title: Raised serum TSH in morbid-obese and non-obese patients: effect on the circulating lipid profile.
abstract: Morbid obesity is associated with a high rate of raised serum TSH associated with normal free thyroid hormones. The body repercussions of this thyroid abnormality, suggesting subclinical hypothyroidism, are still debated. In particular, it is unclear whether the raised serum TSH of obesity results in changes of circulating lipids typically observed in hypothyroidism. Aim of this study was to evaluate the impact of a raised serum TSH on the lipid profile in morbid-obese and non-obese patients. Serum TSH, FT4, FT3, Tg-Ab, TPO-Ab and lipids were measured in 55 morbid-obese (BMI > 40 kg/m(2)) and 55 non-obese (BMI < 30 kg/m(2)) patients with a raised serum TSH. Despite similar serum levels of TSH, FT4 and FT3, morbid-obese patients displayed significantly lower mean levels of total cholesterol (200.8 ± 35.6 vs. 226.9 ± 41.4 mg/dl, p < 0.001) and a significantly lower prevalence of hypercholesterolemia (50.9 vs. 72.7 %, p < 0.01) when compared with non-obese patients. Morbid-obese patients also had lower mean serum HDL cholesterol and higher serum triglycerides. The impact of a raised serum TSH on the lipid profile differs in morbid-obese compared to non-obese patients, suggesting that obese patients might not be truly hypothyroid. Measuring total cholesterol could be a helpful tool for deciding whether a morbid-obese patient with a raised serum TSH should be given levothyroxine treatment.
authors.affiliation: Unit of Internal Medicine and Endocrinology, Fondazione Salvatore Maugeri I.R.C.C.S., Chair of Endocrinology, University of Pavia, Via S. Maugeri 10, 27100, Pavia, Italy.
authors.forename: Mario
authors.initials: M
authors.lastname: Rotondi
authors.forename: Paola
authors.initials: P
authors.lastname: Leporati
authors.forename: Maria Ileana
authors.initials: MI
authors.lastname: Rizza
authors.forename: Alessandra
authors.initials: A
authors.lastname: Clerici
authors.forename: Gloria
authors.initials: G
authors.lastname: Groppelli
authors.forename: Cristina
authors.initials: C
authors.lastname: Pallavicini
authors.forename: Antonella
authors.initials: A
authors.lastname: La Manna
authors.forename: Rodolfo
authors.initials: R
authors.lastname: Fonte
authors.forename: Flavia
authors.initials: F
authors.lastname: Magri
authors.forename: Bernadette
authors.initials: B
authors.lastname: Biondi
authors.forename: Luca
authors.initials: L
authors.lastname: Chiovato
mesh_terms: D000328:Adult; D002784:Cholesterol / Q000097:blood; D005260:Female; D006801:Humans; D015228:Hypertriglyceridemia / Q000097:blood / Q000150:complications / Q000453:epidemiology; D007037:Hypothyroidism / Q000097:blood / Q000150:complications / Q000453:epidemiology; D056865:Ideal Body Weight; D050356:Lipid Metabolism; D008055:Lipids / Q000097:blood*; D008297:Male; D008875:Middle Aged; D009767:Obesity, Morbid / Q000097:blood* / Q000150:complications / Q000453:epidemiology; D050177:Overweight / Q000097:blood / Q000150:complications / Q000453:epidemiology; D015995:Prevalence; D013972:Thyrotropin / Q000097:blood*
chemical_list: D008055:Lipids; D013972:Thyrotropin; D002784:Cholesterol