The effect of parathyroidectomy on neuropsychological symptoms and biochemical parameters in patients with asymptomatic primary hyperparathyroidism.

BACKGROUND

With increased biochemical screening, primary hyperparathyroidism (pHPT) is often discovered incidentally whilst patients are asymptomatic.

OBJECTIVE

To assess the impact of parathyroidectomy on neuropsychological symptoms and biochemical parameters in people with asymptomatic pHPT, whilst controlling for the surgical procedure. PATIENTS/DESIGN/MEASUREMENTS: Twenty-four patients with asymptomatic pHPT requiring parathyroidectomy, in accordance with National Institutes for Health recommendations, were recruited prospectively. A control group of 23 subjects was recruited simultaneously from consecutive patients undergoing diagnostic hemithyroidectomy (HT) for benign thyroid nodules. Operations were performed by a single surgeon. Biochemical investigations and neuropsychological symptoms were measured preoperatively and 3 months after surgery. Neuropsychological symptoms were measured using the Hospital Anxiety (HAD-A) and Depression (HAD-D) scales and the Mood Rating Scale (MRS).

RESULTS

Postoperatively, calcium and parathyroid hormone normalized in all patients in the pHPT group. Patients with pHPT showed a significant improvement in neuropsychological symptoms with a pre- and postoperative mean change of 2·45 ± 2·57 (P < 0·05) on HAD-A, 2·79 ± 3·85 (P < 0·05) on HAD-D, and 3·2 ± 4·57 (P < 0·05) on MRS, parameters that were unaltered in the HT group. The differences between the two groups remained statistically significant after adjustment for age and sex for HAD-D (mean change 2·8, 95% CI = 0·3, 5·3, P = 0·025) and MRS (mean difference 3·5, 95% CI = 0·4, 6·7, P = 0·027) but not for HAD-A (mean difference 1·5, 95% CI = -0·8, 3·8, P = 0·20). For all three mental health scores, there were no significant associations with either age or sex.

CONCLUSIONS

Asymptomatic pHPT is associated with neuropsychological symptoms that improve after parathyroidectomy.