Loneliness in older primary care patients and its relationship to physical and mental health-related quality of life

Background: Loneliness is a significant public health challenge in the United States, especially among older adults. The epidemiology of loneliness among older adults in primary care is lacking, and specific research is needed on how loneliness impacts older primary patients' physical, mental, and cognitive health. A large sample of older primary care patients were recruited for a trial during the COVID-19 pandemic to measure the relationship between loneliness and physical and mental quality of life (QOL). Methods: Baseline data come from the Caregiver Outcomes of Alzheimer's Disease Screening (COADS) study, an ongoing randomized controlled trial evaluating benefits and risks of Alzheimer's disease and related dementias screening among primary care patients ages 65 and older, collected April 2020 to September 2021. Loneliness was measured with the 5-item, Loneliness Fixed Form Ages 18+ from The NIH Toolbox Emotion Battery, physical and mental health-related QOL was measured with the SF-36v2, and depression and anxiety severity were measured with the PHQ-9 and GAD-7, respectively. Results: Spearman correlation analyses revealed that loneliness was moderately correlated with mental health QOL (r[601] = -0.43, p < 0.001), anxiety severity (r[601] = 0.44, p < 0.001), and depression severity (r[601] = 0.42, p < 0.001), while weakly correlated with physical health QOL (r[601] = -0.15, p < 0.001). After conducting unadjusted and adjusted linear regression models, we found that loneliness was significantly associated with both lower mental (p < 0.001) and physical (p < 0.001) QOL. Furthermore, loneliness remained significantly associated with worse mental QOL after adjusting for age, gender, race, ethnicity, educational level, perceived income status, neighborhood disadvantage, severity of comorbidities, and comorbid depression and anxiety. Conclusion; Primary care providers should discuss loneliness with their older adult patients and provide resources to help patients develop and maintain meaningful social relationships.