Insomnia symptoms and risk of bloodstream infections: prospective data from the prospective population‐based Nord‐Trøndelag Health Study (HUNT), Norway

Abstract

Previous research suggests decreased immune function and increased risk of infections in individuals with insomnia. We examined the effect of insomnia symptoms on risk of bloodstream infections (BSIs) and BSI-related mortality in a population-based prospective study. A total of 53,536 participants in the second Norwegian Nord-Trøndelag Health Study (HUNT2) were linked to prospective data on clinically relevant BSIs until 2011. In Cox regression, we estimated hazard ratios (HRs) with 95% confidence intervals (CIs) for a first-time BSI and for BSI-related mortality (BSI registered ≤30 days prior to death) associated with insomnia symptoms. Compared with participants who reported "no symptoms", participants reporting having "difficulty initiating sleep" (DIS) often/almost every night had a HR for a first-time BSI of 1.14 (95% CI 0.96-1.34). Participants reporting "difficulties maintaining sleep" (DMS) often/almost every night had a HR of 1.19 (95% CI 1.01-1.40), whereas those having a feeling of "non-restorative sleep" once a week or more had a HR of 1.23 (95% CI 1.04-1.46). Participants frequently experiencing all three of the above symptoms had a HR of 1.39 (1.04-1.87), whilst those who had both DIS and DMS had a

Insomnia and risk of sepsis: A Mendelian randomization study

“…This is in line with previous research and results from observational data, reporting that insomnia increases the risk of altered immune response 3 and bloodstream infection. 5 We observed that large parts of the effect of genetically predicted insomnia on risk of sepsis were mediated through BMI, T2DM and smoking, which is in line with previous literature. 3,6,11,13 Although the precise mechanisms of this association remain elusive, evidence suggests that sleep can promote the immune homeostasis through different mediators that both affect the innate and adaptive immune responses.…”

“…It has recently been reported that people with symptoms of insomnia have an elevated risk of bloodstream infection (BSI)a condition closely linked to sepsis. 5 Sleep disturbances could be influenced by factors or conditions associated with the risk of infectious diseases (e.g., diabetes, cardiovascular disease, adiposity and smoking), 2,5 and the observed association between insomnia and infectious disease risk in previous studies may therefore be biased. Mendelian randomization (MR) is a powerful method using genetic variants as instruments for modifiable risk factors to reduce the influence of confounding and reverse causation.…”

“…It has recently been reported that people with symptoms of insomnia have an elevated risk of bloodstream infection (BSI) – a condition closely linked to sepsis. 5…”

Association of Genetically Predicted Insomnia With Risk of Sepsis

“…A recent observational study reported that insomnia increased the risk of bloodstream infection, a condition closely linked to sepsis . Importantly, since insomnia and systemic infections may share common causes, the observed association between insomnia and infectious disease risk could be biased due to residual confounding.…”

“…4 A recent observational study reported that insomnia increased the risk of bloodstream infection, a condition closely linked to sepsis. 5 Importantly, since insomnia and systemic infections may share common causes, the observed association between insomnia and infectious disease risk could be biased due to residual confounding. Mendelian randomization (MR) is a method that uses genetic variants as instruments for modifiable risk factors to reduce the influence of confounding and reverse causation.…”