Fear of hypoglycaemia: defining a minimum clinically important difference in patients with type 2 diabetes.
BACKGROUND
To explore the concept of the Minimum Clinically Important Difference (MID) of the Worry Scale of the Hypoglycaemia Fear Survey (HFS-II) and to quantify the clinical importance of different types of patient-reported hypoglycaemia.


METHODS
An observational study was conducted in Germany with 392 patients with type 2 diabetes mellitus treated with combinations of oral anti-hyperglycaemic agents. Patients completed the HFS-II, the Treatment Satisfaction Questionnaire for Medication (TSQM), and reported on severity of hypoglycaemia. Distribution- and anchor-based methods were used to determine MID. In turn, MID was used to determine if hypoglycaemia with or without need for assistance was clinically meaningful compared to having had no hypoglycaemia.


RESULTS
112 patients (28.6%) reported hypoglycaemic episodes, with 15 patients (3.8%) reporting episodes that required assistance from others. Distribution- and anchor-based methods resulted in MID between 2.0 and 5.8 and 3.6 and 3.9 for the HFS-II, respectively. Patients who reported hypoglycaemia with (21.6) and without (12.1) need for assistance scored higher on the HFS-II (range 0 to 72) than patients who did not report hypoglycaemia (6.0).


CONCLUSIONS
We provide MID for HFS-II. Our findings indicate that the differences between having reported no hypoglycaemia, hypoglycaemia without need for assistance, and hypoglycaemia with need for assistance appear to be clinically important in patients with type 2 diabetes mellitus treated with oral anti-hyperglycaemic agents.
Health Services Management, Munich School of Management, Munich University, Germany. Stargardt@bwl.lmu.de
Tom
T
Stargardt
Linda
L
Gonder-Frederick
Karl J
KJ
Krobot
Charles M
CM
Alexander
D003924:Diabetes Mellitus, Type 2 / Q000097:blood / Q000188:drug therapy / Q000523:psychology*; D005239:Fear; D005260:Female; D005858:Germany; D006801:Humans; D007003:Hypoglycemia / Q000209:etiology / Q000523:psychology*; D007004:Hypoglycemic Agents / Q000009:adverse effects* / Q000627:therapeutic use; D008297:Male; D008875:Middle Aged; D017060:Patient Satisfaction / Q000706:statistics & numerical data; D036301:Qualitative Research; D011795:Surveys and Questionnaires
D007004:Hypoglycemic Agents