Secondary Hyperparathyroidism in Obese Patients Post Sleeve Gastrectomy

Figures & data

Table 1 Patients Demographic, Anthropometric, and Laboratory Values Pre- and Postoperative

Variables	Baseline n=143	Postoperative n=143	p-Value
Age (years) - mean± SD	31.30 ± 9.70	–	–
Gender - n (%)
Male	60 (42.0%)	–	–
Female	83 (58.0%)	–	–
Height (cm) - mean± SD	164.40± 9.30	–	–
Weight (kg) - mean± SD	121.56± 26.36	86.63± 20.66	0.001*
BMI (kg/m^2) - mean± SD	44.95± 8.05	31.80± 6.42	0.001*
Hgb (gm/L) - mean± SD	134.07± 16.35	135.60± 14.04	0.068
MCV (fL) - mean± SD	80.54± 6.58	81.84± 7.23	0.030*
INR (seconds) - mean± SD	1.05± 0.23	1.02± 0.08	0.538
APTT (seconds) - mean± SD	34.44± 7.78	36.28± 4.22	0.006*
Ca (mmol/L) - mean± SD	2.29± 0.15	2.33± 0.10	0.001*
PO4 (mmol/L) - mean± SD	1.07±0.18	1.2± 0.17	0.001*
PTH (pmol/L) - mean± SD	5.08± 2.04	6.13± 2.41	0.001*
Total protein (gm/L) - mean± SD	71.66± 7.39	70.40± 8.03	0.139
Albumin (gm/L) - mean± SD	36.68± 19.69	36.85± 4.81	0.920
Vitamin D (nmol/L) - mean± SD	47.38± 30.93	71.49± 31.76	0.001*
SrCr (μmol/l) - mean± SD	61.94± 13.16	59.42± 13.20	0.019*

Note: *Statistical significance was set at the level of P value <0.05.

Abbreviations: APTT, activated partial thromboplastin time; BMI, body mass index; Ca, calcium; Hgb, hemoglobin; INR, international normalized ratio; MCV, mean corpuscular volume; PO4, phosphate; PTH, parathyroid hormone; SD, standard deviation; SrCr, serum creatinine.

Table 2 Level of Laboratory Values (Ca, PO4, PTH, Vitamin D) Pre and Post Surgery

Parameter	Levels	Baseline		Post-Operative		p-value
		n	%	n	%
Ca (2.2–2.7 mmol/L)	Normal	114	79.7	131	91.6	0.546
	Low	29	20.3	12	8.4
PO4 (1.1–1.45 mmol/L)	Normal	51	35.7	106	74.1	0.038*
	Low	87	60.8	31	21.7
	High	5	3.5	6	4.2
PTH (1.6–6.9 pmol/L)	Normal	121	84.6	91	63.6	0.001*
	High	22	15.4	52	36.4
Vitamin D (50–250 nmol/L)	Normal	48	33.6	103	72.0	0.032*
	Low	95	66.4	40	28.0

Note: *Statistical significance was set at the level of P value <0.05.

Abbreviations: Ca, calcium; PO4, phosphate; PTH, parathyroid hormone.

Table 3 Association Between PTH Level and Clinical Characteristics Pre- and Post-Operatively Using Linear Regression Analysis

Variables	Univariate Analysis			Multivariate Analysis
	Β	95% CI	p-Value	β	95% CI	p-Value
Pre-operatively
Age	0.08	−0.6–0.76	0.8	–	–	–
Gender	0.03	−0.01, 0.06	0.2	–	–	–
Weight	0.00	−0.01, 0.02	0.5	–	–	–
Ca	0.85	−1.42, 3.13	0.5	–	–	–
PO4	−2.61	−4.49, −0.73	0.007*	−2.59	−4.46, −0.72	0.007*
Vitamin D	−0.01	−0.02, 0.00	0.089	−0.01	−0.02, 0.00	0.089
Post-operatively
Age	0.03	−0.01, 0.07	0.2	–	–	–
Gender	−0.25	−1.06, 0.56	0.5	–	–	–
Weight	−0.01	−0.03, 0.01	0.6	–	–	–
Ca	−6.52	−10.2, −2.85	<0.001*	−4.75	−8.36, −1.14	0.010*
PO4	2.04	−0.26, 4.34	0.081	1.90	−0.24, 4.05	0.081
Vitamin D	−0.02	−0.04, −0.01	<0.001*	−0.02	−0.03, −0.01	<0.001*

Note: *Statistical significance was set at the level of P value <0.05.

Abbreviations: β, beta coefficient; Ca, calcium; CI, confidence interval; PO4, phosphate; PTH, parathyroid.

Table 4 Comparison of Pre- and Post-Operative Vitamin D, Ca, and PO4 Levels by SHPT Status

Parameter	Pre-Operative			Post-Operative
	With SHPT N=22	Without SHPT N= 121	p-Value	With SHPT N= 52	Without SHPT N= 91	p-Value
Vitamin D - mean ±SD	39.13±20.43	48.89± 32.32	0.174	63.35±24.35	76.15±34.57	0.011*
Ca - mean ± SD	2.33± 0.21	2.28± 0.13	0.151	2.29± 0.11	2.35±0.09	0.001*
PO4 - mean ± SD	1.02± 0.19	1.08± 0.17	0.133	1.24± 0.13	1.18±0.19	0.077

Note: *Statistical significance was set at the level of P value <0.05.

Abbreviations: Ca, calcium; PO4, phosphate; SD, standard deviation; SHPT, secondary hyperparathyroidism.

Table 5 Association Between SHPT Status and Clinical Characteristics Pre- and Post-Operatively Using Logistic Regression Analysis

Variables	Univariate Analysis			Multivariate Analysis
	OR	95% CI	p-Value	OR	95% CI	p-Value
Pre-operatively
Age	1.00	0.96, 1.05	0.87	–	–	–
Gender	1.05	0.42, 2.73	0.91	–	–	–
Weight	1.00	0.99, 1.02	0.72	–	–	–
Ca	5.97	0.31, 115	0.23	–	–	–
PO4	0.11	0.01, 1.74	0.12	–	–	–
Vitamin D	0.99	0.96, 1.00	0.13	–	–	–
Post-operatively
Age	1.02	0.99, 1.06	0.25	–	–	–
Gender	0.86	0.43, 1.73	0.68	–	–	–
Weight	0.99	0.98, 1.01	0.42	–	–	–
Ca	0.00	0.00, 0.10	0.001*	0.01	0.00, 0.28	0.010*
PO4	11.1	1.22, 128	0.032	10.4	1.05, 141	0.060
Vitamin D	0.99	0.97, 1.00	0.017*	0.99	0.97, 1.00	0.062

Note: *Statistical significance was set at the level of P value <0.05.

Abbreviations: Ca, calcium; CI, confidence interval; OR, odds ratio; PO4, phosphate; SHPT, secondary hyperparathyroidism.