Lower Immunity Linked to Stress From ’94 Quake

NORTHRIDGE — A UCLA Medical School study of 68 employees of a San Fernando Valley hospital badly damaged by the Northridge earthquake concluded that the stress of the disaster weakened their immune systems and continued to do so for months afterward.

The study--to be published in the April issue of the medical journal Psychosomatic Medicine--was performed by university staff on employees of the Sepulveda Veterans Administration Medical Center, said Dr. George Solomon, the professor emeritus of psychiatry and biobehavioral sciences at UCLA who headed the study.

“This research shows that natural disasters . . . not only cause emotional distress but they also can create negative physical effects,” Solomon said.

He said the idea for the study occurred to him after he personally experienced the temblor’s stress.

“When the earthquake destroyed my office and I was totally stressed out, it seemed like the right thing to study,” Solomon said.

The employees’ immune systems were examined for four months beginning 11 days after the Jan. 17, 1994, quake, he said.

The subjects covered wide socioeconomic and ethnic ranges--from janitors to doctors of the hospital who shared the common stress of badly damaged homes and the possibility of losing their jobs as the hospital threatened to close, Solomon said. About a third of the subjects also suffered injuries or had a friend or relative hurt by the quake.

Blood samples were taken periodically from the employees and examined for the number and function of two types of cells: the “natural killer cell,” which responds first to combat disease, and several types of T cells, which help the body fight off disease-causing bacteria and other causes of illnesses, according to the study.

The study’s primary finding was that even as anguish over the disaster diminished, the major components of the immune system continued to be suppressed by low cell counts.

Though formal studies have not been performed, it has been conventional wisdom that a high degree of stress can suppress the immune system, Solomon said. But his team’s findings indicate that the system continues declining even as anxiety and confusion slowly diminish.

“We are not built biologically for prolonged emotional distress,” Solomon said.

The team could not determine for how long the subjects’ immune systems continued to be depressed because the study stopped after four months, Solomon said. But there have been studies after other traumatic events that have shown individuals’ systems remain weak for as long as a year.

And although his subjects generally did have high illness rates--with afflictions such as the flu--their illnesses could not be corollated to their suppressed immune systems, Solomon said.

The findings can help victims of future natural disasters by demonstrating that they should take measures in the aftermath of an event to relieve stress--such as by obtaining therapy or other professional psychological help.

“Interventions that can ease the distress or help people express their emotions may have a positive effect on the immune system--as well as on their psychological well-being,” Solomon said.