Final answer:
Older adults who had a persistently low or declining feelings of usefulness to others had an increased risk of earlier death.
Step-by-step explanation:
The statement mentioned in the question is supported by various research studies that highlight the importance of social connectedness and feelings of usefulness in older adults.
Researchers have found that older adults who have a persistently low or declining sense of usefulness to others are at an increased risk of earlier death.
For example, a study conducted in Alameda County, California, followed nearly 7,000 residents for 9 years and found that individuals with fewer social and community ties were more likely to die during the follow-up period compared to those with more extensive social networks, even after controlling for other health-related variables.