Table 2.

Longitudinal studies on the effects of bariatric surgery on incretin levels

Reference	Population	Surgery type	Follow-up duration	Outcome
Barry et al. [58]	>300 lb, n=12	JIB	3–6 weeks	↑ Fasting EG by 3 weeks ↑ Postprandial EG by 6 weeks
Jorde et al. [77]	n=5	JIB	2–6 weeks	↓ Postprandial GIP
Schrumpf et al. [142]	n=9	GBP	3–12 months	No change in GIP levels at 3 or 12 months
Sirinek et al. [76]	n=12	GBP	3–4 months	↓ Fasting, postprandial GIP
Kellum et al. [59]	n=9	GBP	11 months	↑ Postprandial EG
Kellum et al. [59]	n=7	VBG	11 months	No effect on fasting, postprandial EG
Rubino et al. [61]	n=9, 6 with T2DM	GBP	3 weeks	↓ Fasting GIP in T2DM patients only No change in fasting GLP-1
Clements et al. [63]	n=20 with T2DM	GBP	2–12 weeks	↓ Fasting GIP by 6 weeks No significant effect in fasting GLP-1
Valverde et al. [65]	n=19	BPD	1–6 months	↑ Fasting, postprandial GLP-1by 6 months
Valverde et al. [65]	n=12	VBG	1–6 months	No effect on fasting, postprandial GLP-1
Guidone et al. [66]	n=10 with T2DM	BPD	1–4 weeks	↓ Fasting, postprandial GIP by 1 week ↑ Fasting, postprandial GLP-1 by 1 week
Morinigo et al. [69]	n=9	GBP	6 weeks	↑ Postprandial GLP-1
Morinigo et al. [68]	n=34	GBP	6 weeks, 12 months	↑ Postprandial GLP-1 by 6 weeks
Borg et al. [70]	IR, n=6	GBP	1–6 months	↑ Postprandial EG, GLP-1 by 6 months
le Roux et al. [71]	n=16	GBP	2–42 days	↑ Postprandial GLP-1 by 2 days
Laferrere et al. [64]	n=8 with T2DM	GBP	1 month	↑ Postprandial GLP-1, GIP ↑ IE
Reinehr et al. [67]	n=19	GBP	2 years	↓ Fasting GLP-1
Whitson et al. [143]	n=10, 5 with T2DM	GBP	6 months	↑ Nonfasted GLP-1 in T2DM only
Laferrere et al. [62]	n=9 with T2DM	GBP	1 month	↑ Postprandial GLP-1, GIP ↑ IE
Shak et al. [75]	n=24	GB	6–12 months	No change in GLP-1, GIP

JIB jejunoileal bypass, EG enteroglucagon, GIP gastric inhibitory peptide, VBG vertical banded gastroplasty, T2DM type 2 diabetes mellitus, GBP gastric bypass, GLP-1 glucagon-like peptide-1, BPD biliopancreatic diversion, IR insulin resistant, IE incretin effect, GB gastric banding