hypothyroidism

Narcolepsy

Nathan Hinkle — Fri, 11 Sep 2026 05:00:00 +0000

Date Added:

September 11, 2026

Journal/Publication:

JAMA

Publisher:

The American Medical Association

Publication Date:

September 9, 2026

Pages:

E1-E2

URL:

Narcolepsy

Type:

Meta-analyses, Reviews, and Guidelines

Format:

Article

DOI (1):

doi: 10.1001/jama.2026.14685

Keywords

MeSH

RPR Commentary: A concise review of what we currently understand about narcolepsy. James W. Mold, MD, MPH

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Narcolepsy is a chronic neurologic disorder that causes severe daytime sleepiness and impaired quality of life. Symptoms typically begin around age 10 to 20 years, yet diagnosis is often delayed for more than a decade.1 Narcolepsy is classified into narcolepsy type 1 (NT1; narcolepsy with cataplexy) and narcolepsy type 2 (NT2; narcolepsy without cataplexy), with estimated global prevalences of 19 and 23 per 100 000 persons, respectively.2

Author/s:

Kiran P. Maski, Thomas Scammell

What Is Hypothyroidism?

Megan George — Fri, 12 Dec 2025 20:50:46 +0000

Date Added:

December 12, 2025

Journal/Publication:

JAMA

Publication Date:

December 11, 2025

URL:

What Is Hypothyroidism?

Type:

Patient Education Materials

DOI (1):

10.1001/jama.2025.19536

Keywords

MeSH

Information for patients about hypothyroidism. James W. Mold, MD, MPH

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Hypothyroidism is a disease of thyroid hormone deficiency.

The most common cause of hypothyroidism worldwide is insufficient intake of iodine, a mineral found in iodized salt and some foods (such as seafood and dairy) that is needed for production of thyroid hormones. In the US and other high-income countries, the most common cause of hypothyroidism is an autoimmune condition called Hashimoto thyroiditis.1

Author/s:

Krista Roberts

Hypothyroidism: A Review

Megan George — Thu, 04 Sep 2025 20:17:56 +0000

Date Added:

September 4, 2025

Journal/Publication:

JAMA

Publication Date:

September 3, 2025

URL:

Hypothyroidism: A Review

Type:

Meta-analyses, Reviews, and Guidelines

Format:

Article

DOI (1):

10.1001/jama.2025.13559

Keywords

PMID (1):

40900603

MeSH

A review of what we currently understand about hypothyroidism. James W. Mold, MD, MPH

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Importance: Hypothyroidism is a disease of thyroid hormone deficiency. The prevalence ranges from 0.3% to 12% worldwide, depending on iodine intake, and it is more common in women and older adults. Untreated hypothyroidism can cause serious health complications such as heart failure and myxedema coma.

Observations: Hashimoto thyroiditis (an autoimmune disease) is the cause of primary hypothyroidism in up to 85% of patients with hypothyroidism living in areas with adequate nutritional iodine levels. The risk of developing hypothyroidism is associated with genetic factors (having a first-degree relative with hypothyroidism), environmental factors (iodine deficiency), undergoing neck surgery or receiving radiation therapy, pregnancy in the setting of underlying autoimmune thyroid disease, and with the use of certain medications (eg, immune checkpoint inhibitors and amiodarone). Patients with hypothyroidism may have nonspecific symptoms due to metabolic slowing, including fatigue (68%-83%), weight gain (24%-59%), cognitive issues (45%-48%) such as memory loss and difficulty concentrating, and menstrual irregularities (approximately 23%) such as oligomenorrhea and menorrhagia. Hypothyroidism can cause insulin resistance and hyperglycemia in patients with diabetes, increase the risk for cardiovascular events, such as heart failure, and negatively affect female reproductive health, causing disrupted ovulation, infertility, and increased risk of miscarriage. Untreated hypothyroidism may progress to severe hypothyroidism with decompensation (myxedema coma), which is a condition associated with hypothermia, hypotension, and altered mental status that requires treatment in an intensive care unit and has a mortality rate of up to 30%. Hypothyroidism is diagnosed based on biochemical testing; a high thyrotropin (TSH) level and a low free thyroxine (T4) level indicate overt primary hypothyroidism. Screening for hypothyroidism is not recommended for asymptomatic individuals. Targeted testing is recommended for patients who are considered high risk (eg, patients with type 1 diabetes). First-line treatment for hypothyroidism is synthetic levothyroxine to normalize thyrotropin levels. Initial dosages should be tailored to patient-specific factors. Lower starting doses should be used for older patients or those with atrial fibrillation and coronary artery disease. Thyrotropin monitoring should be performed 6 to 8 weeks after initiating levothyroxine treatment, or when changing the dose, and then annually once the thyrotropin level is at goal to avoid overtreatment or undertreatment, both of which are associated with cardiovascular health risks.

