ICD-11 Prolonged Grief Disorder: Probable Prevalence and Structure in Bereaved Older Swiss Adults

Prolonged Grief Disorder (PGD) is a new diagnosis included in ICD-11. Research on ICD-11 PGD has often focused on spousal and parental loss, creating a gap in understanding the probable prevalence rates among older adults affected by diverse loss types. This study examines the prevalence of probable ICD-11 PGD, along with the symptom structure and convergent-divergent validity of the International Prolonged Grief Disorder Scale (IPGDS), in a sample of bereaved older adults. This study analysed data from a large sample (N = 1526) of German-speaking Swiss individuals aged 65 and older. Only those who reported a bereavement (n = 627) were included in the current analyses. Confirmatory factor analysis (CFA) tested the latent structure of the IPGDS, and the identified factors were examined in relation to a range of mental health variables. Probable prevalence rates of PGD ranged from 0.5% (strict criteria) to 1.0% (moderate criteria), with no significant gender differences. CFA supported a three-factor model, including Loss, Emotional Numbing, and Emotional Reactivity latent variables, with acceptable estimates of internal reliability. Total and subscale scores were most strongly associated with functional impairment scores, and associations were strongest between the Emotional Numbing subscale and all mental health variables. The findings indicate a lower than typical prevalence of probable PGD among Swiss older adults. Future studies should explore the role of loss-related characteristics in explaining the risk of PGD among older adults.