Skip to main content
Log in

Prevalence of subclinical hypothyroidism in a population living in the Milan metropolitan area

  • Original Article
  • Published:
Journal of Endocrinological Investigation Aims and scope Submit manuscript

Abstract

Subclinical hypothyroidism is a condition characterized by increased levels of thyroid-stimulating hormone (TSH) associated with normal levels of free triiodothyronine (FT3) and free thyroxine (FT4). The exact prevalence of this condition in Italy is not known. The aim of this study was to assess the presence of subclinical hypothyroidism in 1001 subjects living in the Milan area (age 17–89) and apparently free from thyroid pathology. This sample which had applied to a large laboratory centre (Centro Diagnostico Italiano, Milano) for a routine check-up was seen from April to July 1996. A serum TSH assay was performed using a highly sensitive immunoenzymatic method, while an FT3 and FT4 assay was performed by means of a radioimmunologic method using commercial kits. The prevalence of subclinical hypothyroidism in the total population proved to be 4.7% (95% CI-Confidence Interval: 3.4–6.0). Sex stratification showed a prevalence of 6.1% in females and 3.4% in males. Prevalence in patients up to 65 was 4.2%. This value increased up to 8.0% in subjects over 65. By combining these variables, in females >65 prevalence increased to 11.3%. Overall, symptoms typical of overt hypothyroidism were found in 58.3% of patients suffering from subclinical hypothyroidism and in 39.9% of healthy subjects (p<0.02). The results of this study show that there is a significant presence (about 5%) of subclinical hypothyroidism in this population and that its frequency is more than doubled in women over 65. Early treatment might reduce the progression to overt hypothyroidism. The benefits of such a procedure were recently suggested by a decision making modelling approach applied to the Italian environment.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Similar content being viewed by others

References

  1. Brown C.A., Hennessey J.V. Clinical significance of mildly elevated thyrotropin levels with normal thyroxine levels. South Med. J. 1989, 82: 681–685.

    Article  CAS  PubMed  Google Scholar 

  2. Tunbridge W.M.G., Evered D.C., Hall R., Appleton D., Brewis M., Clark F., Evans J.G., Young E., Bird T., Smith P.A. The spectrum of thyroid disease in a community: the Whickham survey. Clin. Endocrinol. (Oxf) 1977, 7: 481–493.

    Article  CAS  Google Scholar 

  3. Bemben D.A., Hamm R.M., Morgan L., Winn P., Davis A., Barton E. Thyroid disease in the elderly. Part 2. Predictability of subclinical hypothyroidism. J. Fam. Pract. 1994, 38: 583–588.

    CAS  PubMed  Google Scholar 

  4. Rosenthal M.J., Hunt W.C., Garry P.J., Goodwin J.S. Thyroid failure in the elderly. Microsomal antibodies as discriminant for therapy. JAMA 1987, 258: 209–213.

    Article  CAS  PubMed  Google Scholar 

  5. Manciet G., Dartigues J.F., Decamps A., Barberger-Gateau P., Letenneur L., Latapie M.J., Latapie J.L. The PAQUID survey and correlates of subclinical hy- pothyroidism in elderly community residents in the southwest of France. Age Ageing 1995, 24: 235–241.

    Article  CAS  PubMed  Google Scholar 

  6. Schaaf L., Pohl T., Schmidt R., Vardali I., Teuber J., Schlote-Sauter B., Nowotny B., Schiebeler H., Zober A., Usadel K.H. Screening for thyroid disorders in a working population. Clin. Investig. 1993, 71: 126–131.

    Article  CAS  PubMed  Google Scholar 

  7. Hintze G., Burghardt U., Baumert J., Windeler J., Kobberling J. Prevalence of thyroid dysfunction in elderly subjects from the general population in an iodine deficiency area. Aging (Milano) 1991, 3: 325–331.

    CAS  Google Scholar 

  8. Brochmann H., Bjoro T., Gaarder P.I., Hanson F., Frey H.M. Prevalence of thyroid disorders in elderly subjects. A randomized study in a Norvegian rural community (Naeroy). Acta Endocrinol (Copenh.) 1988, 117: 7–12.

    CAS  Google Scholar 

  9. Okamura K., Nakashima T., Ueda K., Inoue K., Omae T., Fujishima M. Thyroid disorders in the general population of Hisayama Japan, with special reference to preva-lence and sex differences. Int. J. Epidemiol. 1987, 16: 545–549.

