Endocrine Abstracts

Introduction: The association of systemic lupus erythematosus (SLE) and dysthyroidism has been reported by several studies in a wide range of variability but studies focused on the influence of hypothyroidism on classic manifestations of SLE are scarce. Our purpose was to evaluate the prevalence of thyroid diseases in a cohort of SLE patients and the relevance of hypothyroidism with clinical and analytical parameters related to lupus.

Methods/design: One hundred and three SLE patients underwent clinical examination and laboratory evaluation for thyroid hormones and the presence of antithyroid antibodies. Clinical manifestations and laboratory data of SLE between euthyroid and hypothyroid patients were compared.

Results: Twenty-four (23.3%) SLE patients had thyroid dysfunction. Prevalence of hypothyroidism was 17.5% (44.4% autoimmune in nature), subclinical hyperthyroidism 1.9% and euthyroid sick syndrome 3.9%. Patients with overt hypothyroidism, when compared with subclinical hypothyroidism, were significantly (P<0.03) younger and had a longer duration of SLE (35.4±9.5 vs 46.5±10.6 years and 14±4.2 vs 7.7±3.8 years respectively). Arthritis showed a significantly lower prevalence in patients with hypothyroidism when compared with euthyroid group (10.3 vs 30%; P=0.04) and its absence was more frequent in those with a longer duration of SLE. No difference in any analytical parameter between euthyroid and hypothyroid group of patients was found.

Conclusion: Hypothyroidism has little influence on classical manifestations of SLE. The lower frequency of arthritis in patients with hypothyroidism should be considered with caution since it was observed in subjects with longer SLE duration and received more number of treatments. Our data suggest that a most active search for thyroid dysfunction must be done in patients with an earlier onset of the disease.