy were not conducted. We employed a nonstandard protocol for monofilament testing but used it to minimize variability among the >2,000 investigators who participated. Restricting testing to one side may have favored inclusion of some cases of secondary mononeuropathy unrelated to diabetes. Testing the dorsum of the big toe or testing multiple sites (8,11) might have increased sensitivity. It is important to consider, however, that single-site screening may be more feasible in busy clinical practice and appears to improve detection.

Overall, physicians underestimate neuropathy in many patients with type 2 diabetes who are under their care and thus may be missing potential opportunities for early intervention. Systematic monofilament testing can facilitate earlier diagnosis and appropriate preventive care to reduce adverse outcomes.


   Acknowledgments
 
This study was sponsored by Aventis Pharmaceuticals, which was involved in design, conduct, data collection, and analysis.

The primary authors participated in design and monitoring, controlled data evaluation/interpretation, and prepared the manuscript. Data from this study have been published in abstract form (Diabetes 52 [Suppl. 1]:A193, 2003). The authors express gratitude to Debra Schleusener for statistical analysis.


   Footnotes
 
L.K. has served on advisory boards for Aventis and Sanofi-Aventis and has received honoraria from Aventis.

A table elsewhere in this issue shows conventional and Système International (SI) units and conversion factors for many substances.

Received for publication January 13, 2005. Accepted for publication March 12, 2005.


   References
TOP
 INTRODUCTION
 RESEARCH DESIGN AND METHODS
 RESULTS
 CONCLUSIONS
 References
 

  1. Gordois A, Scuffham P, Shearer A, Oglesby A, Tobian JA: The health care costs of diabetic peripheral neuropathy in the U.S. Diabetes Care 26:1790–1795, 2003[Abstract/Free Full Text]
  2. Hogan P, Dall T, Nikolov P, American Diabetes Association: Economic costs of diabetes in the U.S. in 2002. Diabetes Care 26:917–932, 2003[Abstract/Free Full Text]
  3. Diabetes Control and Complications Trial Research Group: Effect of intensive diabetes treatment on nerve conduction in the Diabetes Control and Complications Trial. Ann Neurol 38:869–880, 1995[Medline]
  4. UK Prospective Diabetes Study (UKPDS) Group: Intensive blood-glucose control with sulphonylureas or insulin compared with conventional treatment and risk of complications in patients with type 2 diabetes (UKPDS 33). Lancet 352:837–853, 1998[Medline]
  5. American Diabetes Association: Standards of medical care in diabetes (Position Statement). Diabetes Care 27 (Suppl. 1):S15–S35, 2004
  6. Kirkman MS, Williams SR, Caffrey HH, Marrero DG: Impact of a program to improve adherence to diabetes guidelines by primary care physicians. Diabetes Care 25:1946–1951, 2002[Abstract/Free Full Text]
  7. O’Brien KE, Chandramohan V, Nelson DA, Fischer JR Jr, Stevens G, Poremba JA: Effect of a physician-directed educational campaign on performance of proper diabetic foot exams in an outpatient setting. J Gen Intern Med 18:258–265, 2003[Medline]
  8. Jirkovská A, Boucek P, Wosková V, Bartos V, Skibova J: Identification of patients at risk for diabetic foot: a comparison of standardized noninvasive testing with routine practice at community diabetes clinics. J Diabetes Complications 15:63–68, 2001[Medline]
  9. Rahman M, Griffin SJ, Rathmann W, Wareham NJ: How should peripheral neuropathy be assessed in people with diabetes in primary care? A population-based comparison of four measures. Diabet Med 20:368–374, 2003[Medline]
  10. The Diabetes Control and Complications Trial Research Group: The effect of intensive treatment of diabetes on the development and progression of long-term complications in insulin-dependent diabetes mellitus. N Engl J Med 329:977–986, 1993[Abstract/Free Full Text]
  11. Abbott CA, Carrington AL, Ashe H, Bath S, Every LC, Griffiths J, Hann AW, Hussein A, Jackson N, Johnson KE, Ryder CH, Torkington R, Van Ross ER, Whalley AM, Widdows P, Williamson S, Boulton AJ: The North-West Diabetes Foot Care Study: incidence of, and risk factors for, new diabetic foot ulceration in a community-based patient cohort. Diabet Med 19:377–384, 2002[Medline]

Add to CiteULike CiteULike   Add to Del.icio.us Del.icio.us   Add to Digg Digg   Add to Reddit Reddit   Add to Technorati Technorati    What's this?


This article has been cited by other articles:


Home page
 Diabetes CareHome page
B. A. Perkins, A. Orszag, J. Grewal, E. Ng, M. Ngo, and V. Bril
Multi-Site Testing With a Point-of-Care Nerve Conduction Device Can Be Used in an Algorithm to Diagnose Diabetic Sensorimotor Polyneuropathy
Diabetes Care, March 1, 2008; 31(3): 522 - 524.
[Abstract] [Full Text] [PDF]

Home page
 Am J EpidemiolHome page
Y. J. Cheng, E. W. Gregg, H. S. Kahn, D. E. Williams, N. De Rekeneire, and K. M. V. Narayan
Peripheral Insensate Neuropathy--A Tall Problem for US Adults?
Am. J. Epidemiol., November 1, 2006; 164(9): 873 - 880.
[Abstract] [Full Text] [PDF]

Home page
 Diabetes CareHome page
B. A. Perkins, J. Grewal, E. Ng, M. Ngo, and V. Bril
Validation of a Novel Point-of-Care Nerve Conduction Device for the Detection of Diabetic Sensorimotor Polyneuropathy.
Diabetes Care, September 1, 2006; 29(9): 2023 - 2027.
[Abstract] [Full Text] [PDF]

Home page
 DOC NewsHome page
E. Heubeck
New Treatment Options for Diabetic Neuropathy
DOC News, February 1, 2006; 3(2): 8 - 9.
[Full Text]

This Article
Right arrow Extract Freely available
Right arrow Full Text (PDF)
Right arrow Purchase Article
Right arrow View Shopping Cart
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrow Request Permissions
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Herman, W. H.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Herman, W. H.
Social Bookmarking
Add to CiteULike   Add to Del.icio.us   Add to Digg   Add to Reddit   Add to Technorati  
What's this?

HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
Diabetes Diabetes Care Clinical Diabetes Diabetes Spectrum