Endocrine Abstracts (2006) 11 P877

Age and gender differences and phenotypes of patients with autoimmune thyroid disease – The UK AITD consortium

JD Carr-Smith1, N Manji1, K Boelaert1, A Allahabadia2, M Armitage4, J Lazarus5, S Pearce6, B Viadja3, SC Gough1 & JA Franklyn1

1University of Birmingham, Birmingham, United Kingdom; 2Sheffield University, Sheffield, United Kingdom; 3Peninsula Medical School, Universities of Exeter and Plymouth, Exeter, United Kingdom; 4Royal Bournemouth Hospital, Bournemouth, United Kingdom; 5University of Wales College of Medicine, Cardiff, United Kingdom; 6Newcastle University, Newcastle, United Kingdom.

The cohort comprised 2296 patients with Graves’ disease (GD) (1920 females, 376 males) and 361 with Hashimoto’s thyroiditis (HT) (313 females, 48 males) recruited using standard diagnostic criteria for investigation of genetic susceptibility to AITD. We investigated variation in disease phenotype with age and gender, examining factors including biochemical severity, presence of goitre and presence of thyroid eye disease (TED) classified by NOSPECS score.

The median age at diagnosis was lower in GD females (40y [IQR 31–51]) than males (44.5[33–56], P<0.001), with a similar age difference for HT (females 41.0 [31–52], males 49.0[37.5–58], P=0.01). Biochemical severity (presentation serum fT4) was higher in both male and female subjects with GD and goitre compared with those without thyroid enlargement (females with goitre: median fT4 45.0 pmol/l [30.4–66.6] vs 36.0[25–52], P<0.001; males with goitre: fT4 44.9[33–68.1] vs 36.0[26–55], P=0.009), but there was no difference in severity of hypothyroidism (presentation serum TSH) in those with HT divided according to presence or absence of goitre (females with goitre: TSH 12.3 mIU/l [7.3–50] vs 11.5[7.2–25.3], P=0.178; males with goitre: 20.5[17.0–38.0] vs 19.4[9.6–100], P=0.99). Amongst those with GD, males were over-represented in those with severe TED (NOSPECS score 4 or more) (males 116 of 365, 31.8% vs females 410 of 1861, 22.0%, P<0.001) and the median age of males with severe TED was higher than females with severe TED (52.0[40–59], vs 43.0[32–54], P<0.001). There was also a higher prevalence of severe TED in those presenting at older age with GD (males <40y 19.8% vs males >40y 38.8%; females <40y 18.2% vs females >40y 24.7%, P=0.003). AITDs are diagnosed older in males than females. Males with GD have biochemically more severe disease, and more severe TED. Gender thus has a major impact on disease phenotype in AITD with potential consequences for therapeutic management.