NHANES III measured serum TSH, total serum T(4), antithyroperoxidase (TPOAb), and antithyroglobulin (TgAb) antibodies from a sample of 17,353 people aged > or =12 yr representing the geographic and ethnic distribution of the U.S. population. These data provide a reference for other studies of these analytes in the U.S. For the 16,533 people who did not report thyroid disease, goiter, or taking thyroid medications (disease-free population), we determined mean concentrations of TSH, T(4), TgAb, and TPOAb. A reference population of 13,344 people was selected from the disease-free population by excluding, in addition, those who were pregnant, taking androgens or estrogens, who had thyroid antibodies, or biochemical hypothyroidism or hyperthyroidism. The influence of demographics on TSH, T(4), and antibodies was examined. Hypothyroidism was found in 4.6% of the U.S. population (0.3% clinical and 4.3% subclinical) and hyperthyroidism in 1.3% (0.5% clinical and 0.7% subclinical). (Subclinical hypothyroidism is used in this paper to mean mild hypothyroidism, the term now preferred by the American Thyroid Association for the laboratory findings described.) For the disease-free population, mean serum TSH was 1.50 (95% confidence interval, 1.46-1.54) mIU/liter, was higher in females than males, and higher in white non-Hispanics (whites) [1.57 (1.52-1.62) mIU/liter] than black non-Hispanics (blacks) [1.18 (1.14-1.21) mIU/liter] (P < 0.001) or Mexican Americans [1.43 (1.40-1.46) mIU/liter] (P < 0.001). TgAb were positive in 10.4 +/- 0.5% and TPOAb, in 11.3 +/- 0.4%; positive antibodies were more prevalent in women than men, increased with age, and TPOAb were less prevalent in blacks (4.5 +/- 0.3%) than in whites (12.3 +/- 0.5%) (P < 0.001). TPOAb were significantly associated with hypo or hyperthyroidism, but TgAb were not. Using the reference population, geometric mean TSH was 1.40 +/- 0.02 mIU/liter and increased with age, and was significantly lower in blacks (1.18 +/- 0.02 mIU/liter) than whites (1.45 +/- 0.02 mIU/liter) (P < 0.001) and Mexican Americans (1.37 +/- 0.02 mIU/liter) (P < 0.001). Arithmetic mean total T(4) was 112.3 +/- 0.7 nmol/liter in the disease-free population and was consistently higher among Mexican Americans in all populations. In the reference population, mean total T(4) in Mexican Americans was (116.3 +/- 0.7 nmol/liter), significantly higher than whites (110.0 +/- 0.8 nmol/liter) or blacks (109.4 +/- 0.8 nmol/liter) (P < 0.0001). The difference persisted in all age groups. In summary, TSH and the prevalence of antithyroid antibodies are greater in females, increase with age, and are greater in whites and Mexican Americans than in blacks. TgAb alone in the absence of TPOAb is not significantly associated with thyroid disease. The lower prevalence of thyroid antibodies and lower TSH concentrations in blacks need more research to relate these findings to clinical status. A large proportion of the U.S. population unknowingly have laboratory evidence of thyroid disease, which supports the usefulness of screening for early detection.

/pdf/serum-tsh-t4-and-thyroid-antibodies-in-the-united-states-guay38noxx.pdf

Serum TSH, T4, and Thyroid Antibodies in the United States Population (1988 to 1994): National Health and Nutrition Examination Survey (NHANES III)

