Association Between Non-Iron-Deficient Anemia and Insomnia Symptoms in Community-Dwelling Older Adults: The Baltimore Longitudinal Study of Aging.
Anemia is associated with poorer sleep in children, and clinically, anemia is linked to insomnia. However, the association between anemia and insomnia in older adults is understudied.



We examined the cross-sectional association between anemia and insomnia in 1,053 adults (71.4 ± 10.6 years) in the Baltimore Longitudinal Study of Aging. Participants were classified as nonanemic, non-iron-deficient anemic, or iron-deficient anemic based on hemoglobin, ferritin, transferrin saturation, and mean cell volume. Insomnia symptoms were evaluated by the Women's Health Initiative Insomnia Rating Scale (WHIIRS). A total score (range 0-20) was generated, and participants were also classified as having 0, 1, or 2+ symptoms.



Overall, 10.5% of participants had non-iron-deficient anemia, 0.9% had iron-deficient anemia, and 88.5% had no anemia. Due to its low prevalence, the iron-deficient anemic group was dropped from analyses. In models adjusted for demographics, number of medical conditions, and Center for Epidemiologic Studies Depression Scale score, non-iron-deficient anemic individuals had significantly higher WHIIRS total scores, indicating greater insomnia severity, compared to those without anemia (predicted adjusted mean WHIIRS of 7.24 [95% confidence interval (CI): 6.40-8.08] vs 5.92 [95% CI: 5.65-6.19]). They also had twice the risk of reporting ≥2 insomnia symptoms (vs 0 symptoms; relative risk ratio = 2.20, 95% CI: 1.25-3.89).



Results suggest that individuals with non-iron-deficient anemia are more likely to experience insomnia symptoms than those who are nonanemic. These results may have implications for insomnia treatment or the identification of underlying frailty in individuals with sleep problems.
School of Health and Applied Human Sciences, University of North Carolina Wilmington.
Lenis P
LP
Chen-Edinboro
Department of Nutritional Sciences, The Pennsylvania State University, University Park.
Laura E
LE
Murray-Kolb
Intramural Research Program, National Institute on Aging, Baltimore, Maryland.
Eleanor M
EM
Simonsick
Intramural Research Program, National Institute on Aging, Baltimore, Maryland.
Luigi
L
Ferrucci
Department of Neurology, Johns Hopkins University, Baltimore, Maryland.
Richard
R
Allen
Office of Research Development, Duke University School of Medicine, Durham, North Carolina.
Martha E
ME
Payne
Department of Mental Health, Johns Hopkins University, Baltimore, Maryland.|Department of Psychiatry and Behavioral Sciences, Johns Hopkins University, Baltimore, Maryland.
Adam P
AP
Spira
D000368:Aged; D000369:Aged, 80 and over; D000740:Anemia / Q000453:epidemiology*; D015142:Baltimore / Q000453:epidemiology; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D057187:Independent Living; D008137:Longitudinal Studies; D008297:Male; D015995:Prevalence; D007319:Sleep Initiation and Maintenance Disorders / Q000453:epidemiology*