Several studies have demonstrated beneficial effects of continuous glucose monitoring (CGM) in patients with type 1 diabetes mellitus (T1DM).1–3 In most of the studies, however, a subgroup of patients uses CGM less than recommended or discontinues use. To facilitate treatment adherence in this patient group, thorough understanding of motives for CGM termination is a prerequisite, but only little is known about mechanisms underlying patient adherence to CGM.4–6
Psychosocial factors may affect CGM use because of the constant efforts required of the user to benefit from CGM. To pursue this hypothesis, we invited 24 adults with T1DM from our clinic to take part in a focus group study. Twenty-five ± four months previously, patients had participated in the multicenter Eurythmics Trial2 and started using sensor-augmented pumps (SAPs) during (intervention group) or immediately after completion of the trial (control group). Sensor-augmented pump costs were covered by the Danish health care system. Sixteen patients agreed to participate in the focus group study (Table 1). Twelve were still using SAPs, while four had chosen to cease CGM and continue insulin pump treatment only. Three focus groups were formed based on self-reported CGM use: two groups of current CGM users (six persons in each) and one group of former CGM users (four persons). “CGM use” was defined as sensor use >60% of the time in the past three months.
Table 1.
Patient Characteristicsa
| SAP users | Former SAP users | |
|---|---|---|
| n | 12 | 4 |
| Female sex | 5 (41.7) | 3 (75.0) |
| Age (years) | 40 ± 13 | 39 ± 13 |
| White race | 12 (100) | 4 (100) |
| Diabetes duration (years) | 22 ± 12 | 18 ± 4 |
| HbA1c (%) | 7.1 ± 0.6 | 7.3 ± 0.3 |
| Length of insulin pump treatment (months) | 24 ± 4 | 27 ± 1 |
| Length of CGM use (months) | 24 ± 4 | 8 ± 5 |
Data are n (%) or means ± standard deviation.
The most notable observation during the focus group sessions was that personal ambitions for metabolic control clearly differed between former and current CGM users. Patients who had discontinued CGM utilization were aware that they could have better metabolic control using CGM; nevertheless, they chose not to. A former user stated: “I know that the sensor improves my hemoglobin A1c (HbA1c)… Intellectually I know that I should wear it. Why don’t I? Now that’s a good question.” Conversely, none of the current users were willing to stop CGM at the expense of a rise in HbA1c. “I want to live a little longer, and I want to be free of all the late complications, so in that respect I don’t think that I have much to negotiate with,” a current CGM user said.
All participants praised the glucose curve on the pump display and the arrows indicating rises and falls, but a major complaint coming from both current and former SAP users was CGM inaccuracy. The expression “false security” was used, and two SAP users stated: “I don’t trust it 100% any longer.” “Neither do I. I use it mostly as a guideline.” Continuous glucose monitoring alarms were also vigorously discussed. In particular, alarms caused by inaccurate sensor readings were considered irrelevant interruptions, but also hypo- and hyperalarms that continued after the blood glucose had been corrected due to the inherent time lag of the sensor. Interestingly, former and current users reported different ways of coping with CGM alarms, and the current users seemed less disturbed by alarms. A SAP user explained: “I mute it. You can still follow [the glucose curve] on the display.” In contrast, a former user said: “These nightly alarms…I think you can turn them off, but I never figured out how.”
A third important point was that body image played a crucial role for patients in all groups, and to some, it was the most limiting factor of CGM use.
Based on this focus group study, we propose that pre-CGM counseling focusing on patient motivation, alarm coping strategies, and body image may increase CGM adherence.
Acknowledgments
We recognize the efforts of the patients and thank them for their participation. Special thanks to Merete Meldgaard, R.N., Hvidovre University Hospital, for contributing to the development of the focus group topics and questioning route, and to Birthe Gade-Rasmussen, M.D., Hvidovre University Hospital, for verifying agreement between focus group transcripts and the summary presented in this letter.
Glossary
- (CGM)
continuous glucose monitoring
- (HbA1c)
hemoglobin A1c
- (SAP)
sensor-augmented pump
- (T1DM)
type 1 diabetes mellitus
References
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