Persistent hypoparathyroidism is an underestimate but major complication of total thyroidectomy. The hypothesis of the investigators is that the mental health is impaired in hypoparathyroid patients compared with thyroidectomized patients without hypoparathyroidism. The investigators evaluated the quality of life using the SF-36 survey in comparison with a control population of patients thyroidectomized but free from this complication. The voice quality, the cardiovascular risk, the kidney function and the incidence of urinary lithiasis were also evaluated.

Persistent hypoparathyroidism is an underestimate but major complication of total thyroidectomy. In this retrospective, observational, multicentre study, the investigators evaluated the quality of life using the SF-36 survey in comparison with a control population of patients thyroidectomized but free from this complication. Patients in six centers in France (Angers, Le Mans, Limoges, Nancy, Nantes, la Pitié-Salpétrière) and in the association "Hypoparathyroïdisme France" were contacted by mail. The primary endpoint was the mental health. The physic and global quality of life scores were assessed as secondary endpoints. Medical and VHI surveys were also send to the patients. The voice quality, the cardiovascular risk, the kidney function and the incidence of urinary lithiasis were also evaluated.

Inclusion Criteria:

• Patients operated of total thyroidectomy
• Patients suffering from persistent hypoparathyroidism defined as serum PTH inferior to 15 pg/mL 6 months after the surgery, requiring vitamin-calcic supplementation.
• Age superior to 18
• Answering the survey

Exclusion Criteria:

• Pregnancy at the time of the study
• Age inferior to 18 or adult under guardianship
• Patients with vitamino-calcic supplementation without serum PTH measurement
• Cause of hypoparathyroidism other than post-operatory.

The study population is that of hypoparathyroid patients of the Hypoparathyroidism France combination who have undergone total thyroidectomy and who have agreed to participate in the study.

Patients with permanent hypoparathyroidism who were included in the ThyrQol study and in the FOTHYR study will also be solicited. Endocrinologists at the University Hospital of Nantes also have patients with permanent hypoparathyroidism in their patients.

The control population consists of patients who had a total thyroidectomy and were included in the ThyrQol study between 2014 and 2018, without sequelary hypoparathyroidism.