Loneliness and Risk of Parkinson Disease. The risk is higher and independent of other risk factors

Seems pretty obvious!

Elvis Presley "Are you lonesome tonight" comes to mind.

"Key Points

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Findings  In this cohort study of 491 603 participants followed up for up to 15 years, loneliness was significantly associated with an increased risk of incident Parkinson disease independent of demographic and socioeconomic factors, social isolation, genetic risk, and physical and mental health. ...

Abstract

Importance  Loneliness is associated with morbidity and mortality, including higher risk of neurodegenerative diseases. To our knowledge, no study has examined whether the association between loneliness and detrimental outcomes extends to Parkinson disease (PD).

Objective  To assess whether loneliness is associated with risk of incident PD and whether the association is independent of other risk factors or modified by age, sex, and genetic vulnerability.

Design, Setting, and Participants  This prospective cohort study included a population-based sample of UK Biobank participants aged 38 to 73 years with loneliness data and without a diagnosis of PD at baseline who were first assessed from March 13, 2006, to October 1, 2010, and followed up to October 9, 2021.

Exposure  Feeling lonely and covariates that are known risk factors for or prodromal features of PD.

Main Outcome and Measure  Incident PD was ascertained through UK National Health Service health records.

Results  Of 491 603 participants (mean [SD] age, 56.54 [8.09] years; 54.4% female), 2822 developed PD during the 15-year follow-up. Individuals who reported being lonely had a higher risk of PD (hazard ratio [HR], 1.37; 95% CI, 1.25-1.51), an association that remained after accounting for demographic factors, socioeconomic status, social isolation, PD polygenetic risk score, smoking, physical activity, body mass index, diabetes, hypertension, stroke, myocardial infarction, depression, and ever seeing a psychiatrist (fully adjusted model: HR 1.25; 95% CI, 1.12-1.39). The association between loneliness and incident PD was not moderated by sex (HR for interaction, 0.98; 95% CI, 95% CI, 0.81-1.18), age (HR for interaction, 0.99; 95% CI, 0.98-1.01), or polygenic risk score (HR for interaction, 0.93; 95% CI, 0.85-1.02). Contrary to expectations for a prodromal syndrome, when stratified by time, loneliness was not associated with risk for incident PD during the first 5 years (HR, 1.15; 95% CI, 0.91-1.45) but was associated with PD risk during the subsequent 10 years (HR, 1.32; 95% CI, 1.19-1.46).

Conclusions and Relevance  This large cohort study found that loneliness was associated with risk of incident PD across demographic groups and independent of depression and other prominent risk factors and genetic risk. The findings add to the evidence that loneliness is a substantial psychosocial determinant of health."

Loneliness and Risk of Parkinson Disease | Movement Disorders | JAMA Neurology | JAMA Network (open access)

Credits: Johns Hopkins Bloomberg School of Public Health: Global Health NOW

Figure 1.  Cumulative Hazard of Parkinson Disease Among Participants Who Did and Did Not Report Loneliness at Baseline, Adjusted for Age and Sex.