Study finds prolonged grief disorder can follow the death of a pet

A nationally sampled survey of UK adults reports that a measurable minority of people who lose a beloved pet meet symptom criteria consistent with prolonged grief disorder (PGD), and that the symptom structure of PGD does not differ when respondents report on pet vs human losses. The paper, published January 14, 2026, provides conditional rates, relative risk estimates, and measurement invariance testing that the author says raises questions about current diagnostic rules that restrict PGD to human bereavement.1

National sample, online panel

Study author Philip Hyland analyzed responses from 975 UK adults recruited via Qualtrics between March 1 and March 27, 2024. The sample was quota-constructed to approximate the UK population by sex, age, nation (England, Wales, Scotland, Northern Ireland), and income band. Participants completed the International Grief Questionnaire—Clinical Version (IGQ-CC) and reported their bereavement histories and which loss they considered most distressing. Standard online panel quality controls (attention checks, duplicate IP screening, CAPTCHA, and response pattern filters) were applied, and study materials are available on the Open Science Framework.1

Key results

Approximately one-third of respondents (32.6%, n = 318) reported having experienced the death of a beloved pet. Eighty-four percent of the sample (n = 821) reported at least 1 bereavement of any kind, and among respondents who had lost both a person and a pet, 21.0% (n = 62) nominated the pet loss as their most distressing bereavement.1

Across the full sample, 8.6% (n = 84) met International Classification of Diseases, 11th Revision criteria for PGD, as operationalized in the survey. The conditional rate of PGD following pet bereavement was 7.5%. Hyland reports that this figure was similar to conditional rates observed for several common human bereavement types in the same data set. The calculated relative risk for pet bereavement was 1.27, indicating that participants who had experienced pet loss were 27% more likely to meet PGD criteria than those who had not. The study’s population attributable risk percentage for pet loss was 8.1%, a metric that combines the prevalence of exposure and its association with PGD to estimate the proportion of cases in the sample attributable to that exposure.1

Do PGD symptoms differ by type of loss?

Hyland used confirmatory factor analysis and sequential measurement invariance testing across a 2-factor model (core and associated symptoms) to examine whether the latent structure of PGD differed when respondents reported symptoms tied to a pet vs a person. Fit indices supported the 2-factor representation, and the tests indicated configural, metric, and scalar invariance between pet-bereaved and human-bereaved groups. The author interprets these results as evidence that PGD symptoms operate equivalently across pet and human losses in this sample.1

Limitations noted by the author

Hyland explicitly lists several limitations. The study used quota sampling from a nonprobability online panel, which limits generalizability despite demographic quotas and quality checks. Symptom assessment relied on self-report via the IGQ-CC rather than structured clinical interviews, and the IGQ-CC had not previously been applied in a pet bereavement context. The analysis did not model the cause of death or euthanasia effects, factors that the author acknowledges can influence grief outcomes. Finally, cultural differences in pet ownership and bereavement norms limit the ability to generalize findings beyond the sampled UK population.1

Author conclusions and recommended next steps

As stated in the paper, the author concludes that people can experience clinically relevant levels of PGD following the death of a pet and that PGD symptoms show the same underlying structure regardless of whether the loss is human or animal. The paper raises questions about the exclusion of pet bereavement from current PGD diagnostic definitions and calls for replication, investigation of cause-of-death effects (including euthanasia), and cross-cultural research to clarify these findings.1

Reference

Hyland P. No pets allowed: evidence that prolonged grief disorder can occur following the death of a pet. PLoS One. 2026;21(1):e0339213. doi:10.1371/journal.pone.0339213