Prevalence of hypoglycemia during oral glucose tolerance testing in adults with cystic fibrosis and risk of developing cystic fibrosis-related diabetes

Background Hypoglycemia in cystic fibrosis (CF), in the absence of glucose‐lowering therapies, has long been identified as an important issue in the management of CF. There is currently still no unifying hypothesis for its etiology. Aim The aims of this study were to perform a 3‐h oral glucose tolerance test (OGTT) in participants with CF and (1) document glucose, insulin, glucagon, glucagon‐like‐peptide‐1 (GLP‐1), and glucose‐dependent insulinotropic peptide (GIP) release patterns within varying glucose tolerance groups during the OGTT; (2) determine the prevalence of hypoglycemic during the OGTT; and (3) define any association between hypoglycemia and patterns of insulin, glucagon, GLP‐1, and GIP release. Methods Eligible participants attending an adult CF clinic completed a 3‐h OGTT. Hypoglycemia on OGTT was defined as mild (glucose 3.4–3.9 mmol/L), moderate (glucose 3.1–3.3 mmol/L), and severe (glucose ≤ 3 mmol/L). Hormones were measured at fasting, 30, 60, 120, and 180 min. Results Twenty‐four participants completed the study, of which 7 had normal glucose tolerance, 12 had abnormal glucose tolerance, and 5 had cystic fibrosis related diabetes (CFRD). All participants had a delayed insulin response compared with normative data. All glucose tolerance groups showed appropriate and similar suppression of fasting glucagon. Four participants (17%) had mild hypoglycemic, three (13%) had moderate hypoglycemic, and eight (33%) had severe hypoglycemic. No participant with CFRD demonstrated hypoglycemic. Of the 19 participants without CFRD, 15 (79%) experienced hypoglycemic. Participants with hypoglycemic had greater peak glucose and insulin responses than those that did not have hypoglycemic, and this approached significance (p = .0625 for glucose and p = .0862 for insulin). No significant mean differences between GLP‐1 and GIP release were found. There was no relationship between hypoglycemic and modulator therapy. Conclusion Postprandial hypoglycemic was unmasked by the extension of an OGTT to 3 h. Delayed and abnormal insulin release, and ineffective counter‐regulatory action of glucagon may have a role in its etiology.

Section: Discussionmentioning

confidence: 99%

Hypoglycemia in cystic fibrosis during an extended oral glucose tolerance test

Armaghanian

Hetherington

Parameswaran

et al. 2020

“…26,27 In those who were hypoglycemic, the probability of remaining CFRD free over the subsequent 10 years, was found to be 86.1%. 27…”

Section: Endocrine Disordersmentioning

confidence: 98%

“…The hallmark of CFRD is elevated blood glucose, but hypoglycemia can also occur during screening tests. Two single center studies evaluating oral glucose tolerance tests (OGTT) found that 15% ‐29.6% of patients had hypoglycemia during OGTT, usually occurring at the 2‐hour glucose measurement . The patients with hypoglycemia were more likely to be older, male, heterozygous for deltaF508, have a higher BMI and be pancreatic sufficient .…”

Section: Multisystem Effects Of Cystic Fibrosismentioning

confidence: 99%

“…26,27 The patients with hypoglycemia were more likely to be older, male, heterozygous for deltaF508, have a higher BMI and be pancreatic sufficient. 26,27 In those who were hypoglycemic, the probability of remaining CFRD free over the subsequent 10 years, was found to be 86.1%. 27…”

Section: Endocrine Disordersmentioning

confidence: 99%

“…IQR] 1301 kcal/d vs 686; P < .0001) and proportion of energy intake (median [IQR] 44%[34][35][36][37][38][39][40][41][42][43][44][45][46][47][48][49][50][51] vs 31%[24][25][26][27][28][29][30][31][32][33][34][35][36][37][38][39][40][41][42][43]; P < .0001). Thus, while children with CF met their energy requirements and ate ample fat, this was largely due to ingestion of EDNP foods.…”

mentioning

confidence: 99%

See 2 more Smart Citations

Cystic fibrosis year in review 2018, part 2

Savant

McColley

2019

Hypoglycemia in children and young adults with cystic fibrosis during oral glucose tolerance testing vs. continuous glucose monitoring

Finn

Severn

Pyle

et al. 2023

BackgroundHypoglycemia is common in people with cystic fibrosis (pwCF) during oral glucose tolerance tests (OGTTs) and in the free‐living setting, yet its pathophysiology remains unclear.ObjectiveTo evaluate hypoglycemia in children and young adults with CF by OGTT and continuous glucose monitoring (CGM).MethodsA 3‐h OGTT was performed in children and young adults with CF and healthy controls (HC). Individuals were classified as experiencing hypoglycemia on OGTT (glucose <70 mg/dL) or not. Insulin, C‐peptide, glucose, glucagon, and incretins were measured. CGM was performed for 7 days in the free‐living setting. Measures of insulin sensitivity, beta cell function accounting for insulin sensitivity, and insulin clearance were calculated.ResultsA total of 57 participants (40 CF and 17 HC) underwent assessment. Rates of hypoglycemia by OGTT were similar in pwCF (53%, 21/40) compared to HC (35%, 6/17), p = 0.23. PwCF compared to HC had higher A1c; on OGTT higher and later glucose peaks, later insulin peaks; and on CGM more glucose variability. CF Hypo+ versus CF Hypo− had higher lung function, higher insulin sensitivity, higher beta cell function accounting for insulin sensitivity, and decreased CGM variability. When comparing CF Hypo+ to HC Hypo+, although rates of hypoglycemia are similar, pwCF had blunted glucagon responses to hypoglycemia. OGTT hypoglycemia was not associated with CGM hypoglycemia in any group.ConclusionYouth with CF have increased insulin sensitivity and impaired glucagon response to hypoglycemia on OGTT. Hypoglycemia on OGTT did not associate with free‐living hypoglycemia.