The DSM-5 describes personality disorders (PDs) as emerging in early life and remaining continuous throughout the life-span. Yet case studies and expert opinion support the existence of late-onset PDs. Little is known about PDs in late life, and our instruments for assessing them are not well validated. Thus, the focus of this exploratory Delphi study was the late-onset PD, with special attention to the accuracy of the core criteria for the diagnosis.

A Delphi study was designed to assess the presentation of PDs in late life. The Delphi consisted of three successive rounds of inquiry. Between rounds, the participants were provided with a summary of the panel’s responses.

A panel of 21 experts included published authors, researchers, and teachers from the USA, the UK, Australia, France, Belgium, and the Netherlands.

Researchers designed a survey that included an introduction, a demographic questionnaire, and five questions that varied in presentation and response format.

Experts reached consensus that a variant of PD appears de novo in old age. The core features of inflexibility and pervasiveness may not pertain to late-onset PD. There was agreement that frequently occurring life events contribute selectively to the expression of late-onset PD, with the major ones being death of a spouse or partner and transition to a nursing or assisted-living facility.

Nearly all participants took the position that PD can present for the first time in old age and be clinically identifiable without having been so identified earlier in life.