[Subclinical hypothyroidism and quality of life of women aged 50 or more with hypercholesterolemia: results of the HYOGA study]

Abstract

Aim: Subclinical hypothyroidism (SCHT) is defined by the combination of an increased TSH level and a normal free thyroxin concentration. The aim of this survey is the description of the prevalence, the symptoms and the quality of life in SCHT diagnosed in a group of hypercholesterolemic women.

Methods: A total of 1610 female patients aged 50 or more with hypercholesterolemia (total cholesterol between 240 and 400mg/dl, receiving or not a lipid-lowering treatment) were enrolled by 347 general practitioners (GPs). A clinical form including symptoms, clinical history, and treatments was completed by GPs while a SF-36 QOL form was filled up by the patients. Further GPs' prescriptions for tests and treatments were also recorded.

Results: Full data leading to subclinical hypothyroidism are available in 721 patients (44.8%) who were selected into the study. Among these patients, the prevalence of SCHT (SCHT+) is 16.6% (120 patients) and 76.3% of the patients have at least one symptom. Most frequent symptoms are physical and intellectual asthenia, muscular weakness, and sensitivity to cold but those symptoms are present in patients without SCHT (SCHT-) too and there is no significant difference between the two groups. TSH level was 4 to 10 mUI/l in 90% of SCHT+ patients. 38.6% of hypercholesterolemic SCHT+ patients never had any TSH measurement. QOL is affected in SCHT+ compared to SCHT- patients with a significantly decreased mental summary score of 36.21+/-9.4 versus 39.4+/-12.18 (p<0.006). QOL (mental health score) is significantly lower when TSH value raised from a 2.4-4 range up to a 4-10 mUI/L range.

Conclusions: SCHT is frequent in a population of hypercholesterolemic female patients aged 50 or more. In the presence of suggestive symptoms, screening is important especially as QOL is affected even when TSH is < 10 mUI/L. It remains to show with controlled prospective studies whether thyroxin supplementation can improve symptoms and QOL.