Study Sees No Link Between Water Fluoridation and Bone Loss
Fluoridation of water does not increase the risk of osteoporosis, as some critics have charged, according to British researchers. Fluoridation is known to be beneficial in preventing tooth decay, but some researchers believe it accelerates bone loss. Previous studies have given mixed results.
Dr. David Coggon and his colleagues at the University of Southampton studied 514 hip fracture patients in the English county of Cleveland, where water is fluoridated in some communities and not in others, and compared them to 527 control subjects without hip fractures. Hip fractures are a common sign of osteoporosis.
The team reported in Saturday’s Lancet that accounting for all other variables, there was no increased risk of hip fractures among those who drank fluoridated water.
Value of Tests Before Surgery Questioned
Routine preoperative blood tests and electrocardiograms given before cataract surgery cost Medicare nearly $150 million a year but do not necessarily make the surgery any safer for patients, according to researchers from Johns Hopkins University in Baltimore. Such tests, which amount to a systematic medical examination of overall health, should be done only if a patient’s medical history or physical examination suggests the need--such as when a patient has not received medical care for many years.
Dr. Oliver D. Schein and his colleagues randomly assigned 19,250 cataract surgery patients to either receive conventional pre-op testing or testing only if their physicians saw a new medical problem or an ailment that was getting worse. They reported in Thursday’s New England Journal of Medicine that each group had about 31 complications for every 1,000 surgeries. “Routine tests . . . don’t seem to have a lot of value,” said Dr. Joseph Foss of the University of Chicago, commenting on the study.
Apples Are Found to Be Beneficial to Lungs
An apple a day is good for the lungs, improving breathing and other lung functions, according to British researchers. The effect probably arises because apples contain high levels of the antioxidant quercetin, which may help protect the lungs from the harmful effects of pollution and cigarette smoke. Quercetin is also found in onions, tea and red wine.
Dr. Barbara Butland and her associates at St. George’s Hospital Medical School in London studied 2,500 Welsh men between the ages of 45 and 59. They began enrolling the men in 1979, studying their diet and measuring various lung functions. The measurements were repeated five years later. Factoring out other variables, they found that men eating five or more apples a week had significantly better lung function, they reported in Thursday’s Thorax.
Tests Show Drug Eases Pain From Diabetes
Preliminary trials show that a new drug can relieve some of the pain of diabetic neuropathy, researchers said Tuesday. As many as 70% of the 10 million U.S. diabetics suffer from at least some nerve damage, according to the American Diabetes Assn. Diabetics with neuropathy experience chronic pain in the lower legs and feet. At night, extreme sensitivity can make the weight of bed sheets excruciatingly painful.
The new drug, called Memantine, appears to restore the function of damaged nerve cells and block abnormal excitatory signals from nerves.
A team headed by Dr. Sherwyn Schwartz of the Diabetes & Glandular Disease Clinic in San Antonio enrolled 375 diabetics in the trial. The patients received either a placebo or one of two doses of Memantine, which is manufactured by Neurobiological Technologies Inc. of Richmond, Calif. After eight weeks of treatment, the company said Tuesday, patients receiving the highest dose of the drug experienced significantly less severe, chronic nighttime pain. The low-dose group, however, did not do much better than those receiving placebos.
Diabetics’ Heart Risk Cut by ACE Inhibitor
Diabetics are also at high risk of developing heart disease, for reasons that are not completely clear. The risk of heart attack and death in diabetic men is two to three times higher than in healthy men and three to five times higher in diabetic women than in healthy women. A new international study has demonstrated that treating diabetics with an angiotensin-converting enzyme, or ACE, inhibitor can sharply lower that risk.
The Heart Outcomes Prevention Evaluation study enrolled 3,577 diabetics from 17 countries, age 55 or older, who had suffered a previous cardiovascular event such as a heart attack or blocked arteries. Half received the ACE inhibitor ramipril, trade-named Altace, and half a placebo. ACE inhibitors lower blood pressure, but they apparently also have other beneficial effects on the heart as well. Nine other ACE inhibitors are on the market, but the team focused only on ramipril.
The team reported in Saturday’s Lancet that the treatment reduced the risk of a heart attack by 22%, the risk of death from cardiovascular disease by 37%, the risk of stroke by 33% and the risk of kidney damage by 24%. The results were so good that the study was halted six months earlier than planned so that all participants could take the drug.
A separate arm of the same study, initially reported in November, showed that vitamin E provided no protective benefits among the same patients.
New Support for Theory on Breast Cancer, Mice
New research from UC Santa Barbara supports the controversial idea that human breast cancer is linked to the common house mouse, Mus domesticus. That species carries a virus called the mouse mammary tumor virus, a close relative of the human mammary tumor virus, and some researchers believe that the mouse virus can trigger human tumors.
Biologist Richard Sage and his colleagues studied the geographical distribution of Mus domesticus and reported in Wednesday’s Cell that the distribution closely matches that of breast cancer. The house mouse is common in Western Europe, North and South America, Australia, New Zealand and Hawaii, and those areas all have a high incidence of breast cancer, Sage found. Women moving from areas where the rodent is uncommon to those with a higher incidence--such as Soviet Jews moving to Israel, Japanese moving to the United States and South Asians moving to the United Kingdom--all show an increased risk of breast cancer compared with other women in their country of origin. Sage and company also cited the case of a female who developed antibodies to the virus after 32 months working in a laboratory with the mice. Nine months later, she developed a mass in her breast.
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Medical writer Thomas H. Maugh II can be reached at thomas.maugh@latimes.com.
