ISLAMABAD  – Dietary supplements enriched in omega-3 fatty acids, a component of fish oil, may help cancer patients gain weight, new research suggests.

Weight loss and muscle deterioration are common problems for people with advanced cancer. In animal studies, omega-3 fatty acids have been shown to protect against this problem, also known as cachexia.

The current findings, reported in the medical journal Gut, are based on a study of 200 patients with pancreatic cancer who received a diet supplement containing omega-3 fatty acids or a similar supplement lacking these fatty acids for 8 weeks. The subjects were instructed to consume two cans per day of the assigned supplement.

In the overall analysis, both supplements were equally effective in stopping the loss of body weight and muscle tissue, Dr. K. C. H. Fearon, from the Royal Infirmary of Edinburgh in the UK, and colleagues report.

However, on average, patients only consumed 1.4 cans per day of supplement—well below the recommended dose of 2 cans per day.

When the data was reanalyzed taking this into account, the authors found that as the amount of the omega-3 supplement consumed went up, so did weight and muscle gain. In contrast, this effect was not seen with the supplement lacking omega-3 fatty acids.

The team also found that only weight gain with the omega-3 supplement was actually tied to an improved quality of life. Because many patients did not take the recommended daily amount of supplements, “further trials are required to examine the potential role of omega-3 enriched supplements in the treatment of cancer cachexia,” the investigators conclude.

New clues for sciatica pain relief

For years, damaged discs in the lower back or spinal nerve problems have taken the blame as the most common cause of sciatica, a painful condition in which the sciatic nerve in the back of the leg is pinched and pain radiates down the leg.

But a new study suggests the cause of sciatica pain may actually be piriformis syndrome, a condition in which a muscle in the buttocks called the piriformis compresses or irritates the sciatic nerve.

The findings may help many patients finally get relief from their pain, said study author Dr. Aaron Filler, a neurosurgeon at Cedars-Sinai Institute of Spinal Disorders in Los Angeles. “Doctors often recommend spinal fusion surgery for spinal problems [associated with sciatica],” he said, “when the real problem is piriformis syndrome.”

In the study, Filler and his colleagues evaluated 239 patients whose symptoms of sciatica had not improved after diagnosis or treatment for a damaged disc.

They performed the usual X-rays and MRI scans, and found seven of the patients had torn disc-related conditions that could be treated successfully with spine surgery.

The other 232 patients underwent MR neurography, a new technique that generates detailed images of nerves. The researchers report that 69 percent had piriformis syndrome, while the other 31 percent had some other nerve, joint or muscle condition.

To treat piriformis syndrome, Filler’s team injected a long-acting anesthetic into the spine, muscle or nerve areas. About 85 percent of the patients got some relief from the injections, which helps relax muscle spasm.

However, relief was not long-lasting and 62 patients needed surgery to correct the syndrome. Of those, 82 percent had a good or excellent result during the six-year follow-up.

The findings may help legions of Americans suffering from sciatica, Filler said. “More than 1.5 million Americans have experienced sciatica severe enough to be sent for lumbar MRI scanning each year,” Filler said. “About 300,000 lumbar disc surgeries are done each year for sciatica. Of those, about one-third fail.”

In some cases, those surgeries may fail because disc damage is not the underlying problem, Filler said. Instead, the real culprit could be other conditions, such as piriformis syndrome.

The nerve scan used in the study is relatively new, Filler said, being first used in humans in 1993. His group reported on the first groups of patients who underwent the technique in 1996. “Since 1996, we have imaged several thousand patients,” he said. The technique is available now at major universities and hospitals, Filler said, and is expected to become more widespread in the next year or so.

While the study provides new clues to sciatica, experts say its results need to be duplicated. When patients complain of sciatica, “we typically focus on spinal nerves,” explained Dr. Scott M. Fishman, president-elect of the American Academy of Pain Medicine.

“This study helps clarify that pain that radiates down the back of the leg is often of sciatic origin,” Fishman said, and doctors should consider the possibility that the pain may be due to entrapment of the sciatic nerve by the piriformis muscle.

“Piriformis syndrome is pooh-poohed [as a diagnosis] by orthopedic surgeons and neurosurgeons,” added Dr. Peter Slabaugh, a spokesman for the American Academy of Orthopaedic Surgeons. But the new findings, he said, “might have some merit,” although he said more studies with similar results are crucial before firm recommendations can be made.

Those with sciatica should also know that the pain typically comes and goes, Slabaugh said. Unless symptoms are very severe, waiting three months after the pain starts before undergoing serious treatments such as surgery is usually sound advice, he added.

If the pain doesn’t subside after three months, patients would be wise to then consider imaging studies of the spine and nerves, he added.

Older male smokers be screened for abdominal aneurysm 

Former or current male smokers between 65 and 75 years old should receive an ultrasound screening for abdominal aortic aneurysm, recommends the U.S. Preventive Services Task Force.

Abdominal aortic aneurysm, which kills more than 9,000 Americans each year, is an abnormal ballooning within the abdomen of the aorta, the major artery that runs from the heart. Experts estimate that between 59 percent to 83 percent of patients experiencing this type of aneurysm die before reaching the hospital.

The task force noted that close to 70 percent of men between 65 and 75 years of age have been smokers at some point in their lives and would benefit from an ultrasound screening for abdominal aortic aneurysm. This is the first time the task force has made such a recommendation, which appears in the Feb. 1 issue of the Annals of Internal Medicine.

Older men who are current or former smokers have the highest risk for abdominal aortic aneurysm, and screening and surgery to repair these aneurysms can reduce the number of deaths caused by this condition, the task force concluded.

It made no recommendation about screening for men who’ve never smoked and found no evidence of benefit from screening of women.

“This is an important recommendation because evidence now exists that screening high-risk men for abdominal aortic aneurysms can reduce deaths from aneurysm,” Task Force chairman Dr. Ned Calonge, chief medical officer and state epidemiologist with the Colorado Department of Public Health and Environment, said in a prepared statement.

“One of the most important things men and women can do for their health is to never start smoking and to quit if they do. People who have a family history and might be at risk for abdominal aortic aneurysm should discuss their concerns with their physician,” Calonge said.