Table 2.
Key clinical parameters in the studies that investigated the effect of obesity surgery on detection threshold.
| Author (year) | N | Group (s) | % Female | Age (y) | T2DM (%) | Time after Intervention (months) | Baseline BMI (kg/m2) | Weight Loss (% or kg) | Time Since Last Meal (h) | Taste Modality | Stimuli and Concentration |
Methodology | Key Results (Post vs. Pre Surgery) |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
|
Scruggs 1994 [52] |
6 10 |
RYGB NWC |
100% 100% |
34.1 ± 7.8 36.7 ± 6.9 |
? | 1, 2, 3 n/a |
44.2 ± 7.1 20.6 ± 1.9 |
15, 10, 7 kg n/a |
? | sweet sour salty bitter |
sucrose (6–5800 mM) HCl (0.5–500 mM) NaCl (6–6100 mM) urea (90–5000 mM) |
3-AFC [62] | ↑ SW a, SO, SA, BI |
|
Bueter 2011 [50] |
99 | RYGB NWC |
88.9% 77.8% |
? | ? | 2 2 |
44.8 ± 5.4 22.0 ± 3.0 |
14 kg | ? | sweet | sucrose (2.1, 6.25, 12.5, 25, 50, 100 and 300 mM) | constant stimuli [50] | ↑ SW |
|
Pepino 2014 [46] |
17 10 |
RYGB AGB |
100% 100% |
42.1 ± 8.4 46.8 ± 13.9 |
0 0 |
~20% WL ~20% WL |
46.3 ± 7.7 48.5 ± 10.5 |
20.3 ± 3.0 kg 18.4 ± 2.0 kg |
12 h | sweet salty savoury |
sucrose, glucose, NaCl, and MSG: (1 to 1 × 10−4 M) | 2-AFC [61] | ↔ SW (s, g), SA, SAV b |
|
Holinski 2015 [45] |
37/ 4/ 3 23 |
VSG/AGB/RYGB NOC |
65.9% 56.2% |
47.1 ± 9.8 39.5 ± 13.5 |
0 0 |
6 6 |
48.6 ± 7.5 23.4 ± 3.8 |
29.5 kg (20.6%) 0.1 kg (0.1%) |
? | sweet sour salty bitter |
sucrose (0.4, 0.2, 0.1 and 0.05 g/mL) citric acid (0.3, 0.165, 0.09 and 0.05 g/mL) NaCl (0.25, 0.1, 0.04 and 0.016 g/mL) quinine HCl (0.006, 0.0024, 0.0009 and 0.0004 g/mL) |
Burghart taste strip [63] | ↑ SW, SO, SA, BI b |
|
Altun 2016 [54] |
52 | VSG | 57.7% | 38.5 ± 9.4 | ? | 1, 3 | 45.8 ± 7.2 | 1m: 25 ± 7.1% c 3m: 43.9 ± 10.3% c |
1 h | sweet sour salty bitter |
sucrose (0.4, 0.2, 0.1, 0.05 g/mL) citric acid (0.3, 0.165, 0.09, 0.05 g/mL) NaCl (0.25, 0.1, 0.04, 0.016 g/mL) quinine HCl (0.006, 0.0024, 0.0009, 0.0004 g/mL) |
Burghart taste strip [63] | ↑ SW, SO, SA, BI |
|
Ekmekcioglu 2016 [60] |
19 29 |
RYGB/SAGB NOC |
63.6% 48.3% |
46.3 ± 10.0 41.0 ± 12.8 |
30.3% 0 |
3 n/a |
43.2 ± 5.7 23.6 ± 3.0 |
21.8% n/a |
? | salty | NaCl (~0.003 to ~0.034 mol/L or ~0.16 g/L to ~2 g/L) | 3-AFC [62] | ↑ SA |
|
Nance 2017 [58] |
23 8 |
RYGB VSG |
87.0% 87.5% |
43.0 ± 9.6 36.6 ± 9.9 |
0 0 |
~20% WL ~20% WL |
46.9 ± 7.5 53.3 ± 8.7 |
19.8 ± 3.7% 19.3 ± 1.8% |
12 h | sweet salty savoury |
sucrose, glucose, NaCl, and MSG: (1 × 10−4 to 1 M) | 2-AFC [61] | ↔ SW, SA, SAV |
|
Abdeen 2018 [48] |
14 10 |
VSG OOC |
71.4% 40.0% |
15.0 ± 1.9 15.1 ± 1.8 |
? | 3, 12 3 |
49.6 ± 5.9 32.0 ± 5.1 |
3m: 19.9 ± 1.2% 12m: 35.8 ± 1.3% |
12 h | sweet | sucrose (2.1, 6.25, 12.5, 25, 50, 100, AI9300 mM) | constant stimuli [50] | ↔ SW |
|
Nielsen 2019 [51] |
21 8 29 |
RYGB VSG NOC |
100% 100% 100% |
37.1 ± 9.9 45.0 ± 9.5 40.0 [10.4] |
0 0 0 |
1.5, 6, 18 1.5, 6, 18 n/a |
47.9 ± 6.5 43.5 ± 4.6 22.1 ± 2.4 |
18 m: 42.3 kg 18 m: 22.7 kg n/a |
1 h | sweet | sucrose (0 g/L, 0.34 g/L, 0.55 g/L, 0.94 g/L, 1.56 g/L, 2.59 g/L, 4.32 g/L, 7.2 g/L, 12 g/L) | 2-AFC [61] | ↔ SW b ↑ SW d ↔ SW e |
Abbreviations: 2-AFC: two-alternative, forced-choice test, 3-AFC: 3-alternative forced choice test, AGB: adjusted gastric band, BI: bitter, BMI: body mass index, g: glucose, h: hour, HCl: hydrochloric acid, kg: kilogram, m: month, M: mol/L, mM: mmol/L, n/a: not applicable, NaCl: sodium chloride, NOC: non-obese control, NWC: normal weight control, SAGB: single-anastomosis gastric bypass, OOC: overweight/obese control, RYGB: Roux-en-Y gastric bypass, s: sucrose, SA: salty, SAV: savoury, SO: sour, SW: sweet, T2DM: type 2 diabetes mellitus, VLCD: very low-calorie diet, VSG: vertical sleeve gastrectomy, WL: weight loss, y: years. Data given as mean ± SD or median (interquartile range). Footnotes: a Post 1 and 2 months, but not post 3 months. b Combined both groups. c % excess weight loss. d RYGB group only. e VSG group only. ? data not reported.