Treatment of Nonagenarians with Primary Hyperparathyroidism.

Abstract

To the Editor: The 2010 U.S. Census estimated that there were 1.9 million Americans aged 90 and older—approximately 4.7% of the population aged 65 and older. It is predicted that this age group will account for approximately 10% of the elderly population by 2050.1 As a result, there is a growing focus on the diseases that affect this population. An endocrine disorder frequently encountered in elderly adults is primary hyperparathyroidism (PHPT).2 Although parathyroidectomy remains the only definitive cure for PHPT, there is often reluctance to pursue surgical options in elderly adults because of concerns about age and comorbidities.3 Medical management is a less-well-studied option in elderly adults with PHPT. The objective of the current study was to present two cases of PHPT first diagnosed over the age of 90 and managed using conservative treatment. A 92-year-old woman with a history of hypothyroidism and vertebral compression fractures was evaluated because of a calcium level of 11.1 mg/dL (normal 8.6–10.4 mg/dL). Results of the hypercalcemia assessment were ionized parathyroid hormone (iPTH) 130 pg/mL (normal 9–76 pg/mL), 25-hydroxy vitamin D (25-OH(D)) 21 ng/mL (normal 25–80 ng/mL), 24-hour urine calcium 204 mg/24 h (normal 50–400 mg/24 h), parathyroid hormone–related protein less than 2.1 pmol/L (normal 0–4 pmol/L), and creatinine 1.0 mg/dL (normal 0.5–1.2 mg/dL). T-scores were −4.7 at the lumbar spine and −2.7 at the femur. Sestamibi scan located high parathyroid activity in the lower left thyroid region, consistent with a parathyroid adenoma. She was an appropriate surgical candidate but declined an invasive procedure. She was then conservatively managed with serial monitoring of calcium and iPTH levels. Calcium ranged from 10.2 to 10.5 mg/dL and iPTH from 147 to 211 pg/mL. Because of the severity of her osteoporosis, she was also treated with two zoledronic acid infusions. There were no further fractures during a follow-up period of 4 years. A 91-year-old man with a history of diabetes mellitus, hypertension, and dementia presented with hypercalcemia (calcium 10.7 mg/dL and 11.3 mg/dL; normal 8.4–10.2 mg/dL). The results of the hypercalcemia evaluation were consistent with PHPT: 25-OH(D) 26 ng/mL (normal 30–100 ng/mL), urine calcium 203 mg/24 hours (normal 100–300 mg/24 hours), iPTH 58.8 pg/mL (normal 14.0–72.0 pg/mL), calcium 11.1 mg/dL, creatinine 1.4 mg/dL (normal 0.6–1.5 mg/dL), phosphorous 2.3 mg/dL (normal 2.7–4.5 mg/dL), and magnesium 2.0 mg/dL (normal 1.6–2.4 mg/dL). Because of age, medical comorbidities, asymptomatic presentation, minimally high calcium levels, and normal urine calcium levels, he was monitored with serial calcium levels. Follow-up laboratory data 7 months after initial values demonstrated a stable calcium level of 10.9 mg/dL. There is no consensus regarding the optimal treatment of PHPT in elderly adults. Surgical excision of the pathological parathyroid gland(s) has been widely explored in this population. It is more often delayed and less frequently performed in older adults.3, 4 Although this is expected to some degree because of the number of medical comorbidities, older age itself is an independent predictor of less-frequent parathyroidectomies.3 Even a surgical referral for symptomatic disease was delayed an average of 5 years in older adults,4 but an increasing amount of medical literature supports parathyroidectomy. There was a good rate of successful surgeries, symptomatic relief, and better quality of life, and rates of morbidity, mortality, and complications were comparable with those of younger adults.5-7 There is a relative paucity of evidence for the optimal nonsurgical treatment of PHPT. These options are important to consider in individuals who are not surgical candidates or those who decline surgery. Calcimimetics and alendronate have been demonstrated to improve several parameters of PHPT.8, 9 Cinacalcet has been found to decrease calcium and parathyroid hormone levels.8 Alendronate has been shown to increase bone mineral density in individuals with PHPT.9 A case series highlighting the treatment options for individuals aged 79–87 with symptomatic hypercalcemia suggested a management algorithm that included surgical consideration and medical management with bisphosphonates and calcimimetics.10 Primary hyperparathyroidism is less well studied in nonagenarians than in younger individuals, but with predicted population increases in older adults, treatment options will have to be addressed more specifically for these individuals. The cases described above are individuals who were first diagnosed in their 90s with PHPT. Both were medically managed using serial calcium monitoring and did well with conservative management. There were no fractures or other complications of PHPT in the follow-up period of 7 months to 4 years. Therefore, nonsurgical medical management is a feasible therapeutic alternative to consider for nonagenarians with PHPT. Abstract version and poster were presented at the 98th Annual Meeting of the Endocrine Society, April 3, 2016, Boston, Massachusetts. Conflict of Interest: None. Author Contributions: Wong, Wang: study concept and design, acquisition of subjects and data, analysis and interpretation of data, preparation of manuscript. Sponsor's Role: N/A.