ContextPatients with serum thyroid-stimulating hormone (TSH) levels outside
the reference range and levels of free thyroxine (FT4) and triiodothyronine
(T3) within the reference range are common in clinical practice.
The necessity for further evaluation, possible treatment, and the urgency
of treatment have not been clearly established.ObjectivesTo define subclinical thyroid disease, review its epidemiology, recommend
an appropriate evaluation, explore the risks and benefits of treatment and
consequences of nontreatment, and determine whether population-based screening
is warranted.Data SourcesMEDLINE, EMBASE, Biosis, the Agency for Healthcare Research and Quality,
National Guideline Clearing House, the Cochrane Database of Systematic Reviews
and Controlled Trials Register, and several National Health Services (UK)
databases were searched for articles on subclinical thyroid disease published
between 1995 and 2002. Articles published before 1995 were recommended by
expert consultants.Study Selection and Data ExtractionA total of 195 English-language or translated papers were reviewed.
Editorials, individual case studies, studies enrolling fewer than 10 patients,
and nonsystematic reviews were excluded. Information related to authorship,
year of publication, number of subjects, study design, and results were extracted
and formed the basis for an evidence report, consisting of tables and summaries
of each subject area.Data SynthesisThe strength of the evidence that untreated subclinical thyroid disease
is associated with clinical symptoms and adverse clinical outcomes was assessed
and recommendations for clinical practice developed. Data relating the progression
of subclinical to overt hypothyroidism were rated as good, but data relating
treatment to prevention of progression were inadequate to determine a treatment
benefit. Data relating a serum TSH level higher than 10 mIU/L to elevations
in serum cholesterol were rated as fair but data relating to benefits of treatment
were rated as insufficient. All other associations of symptoms and benefit
of treatment were rated as insufficient or absent. Data relating a serum TSH
concentration lower than 0.1 mIU/L to the presence of atrial fibrillation
and progression to overt hyperthyroidism were rated as good, but no data supported
treatment to prevent these outcomes. Data relating restoration of the TSH
level to within the reference range with improvements in bone mineral density
were rated as fair. Data addressing all other associations of subclinical
hyperthyroid disease and adverse clinical outcomes or treatment benefits were
rated as insufficient or absent. Subclinical hypothyroid disease in pregnancy
is a special case and aggressive case finding and treatment in pregnant women
can be justified.ConclusionsData supporting associations of subclinical thyroid disease with symptoms
or adverse clinical outcomes or benefits of treatment are few. The consequences
of subclinical thyroid disease (serum TSH 0.1-0.45 mIU/L or 4.5-10.0 mIU/L)
are minimal and we recommend against routine treatment of patients with TSH
levels in these ranges. There is insufficient evidence to support population-based
screening. Aggressive case finding is appropriate in pregnant women, women
older than 60 years, and others at high risk for thyroid dysfunction.

https://jamanetwork.com/journals/jama/articlepdf/197994/JSR30016.pdf

Subclinical thyroid disease: scientific review and guidelines for diagnosis and management.

Epidemiology and Estimated Population Burden of Selected Autoimmune Diseases in the United States

CONTEXT\nHypertension is associated with a significantly increased risk of morbidity and mortality. Only diuretics and beta-blockers have been shown to reduce this risk in long-term clinical trials. Whether newer antihypertensive agents reduce the incidence of cardiovascular disease (CVD) is unknown.\n\n\nOBJECTIVE\nTo compare the effect of doxazosin, an alpha-blocker, with chlorthalidone, a diuretic, on incidence of CVD in patients with hypertension as part of a study of 4 types of antihypertensive drugs: chlorthalidone, doxazosin, amlodipine, and lisinopril.\n\n\nDESIGN\nRandomized, double-blind, active-controlled clinical trial, the Antihypertensive and Lipid-Lowering Treatment to Prevent Heart Attack Trial, initiated in February 1994. In January 2000, after an interim analysis, an independent data review committee recommended discontinuing the doxazosin treatment arm based on comparisons with chlorthalidone. Therefore, outcomes data presented herein reflect follow-up through December 1999.\n\n\nSETTING\nA total of 625 centers in the United States and Canada.\n\n\nPARTICIPANTS\nA total of 24,335 patients (aged > or = 55 years) with hypertension and at least 1 other coronary heart disease (CHD) risk factor who received either doxazosin or chlorthalidone.\n\n\nINTERVENTIONS\nParticipants were randomly assigned to receive chlorthalidone, 12.5 to 25 mg/d (n=15,268), or doxazosin, 2 to 8 mg/d (n=9067), for a planned follow-up of 4 to 8 years.\n\n\nMAIN OUTCOME MEASURES\nThe primary outcome measure was fatal CHD or nonfatal myocardial infarction (MI), analyzed by intent to treat; secondary outcome measures included all-cause mortality, stroke, and combined CVD (CHD death, nonfatal MI, stroke, angina, coronary revascularization, congestive heart failure [CHF], and peripheral arterial disease); compared by the chlorthalidone group vs the doxazosin group.\n\n\nRESULTS\nMedian follow-up was 3.3 years. A total of 365 patients in the doxazosin group and 608 in the chlorthalidone group had fatal CHD or nonfatal MI, with no difference in risk between the groups (relative risk [RR], 1.03; 95% confidence interval [CI], 0.90-1.17; P=.71). Total mortality did not differ between the doxazosin and chlorthalidone arms (4-year rates, 9.62% and 9.08%, respectively; RR, 1.03; 95% CI, 0.90-1.15; P=.56.) The doxazosin arm, compared with the chlorthalidone arm, had a higher risk of stroke (RR, 1.19; 95% CI, 1.01-1.40; P=.04) and combined CVD (4-year rates, 25.45% vs 21.76%; RR, 1.25; 95% CI, 1.17-1.33; P<.001). Considered separately, CHF risk was doubled (4-year rates, 8.13% vs 4.45%; RR, 2.04; 95% CI, 1.79-2.32; P<.001); RRs for angina, coronary revascularization, and peripheral arterial disease were 1.16 (P<.001), 1.15 (P=.05), and 1.07 (P=.50), respectively.\n\n\nCONCLUSION\nOur data indicate that compared with doxazosin, chlorthalidone yields essentially equal risk of CHD death/nonfatal MI but significantly reduces the risk of combined CVD events, particularly CHF, in high-risk hypertensive patients.

