NOVEL findings showed a significant association between irregular sleep duration and the risk of developing diabetes, highlighting the potential metabolic consequences of sleep variability.
The study involved 84,421 participants with a mean age of 62, all free of diabetes at the start and who provided accelerometer data between 2013 and 2015. Data was collected from the UK Biobank. The accelerometer, similar to a fitness watch, measured the participants’ sleep duration over seven days. Researchers quantified sleep duration variability using the within-person standard deviation (SD) of these nightly measurements.
Over the follow-up period, 2,058 participants developed diabetes. The analysis revealed a clear pattern: as sleep duration variability increased, so did the risk of diabetes. Participants with a sleep duration SD of 31 to 45 minutes had a 15% higher risk of developing diabetes compared to those with a variability of 30 minutes or less. This risk escalated to 59% for those with a sleep duration SD of 91 minutes or more, after adjusting for age, sex, and race.
The researchers further explored the impact of sleep duration variability of over 60 minutes compared to 60 minutes or less. They found a 34% increased risk of diabetes for those with higher variability. However, this association weakened to 11% after accounting for lifestyle factors, comorbidities, environmental influences, and adiposity.
The study also examined genetic factors, using polygenic risk scores (PRS) for diabetes derived from known genetic risk variants. Interestingly, the link between sleep duration variability and diabetes risk was more pronounced in individuals with lower PRS and longer average sleep duration.
Despite its robust findings, the study had limitations. The cohort was predominantly white (97%) and well-educated (over 45% had a college degree), which may not represent the broader UK population. Moreover, the study did not delve into the underlying mechanisms driving the observed association. However, the authors speculated that irregular sleep patterns might disrupt circadian rhythms, thereby affecting glucose metabolism and insulin sensitivity. Researchers concluded that the study underscores the importance of consistent sleep patterns in mitigating diabetes risk. Further research is needed to understand the precise mechanisms and to confirm these findings in more diverse populations.
Laith Gergi, EMJ
Reference:
Kianersi S et al. Association between accelerometer-measured irregular sleep duration and type 2 diabetes risk: a prospective cohort study in the UK biobank. Diabetes Care. 2024;dc240213.