Multivariable regression (MVR) and one- (1SMR) and two-sample Mendelian randomization (2SMR) analyses indicate that frequent insomnia symptoms can cause higher hemoglobin A1c (HbA1c), according to a study published in the April issue of Diabetes Care.
Junxi Liu, Ph.D., from the University of Bristol in the United Kingdom, and colleagues examined the effects of five self-reported sleep traits (insomnia symptoms, sleep duration, daytime sleepiness, napping, and chronotype) on HbA1c in adults from the U.K. Biobank (336,999 participants) and in genome-wide association studies from the Meta-Analyses of Glucose and Insulin-Related Traits Consortium (46,368 participants) using MVR, 1SMR, and 2SMR.
The researchers found that a higher frequency of insomnia symptoms (usually versus sometimes or rarely/ever) was associated with higher HbA1c (standard deviation units: MVR, 0.05; 1SMR, 0.52; 2SMR, 0.24). After excluding participants with diabetes, the associations remained, but point estimates were somewhat attenuated. For other sleep methods, less consistency was seen across methods; some provided evidence of an effect.
…