Timing of Hormone Therapy Impacts Cancer Risk

(American Health Newswire) -- A new study reveals starting hormone therapy around the time of menopause is linked to a greater risk of breast cancer compared to starting it later on.

Several past studies have shown an increase in breast cancer risk among women who use hormonal therapy. However, few studies have examined the role that timing plays as a risk factor for this type of cancer.

Researchers from Oxford University analyzed data on 1.13 million women who were enrolled in the Million Women Study in the United Kingdom. The researchers estimated the adjusted relative risks of breast cancer in hormone therapy users and past users compared to non-users. They also compared women on different types of hormone therapy.

They found that women who started hormone therapy at the time of menopause were at a greater risk for developing breast cancer than those who started it later. "This pattern of risk was seen across different types of hormonal therapy, among women who used hormonal therapy for either short or long durations, and also in lean and in overweight and obese women," the authors wrote.

SOURCE: Journal of the National Cancer Institute, January, 2011

Lack of Vitamin D Affects Lung Function

(American Health Newswire) -- Vitamin D deficiency was previously linked to severe asthma and chronic obstructive pulmonary disease (COPD), but a new study shows it also alters lung structure and function in young mice.

"The results of this study clearly demonstrate that vitamin D deficiency alters lung growth, resulting in lower lung volume and decrements in lung function," Graeme Zosky, Ph.D., a research fellow at the Telethon Institute for Child Health Research in Subiaco, Australia, was quoted as saying. "This is the first direct mechanistic evidence showing that vitamin D deficiency alters lung development, which may explain the association between obstructive lung disease and levels of vitamin D."

Researchers studied mice with vitamin D deficiency and evaluated lung responses of two-week-old mice and compared them to control mice without vitamin D deficiency to see the effects the deficiency may have cause in the growth, structure, or function of the lungs.

Lung volume and lung function were evaluated using a plethysmograph, an instrument used to measure the amount of air in the lung, and via forced oscillation, a technique used to measure the resistance to air flow in the lungs. Microscopic lung tissue samples were also evaluated to assess changes in lung structure.

"The aim of this study was to determine if vitamin D deficiency results in altered lung function and/or structure as a potential explanation for the association between vitamin D and chronic respiratory disease," Dr. Zosky, who is also an adjunct senior lecturer at the University of Western Australia's Centre for Child Health Research, was quoted as saying. "Specifically, we aimed to determine if vitamin D deficiency has an influence on lung growth as indicated by a decrease in lung volume. We also wanted to determine if the deficiency alters the mechanical properties of the lung tissue due to changes in the structure of the lung."

The study showed that airway resistance was much higher while lung volume was significantly lower in vitamin D deficient mice compared to control mice. Examinations of specific tissue responses revealed model mice had reduced lung function. Lungs were also smaller in model mice, which Dr. Zosky said could have been caused by the deficiencies of the mother or of the offspring.

"Due to the nature of this study, we were not able to determine whether the differences in lung size and function we observed in the deficient offspring were the result of their own deficient status or as a consequence of developmental deficits that occurred in-utero due to the mother's deficiency," Dr. Zosky said.

"For the first time, we have demonstrated a direct role for vitamin D in causing decreased lung function in the absence of known confounders such as physical inactivity, confirming the assertion by epidemiological studies that there is a relationship between vitamin D deficiency and lung function," Dr. Zosky explained. "The differences we observed in lung volume and lung mechanics, which were substantial and physiologically relevant, raise serious concerns regarding the increased prevalence of vitamin D deficiency in communities around the world. The results also raise concerns about the potential this deficiency may have on lung health, and in particular, the potential impact deficiency may have on the susceptibility to obstructive lung disease."

SOURCE: American Journal of Respiratory and Critical Care Medicine, published online January 28, 2011

Trouble Sleeping? Try Counseling

(American Health Newswire) -- A new report shows that brief counseling sessions can help improve insomnia in older adults.

According to background information in the article, insomnia affects anywhere from 15 to 35 percent of older adults. For the research, Daniel J. Buysse, M.D., of the University of Pittsburgh  - School of Medicine, and his colleagues, conducted a randomized clinical trial that involved 79 insomniacs (all over the age of 60). Thirty-nine received treatment that was made up of individualized behavioral instruction.

Throughout four sessions (two in person, two by phone), a clinician examined those patients' sleep patterns and made specific behavioral recommendations on how they could change them to improve their sleep quality. The remaining adults were given only general educational material about insomnia and sleep habits.

All of the participants kept two-week sleep diaries and underwent sleep assessments before treatment and four weeks after. After four weeks, about 65 percent of individuals who received the brief behavioral treatment showed a favorable response, and about 55 percent were classified as no longer having insomnia.

"I think the bottom line is that behavioral treatments for insomnia can be very effective, and they don't have to be prolonged and complicated. There are some very simple strategies that can help a lot of people who have this common sleep problem," Dr. Buysse told American Health.

Based on the results, the authors were able to estimate that for every 2.4 patients treated, one would respond favorably, and one would no longer meet criteria for insomnia. Dr. Buysse says he believes the treatment can be effective for all age groups.

"Our particular study focused on older adults, but we don't think the effects of these treatments are limited to older adults," Buysse concluded.

SOURCE: Archives of Internal Medicine, January 24, 2011