A longitudinal study of fear of hypoglycaemia in adults with type 1 diabetes

To investigate fear of hypoglycaemia (FoH) longitudinally in a cross-sectional study of adult patients with type 1 diabetes. Specifically, we investigated two subgroups of patients who over 4 years either showed a substantial increase or decrease in level of FoH to identify factors associated with changes in FoH.

The Swedish version of the Hypoglycaemia Fear Survey (HFS) along with a questionnaire to assess hypoglycaemia history was sent by mail to 764 patients in 2010. The responders in 2010 (n = 469) received another set of the same two questionnaires in 2014. HbA_1c, insulin regimen, weight and creatinine from 2010 and 2014 were obtained from medical records. Those with an absolute difference in HFS scores ≥ 75th percentile were included in the subgroup analyses. Statistical analyses included one-sample t tests, chi-square and McNemar's test.

The absolute difference in the HFS total score (n = 347) between 2010 and 2014 was m = ±7.6, SD ± 6. In the increased FoH group, more patients reported a high level of moderate hypoglycaemic episodes as well as impaired awareness of hypoglycaemia in 2014 compared with the decreased FoH group. There were more subjects in the increased FoH group with insulin pumps in 2014 and in 2010. In the decreased FoH group, more patients had a high frequency of daily self-monitoring of blood glucose (SMBG) in 2010 and in 2014.

Fear of hypoglycaemia is stable across time for most patients. Changes in fear level are associated with changes in hypoglycaemia frequency. Thus, asking patients about changes in hypoglycaemia experiences is of great importance.