A study conducted by researchers at Ruppin Academic Center in Israel and Columbia University documents the broad impact on the mental health of Israelis, both Jews and Arabs, with sharp increases in post-traumatic stress disorder (PTSD), depression, and anxiety in the aftermath Hamas’ attack in October.

The study, published in the Lancet’s EClinicalMedicine  Jan. 5, 2023, found the prevalence of probable PTSD, depression, and anxiety in the weeks following the attacks (29% for PTSD, 42%-44% for depression and GAD, respectively), almost doubling the prevalence recorded two months before the attack.

“The prevalences of PTSD, depression, and anxiety are considerably higher than those reported in previous studies focusing on terrorist events, such as the 9/11 attacks and other attacks,” said Yossi Levi-Belz, PhD, a professor of clinical psychology and chair the Lior Tsfaty Center for Suicide and Mental Pain Studies at the Ruppin Academic Center in Israel who led the study.

The escalation of the longstanding Israeli-Palestinian conflict began Oct. 7 with Hamas’ attacks on civilians in Southern Israel that Israeli officials say killed more than 1,200 people and resulted in 240 being seized as hostages. The terrorist attack was followed by all-out war between the militant Palestinian group and Israeli forces, which followed more than a decade of relative calm across the Gaza-Israeli border.

The nationwide cohort study, according to the researchers, addressed limitations of previous research by using prospective study design to evaluate the impact of the attack. The researchers employed a wide range of probable outcome measures including PTSD, depression, and generalized anxiety disorder (GAD), assessing a cohort of Israeli citizens, both Jews and Arabs, twice, 6-7 weeks before the attack and 5-6 weeks after the attacks.

Since the beginning of the conflict 240,000 Israeli civilians have evacuated their homes and 129 Israelis are still held hostage.  The ground war in Gaza has also taken a heavy toll on Palestinians.  The health ministry in the Hamas-ruled Gaza Strip said that more than 20,000 people have been killed in the Palestinian territory since the beginning of the war.

Numerous studies have documented that traumatic events like war and armed conflicts can cause an alarming spike in post-traumatic stress and depression. Symptoms of PTSD were the most common health effect of the 9/11 attacks. Up to 20% of adults (link is external and opens in a new window)directly exposed to the disaster or injured in the attack had PTSD symptoms five to six years after the attack. Ten years after the attacks, 15% of the 70,000 enrollees in the World Trade Center Health Registry(link is external and opens in a new window) reported depression and 10% reported both depression and PTSD.

Study coauthor Yuval Neria, PhD, professor of clinical medical psychology (in psychiatry and epidemiology) at Columbia University Irving Medical Center and director of the PTSD Research and Treatment program at the New York State Psychiatric Institute (NYSPI), said the findings underline the crucial importance of conducting an immediate assessment of those exposed to severe trauma that taking into account pre-attack psychological difficulties and psychiatric ‘diagnoses’ in the aftermath of such a large-scale trauma.

“Moreover, nation leaders and policymakers should consider taking steps to allocates all resources to facilitate evidence-based treatments of affected civilians,” Dr. Neria added. “Early to mid-term interventions must be made accessible to citizens as a whole, with the aim of promoting self- and community efficacy, connectedness, and hope immediately after the attacks and during a massive military confrontation for both Israelis and Arab populations.”