Insomnia with objective short sleep duration is associated with cognitive impairment: a first look at cardiometabolic contributors to brain health

Abstract

Study Objectives Insomnia with objective short sleep duration has been previously associated with adverse cardiometabolic health outcomes as well as poorer cognitive performance in otherwise noncognitively impaired adults. However, studies demonstrating an increased prevalence of cognitive impairment (CI) in this insomnia phenotype are lacking. Methods We analyzed data from Penn State Adult Cohort (N = 1,524; 48.9 ± 13.4 years; 53.4% women). Self-reported sleep difficulty was defined as normal sleep (n = 899), poor sleep (n = 453), and chronic insomnia (n = 172). Objective short sleep duration was defined as less than 6-h of sleep, based on in-lab, 8-h polysomnography. CI (n = 155) and possible vascular cognitive impairment (pVCI, n = 122) were ascertained using a comprehensive neuropsychological battery. Analyses adjusted for age, sex, race, education, body mass index, apnea/hypopnea index, smoking, alcohol, psychoactive medication, and mental and physical health problems. Results Participants who reported poor sleep or chronic insomnia and slept objectively less than 6 hours were associated with a 2-fold increased odds of CI (OR = 2.06, 95% confidence limits [CL] = 1.15–3.66 and OR = 2.18, 95% CL = 1.07–4.47, respectively) and of pVCI (OR = 1.94, 95% CL = 1.01–3.75 and OR = 2.33, 95% CL = 1.07–5.06, respectively). Participants who reported poor sleep or chronic insomnia and slept objectively more than 6 hours were not associated with increased odds of either CI (OR = 0.72, 95% CL = 0.30–1.76 and OR = 0.75, 95% CL = 0.21–2.71, respectively) or pVCI (OR = 1.08, 95% CL = 0.42–2.74 and OR = 0.76, 95% CL = 0.16–3.57, respectively). Conclusions Insomnia with objective short sleep duration is associated with an increased prevalence of CI, particularly as it relates to cardiometabolic health (i.e. pVCI). These data further support that this insomnia phenotype may be a more biologically severe form of the disorder associated with cardiovascular, cerebrovascular, and neurocognitive morbidity.

Sleep disturbance is associated with mild cognitive impairment: a community population-based cross-sectional study

“…This association between longer sleep duration and an increased risk of MCI was also observed in Hemodialysis patients and adults with metabolic syndrome [34,35]. However, some study shows short sleep duration is a risk factor for MCI [36,37], and there is a decreased risk of MCI for every additional hour of sleep among the elderly sleeping less than 7 h [38]. In this study, in order to more accurately evaluate the effect of actual sleep duration on cognitive impairment, different sleep duration was included in the regression analysis in turn, and after controlling for a variety of confounding factors, it was found that MCI may be more likely to occur if the sleep duration was more than eight hours.…”

Effect of Long-Term Benzodiazepines for Chronic Insomnia on Cognitive Function and Waking Electroencephalography: A Case-Control Study

“…Third, no information of objective or actual sleep time per night in all insomnia patients could limit the interpretation. The absolute sleep time may be more important to influence the decline of memory than subjective dissatisfaction of sleep [ 45 , 54 ]. Forth, there might be a selection bias among study participants.…”

Associations between Insomnia Symptoms and Anxiety Symptoms in Adults in a Community Sample of Southeastern Pennsylvania, USA

“…The distinctions matter because different manifestations of insomnia have disparate impacts; a study of Swedish workers, for instance, found that sleep onset insomnia was a stronger predictor of receiving disability than other nighttime disturbances [ 20 ]. The relationship between insomnia and anxiety is further complicated by sleep duration, as insomnia with short sleep is linked to greater neurocognitive impairment, more psychological distress, and ultimately more severe disease [ 21 , 22 , 23 , 24 ]. These findings raise the question of whether specific features of insomnia, in conjunction with sleep duration, have distinct implications for the severity or presentation of comorbid anxiety, as sleep continuity disturbances contribute to rising anxiety levels, and different combinations of insomnia symptoms correspond with different strengths of anxiety symptoms [ 25 ].…”