BackgroundBurgeoning research suggests that people exposed to the 9/11/2001 terrorist attacks in New York City (NYC) may be at greater risk for cognitive impairment due to a variety of potential exposures. We investigated whether posttraumatic stress disorder (PTSD) history was associated with self-reported confusion or memory loss (CML) among World Trade Center Health Registry enrollees. MethodsThe study sample included enrollees who completed all five wave surveys (W1 in 2003–04 through W5 in 2020–21), were between the ages of 35 and 64 during W3-W5, and had no history of stroke or dementia (N = 11,432). We categorized PTSD history during W1-W3 as chronic-high, increased, decreased, or resilient-low with trajectory analysis. Generalized estimating equations modeling was used for the repeated measures analysis of the outcome, CML. ResultsCompared to those in the resilient-low PTSD group, those in the decreased and increased PTSD groups were at over 52% greater risk of reporting CML; those in the chronic-high PTSD group had between a 1.62 and 1.92 times greater risk of CML than the resilient-low PTSD group, with non-rescue/recovery workers having greater risk on average. PTSD history was also associated with elevated risk of more severe CML-related outcomes in W5 – specifically, experiencing worsening symptoms and functioning in daily life. LimitationsCML symptoms are self-reported, and generalizability of results may be limited. ConclusionsThese findings suggest that survivors with PTSD should be monitored for cognitive issues, including CML. Effective treatment of PTSD may have benefits beyond mitigation of PTSD symptoms.