Functional limitations and loneliness in middle-aged and older adults: differentiating emotional loneliness and social loneliness

Abstract Background People with functional limitations may be lonelier than those without functional limitations, as health-related constraints can restrict social participation. However, this relationship might also vary depending on the type of loneliness considered and the age of the individual. Consequently, this study examines differences in emotional and social loneliness according to functional limitation status and across age groups. Methods Population-based data from 3,984 participants aged 40 and older from the 2023 German Aging Survey were analyzed. Emotional and social loneliness were measured using the De Jong Gierveld Loneliness Scale, and functional limitations were assessed using the Global Activity Limitation Indicator (GALI). Analysis of variance examined differences across age groups and functional limitation severity. Results Results showed that participants with functional limitations generally reported progressively higher levels of both types of loneliness compared to those without functional limitations. Emotional loneliness showed consistent patterns across age groups, with progressive increases from no functional limitations to moderate functional limitations to severe functional limitations. In contrast, social loneliness displayed a significant interaction with age group, where middle-aged adults (40–65 years) showed much stronger progressions in social loneliness according to functional limitation severity as compared to older adults (66+). Conclusions These findings suggest that functional limitations are generally associated with increased loneliness, but that the extent varies by both type of loneliness and age group. The stronger differences in social loneliness among middle-aged adults indicate that functional limitations may have particularly pronounced social implications earlier in the life course. Middle-aged adults with functional limitations thus represent a particularly psychosocially vulnerable group.