It wouldn't surprise me if healthy, privileged people with access to good healthcare are more optimistic than those with serious illness, no coverage and three shitty jobs.

Hard to be optimistic when you have cancer and can't afford treatment.

> These relations were independent of socioeconomic status, health conditions, depression, social integration, and health behaviors (e.g., smoking, diet, and alcohol use). Overall, findings suggest optimism may be an important psychosocial resource for extending life span in older adults.

Yeah I also feel introducing some social class - income level variable would help clear things up.