Johns Hopkins researchers have found ‘dramatic’ results in small preliminary study carried out in the Cayman Islands.

A small group of veterans with spinal cord injuries who underwent a four-day scuba- diving certification with local dive operation Red Sail, saw significant improvement in muscle movement, increased sensitivity to light touch and pinprick on the legs, and large reductions in post-traumatic stress disorder (PTSD) symptoms, according to Johns Hopkins researchers.

The researchers, while calling the advances made over the course of a few days “dramatic,” caution that the results are preliminary, the study size small and the duration of the benefits are unknown.

Still, they say, the findings suggest there may be a pathway for restoring neurological and psychological function in paraplegics that has been overlooked thus far.

“There is no treatment for people with chronic spinal cord injury and many believe once you’ve lost the communication between the brain and the extremities, there is nothing you can do to restore lost function,” says  Adam Kaplin, M.D., Ph.D., an assistant professor of psychiatry and behavioral services at the Johns Hopkins University School of Medicine.

“What we saw in the water strongly suggests there is some scuba-facilitated restoration of neurological and psychological function in paraplegics. It’s very provocative.”

Kaplin, who will present the findings at the Paralyzed Veterans of America conference on Sept. 17 in Orlando, emphasises that his team cannot “establish beyond a shadow of a doubt that what we saw is reproducible or durable.” Nor could he explain how the scuba effects may have worked.

Kaplin and Becker collected their data in the Cayman Islands in May during a scuba certification trip for disabled veterans.

Before the dives, Kaplin and Becker conducted a series of neurological and psychological tests on all 19 subjects. Then the participants underwent scuba certification, which included a series of nine dives over the course of four days. Eight of the 10 paraplegics ultimately completed the dives.

“We saw dramatic changes in a matter of days in a number of people with spinal cord injury who went scuba diving,” Becker says. “This is just a pilot study, but to see such a restoration of neurological function and significant improvement in PTSD symptoms over such a short period of time was unprecedented.”

The researchers saw an average 15 percent reduction in muscle spasticity in those disabled veterans who went diving and an average 10 percent increase in sensitivity to light touch and five percent to pinprick. In some individuals the improvement in tone, sensation or motor function was between 20 and 30 percent. The healthy controls experienced no neurologic changes.

The researchers also found an average decrease of 15 percent in obsessive compulsive disorder symptoms in the disabled divers, a similar decrease in signs of depression, and an overall decrease in mental problems using a validated psychological assessment.

Kaplin concedes those improvements may have been influenced by the fact that the subjects were taken on a Caribbean vacation and got to go diving on a beautiful reef. But the most striking psychological impact was seen in PTSD symptoms, which decreased, on average, by 80 percent in those veterans who went diving. Escaping to a tranquil beach setting, Kaplin says, wouldn’t be enough to account for such an apparent escape from PTSD symptoms.

The researchers say they don’t really know how to explain the effect scuba diving may be having on the bodies of those with spinal cord injuries. Kaplin says it is possible that weightlessness in the water may play a role in improvements found in paraplegic veterans.

The researchers would like to do a follow-up study, which would compare results after scuba, snorkeling and time spent in a hyperbaric chamber simulating underwater dives. These may be able to tease out what role may be played by exercise and what role may be played by air pressure.

“Is there something healing happening under there?” Becker asks. “There’s a signal but only by repeating these results and showing significant improvements can we establish that. It’s too early to know for sure.