    Article  CAS  PubMed  Google Scholar 

  10. Muller G.M., Levitt N.S., Louw S.J. Thyroid disfunction in the elderly. S. Afr. Med. J. 1997, 87: 1119–1123.

    CAS  PubMed  Google Scholar 

  11. Jaeschke R., Guyatt G., Gerstein H., Patterson C., Molloy W., Cook D., Harper S., Griffith L., Carbotte K. Does treatment with L-thyroxine influence health status in middle-aged and older adults with subclinical hypothyroidism? J. Gen. Intern. Med. 1996, 11: 744–749.

    Article  CAS  PubMed  Google Scholar 

  12. Cooper D.S., Halpern R., Wood L.C., Levin A.A., Ridgway E.C. L-thyroxine therapy in subclinical hypothyroidism. Ann. Intern. Med. 1984, 101: 18–24.

    Article  CAS  PubMed  Google Scholar 

  13. Staub J.J., Althaus B.U., Engler H., Ryff A.S., Trabucco P., Marquardt K., Burckhardt D., Girard J., Weintraub B.D. Spectrum of subclinical and overt hypothyroidism: effect on thyrotropin, prolactin, and thyroid reserve, and metabolic impact on peripheral target tissues. Am. J. Med. 1992, 92: 631–642.

    Article  CAS  PubMed  Google Scholar 

  14. Miura S., Iitaka M., Yoshimura H., Kitahama S., Fukasawa N., Kawakami Y., Sakurai S., Urabe M., Sakatsume Y., Ito K. Disturbed lipid metabolism in patients with subclinical hypothyroidism: effect of L-thyroxine therapy. Int. Med. 1994, 33: 413–417.

    Article  CAS  Google Scholar 

  15. Tunbridge W.M., Brewis M., French J.M., Appleton D., Bird T., Clark F., Evered D.C., Grimley Evans J., Hall K., Smith P., Stephenson J., Young E. Natural history of autoimmune thyroiditis. Br. Med. J. 1981, 282: 258–262.

    Article  CAS  Google Scholar 

  16. Adlin V. Subclinical hypothyroidism: deciding when to treat. Am. Fam. Physician 1998, 57: 776–780.

    CAS  PubMed  Google Scholar 

  17. Cushing G.W. Subclinical hypothyroidism. Understanding is the key to decision making. Postgrad. Med. 1993, 94: 95–97.

    CAS  PubMed  Google Scholar 

  18. Monzani F., Caraccio N., Siciliano G., Manca L., Murri L., Ferrannini E. Clinical and biochemical features of muscle dys-function in subclinical hypothyroidism. J. Clin. Endocrinol. Metab. 1997, 82: 3315–3318.

    Article  CAS  PubMed  Google Scholar 

  19. Wiersinga W.M. Subclinical hypothyroidism and hyperthyroidism. I. Prevalence and clinical relevance. Neth. J. Med. 1995, 46: 197–204.

    Article  CAS  PubMed  Google Scholar 

  20. Miller M.J., Pan C., Barzel U.S. The prevalence of subclinical hypothyroidism in adults with low-normal blood thyroxine levels. N. Y. State J. Med. 1990, 90: 541–544.

    CAS  PubMed  Google Scholar 

  21. Woeber K.A. Subclinical thyroid disfunction. Arch. Intern. Med. 1997, 57: 1065–1068.

    Article  Google Scholar 

  22. U.S. Preventive Services Task Force. Guide to clinical preventive services: report of the U.S. Preventive Services Task Force. 2nd ed. Baltimore, Williams & Wilkins, 1996.

    Google Scholar 

  23. Helfand M., Crapo L.M. Screening for thyroid disease. Ann. Intern. Med. 1990, 112: 840–849.

    Article  CAS  PubMed  Google Scholar 

  24. Danese M.D., Powe N.R., Sawin C.T., Landenson P.W. Screening for mild thyroid failure at the periodic health examination: a decision and cost-effectiveness analysis. JAMA 1996, 276: 285–292.

    Article  CAS  PubMed  Google Scholar 

  25. Bona M., Santini F., Rivolta G., Grossi E., Grilli R. Cost effectiveness of screening for subclinical hypothy- roidism in the elderly. A decision-analytical model. Pharmacoeconomics 1998, 14: 209–216.

    Article  CAS  PubMed  Google Scholar 

Download references

Author information

Authors and Affiliations

Authors

Rights and permissions

Reprints and permissions

About this article

Cite this article

Rivolta, G., Cerutti, R., Colombo, R. et al. Prevalence of subclinical hypothyroidism in a population living in the Milan metropolitan area. J Endocrinol Invest 22, 693–697 (1999). https://doi.org/10.1007/BF03343631

Download citation

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1007/BF03343631

Key-words

Navigation