Depression in primary hyperparathyroidism: prevalence and benefit of surgery.

Context: Patients with primary hyperparathyroidism (PHP) often report nonspecific symptoms including mood disturbances.
Objective: The objective of the study was to determine the frequency of depression in PHP and assess its response to parathyroidectomy.
Methods: A case-control study at a referral center in Rochester, MN, performed Patient Health Questionnaire-9 (PHQ-9) assessments in observed (n = 81) and surgical (n = 88) PHP and benign nontoxic surgical thyroid disease (n = 85) at baseline and 1, 3, 6, and 12 months after surgery or the initial questionnaire in observed PHP. Baseline PHQ-9 scores and their response to surgery were evaluated.
Results: The groups were similar in gender and depression history, but PHP patients were older. Baseline PHQ-9 scores were 1.71 points higher in PHP than controls after adjusting for age and gender (P = .004). Clinically significant PHQ-9 scores (≥10) were twice as common in PHP (31.4%) compared with thyroid subjects (15.3%). Parathyroidectomy resulted in significant and sustained reductions in PHQ-9 scores, which were greater than observed PHP at all time points (P < .001). PHP patients with clinically significant PHQ-9 scores dropped to 7.4% (P < .001) and 7.6% (P < .001) at 1 month and 1 yr after parathyroidectomy. There were greater declines in PHQ-9 scores after parathyroidectomy at 1, 3, and 6 months (P < .001) and 1 yr (P = .061) compared with thyroid surgery.
Conclusions: Depression is common in patients with PHP. Parathyroidectomy results in greater improvement in PHQ-9 scores compared with thyroid surgery or observation of PHP.