Conclusions and relevance: Hypothyroidism may be associated with fatigue, weight gain, memory loss, difficulty concentrating, cardiovascular disease such as heart failure, menstrual irregularities, infertility, and increased risk of miscarriage. Levothyroxine is the first-line treatment to normalize the thyrotropin level and improve clinical manifestations due to hypothyroidism.

Author/s:

Layal Chaker, Maria Papaleontiou

Subclinical thyroid dysfunction is associated with adverse prognosis in heart failure patients with reduced ejection fraction

Jeffrey Wilson — Wed, 01 May 2019 20:12:59 +0000

Date Added:

May 1, 2019

Journal/Publication:

BMC Cardiovascular Disorders

Publisher:

BioMed Central

Publication Date:

April 4, 2019

Issue:

Volume:

URL:

Subclinical thyroid dysfunction is associated with adverse prognosis in heart failure patients with reduced ejection fraction

Type:

Meta-analyses, Reviews, and Guidelines

Format:

Article

DOI (1):

10.1186/s12872-019-1055-x

Keywords

hypothyroidism

hyperthyroidism

subclinical hypothryroidism

subclinical hyperthyroidism

PMID (1):

30947691

MeSH

hyperthyroidism

hypothyroidism

thyroid diseases

The adverse impacts of “subclinical” hypo- and hyperthyroidism have been extensively studied. Few have been found. Subclinical hyperthyroidism is associated with incident atrial fibrillation. This meta-analysis concluded that both subclinical hypo- and hyperthyroidism are associated with increased all-cause mortality rates in patients with congestive heart failure. James W. Mold, MD, MPH

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BACKGROUND:

Subclinical thyroid dysfunction whose typical patterns include subclinical hypothyroidism and subclinical hyperthyroidism, has been indicated to be associated with an increased risk of heart failure (HF). However, the relationship between subclinical thyroid dysfunction and the clinical outcomes of HF patients is uncertain. This meta-analysis was conducted to assess the association between subclinical thyroid dysfunction and the clinical outcomes of HF patients.

METHODS:

Pubmed, Embase, Web of Science and Cochrane Central Register of Clinical Trials were searched for eligible studies published up to August 1, 2018 which reported the association between subclinical thyroid dysfunction and the clinical outcomes of HF patients. The pooled hazard ratio (HR) with the corresponding 95% confidence interval (CI) was used to assess the association.

RESULTS:

Fourteen studies met the eligibility criteria and a total of 21,221 patients with heart failure were included in the meta-analysis. Compared with HF patients with euthyroidism, the pooled HR of subclinical hypothyroidism for all-cause mortality was 1.45 (95% CI 1.26-1.67) in a randomized effects model with mild heterogeneity (I2 = 40.1, P = 0.073). The pooled HR of subclinical hypothyroidism for cardiac death and/or hospitalization was 1.33 (1.17-1.50) in a randomized effects model with moderate heterogeneity (I2 = 69.4, P < 0.001). Subclinical hyperthyroid can increase the risk of all-cause mortality without heterogeneity (HR 1.31, 95% CI 1.10-1.55, I2 = 25.5%, P = 0.225) but have no influence on the risk of cardiac death and/or hospitalization (HR 1.03, 95% CI 0.87-1.23, I2 = 0.0%, P = 0.958). These significant adverse associations were also retained in subgroup analysis. Sensitivity analysis demonstrated the stability of the results of our meta-analysis.

CONCLUSIONS:

Both subclinical hypothyroidism and subclinical hyperthyroidism are associated with adverse prognosis in patients with HF. Subclinical thyroid dysfunction may be a useful and promising predictor for the long-term prognosis in HF patients.

Author/s:

Yang, Guodong, Wang, Ya, Ma, Aiqun, Wang, Tingzhong