Year of Publication


Degree Name

Master of Science (MS)

Document Type

Master's Thesis


Arts and Sciences



First Advisor

Dr. Suzanne C. Segerstrom


Amyotrophic Lateral Sclerosis (ALS) is a progressive neurodegenerative disease. Despite the debilitating nature of this disease, some evidence suggests patients maintain their quality of life (QOL). Caregivers, on the other hand, experience decreased QOL. Evidence suggests existential aspects of well-being such as purpose in life (PIL) may be unique and stable sources of well-being for patients and caregivers. Furthermore, patients’ and caregivers’ well-being may impact one another. The present study examined the variance structure, trajectory, and dyadic relationship of PIL and QOL in patients with ALS and their caregivers (N = 110 dyads). Data from the Seattle ALS Patient Profile Project were utilized; PIL and QOL were assessed seven times, over eighteen months. PIL was more stable than QOL and therefore a psychological resource for patients and caregivers. PIL and QOL declined with time and disease severity. Individual differences in proximity to diagnosis and death moderated within-individual change. Decline was more rapid following diagnosis and approaching death, suggesting these are critical periods in which individuals need increased support. Well-being within the dyad was interrelated. Average QOL was similar across dyads. PIL within the dyad changed together over time. Dyadic relationships may reflect similar life conditions and a shared disease experience.