Major cardiovascular events in hypertensive patients randomized to doxazosin vs chlorthalidone: The antihypertensive and lipid-lowering treatment to prevent heart attack trial (ALLHAT)

https://endoinfo.ru/guidelines/ata_hypothyroidism_adults.pdf

Clinical Practice Guidelines for Hypothyroidism in Adults: Cosponsored by the American Association of Clinical Endocrinologists and the American Thyroid Association

Summary
BACKGROUND AND OBJECTIVE The original Whlckham Survey documented the prevalence of thyroid disorders in a randomly selected sample of 2779 adults which matched the population of Great Britain in age, sex and social class. The aim of the twenty-year follow-up survey was to determine the Incidence and natural history of thyroid disease in this cohort.

DESIGN, PATIENTS AND MEASUREMENTS Subjects were traced at follow-up via the Electoral Register, General Practice registers, Gateshead Family Health Services Authority register and Office of Population Censuses and Surveys. Eight hundred and twenty-five subjects (30% of the sample) had died and, In addition to death certificates, two-thirds had Information from either hospital/General Practitioner notes or post-mortem reports to document morbidity prior to death. Of the 1877 known survivors, 96% participated in the follow-up study and 91 % were tested for clinical, biochemical and Immunological evidence of thyroid dysfunction.

RESULTS Outcomes in terms of morbidity and mortality were determined for over 97% of the original sample. The mean Incidence (with 95% confidence Intervals) of spontaneous hypothyroidism in women was 3.5/1000 survivors/year (2.8-4.5) rising to 4.1/1000 survivors/year (3.3-5.0) for all causes of hypothyroidism and in men was 0.6/1000 survivors/year (0.3-1.2). The mean incidence of hyperthyroidism In women was 0.8/1000 survivors/year (0.5.1.4) and was negligible in men. Similar incidence rates were calculated for the deceased subjects. An estimate of the probability of the development of hypothyroidism and hyperthyroidism at a particular time, i.e. the hazard rate, showed an Increase with age In hypothyroidism but no age relation in hyperthyroidism.

The frequency of goitre decreased with age with 10% of women and 2% of men having a goitre at follow-up, as compared to 23% and 5% in the same subjects respectively at the first survey. The presence of a goitre at either survey was not associated with any clinical or biochemical evidence of thyroid dysfunction. In women, an association was found between the development of a goitre and thyroid-antibody status at follow-up, but not initially.

The risk of having developed hypothyroidism at follow-up was examined with respect to risk factors Identified at first survey. The odds ratios (with 95% confidence Intervals) of developing hypothyroidism with (a) raised serum TSH alone were 8 (3-20) for women and 44 (19-104) for men; (b) positive anti-thyroid antibodies alone were 8 (5-15) for women and 25 (10-63) for men; (c) both raised serum TSH and positive anti-thyroid antibodies were 38 (22-65) for women and 173 (81-370) for men. A loglt model Indicated that Increasing values of serum TSH above 2mU/l at first survey Increased the probability of developing hypothyroidism which was further Increased in the presence of anti-thyroid antibodies. Neither a positive family history of any form of thyroid disease nor parity of women at first survey was associated with Increased risk of developing hypothyroidism. Fasting cholesterol and triglyceride levels at first survey when corrected for age showed no association with the development of hypothyroidism In women.

CONCLUSIONS This historical cohort study has provided Incidence data for thyroid disease over a twenty-year period for a representative cross-sectional sample of the population, and has allowed the determination of the importance of prognostic risk factors for thyroid disease Identified twenty years earlier.

/pdf/the-incidence-of-thyroid-disorders-in-the-community-a-twenty-26md1r21cb.pdf

W. M. G. Tunbrldge

Papers

The incidence of thyroid disorders in the community: a twenty-year follow-up of the Whickham Survey