PTH and thyroid nodule: Compared with the symptomatic PHPT patients, the asymptomatic PHPT patients showed lower serum calcium (p < 0.05), serum chlorine (p < 0.05), alkaline phosphatase (p < 0.05), PTH (p < 0.05), and bone turnover markers (p < 0.05) but higher prevalence of thyroid nodules (70.73% versus 55.24%, p < 0.05) and PTC (15.44% versus 3.87%, p < 0.05).