Fear of hypoglycemia in type 1 diabetes managed by continuous subcutaneous insulin infusion: is it associated with poor glycemic control?

BACKGROUND

We surveyed the extent of fear of hypoglycemia in people with type 1 diabetes treated by continuous subcutaneous insulin infusion (CSII) and tested the hypothesis that suboptimal glycemic control during CSII is related to fear of hypoglycemia.

METHODS

We audited nonpregnant type 1 diabetes patients attending an Insulin Pump Clinic with at least 6 months' duration of CSII. In 104 eligible subjects, fear of hypoglycemia was assessed by questionnaire; 75 responded.

RESULTS

The median duration of CSII was 5 years (range, 1-29 years). Poor glycemic control (hemoglobin A1c [HbA1c] ≥ 8.5%; mean ± SD, 9.1 ± 1.0%) was present in 27%, and this group had more men than a good-control group with HbA1c < 7.0% (43% vs. 11%). Substantial fear of hypoglycemia (score > 50%) occurred in 27% of subjects, but fear of hypoglycemia was not correlated with HbA1c. The only significant correlates of fear of hypoglycemia were accumulated episodes of severe hypoglycemia (r = 0.48, P < 0.001) and rate of hypoglycemia on CSII (r = 0.48, P < 0.001). The HbA1c on CSII was correlated with multiple daily injection (MDI) HbA1c (r = 0.66, P < 0.001) and the change in HbA1c (r = 0.63, P < 0.001).

CONCLUSIONS

Fear of hypoglycemia is not correlated with, and is unlikely to be a major determinant of, HbA1c on CSII. Other factors (such as HbA1c on MDI and adherence to insulin pump procedures) are likely to be more important. Nevertheless, substantial fear of hypoglycemia is present in many CSII-treated people and may adversely affect quality of life and psychological well-being.