Bones, Stones, Groans – But What About Psychiatric Overtones? The C-L Psychiatrist's Role in Diagnosing Primary Hyperparathyroidism

Background
Primary hyperparathyroidism (PHPT) is caused by a parathyroid hormone-secreting adenoma which results in increased serum calcium leading to osteoporosis, urolithiasis, gastrointestinal disturbance, and neuropsychiatric symptoms (NPS). Endocrinology considers NPS to be "nonclassical manifestations" of PHPT, may overlook an elevated calcium, and may not refer to surgery despite literature documenting impressive improvement in postoperative NPS and quality of life.

Case
An 87 year old female nursing home resident was seen in surgical consultation for hypercalcemia with a serum calcium of 10.4 mg/dL (normal range 8.5-10.1 mg/dL). Records revealed hypercalcemia ranging from 9.8 to 10.6 over the prior 5 years and a PTH of 107 (normal range 18.5-88.0 pg/mL) 18 months prior. Serum albumin was 3.8 g/dL (normal range 3.4-5.0 g/dL). The patient endorsed poor memory, loss of concentration, and general malaise with no history of nephrolithiasis or osteopenia. She had been placed in a nursing home by family due to an inability to care for herself due to cognitive decline. A right inferior parathyroid adenoma was resected with PTH and calcium normalization. The patient and family reported no memory or concentration difficulty at her three month follow up and malaise had resolved.

Discussion
The American Association of Endocrine Surgeons (AAES) recommends parathyroidectomy for all patients with PHPT, as many as 90% of those considered "asymptomatic" by endocrinology guidelines report NPS likely related to PHPT and over 50% report significant improvement in NPS after surgery including markedly decreased rates of anxiety, depression, suicidal ideation, poor concentration, and memory problems measured by GAD-7 and PHQ-9 (McDow & Sippel, 2018). Following parathyroidectomy, PHQ-9 scores decreased by 65.6% and rates of anxiety and depression decreased from 55.6% to 15.4% and 83.3% to 30.8% respectively (Parks et al., 2017). Endocrinology guidelines do not support routine evaluation of NPS in the assessment of PHPT, nor do they consider patients experiencing NPS to be "symptomatic" and may result in overlooking an elevated calcium (McDow & Sippel, 2018). Our patient's NPS negatively impacted her ability to live independently and resulted in referral to long-term care. Diagnosis and management of PHPT improved her quality of life and restored her autonomy.

Conclusions
CL psychiatrists play a key role in diagnosing PHPT as a mildly elevated calcium may be overlooked by the primary medical team. A psychiatrist seeing a patient at any age with NPS with hypercalcemia or a calcium in the upper limits of normal should obtain a PTH. If elevated, referral to endocrine surgery is warranted as data supporting improvement in NPS of PHPT are striking. Early referral to surgery improves quality of life and alleviates disease burden.

References
McDow, A. D., & Sippel, R. S. (2018). Should Symptoms Be Considered an Indication for Parathyroidectomy in Primary Hyperparathyroidism?. Clinical medicine insights. Endocrinology and diabetes, 11, 1179551418785135. https://doi.org/10.1177/1179551418785135

Parks, K. A., Parks, C. G., Onwuameze, O. E., & Shrestha, S. (2017). Psychiatric Complications of Primary Hyperparathyroidism and Mild Hypercalcemia. The American journal of psychiatry, 174(7), 620-622. https://doi.org/10.1176/appi.ajp.2017.16111226