Sleep is essential to promote both physical and mental health as well as quality of life. It is well documented that sociodemographic, psychological, and behavioral factors can influence sleep quality in adults. Biological sex, gender, age, ethnicity, socioeconomic status, and body mass index (BMI) can impact adult sleep. Women are more at risk for poor sleep quality compared to men1 as their sleep quality can be influenced by biological factors, such as their menstrual cycle, pregnancy, and menopause,2 as well as by socially constructed roles, such as family responsibilities.3 Sleep quality tends to decline with age,4 but this negative association between sleep quality and age could be partly explained by the fact that aging is often comorbid with health issues. People who identify as ethnic minorities are often at higher risk for poor sleep quality.5 Having a lower socioeconomic status is another risk factor for poor sleep quality.1 A high BMI is also a risk factor for sleep apnea,6 which can affect sleep quality. There is a positive association between social support and sleep among adults.7 Some adults use alcohol and cannabis as sleep aids,8 especially now that recreational cannabis use is legal in Canada. Alcohol use is associated with poor sleep quality,9 while the effect of cannabis on sleep is less clear with certain studies reporting improved, deteriorated, mixed results or no impact on sleep quality.10 Finally, the results of systematic reviews support that physical activity favors sleep quality among adults.11,12

Among people living with type 1 diabetes (PwT1D), poor sleep quality is associated with hyperglycemia,13 a major cause of microvascular and macrovascular complications.14 Results from our previous studies indicated that many adults living with type 1 (T1D) and type 2 diabetes (T2D) in Canada report poor sleep quality15 and that they are at higher risk for poor sleep quality compared to adults without diabetes.16 Adults living with diabetes from our previous studies also mentioned that adopting healthy sleep habits, such as avoiding screen use in bed, adopting a regular sleep schedule, and avoiding caffeine, alcohol, and nicotine before bedtime, is difficult,17 suggesting the need for behavioral interventions encouraging them to adopt healthy sleep habits. Yet, few studies have examined sleep quality among PwT1D and the various factors that can affect their sleep, while that information is crucial to develop interventions aimed at improving their sleep quality.

In our previous study, women living with diabetes were more at risk for having an irregular sleep schedule and having too many things to do in the evening, including taking care of children, was the main barrier to adopting a regular sleep schedule,17 and adults living with diabetes reporting a lower household income were also more likely to have poor sleep quality.15 Certain psychological factors specifically related to T1D can influence sleep quality. Fear of hypoglycemia is negatively associated with sleep quality among PwT1D.18 Diabetes-related distress is another factor that has a negative association with sleep quality in PwT1D,19 although data are sometimes contradictory.20 Among PwT1D, depression is correlated with poor sleep quality.21 Some PwT1D can experience diabetes-related stigma when they need to inject doses of insulin in public22 and experiencing stigma is associated with sleep deficiency in adults.23 Eating a small nutrient-dense snack before bedtime can improve sleep quality, particularly among PwT1D who tend to experience nocturnal hypoglycemia.24 In our previous study, caffeine consumption before bedtime was negatively associated with sleep quality in adults living with diabetes.15

Some diabetes-related factors can impact sleep quality. A study revealed that adults who had T1D for ≥10 years had better sleep quality compared to those with a more recent diagnosis.21 Continuous glucose monitoring (CGM)25 and using an insulin pump instead of multiple daily injections26 can improve glycemic control and help avoid nocturnal hypoglycemia and hyperglycemia which can both interfere with sleep quality. Nocturnal hypoglycemia can disturb sleep among PwT1D and it can be difficult to fall back asleep after treating an episode of hypoglycemia.27 Low hypoglycemia awareness can place PwT1D at increased risk for severe life-threatening nocturnal hypoglycemia.28 Hyperglycemia can also affect sleep quality, given that it is associated with a lower overnight secretion of melatonin—an hormone regulating the sleep-wake cycle—and it can contribute to increase the need to urinate at night,27 disrupting sleep.

To our knowledge, large-scale studies specifically on PwT1D in Canada are scare. Our previous studies15, 16, 17 conducted among adults living with diabetes only included French-speaking adults from the province of Québec (Canada) and had <200 PwT1D. The objective of this study was to fill this gap in the literature by 1) verifying the proportion of PwT1D who have poor sleep quality; and 2) identifying the correlates of poor sleep quality using a large registry of English- and French-speaking PwT1D coming from different provinces in Canada. These results will help determine if many PwT1D in Canada have poor sleep quality and identify factors exposing them to poor sleep quality to determine which PwT1D should be prioritized and factors that can be targeted to possibly improve their sleep quality and prevent complications associated with poor sleep quality.