Post-traumatic stress (PTS) symptoms related to previous traumatic events are associated with more severe cancer-related PTS in Palestinian, but not Danish women with breast cancer

Aim: Having experienced previous traumatic events has been suggested to increase the risk of developing post-traumatic stress (PTS) symptoms followingtraumatic events later in life. We investigated the association betweenseverity of PTS-symptoms related to a previous non-cancer traumatic eventand the severity of breast cancer-related PTS-symptoms in two culturallydistinct samples.Methods: A total of 489 of 643 Palestinian women (mean age: 47.6 yrs)and 683 of 992 Danish women (mean age: 58.1 yrs) treated for breastcancer completed questions concerning ‘the most traumatic event other than cancer’ together with two versions of the Impact of Event Scale-Revised(IES-R) with reference to their cancer (CA-IES) and the other traumaticevent (OE-IES).Results: Palestinian women had higher CA-IES-scores (M = 39.85;SD = 13.7) than Danish women (M = 15.68; SD = 21.73; p <0.001). Atotal of 175 (38.8%) Palestinian and 86 (20.5%) Danish women reporteda non-cancer traumatic event before their diagnosis, with ‘war and combat’being the most frequent (34.3%) among Palestinians, and ‘death of a friendor loved one’ (38.4%) the most frequent among Danes. The OE-IES scoresrelated to these events were higher among Palestinian women (M = 41.3;SD = 12.6) than Danish (M = 17.9; SD = 17.4; p <0.001). Two hierarchicalmultiple regressions, adjusting for demographic and clinical variables,showed that for Palestinian women, OE-IES was a signifi cant predictor ofCA-IES (β = 0.54; p <0.001; CI(B): 0.48–0.71) together with older age,being married, having relapse, and tumorectory (p: 0.001–0.039). AmongDanish women, OE-IES did not predict CA-IES (β = −0.04; p = 0.76; CI(B):−0.24–1.78), and only the number of affected lymph nodes reached statisticalsignifi cance (β = 0.36; p <0.001; CI(B): 0.41–1.82).Conclusions: The severity of PTS-symptoms related to a previous noncancertraumatic event was a strong predictor of breast cancer-related PTSsymptomsin Palestinian women, but not in Danish women. Our fi ndingscould be explained by between-sample differences in life circumstances,including the types of non-cancer traumatic events.