Incidence and risk factors for severe and symptomatic hypoglycemia in type 1 diabetes. Results of the HYPOS-1 study
Hypoglycemia is common in type 1 diabetes mellitus (T1DM). We aimed to update the incidence of severe and symptomatic hypoglycemia and investigate several correlated factors.
In this multicenter, observational retrospective study, the data of 206 T1DM patients from a sample of 2,229 consecutive patients seen at 18 diabetes clinics were analyzed. Sociodemographic and clinical characteristics, severe hypoglycemia in the past 12 months, and symptomatic hypoglycemia in the past 4 weeks were recorded with a self-report questionnaire and a clinical form during a routine visit. Poisson multivariate models were applied.
A minority of patients accounted for the majority of both severe and symptomatic episodes. The incidence rate (IR) of severe hypoglycemia was 0.49 (0.40–0.60) events/person-years. The incidence rate ratio (IRR) was higher in patients with previous severe hypoglycemia (3.71; 2.28–6.04), neuropathy (4.16; 2.14–8.05), long duration (>20 years, 2.96; 1.60–5.45), and on polypharmacy (1.24; 1.13–1.36), but it was lower when a complication was present. The IR of symptomatic hypoglycemia was 53.3 events/person-years, with an IRR significantly higher among women or patients with better education, or shorter duration or on pumps. The IRR was lower in patients with higher BMI or neuropathy or aged more than 50 years.
Fewer than 20 % of T1DM patients are free from hypoglycemia, with one in six having experienced at least one severe episode in the last year. The distribution is uneven, with a tendency of episodes to cluster in some patients. Severe and symptomatic episodes have different correlates and reflect different conditions.
KeywordsType 1 diabetes Hypoglycemia Incidence Risks factors
This study was organized and funded by the AMD Foundation Rome, with an unrestricted grant from Novo Nordisk.
Conflict of interest
Carlo B Giorda, Alessandro Ozzello, Sandro Gentile, Alberto Aglialoro, Anna Chiambretti, Fabio Baccetti, Francesco M. Gentile, Giuseppe Lucisano, Antonio Nicolucci and Maria Chiara Rossi declare that they have no conflict of interest.
This study was approved by Institutional Interdipartimental Ethics Committee S. Luigi Hospital of Orbassano, Italy.
Human and animal rights
All procedures were carried out in accordance with the ethical standards of the responsible committee on human experimentation (institutional and national) and with the Helsinki Declaration of 1975, as revised in 2008 .
Informed consent was obtained from all patients for being included in the study.
- 5.Beck RW, Hirsch IB, Laffel L, Tamborlane WV, Bode BW, Buckingham B, Chase P, Clemons R, Fiallo-Scharer R, Fox LA, Gilliam LK, Huang ES, Kollman C, Kowalski AJ, Lawrence JM, Lee J, Mauras N, O’Grady M, Ruedy KJ, Tansey M, Tsalikian E, Weinzimer SA, Wilson DM, Wolpert H, Wysocki T, Xing D (2009) The effect of continuous glucose monitoring in well-controlled type 1 diabetes. Diabetes Care 32(8):1378–1383. doi: 10.2337/dc09-0108 CrossRefPubMedGoogle Scholar
- 9.Levey AS, Stevens LA, Schmid CH, Zhang YL, Castro AF III, Feldman HI, Kusek JW, Eggers P, Van Lente F, Greene T, Coresh J, CKD-EPI (Chronic Kidney Disease Epidemiology Collaboration) (2009) A New Equation to Estimate Glomerular Filtration Rate. Ann Intern Med 150(9):604–612PubMedCentralCrossRefPubMedGoogle Scholar
- 14.Pedersen-Bjergaard U, Kristensen PL, Beck-Nielsen H, Nørgaard K, Perrild H, Christiansen JS, Jensen T, Hougaard P, Parving HH, Thorsteinsson B, Tarnow L (2014) Effect of insulin analogues on risk of severe hypoglycaemia in patients with type 1 diabetes prone to recurrent severe hypoglycaemia (HypoAna trial): a prospective, randomised, open-label, blinded-endpoint crossover trial. Lancet Diabetes Endocrinol 2(7):553–561CrossRefPubMedGoogle Scholar
- 20.Cherubini V, Pintaudi B, Rossi MC, Lucisano G, Pellegrini F, Chiumello G, Frongia AP, Monciotti C, Patera IP, Toni S, Zucchini S (2014) Nicolucci A; SHIP-D Study Group. Severe hypoglycemia and ketoacidosis over one year in Italian pediatric population with type 1 diabetes mellitus: a multicenter retrospective observational study. Nutr Metab Cardiovasc Dis 24(5):538–546CrossRefPubMedGoogle Scholar
- 23.Sartore G, Chilelli NC, Burlina S, Di Stefano P, Piarulli F, Fedele D, Mosca A, Lapolla A (2012) The importance of HbA1c and glucose variability in patients with type 1 and type 2 diabetes: outcome of continuous glucose monitoring (CGM). Acta Diabetol 49(Suppl 1):S153–S160CrossRefPubMedGoogle Scholar