Supplemental File, Ueland et al. Bone resorption following weight loss surgery is associated with treatment procedure and changes in secreted Wnt antagonists

Participants and study design

Details on the lifestyle intervention

As stated in the original publication (1) “The majority (59/63) of patients in the lifestyle group were referred to a rehabilitation center specializing in the care of morbidly obese patients (Evjeklinikken). Using a cognitive approach the program at this center aimed to induce a weight loss of at least 10%. Each patient was motivated to increase their physical activity and to normalize their eating habits. The one year lifestyle program comprised of four stays at the rehabilitation center lasting for either one week or four weeks (Figure 2). The daily program was divided between organized physical activity (3-4 hours) and different psychosocially oriented interventions. The interventions involved individual consultations with a medical doctor, nutritionist, physiotherapist and a trained nurse. Those leading the counselling interviews were trained in motivational interviewing, a client-centered counselling style which aims to invoke behavior change. The patients also took part in group sessions focusing on emotional aspects of sedentary behavior as well as classroom lessons on topics related to nutrition, physical activity and co-morbidities. No special diet or weight loss drugs were prescribed, but patients were encouraged to follow the guidelines of the Norwegian National Council of Nutrition which recommend that the daily intake of protein, fat, carbohydrate, and alcohol should account respectively for 10-20%, < 30%, 50-60%, and < 5% of energy consumed. Outside of these stays patients were contacted by phone once every two weeks. They were encouraged to self-monitor their eating habits and physical activity, as well as to visit their general practitioner for a consultation and weight control check once every four weeks. The remaining four participants were allocated to two rehabilitation centers with comparable intervention programs. Fifty-four patients (86%) attended all scheduled center visits.”

Details on the postoperative supplements

Standardized postoperative supplements were prescribed and consisted of 1 daily multivitamin/mineral

pill (vitamin content 1.4 mg B1, 1.6 mg B2, 2 mg B6, 200 g folate, 1g B12, 60 mg C, 500 g A, 5 µg D3, and 10 mg E, Collett Kostpluss, Axellus, Oslo, Norway), chewable vitamin D/calcium tablets taken morning and evening (each containing 10 µg D3/500 mg calcium carbonate, Calcigran Forte, Nycomed Pharma, Oslo, Norway), iron (65 mg ferrous sulfate, 130 mg in women, Ferromax, Weifa, Oslo, Norway), and fish oil capsules (250 g A, 10 µg D3, and 10 mg E, Møller’s Dobbel, Axellus). Vitamin B12 was given intramuscularly every 3 months (1 mg cyanocobalamin, Betolvex, Actavis Norway, Oslo, Norway).

Results

Supplemental Table 1. Nutrient substitution at baseline and 1 year.

Lifestyle / Surgery / P-value
Calcium/vitamin D / Baseline / 2 (3.2 %) / 2 (2.7%) / 1.000
1 year / 2 (3.2 %) / 58 (79,5 %) / <0.001
Fish oil / Baseline / 2 (3.2 %) / 5 (6.8 %) / 0.452
1 year / 20 (31.7 %) / 59 (79.7 %) / <0.001
B12 injection / Baseline / 1 (1.6 %) / 0 (0.0 %) / 0.460
1 year / 0 (0.0 %) / 63 (85.1 %) / <0.001
Iron / Baseline / 0 (0.0 %) / 1 (1.4 %) / 1.000
1 year / 2 (3.2 %) / 46 (62.2 %) / <0.001
Multi-vitamin / Baseline / 3 (4.8 %) / 6 (8.1 %) / 0.506
1 year / 17 (27.0 %) / 68 (99.9 %) / <0.001

Supplemental Table 2. Change in bone turnover markers from baseline to 1 year in users and non-users of micro-nutrients within the surgery group

Non-users / Users / P-value
Fish oil / NTx change / 5.54±5.69 / 7.54±4.19 / 0.145
OC change / 2.4±3.98 / 2.77±2.53 / 0.653
P1NP change / 43.15±48.38 / 33.49±27.72 / 0.312
B12 injection / NTx change / 6.45±4.45 / 8.19±4.68 / 0.254
OC change / 2.07±2.3 / 2.8±2.94 / 0.437
P1NP change / 21.91±41.4 / 37.81±30.83 / 0.140
iron / NTx change / 7.56±4.99 / 8.16±4.48 / 0.592
OC change / 2.5±3.14 / 2.81±2.69 / 0.655
P1NP change / 34.2±25.53 / 36.21±36.75 / 0.800
Multivitamin / NTx change / 6.4±4.6 / 8.07±4.67 / 0.404
OC change / 0.95±1.06 / 2.85±2.91 / 0.120
P1NP change / 29.1±28.11 / 36.01±33.29 / 0.624

Supplemental Table 3. Serum levels of bone and metabolic markers at baseline 1 year follow-up in patients with morbid obesity treated with gastric bypass receiving vs. not receiving calcium/vitamin D supplementation at one year.

