Female sex hormones at the onset of systemic lupus erythematosus affect survival.

Female sex hormones affect susceptibility to systemic lupus erythematosus (SLE). To determine the effect of female sex hormones at onset of SLE on the survival of these patients, a retrospective survey was performed. The charts of 168 female SLE patients were evaluated to study the disease course, in particular the presence and kind of SLE criteria. Patients were classified as either belonging to the 'high female sex hormone at onset (HH)' or 'low female sex hormone at onset (LH)' group according to age at diagnosis. The statistics of the Dutch population, matched for age, were used to control for differences in life expectancy in these groups. A Cox regression model revealed that the relative mortality risk of HH patients vs HH controls was 4.2 times higher than the relative mortality risk of LH patients compared to LH controls. No differences in the frequency of SLE criteria between HH and LH patients were found that could explain the observed difference in mortality risk.