Introduction: The adult Turner Syndrome (TS) clinic at UCLH has collected data on over 800 women, attending for up to 20 years comprising over 8000 clinic visits. Data from this cohort forms the Turner Life Course Project. This large dataset allows analysis of pathogenesis of common chronic conditions including diabetes mellitus (DM) and hypothyroidism. There is some debate about the classification of DM associated with TS, with an over representation of up to 11-fold of type 1 and 4-fold of type 2 forms. Diabetes related autoantibodies and insulin resistance are not prominent in adults with TS and diabetes. In this study we present an analysis of the factors associated with DM in adult women with TS.
Methods: We performed a retrospective analysis of 565 women with TS in whom DM status was confirmed. TS health surveillance parameters were compared in those with DM to those without. Factors affecting DM risk included karyotype, age, BMI, hypothyroidism, streatohepatitis and congenital heart disease. Binary regression analysis was performed in order to assess interaction between variables.
Results: Diabetes had been diagnosed in 46/565 (8%) of women with TS in whom the mean age was 43.7 years compared to 32.9 years without DM. DM was associated with older age, a higher BMI, raised liver enzymes and hypothyroidism compared to non-diabetics (P=<0.05). Hypothyroidism was present in 11.7% of women with TS and DM compared to 4.7% of those without (P=0.01). Hypothyroidsim remained an independent association, when controlled for age and BMI and could not be accounted for by differences in TSH concentrations.
Conclusions: The association between hypothyroidism and DM in women with TS raises the possibility that autoimmunity is of greater importance in the pathogenesis of DM than had previously been recognised, in spite of lack of DM related autoantibodies previously reported.