No calcium/vitamin D (n=15) / calcium/vitamin D (n=58) / P-
Baseline / 1 year / Change / Baseline / 1 year / Change / value
BMI (kg/m2) / 45.6±1.2 / 32.9±1.3 / -27.8±2.3 / 46.8±0.8 / 32.5±0.7 / -30.5±1 / 0.179
P1NP (μg/L) / 49.0±5.4 / 89.7±9.6 / 40.8±9.6 / 42±2.6 / 76.6±3.7 / 34.1±4.2 / 0.910
NTx (nM/L) / 23.3±1.8 / 31.2±1.9 / 7.9±1.0 / 20.4±0.7 / 28.6±0.8 / 8.0±0.6 / 0.625
OC (ng/mL) / 2.78±0.33 / 5.37±1.05 / 2.59±0.96 / 2.64±0.17 / 5.39±0.36 / 2.75±0.35 / 0.442
SOST (ng/mL) / 0.58±0.05 / 0.56±0.05 / -0.03±0.02 / 0.62±0.03 / 0.57±0.03 / -0.04±0.01 / 0.690
DKK (ng/mL) / 0.73±0.1 / 1.00±0.38 / -0.06±0.1 / 1.41±0.31 / 1.41±0.31 / -0.03±0.1 / 0.755
OPG (ng/mL) / 3.14±0.39 / 2.80±0.30 / -0.34±0.37 / 3.39±0.18 / 2.99±0.14 / -0.37±0.17 / 0.957
VitD25OH (nM) / 50±8 / 52±6 / 2.07±8.41 / 48±2 / 64±3 / 15.85±3.06 / 0.063
PTH (pg/mL) / 5.9±0.5 / 6.7±0.7 / -0.13±0.57 / 6.3±0.3 / 6.1±0.4 / -0.81±0.23 / 0.163
Calcium / 2.37±0.01 / 2.36±0.01 / -0.02±0.02 / 2.33±0.01 / 2.35±0.01 / 0.01±0.01 / 0.158
CRP (mg/L) / 4.4±1.1 / 0.9±0.4 / -3.5±1.2 / 4.0±0.4 / 1.2±0.3 / -2.8±0.4 / 0.596
IL1Ra (pg/mL) / 360±73 / 141±27 / -219±67 / 359±34 / 199±24 / -156±26 / 0.275
IGF1 (ng/mL) / 76.9±7.5 / 83.7±5.4 / 6.7±7.1 / 72.5±3.7 / 73.8±4.4 / 0.1±4.2 / 0.189
IGFBP3 (μg/mL) / 7.1±1.0 / 6.0±0.6 / -1.1±0.8 / 7.1±0.6 / 5.6±0.3 / -1.5±0.4 / 0.417

Abbreviations: NTx, N-terminal peptide; OCN, osteocalcin; P1NP, procollagen type 1 N-terminal propeptide; SOST, sclerostin,; DKK1, Dickkopf homolog 1; OPG, osteoprotegerin; PTH, parathyroid hormone; (PTH), calcium, albumin corrected calcium; CRP, C-reactive protein, IL-1Ra, interleukin 1 receptor antagonist; IGF1, insulin-like growth factor 1, IGFBP3, insulin-like growth factor-binding protein 3.

Supplemental Table 4. Predictors of change

in NTx within the lifestyle and surgery group.

Dependent / NTx
Lifestyle / Surgery
BMI (%) / -0.51**
(t=-3.7) / -0.28*
(t=-2.5)
Physical
activity / -0.28**
(t=-2.1) / -0.08
(t=-0.7)
VitD suppl. / 0.06 / 0.02
OCN / 0.39**
(t=3.2)
SOST / 0.39**
(t=3.6)
DKK1† / 0.35**
(t=3.2)
R-square / 0.41 / 0.40

Data are given as standardized coefficients with t in parenthesis.

Vitamin D supplementation (merged ca/vitamin D and cod oil):

stopped = -1, no change = 0, started = 1. Change in BMI, physical

activity and Vit D/calcium supplementation entered as forced in step 1,

while the rest of the metabolic markers inluded stepwise in step 2.

*p<0.05, **P<0.01. †DKK1 included minus three outliers (>±3SD from mean).

Reference List

1. Hofso D, Nordstrand N, Johnson LK, Karlsen TI, Hager H, Jenssen T, Bollerslev J, Godang K, Sandbu R, Roislien J, Hjelmesaeth J. Obesity-related cardiovascular risk factors after weight loss: a clinical trial comparing gastric bypass surgery and intensive lifestyle intervention. Eur. J. Endocrinol. 163, 735-745 (2010)