A recently published NorLAG paper examines trends and predictors in self-esteem in the second half of life (age 40+). Findings show increasing self-esteem among men and women until late midlife.
A strong decline is however observed from mid-70s, explained by age-related changes in roles, health, and social relationships.
Tilmann von Soest, Thomas Hansen et al: Self-Esteem Across the Second Half of Life: The Role of Socioeconomic Status, Physical Health, Social Relationships, and Personality Factors. Journal of Personality and Social Psychology. 2017. DOI: 10.1037/pspp0000123. Abstract.