Multimorbidity and loneliness. Longitudinal analysis based on the GSOEP

Background: Our aim was to examine the longitudinal association between multimorbidity and loneliness in the general adult population (and in different age groups) in Germany.

Methods: Longitudinal data were used from the German Socio-Economic Panel (n= 44,385 observations in the years 2013 and 2017) - a nationally representative sample including adults aged 18 years and above. Respondents are re-surveyed annually. Loneliness was quantified using the established UCLA-3. Multimorbidity was defined as the coexistence of two or more conditions and was indicated by a list containing 13 somatic and mental diseases. Asymmetric linear fixed effects regressions (also stratified by three age groups: 18 to 44 years; 45 to 64 years, 65 years and older) were used to examine the association between the onset and end of multimorbidity as well as loneliness.

Results: After adjusting for possible confounders, regression analysis revealed that the onset of multimorbidity is associated with an increase in loneliness in the total sample (β = 0.07, p < 0.001) and among individuals aged 65 years and older (β = 0.13, p < 0.001), whereas no significant association was found in the other age groups. The end of multimorbidity was not associated with loneliness neither in the total group nor in the individual age groups.

Conclusion: This study revealed an association between the onset of multimorbidity and higher loneliness particularly among individuals in late life. Thus, preventing or delaying multimorbidity may be beneficial to avoid loneliness among older adults.