Relationship between the number and impact of stressful life events and the onset of Graves' disease and toxic nodular goitre

BACKGROUND In the last few decades, several studies have suggested a possib le association between Stressful Life Events (SLEs) and the onset of Graves ' Disease (GD). However, others have criticised this association and it has not yet been possible to prove it unequivocally. At present, we are not aw are of studies correlating SLE and non autoimmune thyrotoxicosis. OBJECTIVE To assess possible associations between SLEs, the onset of GD and the onset of non autoimmune thyrotoxicosis (toxic nodular goitre, TNG). DESIGN A case-control retrospective study. PATIENTS This study included 93 subjects, divided into three groups of 31 e ach: GD, TNG and control (CG). The GD and TNG patients had thyroid disease diagnosed within the last 12 months, with clinical and biochemical confirma tion. In the CG, psychopathological and endocrine disturbances had been rul ed out. All three groups consisted of nine males (29%) and 22 females (71%) . The mean age was 38.4 +/- 10.9 years in the GD group, 48.3 +/- 11.1 years in the TNG group and 41.1 +/- 11.8 years in the CG group. SLEs were evalua ted (number and impact) for the 12 months preceding the onset of symptoms o f thyroid disease. MEASUREMENTS SLE occurrences and their impact on each group of cases were m easured. To assess SLEs, we used the Life Experiences Survey (LES). Our sta tistical analysis included descriptive techniques and parametric and/or non parametric comparative tests. P < 0.01 was considered statistically signifi cant. Odds ratios were also calculated. RESULTS Patients with GD had a significantly greater number of SLEs compare d to the TNG group and the CG (P < 0.001). The number and impact of negativ e SLEs were significantly higher in GD compared to TNG and CG (P < 0.001). The difference between TNG and CG was not significant (P > 0.01). GD had a higher impact of positive SLEs than TNG (P = 0.004), and no significant dif ferences were found between the GD group and CG. Neutral SLEs were similar in the three groups. CONCLUSIONS These results suggest that SLEs are a precipitating factor of t he onset of GD. We also demonstrated that SLEs do not seem to have any conc lusive relationship with the onset of TNG.