Floortje Mols

Context Between 10% and 15% of people with hypothyroidism experience persistent symptoms, despite achieving biochemical euthyroidism. The underlying causes are unclear. Type D personality (a vulnerability factor for general psychological distress) is associated with poor health status and symptom burden but has not been studied in people with hypothyroidism. Objective To investigate type D personality in hypothyroidism and explore associations with other characteristics and patient-reported outcomes. Design Multinational, cross-sectional survey. Setting Online. Participants Individuals with self-reported, treated hypothyroidism. Intervention Questionnaire. Main Outcome Measures Type D personality and associations with baseline characteristics, control of the symptoms of hypothyroidism by medication, satisfaction with care and treatment of hypothyroidism, impact of hypothyroidism on everyday living. Results A total of 3915 responses were received, 3523 of which were valid. The prevalence of type D personality was 54.2%. Statistically significant associations were found between type D personality and several respondent characteristics (age, marital status, ethnicity, household income, comorbidities, type of treatment for hypothyroidism, most recent TSH level), anxiety, depression, somatization, poor control of the symptoms of hypothyroidism by medication, dissatisfaction with care and treatment of hypothyroidism, and a negative impact of hypothyroidism on everyday living). Discussion Our study found a high prevalence of type D personality among people with hypothyroidism who responded to the survey. Type D personality may be an important determinant of dissatisfaction with treatment and care among people with hypothyroidism. Our findings require independent confirmation. Close collaboration between the disciplines of thyroidology and psychology is likely to be key in progressing our understanding in this area.