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Objective: The aim of the study was to assess the economic consequences of the early screening and management for overt hypothyrodism in elderly women suffering from hypercholesterolaemia., Methods: A cost analysis was performed using screening decision tree followed by a Markov model, targeted on an hypothetical cohort of elderly women (i.e. > or = 55 years of age) suffering from hypercholesterolaemia. Two arms were compared, "no diagnosis", patients being treated by lipid lowering drugs in the long run, "diagnosis", patients being screened for thyroid disturbance and proposed adequate correction by hormone treatment. Relevant clinical data introduced into the model were obtained from published data and from experts. At the end of the initial diagnostic, patients could enter three different health states: euthyroidism, subclinical hypothyroidism or overt hypothyroidism. During 30 years, patients were assumed to be seen each year by a general practitioner for clinical examination and cholesterol dosage, plus, according to the health state evolution, TSH and T4 screening. In the baseline analysis, euthyroidian patients who had a inexplicable degradation of hypercholesterolaemia control were tested for TSH and, if abnormal, T4 serum; for subclinical hypothyroidian patients, TSH and T4 were measured every year. The direct costs taken into account were concerning medical supervision, drug treatment and biologic exams. Costs were analysed from the societal perspective and were expressed in 1998 French Francs (FF) with an accounting rate of 5% by year. A sensitivity analysis was also performed., Results: The total cost at 30-year was equal to 25,006 F for "diagnosis" strategy, to 24,390 F for "no diagnosis" strategy. The incremental cost of the first strategy decreased according to the time horizon. It was 6.8% at 5-year and 2.5% at 30-year. Results were sensitive to variation in response rate of hypercholesterolaemic patients to hormone treatment of hypothyroidism (0.25 in base-case)., Conclusion: The investment cost in screening and treatment of hypercholesterolemic female patient aged 55 and more can be considered offset in the long run (30 years). Considering the other important outcomes in favour of hormonal drug treatment of hypothyroidism, such as enhancement of well-being, functional capacities and quality of life, the "diagnosis" strategy can be recommended in the ambulatory medical practice.

In contrast to the complications of hyperthyroidism, the bone lesions associated with hypothyroidism have not been extensively studied. A prospective study was conducted in 20 adults with protothyroid acquired hypothyroidism did not reveal any abnormalities in the parameters of phospho-calcium metabolism or the concentrations of PTH and the metabolites of vitamin D. The histomorphometric study of bone revealed hyperosteoidosis reflected by a considerable increase in the index of thickness of the osteoid, essentially affecting the relative osteoid volume. The surfaces of resorption and the bony trabecular volume were within normal limits and the rate of calcification was slightly decreased. The modifications of the histomorphometric investigation can be interpreted as a consequence of the slowing down of the basal osseous activity (BMR) due to thyroid hormone deprivation.

Although bone changes in hyperthyroidism are well known, they have been much less studied in hypothyroidism and we set out to establish whether they did occur in the latter condition. We present the results of a prospective study of 20 adult patients, with acquired primary hypothyroidism. No changes in urinary or blood calcium or phosphorus metabolism were observed and serum parathormone, 25-hydro, 125-dihydro and 24-25-dihydroxycholecalciferol concentrations were normal. Histological examination of iliac crest bone biopsy after double labelling with tetracycline showed normal bone trabeculation volume, surface of resorption and rates of calcification. However, the relative osteoid volume was increased and there was a much higher osteoid thickness index. These observations may be explained by a global decrease in the activation and activity of the multicellular units of bone remodeling due to the general slowing of cellular metabolism encountered in that condition.

The signs of Sjögren's syndrome were systematically researched in 36 patients with hypothyroidism (myxoedema with atrophic thyroiditis in 32 cases, Hashimoto's thyroiditis in 4). In a quarter of these patients were noted separately submaxillary glands and/or parotids enlarged, buccal and/or lacrymal sicca syndromes, and antisalivaryy ducts antibodies. The histologic analysis of minor salivar glands revealed foci of lymphocytes and plasmocytes (grades 3 and 4 of Chisholm's classification) in 6 subjects. Similarities between the Sjögren's syndrome and the autoimmune thyroiditis were specified; their association in the same patients might be explained considering the genetic predisposition to these affections.