Endocrinology of aging
Philip E. Harris, Pierre-Marc G. Bouloux in Endocrinology in Clinical Practice, 2014
Subclinical hypothyroidism is by definition a laboratory diagnosis and is defined as an elevated TSH combined with a normal FT4 plus the absence of features of clinical hypothyroidism.20 The prevalence of hypothyroidism was found to vary significantly with age, gender, and race. The prevalence of subclinical hypothyroidism is about 4%–8.5%, depending on the type of population.9 Higher prevalence of subclinical hypothyroidism was observed in older adults compared with younger adults and was higher in women aged >60 years (~20%) compared with elderly men (8%).55 The prevalence is lower in blacks than in whites.9 The probability of progress from subclinical hypothyroidism to clinical hypothyroidism appears to be increased in individuals with higher levels of TSH, particularly true in females.56–58
Charlotte Naish (1908–1959)
Neil Metcalfe in 100 Notable Names from General Practice, 2018
To encourage preventative medicine and health education in the practice Naish started a mother’s club where she and other partners in the surgery gave talks. In addition to this she also held father’s clubs which discussed family problems. Through these clinics she was able to conduct numerous experiments using her patients. In 1954, an article was published in The Lancet, which detailed the positive results she noted on increasing breast milk production when giving small amounts of iodine to mothers who previously had been producing only small amounts of milk. Iodine is required by the body to make thyroxine in the thyroid gland and if low in amount can be one of the causes of an under-active thyroid condition also called hypothyroidism. Common symptoms of hypothyroidism include, depression, dry skin, loss of hair, tiredness and weight gain. These are symptoms, which Naish noticed in many of her multiparous patients, including herself. During a short space of time she was able to identify groups of women that were suffering from subclinical hypothyroidism, which was impacting on their ability to breastfeed their children. Although her findings were significant, she always highlighted that her results were not statistically valid. As her research and experiments continued, her research style became geared toward randomly controlled trails, which would validate her discoveries.
Thyroid Disorders
Keith Hopcroft in Instant Wisdom for GPs, 2017
Subclinical hypothyroidism is defined as a raised serum TSH and normal T4 and T3 levels. Treatment is generally advised in patients with positive thyroid antibodies (usually thyroid peroxidase antibodies [TPOAb]) or serum TSH >10 mU/L as progression to overt hypothyroidism is more likely in such individuals. Younger persons (<65 years old) with cardiovascular risk factors should also be treated, since studies have shown an association between subclinical hypothyroidism and cardiovascular mortality. It is also reasonable to treat those with goitre or symptoms suggesting hypothyroidism – and women who are pregnant or intending conception, because of the potential risk of adverse pregnancy outcomes. If treatment is not advised, monitoring of serum TSH should be carried out 6–12 monthly.
ABCG2 Polymorphism rs2231142 and hypothyroidism in metastatic renal cell carcinoma patients treated with sunitinib
Published in Acta Clinica Belgica, 2019
Emilie Werbrouck, Julie Bastin, Diether Lambrechts, Annelies Verbiest, Thomas Van Brussel, Evelyne Lerut, Jean-Pascal Machiels, Vincent Verschaeve, Vincent Richard, Philip R. Debruyne, Brigitte Decallonne, Patrick Schöffski, Oliver Bechter, Pascal Wolter, Benoit Beuselinck
Thyroid dysfunction is a known adverse event of VEGFR-TKIs. In the majority of cases, hypothyroidism is observed, but also thyrotoxicosis can occur [3,4]. In the phase III COMPARZ trial, comparing first-line sunitinib with pazopanib, clinical hypothyroidism was observed in 135 out of 548 patients treated with sunitinib (24%) [5]. Hypothyroidism has also been shown for other TKIs used to treat clear cell mRCC such as pazopanib (12% of patients in the COMPARZ trial) [5], axitinib (19% of patients in the axitinib pivotal phase III trial) [6], sorafenib (8%) [6] and cabozantinib (20%) [7]. However, an increase in TSH can be observed without T4/FT4-decrease, thus without the development of clinical hypothyroidism. This condition is called subclinical hypothyroidism. In smaller studies that focused on thyroid dysfunction during VEGFR-TKI treatment, higher incidences of TSH-increase were found. In a retrospective series of 66 RCC patients treated with sunitinib, 46 patients (70%) showed elevated TSH values associated with decreased T4-levels in only 15 patients (23%) [8]. In a prospective series of 59 patients with either mRCC or gastrointestinal stromal tumors treated with sunitinib, a similar proportion of patients (66%) displayed thyroid dysfunction, defined as TSH-increase and/or T4 or T3-decrease [3].
Fatigue and its management in cancer patients undergoing VEGFR-TKI therapy
Published in Expert Opinion on Drug Safety, 2022
Thyroid hormones promote metabolism, and hypothyroidism develops if the body fails to produce enough of these hormones for whatever reason. The main symptom of hypothyroidism is fatigue, and other symptoms include lethargy, edema, feeling cold, weight gain, and slow movements. Hypothyroidism is treated with the synthetic T4 thyroid hormone levothyroxine (e.g. Thyradin S, ASKA Pharmaceutical Co., Ltd.) taken in oral form [60,61]. When 25 colon cancer patients were treated with regorafenib, thyroid-stimulating hormone (TSH) levels increased in all patients after administration, and they were persistently elevated in 11 of these patients. When levothyroxine was administered to these 11 patients, TSH returned to the normal range, and fatigue improved, as assessed on a 5-point scale. Severity of fatigue was also found to correlate with TSH levels [62]. I would suggest regular TSH testing, but levothyroxine therapy is recommended when patients develop persistent serum TSH elevation ≥10 IU/L or patients have milder hypothyroidism (THS between 7 and 10 IU/L), associated with clinical signs and symptoms highly suggestive of thyroid failure.
Using the Biopsychosocial Approach to Identify Factors Associated with Major Depressive Disorder for Individuals with Hypothyroidism
Published in Issues in Mental Health Nursing, 2022
Kennedy S. Anderson, Krista J. Howard, Kelly B. Haskard-Zolnierek, Julia Pruin, Rebecca G. Deason
Hypothyroidism, or underactive thyroid, is described as a deficiency of thyroid hormones (American Thyroid Association, 2020). A diagnosis of hypothyroidism is made following a blood test to assess the function of thyroid stimulating hormone (TSH), and treatment typically consists of the thyroid hormone supplement thyroxine (T4) while some patients also are given the additional triiodothyronine (T3) supplement. Common physical symptoms of hypothyroidism include lethargy, sensitivity to cold, constipation, dry skin, weight gain, sexual dysfunction, and neck swelling (Ali et al., 2017; El Saide Sayyah et al., 2013). Hypothyroidism has also been implicated in changes in mood and cognition, such as poorer attention, memory, and executive function and increased rates of anxiety and depression (Samuels, 2014).
Related Knowledge Centers
- Bradycardia
- Cold Sensitivity
- Constipation
- Endocrine Disease
- Fatigue
- Thyroid Hormones
- Thyroid
- Depression
- Weight Gain
- Goitre