Minimally symptomatic (subclinical) hypothyroidism

Alejandro R Ayala, Leonard Wartofsky

Research output: Contribution to journalArticle

24 Citations (Scopus)

Abstract

Subclinical hypothyroidism is defined by the presence of mild thyrotropin (TSH) elevation but normal blood free thyroxine and free triiodothyronine levels. The adjective 'subclinical' seems awkward, if not inaccurate, given that it is arguable whether these patients are truly asymptomatic and in view of the support in the literature for a salutary effect of thyroid hormone therapy. In view of this and the evidence that the majority of such patients eventually evolve into overt thyroid failure, we propose that a more appropriate term is minimally symptomatic hypothyroidism (MSH). The most common causes of this syndrome are the same as those for overt hypothyroidism and include chronic autoimmune (Hashimoto's) thyroiditis, thyroid ablation with radioactive iodine, antithyroidal drugs, and thyroidectomy. Ideally, the diagnosis is best considered in an outpatient setting, because confounding factors in hospitalized patients, such as severe systemic illness and medications, can cause misleadingly elevated TSH levels. Although target organ dysfunction is not as evident as in overt hypothyroidism, well-designed studies have reported subtle elevations in atherogenic lipoprotein fractions, suboptimal left ventricular function, and discrete neuropsychiatric abnormalities. In minimally symptomatic patients, it is important to reconcile optimal medical practice with the increasing demands of the current health care system for a judicious and cost-effective approach to diagnosis and management. An initial clinical assessment for MSH could focus on identifying individuals vulnerable to thyroid disorders, such as patients with a family or past medical history of thyroid disease, patients with a goiter or history of recent pregnancy, patients taking medications that could interfere with thyroid function, or patients with hypercholesterolemia. TSH should be measured in all patients at risk, and measurement of thyroid antibody titers may be useful insofar as they confirm autoimmune thyroid disease and predict progression to frank hypothyroidism, especially in the geriatric population. We believe that there is reason to expect benefits from initiation of replacement therapy with levothyroxine, including relief of symptoms, improvement in lipid profiles and cardiovascular risk, and prevention of progression to overt hypothyroidism. Levothyroxine is given in the usual recommended doses, with an ultimate target dose of approximately 1.7 μg/kg, titrated accordingly to maintain serum TSH within the normal (measurable) range. Although still controversial, one recent article suggests that screening women older than age 35 every 5 years for MSH may be as cost-effective as screening for breast cancer or hypertension.

Original languageEnglish
Pages (from-to)44-50
Number of pages7
JournalEndocrinologist
Volume7
Issue number1
StatePublished - Jan 1 1997
Externally publishedYes

Fingerprint

Hypothyroidism
Thyroid Gland
Thyroxine
Thyroid Diseases
Autoimmune Thyroiditis
Costs and Cost Analysis
Reproductive History
Hashimoto Disease
Thyroidectomy
Goiter
Triiodothyronine
Thyrotropin
Hypercholesterolemia
Thyroid Hormones
Left Ventricular Function
Iodine
Geriatrics
Autoimmune Diseases
Lipoproteins
Disease Progression

ASJC Scopus subject areas

  • Endocrinology

Cite this

Minimally symptomatic (subclinical) hypothyroidism. / Ayala, Alejandro R; Wartofsky, Leonard.

In: Endocrinologist, Vol. 7, No. 1, 01.01.1997, p. 44-50.

