Health briefs: Anemia raises risk for dementia; moon cycles weigh on sleep patterns

A study has found more evidence that anemia, a deficiency of red blood cells and a common condition in the elderly, raises the risk for dementia.

Researchers prospectively followed 2,552 mentally healthy men and women, average age 76, for 11 years, recording their red blood cell count and administering tests of mental functioning at regular intervals. At the start, 392 in the group were anemic, and by the end 455 had developed dementia. The study was published online in the journal Neurology.

After adjusting for age, sex, education, depression, diabetes and more than a dozen other variables, they found that those who were anemic at the start of the study had a 49 percent increased risk for dementia compared with those with normal blood counts.

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Swiss researchers have found evidence that the lunar cycle may affect sleep patterns. They found the connection by testing 33 healthy men and women, ages 20 to 74, in a sleep lab and correlating the data with the moon's phases. The study appears in the Aug. 5 issue of Current Biology.

Melatonin levels, total sleep time and delta sleep time (the deepest sleep, as recorded by EEG) reached their lowest levels at full moon and their highest as the moon waxed and waned. The average time it took to fall asleep and the time to arrive at REM sleep (the type of sleep in which dreams occur) followed the opposite pattern.

"Maybe there is a lunar clock in the brain, as found in other species like fish and other marine animals," said Christian Cajochen, of the University of Basel who led the study. "But we don't have direct evidence for that."

Well-established guidelines for the treatment of back pain require very conservative management — in most cases, no more than aspirin or acetaminophen and physical therapy. But a study published in JAMA Internal Medicine suggests that doctors are not following the guidelines.

Researchers studied 23,918 outpatient visits for back pain, a representative sample of an estimated 440 million visits made over 12 years in the United States. After controlling for factors such as age, sex, the nature of the pain, they found that during this time, Nsaid and Tylenol use fell more than 50 percent.

But prescriptions for opiates rose by 51 percent, and CT or MRI scans by 57 percent. Referrals to other physicians increased by 106 percent, which the authors said is a likely contributor to recent increases in expensive and often ineffective spine surgeries.