Insomnia and falls in older adults: are they linked to executive dysfunction?

BACKGROUND: Insomnia increases the incidence of falls and impairs executive function. Moreover, falls are associated with executive function impairment. The relationship between falls and executive function in patients with insomnia is not clear. The aim of this study was to evaluate relationship between falls and executive function in individuals with insomnia and a control group. METHODS: This study involved 122 patients (47 insomnia, 75 controls). The Mini-Mental State Examination, Quick Mild Cognitive Impairment Screen, Trail Making Test A, clock-drawing test, and digit span test were used to measure executive function. Semantic and working memory dual task was also performed. Fall history was recorded and the Falls Efficacy Scale - International administered. RESULTS: The median age of the patients was 71 years (range: 65-89 years), and 60.7% were women. The insomnia group scored lower on the three-word recall than the control group (P = 0.005), but there was no difference between the groups on cognitive tests. Fall history and fear of falling were more frequent in the insomnia group (P = 0.003, P < 0.001). Semantic and working memory dual tasks were correlated with clock-drawing test only in the insomnia group (r = -0.316, P = 0.031; r = -0.319, P = 0.029). Depression (odds ratio (OR) = 9.65, P = 0.001) and Trail Making Test A (OR = 1.025, P = 0.07) were independently associated with insomnia. Four-metre walking speed (OR = 2.342, P = 0.025), insomnia (OR = 3.453; P = 0.028), and the semantic memory dual task (OR = 1.589; P = 0.025) were also independently associated with falls. CONCLUSION: Our study showed that dual tasking and executive function are related to falls in patients with insomnia. Managing insomnia and assessment of executive dysfunction may have beneficial effects on preventing falls.