A 38-year-old woman presented with tremor and anxiety 3 weeks into her pregnancy and was diagnosed with thyrotoxicosis. One year postpartum, the thyroid appeared multinodular with a dominant nodule that showed deficient uptake on the technetium scan. Her thyroid function was normal and thyroid peroxidase antibodies were negative. She developed an enlarging goitre and underwent total thyroidectomy following which she developed persistent hypocalcaemia and hypomagnesaemia.
She represented with similar to her gestational symptoms, 3 months later. Her free T4 was 25 pmol/l and her symptoms were attributed to metabolic causes. Despite normal thyroid profile and electrolytes her symptoms deteriorated. A psychiatric review concluded that her symptoms were associated to a generalised anxiety disorder.
Thyroid has an important effect on cognition and mood. Hypothyroidism is associated with depression that can improve with treatment although full resolution is uncertain. Neuropsychiatric symptoms can persist in thyrotoxicosis despite maintaining a euthyroid state.
Up to 7% of women can develop postpartum thyroid dysfunction. Antibodies against thyroid peroxidase can be a marker of postpartum depression.
Post-operative cognitive dysfunction is common in advanced age and possibly caused by cerebral microemboli. Although neuropsychiatric changes following major surgery are known, there is not a well established association between anxiety disorders and minor surgery.
Generalised anxiety disorder is associated with headache, paraesthesia, insomnia, tremor, fatigue, difficulty in concentration, sweating, palpitations, dyspnoea, nausea, urinary frequency, body pains and anxiety. It results from a combination of genetic propensity and stressful environmental conditions that can alter the function in amygdala and cingulated gyrus and increase the cortisol levels and sympathetic activity. Some studies support that the persistence of neuropsychiatric symptoms, despite the withdrawal of the triggering event, can be associated with permanent changes in the brain.
Cases like this should potentiate our vigilance in the early recognition and management of such symptoms.