Social connections are differentially related to subjective age and physiological age acceleration amongst older adults.

Living alone was associated with accelerated physiological age in older adults.

• Data from 7047 adults aged 50+ in the English Longitudinal Study of Ageing (ELSA) were used.
• Doubly robust estimations using inverse-probability-weighted regression adjustment (IPWRA) estimators were employed.
• Living alone was identified as a risk factor for physiological age acceleration.
• Associations were robust to multiple sensitivity analyses and maintained four years later.

Low social integration was associated with accelerated physiological age in older adults.

• Social connections were characterized across structural, functional, and quality components.
• Low social integration was identified as a risk factor for physiological age acceleration.
• IPWRA estimators were used to provide doubly robust estimations.
• The association was maintained at four-year follow-up.

Low social support was associated with accelerated physiological age in older adults.

• Low social support was identified as a risk factor for physiological age acceleration.
• The physiological ageing measure was a validated composite combining cardiovascular, respiratory, haematologic, and metabolic indicators.
• Analyses were robust to multiple sensitivity analyses.
• Results were maintained four years later.

Weak social connections did not have a statistically significant association with older subjective age.

• Subjective age was assessed alongside physiological age as an outcome measure.
• None of the social connection components (structural, functional, or quality) showed statistically significant associations with older subjective age.
• This finding differentiates the pathways through which social connections relate to ageing outcomes.
• The sample included 7047 adults aged 50+ from ELSA.

The study used a validated physiological ageing measure combining multiple biological system indicators.

• The physiological ageing measure combined cardiovascular, respiratory, haematologic, and metabolic indicators.
• The measure was described as a 'validated physiological ageing' score.
• The sample consisted of 7047 adults aged 50+ from the English Longitudinal Study of Ageing.
• Both subjective age and physiological age acceleration were examined as outcomes.

The authors propose that accelerated physiological ageing may be a mechanism underpinning the relationship between weak social connections and age-related morbidity and mortality.

• This hypothesis is presented based on the finding that social connections relate to physiological but not subjective age.
• The proposed mechanism involves accelerated physiological ageing as an intermediary pathway.
• Weak social connections have previously been associated with adverse age-related health outcomes.
• The authors characterize human social connections as 'complex ecosystems formed of structural, functional and quality components.'