Research output: Contribution to journalArticle

Ayala, AR & Wartofsky, L 1997, 'Minimally symptomatic (subclinical) hypothyroidism', Endocrinologist, vol. 7, no. 1, pp. 44-50.
Ayala, Alejandro R ; Wartofsky, Leonard. / Minimally symptomatic (subclinical) hypothyroidism. In: Endocrinologist. 1997 ; Vol. 7, No. 1. pp. 44-50.
@article{d761370c3ca54bf9a75abd96e35ae20c,
title = "Minimally symptomatic (subclinical) hypothyroidism",
abstract = "Subclinical hypothyroidism is defined by the presence of mild thyrotropin (TSH) elevation but normal blood free thyroxine and free triiodothyronine levels. The adjective 'subclinical' seems awkward, if not inaccurate, given that it is arguable whether these patients are truly asymptomatic and in view of the support in the literature for a salutary effect of thyroid hormone therapy. In view of this and the evidence that the majority of such patients eventually evolve into overt thyroid failure, we propose that a more appropriate term is minimally symptomatic hypothyroidism (MSH). The most common causes of this syndrome are the same as those for overt hypothyroidism and include chronic autoimmune (Hashimoto's) thyroiditis, thyroid ablation with radioactive iodine, antithyroidal drugs, and thyroidectomy. Ideally, the diagnosis is best considered in an outpatient setting, because confounding factors in hospitalized patients, such as severe systemic illness and medications, can cause misleadingly elevated TSH levels. Although target organ dysfunction is not as evident as in overt hypothyroidism, well-designed studies have reported subtle elevations in atherogenic lipoprotein fractions, suboptimal left ventricular function, and discrete neuropsychiatric abnormalities. In minimally symptomatic patients, it is important to reconcile optimal medical practice with the increasing demands of the current health care system for a judicious and cost-effective approach to diagnosis and management. An initial clinical assessment for MSH could focus on identifying individuals vulnerable to thyroid disorders, such as patients with a family or past medical history of thyroid disease, patients with a goiter or history of recent pregnancy, patients taking medications that could interfere with thyroid function, or patients with hypercholesterolemia. TSH should be measured in all patients at risk, and measurement of thyroid antibody titers may be useful insofar as they confirm autoimmune thyroid disease and predict progression to frank hypothyroidism, especially in the geriatric population. We believe that there is reason to expect benefits from initiation of replacement therapy with levothyroxine, including relief of symptoms, improvement in lipid profiles and cardiovascular risk, and prevention of progression to overt hypothyroidism. Levothyroxine is given in the usual recommended doses, with an ultimate target dose of approximately 1.7 μg/kg, titrated accordingly to maintain serum TSH within the normal (measurable) range. Although still controversial, one recent article suggests that screening women older than age 35 every 5 years for MSH may be as cost-effective as screening for breast cancer or hypertension.",
author = "Ayala, {Alejandro R} and Leonard Wartofsky",
year = "1997",
month = "1",
day = "1",
language = "English",
volume = "7",
pages = "44--50",
journal = "Endocrinologist",
issn = "1051-2144",
publisher = "Lippincott Williams and Wilkins",
number = "1",

