Table 1.
Detailed characteristics of included studies (n = 12)
| Study | Design | Sample size | Surgery | Age (years ± SEM) | Sex (M/F) | Diabetes (diabetes/remission/no prior diabetes) | Definition of hypoglycaemia | Test meal | Outcome on incretin hormones |
|---|---|---|---|---|---|---|---|---|---|
| Goldfine | Case-control | 21 | RYGB | 48 ± 3 | 4/17 | 0/0/21 | Prior documented severe hypoglycaemia (severe neuroglycopenic symptoms attributable to hypoglycaemia requiring bystander assistance) | Ensure 240 ml (40 g carbohydrate, 6 g fat, 9 g protein) | Higher fasting and postprandial GLP-1 but lower postprandial GIP in hypoglycaemia group. |
| Guarino | Cohort | 35 | RYGB | 52 ± 2 | 9/24 | 9/26/0 | Plasma glucose ≤ 3.3 mmol/L following a standard meal with autonomic/neuroglycopenic symptoms | 75 g glucose drink | Comparable postprandial GLP-1 response. GIP not measured. |
| Kellogg | Cohort | 14 | RYGB | 46 ± 3 | 2/10 (2 not reported) | 1/0/13 | Plasma glucose < 3.9 mmol/L following a high carbohydrate meal with autonomic/neuroglycopenic symptoms | High carbohydrate meal (405 kcal, 79% carbohydrate, 11% fat, 10% protein) | Higher postprandial insulin following high carbohydrate meal but GLP-1 and GIP not measured. |
| Laurenius | Case-control | 16 | RYGB | 47 ± 2 | 5/11 | 0/1/15 | Prior documented severe hypoglycaemia | Liquid mixed meal (99.5 g carbohydrate, 0.1 g fat, 5.7 g protein) | Comparable postprandial GLP-1 response. GIP not measured. |
| Lobato | Cohort | 23 | RYGB | 43 ± 3 | 4/19 | 0/3/20 | Plasma glucose ≤ 3.05 mmol/L following a standard liquid mixed meal with autonomic/neuroglycopenic symptoms | Fresubin 200ml, (300 kcal, 50% carbohydrate, 35% fat, 15% protein) | Higher peak postprandial GLP-1 but no difference in GIP. |
| Poitou | Cohort | 20 | RYGB | 44 ± 3 | 4/16 | N/A | Plasma glucose ≤ 3 mmol/L following a standard liquid mixed meal with autonomic/neuroglycopenic symptoms | Fresubin 400 ml (800 kcal, 45% carbohydrate, 35% fat, 20% protein) | Comparable postprandial GLP-1 and GIP responses. |
| Salehi 2014a | Case-control | 65 | RYGB | 48 ± 2 | 10/55 | 16/16/33 | History of autonomic/neuroglycopenic symptoms following a meal | Ensure Plus, 237 ml (350 kcal, 57% carbohydrate, 28% fat, 15% protein) | Comparable postprandial GLP-1 and GIP responses. |
| Salehi 2014b | Case-control | 16 | RYGB | 46 ± 3 | 4/12 | 4/4/8 | Plasma glucose < 2.8 mmol/L following a standard liquid mixed meal with neuroglycopenic symptoms | Ensure Plus, 237 ml (350 kcal, 57% carbohydrate, 28% fat, 15% protein | Trend towards a higher postprandial GLP-1 in the hypoglycaemia group but comparable GIP responses. |
| Salehi 2019 | Case-control | 14 | RYGB | 45 ± 3 | 3/11 | 1/1/12 | Plasma glucose < 2.8 mmol/L following a standard liquid mixed meal with neuroglycopenic symptoms | Ensure Plus, 237 ml (350 kcal, 57% carbohydrate, 28% fat, 15% protein | Higher postprandial GLP-1 in the hypoglycaemia group but comparable GIP response. |
| Soeby | Case-control | 26 | RYGB | 43 ± 2 | 5/21 | 0/3/23 | Plasma glucose ≤ 3.5 mmol/L following a 50 g glucose drink with autonomic/neuroglycopenic symptoms | Fresubin 200 ml, (300 kcal, 50% carbohydrate, 35% fat, 15% protein) | Comparable postprandial GLP-1 and GIP responses. |
| Tharakan | Cohort | 28 | RYGB | 46 ± 2 | 9/19 | N/A | Prior history of hypoglycaemia fulfilling Whipple’s triad | Ensure Plus | Higher postprandial GLP-1 in the hypoglycaemia group but comparable GIP response. |
| Vaurs | Cohort | 46 | RYGB | 43 ± 3 | N/A | N/A | Plasma glucose < 2.8 mmol/L following a 75 g glucose drink with autonomic/neuroglycopenic symptoms | 75 g glucose drink | Comparable postprandial GLP-1 response. GIP not measured. |