Diagnostic Yield of Screening for Type 2 Diabetes in High-Risk Patients A Systematic Review

,

Original Research

Diagnostic Yield of Screening for Type 2 Diabetes in High-Risk Patients A Systematic Review

J Fam Pract. 1999 October;48(10):805-810

References

1. American Diabetes Association. Direct and indirect costs of diabetes in the United States in 1993. Alexandria, Va: American Diabetes Association; 1993.

2. Harris MI, Flegal KM, Cowie CC, et al. Prevalence of diabetes, impaired fasting glucose, and impaired glucose tolerance in U.S. adults: the third national health and nutrition examination survey, 1988-1994. Diabetes Care 1998;21:518-24.

3. Worrall G. Screening healthy people for diabetes: is it worthwhile? J Fam Pract 1991;33:155-60.

4. Newman WP, Nelson R, Scheer K. Community screening for diabetes. Low detection rate in a low-risk population. Diabetes Care 1994;17:363-5.

5. Bourn D, Mann J. Screening for noninsulin dependent diabetes mellitus and impaired glucose tolerance in a Dunedin general practice: is it worth it? NZ Med J 1992;105:207-10.

6. American Diabetes Association. Screening for type 2 diabetes. Diabetes Care 1998;21(suppl 1):S20-2.

7. Paterson R. Population screening for diabetes mellitus. Diabet Med 1993;10:777-81.

8. World Health Organization Study Group on Prevention of Diabetes Mellitus. Prevention of diabetes mellitus. Geneva, Switzerland: World Health Organization; 1994 (Technical Report Series, no. 844).

9. US Preventive Services Task Force. Guide to clinical preventive services. 2nd ed. Baltimore, Md: Williams & Wilkins; 1996.

10. Canadian Task Force on the Periodic Health Examination. The periodic health examination. Can Med Assoc J 1979;121:1193-254.

11. Jaeschke R, Guyatt G, Sackett DL. Users’ guide to the medical literature. III. How to use an article about a diagnostic test. A. Are the results of the study valid? JAMA 1994;271:389-91.

12. Duncan WE, Linville N, Clement S. Assessing risk factors when screening for diabetes mellitus. Diabetes Care 1993;16:1403-4.

13. American Diabetes Association. Are you at risk for diabetes? Diabetes Forecast 1993;46:55.-

14. McGregor MS, Pinkham C, Ahroni JH, Herter CD, Doctor JD. The American Diabetes Association risk test for diabetes: is it a useful screening tool? Diabetes Care 1995;18:585-6.

15. Burden ML, Burden AC. The American Diabetes Association screening questionnaire for diabetes: is it worthwhile in the U.K.? Diabetes Care 1994;17:97-8.

16. Herman WH, Smith PJ, Thompson TJ, Engelgau MM, Aubert RE. A new and simple questionnaire to identify people at increased risk for undiagnosed diabetes. Diabetes Care 1995;18:382-7.

17. National Center for Health Statistics. Plan and operation of the second national health and nutrition examination survey. Vital Health Stat 1 Washington, DC: US Government Printing Office; 1981 (Department of Health and Human Services publication no. 81-1317).

18. Barriga KJ, Hamman RF, Hoag S, Marshall JA, Shetterly SM. Population screening for glucose intolerant subjects using decision tree analysis. Diabetes Res Clin Pract 1996;34(suppl):S17-29.

19. Azzopardi J, Fenech FF, Junoussov Z, Mazovetsky A, Olchanski V. A computerized health screening and follow-up system in diabetes mellitus. Diabet Med 1995;12:271-6.

20. Ruige JB, De Neeling JND, Kostense PJ, Bouter LM, Heine RJ. Performance of an NIDDM screening questionnaire based on symptoms and risk factors. Diabetes Care 1997;20:491-6.

21. UK Prospective Diabetes Study 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 1998;352:837-53.

22. Jaeschke R, Guyatt G, Sackett DL. Users’ guide to the medical literature. III. How to use an article about a diagnostic test. B. What are the results and will they help me in caring for my patients? JAMA 1994;271:703-7.

Discussion

Several aspects of the diagnosis and care of patients with type 2 diabetes remain controversial and are the subjects of intensive research. It is unclear, for example, whether early identification through screening influences the course of diabetes and its complications. Evidence has only recently emerged that suggests that intensive treatment of type 2 diabetes prevents complications.²¹ These unresolved issues aside, the accurate identification of cases is a significant goal among clinicians.

Though the strategy of identifying and screening only high-risk individuals is widely recommended and practiced, there is little research to prove its effectiveness.

The results presented in the 7 papers do not make a convincing case for using the assessment of risk factors alone or in combination with typical symptoms as a screening tool. The LR+s of the studies fall between 1.05 and 2.22, meaning that screening only high-risk patients may modestly raise the post-test probability of diabetes.²² Similarly, the LR-s of 0.92 to 0.20 indicate that assessing and screening high-risk patients is only slightly helpful in ruling out disease. It seems that screening on the basis of risk factors is not useful. Together with the widely held view that universal screening is inefficient, we are left without an answer to the question of who should undergo blood glucose testing.

Implications for further research

It would be interesting to test Ruige and coworkers’ self-reporting questionnaire in a population that includes large numbers of minority groups at high risk. The diagnostic yield of a risk and symptom assessment instrument in such a population may be higher. Alternatively, a new risk and symptom assessment instrument could be developed and prospectively evaluated in the American population. Ideally, a study using such an instrument would include long-term follow-up of patients, not only to verify the presence or absence of diabetes, but also to see whether use of the instrument has any impact on morbidity and mortality resulting from this disease.

Assessing risk factors and performing blood glucose testing in only high-risk patients to identify type 2 diabetes is not recommended. The best way to identify new cases is unclear at this point. Blood glucose testing can be offered to patients who present with typical symptoms of diabetes.