Borderline personality disorder in four different age groups: a cross-sectional study of community residents in Germany.

Studies examining the natural course of borderline personality disorder (BPD) over the life span have yielded declining prevalence rates in older age groups. However, there is evidence that different BPD symptoms have different longitudinal patterns, with impulsivity decreasing with advancing age and negative affect remaining stable into late adulthood. However, since all studies dealt with treated, clinical samples of BPD patients, it is not yet known whether this represents the natural course of BPD symptoms or just mirrors difference in treatability of these symptoms. The authors addressed this issue by investigating a nonclinical population and compared prevalence of BPD, impulsivity, and depressivity in various age groups from adolescence to late adulthood (N = 2,488); all individuals were assessed by standardized clinical interviews. Syndromal and subsyndromal BPD rates sharply decreased between adolescents and young adults and remained stable thereafter. Whereas the same course was found for impulsivity, depressivity increased between young, middle-aged, and older adults. The present results support the hypothesis that age-related decreases in BPD diagnosis might be attributable to declining levels of impulsivity, whereas the persistence of a subsyndromal BPD might be attributable to an enduring negative affect.