}

TY - JOUR

T1 - Minimally symptomatic (subclinical) hypothyroidism

AU - Ayala, Alejandro R

AU - Wartofsky, Leonard

PY - 1997/1/1

Y1 - 1997/1/1

N2 - Subclinical hypothyroidism is defined by the presence of mild thyrotropin (TSH) elevation but normal blood free thyroxine and free triiodothyronine levels. The adjective 'subclinical' seems awkward, if not inaccurate, given that it is arguable whether these patients are truly asymptomatic and in view of the support in the literature for a salutary effect of thyroid hormone therapy. In view of this and the evidence that the majority of such patients eventually evolve into overt thyroid failure, we propose that a more appropriate term is minimally symptomatic hypothyroidism (MSH). The most common causes of this syndrome are the same as those for overt hypothyroidism and include chronic autoimmune (Hashimoto's) thyroiditis, thyroid ablation with radioactive iodine, antithyroidal drugs, and thyroidectomy. Ideally, the diagnosis is best considered in an outpatient setting, because confounding factors in hospitalized patients, such as severe systemic illness and medications, can cause misleadingly elevated TSH levels. Although target organ dysfunction is not as evident as in overt hypothyroidism, well-designed studies have reported subtle elevations in atherogenic lipoprotein fractions, suboptimal left ventricular function, and discrete neuropsychiatric abnormalities. In minimally symptomatic patients, it is important to reconcile optimal medical practice with the increasing demands of the current health care system for a judicious and cost-effective approach to diagnosis and management. An initial clinical assessment for MSH could focus on identifying individuals vulnerable to thyroid disorders, such as patients with a family or past medical history of thyroid disease, patients with a goiter or history of recent pregnancy, patients taking medications that could interfere with thyroid function, or patients with hypercholesterolemia. TSH should be measured in all patients at risk, and measurement of thyroid antibody titers may be useful insofar as they confirm autoimmune thyroid disease and predict progression to frank hypothyroidism, especially in the geriatric population. We believe that there is reason to expect benefits from initiation of replacement therapy with levothyroxine, including relief of symptoms, improvement in lipid profiles and cardiovascular risk, and prevention of progression to overt hypothyroidism. Levothyroxine is given in the usual recommended doses, with an ultimate target dose of approximately 1.7 μg/kg, titrated accordingly to maintain serum TSH within the normal (measurable) range. Although still controversial, one recent article suggests that screening women older than age 35 every 5 years for MSH may be as cost-effective as screening for breast cancer or hypertension.

AB - Subclinical hypothyroidism is defined by the presence of mild thyrotropin (TSH) elevation but normal blood free thyroxine and free triiodothyronine levels. The adjective 'subclinical' seems awkward, if not inaccurate, given that it is arguable whether these patients are truly asymptomatic and in view of the support in the literature for a salutary effect of thyroid hormone therapy. In view of this and the evidence that the majority of such patients eventually evolve into overt thyroid failure, we propose that a more appropriate term is minimally symptomatic hypothyroidism (MSH). The most common causes of this syndrome are the same as those for overt hypothyroidism and include chronic autoimmune (Hashimoto's) thyroiditis, thyroid ablation with radioactive iodine, antithyroidal drugs, and thyroidectomy. Ideally, the diagnosis is best considered in an outpatient setting, because confounding factors in hospitalized patients, such as severe systemic illness and medications, can cause misleadingly elevated TSH levels. Although target organ dysfunction is not as evident as in overt hypothyroidism, well-designed studies have reported subtle elevations in atherogenic lipoprotein fractions, suboptimal left ventricular function, and discrete neuropsychiatric abnormalities. In minimally symptomatic patients, it is important to reconcile optimal medical practice with the increasing demands of the current health care system for a judicious and cost-effective approach to diagnosis and management. An initial clinical assessment for MSH could focus on identifying individuals vulnerable to thyroid disorders, such as patients with a family or past medical history of thyroid disease, patients with a goiter or history of recent pregnancy, patients taking medications that could interfere with thyroid function, or patients with hypercholesterolemia. TSH should be measured in all patients at risk, and measurement of thyroid antibody titers may be useful insofar as they confirm autoimmune thyroid disease and predict progression to frank hypothyroidism, especially in the geriatric population. We believe that there is reason to expect benefits from initiation of replacement therapy with levothyroxine, including relief of symptoms, improvement in lipid profiles and cardiovascular risk, and prevention of progression to overt hypothyroidism. Levothyroxine is given in the usual recommended doses, with an ultimate target dose of approximately 1.7 μg/kg, titrated accordingly to maintain serum TSH within the normal (measurable) range. Although still controversial, one recent article suggests that screening women older than age 35 every 5 years for MSH may be as cost-effective as screening for breast cancer or hypertension.

UR - http://www.scopus.com/inward/record.url?scp=0031049856&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0031049856&partnerID=8YFLogxK

M3 - Article

AN - SCOPUS:0031049856

VL - 7

SP - 44

EP - 50

JO - Endocrinologist

JF - Endocrinologist

SN - 1051-2144

IS - 1

ER -