Thyroid Function in Adults with Prader–Willi Syndrome; a Cohort Study and Literature Review

Abstract

Prader–Willi syndrome (PWS) is a complex genetic syndrome combining hypotonia, hyperphagia, a PWS-specific neurocognitive phenotype, and pituitary hormone deficiencies, including hypothyroidism. The low muscle mass associated with PWS causes a low energy expenditure due to a low basal metabolic rate. Combined with increased energy intake due to hyperphagia, this results in a high risk of obesity and associated cardiovascular disease. To reduce the high mortality in PWS (3% yearly), exercise is extremely important. As hypothyroidism can impair exercise tolerance, early detection is crucial. We performed a literature search for articles on hypothyroidism in PWS, measured thyroid hormone (TH) levels in 122 adults with PWS, and performed a medical file search for medication use. Hypothyroidism (low free thyroxin) was present in 17%, and often central in origin (80%). Triiodothyronine levels were lower in patients who used psychotropic drugs, while other TH levels were similar. One in six patients in our cohort of adults with PWS had hypothyroidism, which is more than in non-PWS adults (3%). We recommend yearly screening of free thyroxin and thyroid-stimulating hormone levels to avoid the negative effects of untreated hypothyroidism on basal metabolic rate, body mass index, and cardiovascular risk. Additionally, we recommend measuring TH concentrations 3–4 months after the start of growth hormone treatment.

Bone Health in Adults With Prader–Willi Syndrome: Clinical Recommendations Based on a Multicenter Cohort Study

“…Osteoporosis was more prevalent in males than in females, and this remained significant even after correction for age, height, weight, and genotype. In a previous study, males and females differed with regard to the use of psychotropic medication, which was slightly increased in males ( 85 ). As the use of some types of psychotropic medication is related to decreased BMD ( 86 , 87 ), this might partly explain this difference.…”

Health Problems in Adults with Prader–Willi Syndrome of Different Genetic Subtypes: Cohort Study, Meta-Analysis and Review of the Literature

“…Patients who had experienced at least one episode of psychotic behavior (diagnosed by a psychologist/psychiatrist) were considered as having a (history of) psychosis. Part of the clinical data of this patient group has been previously published in another context [ 22 , 23 , 24 , 25 , 26 , 27 ].…”

Prader–Willi Syndrome in Adults: An Update On Nutritional Treatment and Pharmacological Approach

“…In the latter case, it results in low or low-normal concentrations of thyroid-stimulating hormone (TSH) and low concentrations of free thyroxine. Therefore, early screening of TSH and free thyroxin concentrations is recommended, and hypothyroid patients are treated with levothyroxine at standard replacement doses [42]. Additionally, thyroid function should be monitored 3-4 months after the start of GH therapy since GH could be responsible of an increased conversion of T4 to T3 [43].…”