Let’s talk and let’s snooze! Patient-reported outcomes and sleep in type 2 diabetes

In Part I of this thesis, we provided an overview of PROMs for T2D. In chapter 2, we provided an overview of available PROMs to measure HRQoL in people with T2D. Over 160 PROMs for T2D were identified, with a large number of PROMs not measuring HRQoL at all, illustrating the poor quality and lack of consensus on which PROMs to use in research and care for people with T2D. In addition, in chapter 3, we tested if Computerized Adaptive Tests (CATs) are a solution for implementation of PROMs in T2D care. In 314 people with T2D, we assessed the psychometric properties of seven PROMIS CATs (assessing 1) Physical Function, 2) Pain Interference, 3) Fatigue, 4) Sleep Disturbance, 5) Anxiety, 6) Depression, and 7) Ability to Participate in Social Roles and Activities) that are relevant to people with T2D. Additionally, we assessed their acceptability in health care providers and people with T2D through focus groups and interviews. We showed that these CATs showed sufficient validity and reliability, though caution was advised regarding their responsiveness as our participants showed little change over our study period of six months. During the focus groups and interviews both health care providers and people with T2D suggested that CATs could serve as a conversation starter in routine care, but CATs should never replace personal consultations with a doctor. The second part of the thesis focused on sleep, which is also intricately linked to T2D. Previous research indicates associations between inadequate sleep duration, poor sleep quality, irregular sleep patterns and sleep disorders resulting in an increased risk of T2D and worse T2D progression. Research gaps exist in understanding specific aspects of sleep's contribution to T2D risk and progression, necessitating further exploration and intervention studies. In chapter 4, we therefore investigated the prevalence of self-reported insomnia symptoms and their association with metabolic outcomes, additionally exploring the possible mediating role of lifestyle factors in a prospective cohort of 1272 people with T2D. Approximately a third of the cohort indicated to experience symptoms of insomnia. Furthermore, cross-sectionally, insomnia symptoms were associated with poorer metabolic outcomes, but no prospective associations were observed. Finally, lifestyle factors only partly mediated the association between insomnia symptoms and metabolic outcomes. As the prevalence of insomnia symptoms is high in people with T2D and it is associated with metabolic outcomes, treatment of insomnia symptoms could contribute to the treatment of T2D. In chapter 5, we therefore described our randomized controlled trial on the effect of Cognitive Behavioral Therapy for Insomnia (CBT-I) on glycemic and metabolic outcomes in people with T2D, compared to care as usual. This study in 57 participants showed no statistically significant differences in glycemic and metabolic outcomes or Quality of Life (QoL), but did show a significantly larger decrease in insomnia symptoms and depressive symptoms after three and six months of cognitive behavioral therapy compared to control. Overall, this thesis emphasizes the need for Core Outcome Sets in PROMs for T2D, the value of PROMIS CATs in routine care, and the importance of addressing sleep disturbances in people with T2D in clinical practice. However, further research on relevant PROs and PROMs, especially future validation studies of diabetes-specific PROMs are needed, warranting a transdiagnostic integration of PROMs in diabetes research and clinical practice. Furthermore, sleep should become part of the standard evaluation protocol for people with T2D. In conclusion, the studies described in this thesis are an important addition to the literature and show that it is important to measure PROs or in other words - let’s talk! - as well as to sleep - let’s snooze! - in people with T2D.