Cross‐Sectional Associations Among Sleep Quality, Hippocampal Volume, and Memory Complaints in the Offspring Study

Abstract

AbstractBackgroundPoor sleep quality, a modifiable risk factor for dementia, that is prevalent in non‐Hispanic Black and Hispanic adults, is associated with greater memory complaints and smaller hippocampal volumes in predominantly non‐Hispanic White samples. These associations among sleep quality, memory complaints, and hippocampal volumes are understudied in non‐Hispanic Black and Hispanic adults—populations disproportionately affected by poor sleep quality and cognitive performance. The objective of the current study was to examine associations among sleep quality, memory complaints, and hippocampal volumes in a racially and ethnically diverse, community‐based sample. Given sociocultural and environmental differences that affect sleep, brain measures, and cognitive performance, we hypothesize that poorer sleep quality is associated with more memory complaints and smaller hippocampal volumes, especially in Black and Hispanic adults.MethodParticipants included Black, Hispanic, and White adults from the Northern Manhattan community (n = 1175; 56±11 years; 67% women; 14±3 years of education; 17% Non‐Hispanic White; 20% Non‐Hispanic Black; 63% Hispanic). Participants self‐reported their sleep quality with the 9‐item Pittsburgh Sleep Quality Index, which measures average sleep disturbance over the past month. Participants self‐reported experiences with forgetting (e.g., names, faces, directions) with an abbreviated version of the Memory Functioning Questionnaire. In a subsample of participants, hippocampal volumes were measured on T1‐weighted MRI scans with FreeSurfer software. Sleep quality, hippocampal volume, and memory complaints were treated as continuous variables. We ran multivariable regression analyses adjusted for age, education, gender identity, depression severity, and intracranial volume for analyses with hippocampal volume.ResultAcross racial and ethnic groups, poorer sleep quality was associated with more memory complaints (n = 1175, B = ‐0.31, CI: [‐41,‐.22]). These associations were similar when analyses were stratified by racial and ethnic group. Among Hispanic adults, there was a trending association between poorer sleep quality and smaller left hippocampal volumes (n = 246, B = ‐8.94, CI: [‐18.75,0.88]).ConclusionPoorer sleep quality was associated with more memory complaints across racial and ethnic groups and showed a trending association with smaller hippocampal volumes in Hispanic adults. Future studies with larger samples should replicate these findings with longitudinal data to quantify the temporal relationship of sleep quality with memory complaints and structural brain changes.