. 2020 Jul 24;4(8):e10391. doi: 10.1002/jbm4.10391

Table 2.

Population‐Based Studies of the Prevalence and Complications of Normocalcemic Hyperparathyroidism

Study	Years	Country	Total cohort (n)	Baseline prevalence	Follow‐up duration (years)	Follow‐up prevalence	Mean Age	F/M ratio	PTH (pg/mL)	S‐Ca (mg/dL)	S‐P (mg/dL)	S‐25‐(OH)D (ng/mL)	S‐1,25‐(OH)₂D (pg/mL)	eGFR (mL/min)	Bone complications	Renal stones	Notes
Lundgren et al.⁽ ²⁸ ⁾	1991‐1992	Sweden	5771	0.54%	NR	NR	Range 55‐75 (overall population)	100% F	85.1 ± 40.64	2.52 ± 0.07 mmol/L	NR	NR	NR	NR	NR	NR	Used both ionized calcium and albumin‐adjusted calcium. Tested on 3 or more occasions.
Berger et al.⁽ ²⁹ ⁾	1995‐2007	Canada	1872	3.31%	NR	NR	71.7 ± 2.4 (69.3‐74.2)	NR	>10.2 pmol/L, no mean values provided	Normal	NR	70 ± 25nmo/L (all participants)	NR	79.2 (76.3‐82.2)	No difference from control group; elevation of BSAP similar to secondary hyperparathyroidism; total hip BMD lower in those with higher PTH levels	12.4% of males in total cohort, 6.3% of females in total cohort; unknown in NHPT group	6.45% taking glucocorticoids, 45% on antiresorptive drugs, 26% on diuretics. Urine calcium/urine creatinine=0.42. Tested only on one occasion.
Kontogeorgos et al.⁽ ³⁰ ⁾	1995‐2009	Sweden	608	2%	13	0.2%	53.3 ± 9.0	NR	73.4 ± 14.2 ^a	2.34 ± 0.08 mmol/L ^a	NR	≥20 65.8 ± 13.8 nmol/L ^a	118.5 ± 42.7 pmol/L ^a	Normal	No difference in past history of fracture; 2/7 sustained fractures during follow‐up	NR	Calcium not adjusted for albumin; 1 patient developed hypercalcemia with PTH inappropriately normal and increased vitamin D. No use of ionized or urinary calcium. Single measurements of blood samples.
Palermo (OPUS Study) et al.⁽ ³¹ ⁾	1999‐2001	5 European Centers	2419	0.1% (1 patient)	6	0	NR	100% F	NR	NR	NR	≥20	NR	>60	NR	NR	Albumin‐adjusted calcium only. Tested only once at baseline.
Cusano DHS et al.⁽ ³² ⁾	2000‐2010	US	3450	3.1%	8	0.6%	41.3 ± 12	38% F	>55 94.8 ± 46	9.3 ± 0.6	3.1 ± 0.6	≥20 30.1 ± 11	NR	>60 (creatinine 0.93 ± 0.1)	No difference in OPG or CTX between patients and controls	NR	Albumin‐adjusted calcium only; no thiazides or lithium; single lab value for basal cohort. Of 64 patients with follow‐up, only 1 developed hypercalcemia (1.5%), and 49 (76.5%) were reclassified as normal or with SHPT. Lab measurements only once at baseline and follow‐up.
Cusano MrOS et al.⁽ ³² ⁾	2000‐2002	US	2503	0.36%	NR	NR	70 ± 6	100% M	>66 77.5 ± 13	9.4 ± 0.6	3.0 ± 0.5	≥20 25.2 ± 5	NR	>60 1.0 ± 0.1	No differences from normal population re: BMD, P1NP, CTx or TRAP‐5b	NR	Albumin‐adjusted calcium only; no thiazides; single basal lab value.
Rosario et al.⁽ ³³ ⁾	2009‐2014	Brazil	676	0.6%	NR	NR	53	80% F	95.3(76‐112)	9.8	NR	≥30	NR	>60	Exclusion criteria: History of pathological fractures	Exclusion criteria: History of nephrolithiasis or nephrocalcinosis	Use of ionized calcium; 80% (4/5 patients) NHPT showed evidence of pathologically confirmed parathyroid adenoma(s) at thyroid‐related surgery. Lab measurements repeated a second time, but temporal distance unknown.
Vignali et al.⁽ ³⁴ ⁾	2010	Italy	685	0.4%	NR	NR	47.0 ± 22.9	100% M	133 ± 5	8.9 ± 0.1	NR	≥30 37.5 ± 5.3	NR	>60 96.5 ± 26.1	NR	NR	Albumin‐adjusted calcium only; Exclusion of bisphosphonates and thiazides. 1 out of the 3 patients with NHPT had an estimated calcium intake of 107 mg/day.
Garcia‐Martin et al.⁽ ³⁵ ⁾	Unknown (1 year)	Spain	100	6%	1	6%	56.3 ± 3.2	100% F healthy, PMP²	81.3 ± 10	8.9 ± 0.2	3.3 ± 0.4	≥30	NR	80 ± 13	No difference from control group; BMD estimated by QUS; NHPT and SHPT cohorts showed negative correlation of PTH and BMD by QUS	0% at baseline and follow‐up	Albumin‐adjusted calcium; single lab value for definition; no other criteria specified other than healthy.

BSAP = Bone‐specific alkaline phosphate; CTX = C‐terminal telopeptide; NR = not recorded; OPG = Osteoprotegerin; P1NP = procollagen 1 N‐terminal propeptide; PMP = postmenopausal; QUS = quantitative ultrasound; SHPT = secondary hyperparathyroidism; TRAP‐5b = tartrate‐resistant acid phosphatase 5b.

^{^a}

Biochemical data from patients at follow‐up.