Posts Tagged ‘public’

Hepatitis C will become a rare disease in 22 years, study predicts

“Hepatitis C (HCV) is the leading cause of liver cancer and accounts for more than 15,000 deaths in the U.S. each year,” said Jagpreet Chhatwal, Ph.D., assistant professor of Health Services Research at MD Anderson, and corresponding author on the study.

“If we can improve access to treatment and incorporate more aggressive screening guidelines, we can reduce the number of chronic HCV cases, prevent more cases of liver cancer and reduce liver-related deaths,” Chhatwal said.

HCV — a virus transmitted through the blood — is spread by sharing of needles, the use of contaminated medical equipment, and by tattoo and piercing equipment that has not been fully sterilized. Those at the highest risk for exposure are baby boomers — people born between 1945 and 1965. Widespread screening of the U.S. blood supply for hepatitis C began in 1992. A majority of people were infected through blood transfusions or organ transplants before 1992.

Baby boomers account for 75 percent of the estimated 2.7 to 3.9 million people infected in the United States. Half of people with the virus are not aware they are infected. The Centers for Disease Control and Prevention, and the U.S. Preventive Services Task Force now recommend a one-time HCV screening for this population group.

In this study, Chhatwal and his collaborators used a mathematical model with information from several sources including more than 30 clinical trials to predict the impact of new therapies called “direct-acting antivirals” and the use of screening for chronic HCV cases.

Researchers developed a computer model to analyze and predict disease trends from 2001 to 2050. The model was validated with historical data including a recently published national survey on HCV prevalence. Researchers predicted with new screening guidelines and therapies, HCV will only affect one in 1,500 people in the U.S. by 2036.

The model predicts one-time HCV screening of baby boomers would help identify 487,000 cases over the next 10 years.

“Though impactful, the new screening guideline does not identity the large number of HCV patients who would progress to advanced disease stages without treatment and could die,” Chhatwal said.

“Making hepatitis C a rare disease would be a tremendous, life-saving accomplishment,” said lead author Mina Kabiri, a doctoral student at the University of Pittsburgh Graduate School of Public Health. “However, to do this, we will need improved access to care and increased treatment capacity, primarily in the form of primary care physicians who can manage the care of infected people identified through increased screening.”

In this study, researchers predicted a one-time universal screening could identify 933,700 HCV cases. Chhatwal and his colleagues also predict the universal screening and timely treatment can make HCV a rare disease in the next 12 years. Such screening can further prevent:

• 161,500 liver related deaths,

• 13,900 liver transplants and

• 96,300 cases of hepatocellular carcinoma — the most common type of liver cancer.

Chhatwal, whose current research focuses on evaluations of cancer prevention strategies using quantitative methods, says the availability of highly effective therapies and screening updates provide a great opportunity to tackle the hepatitis C epidemic. “But we need to ensure that we provide timely and affordable access to treatment to achieve the potential benefits.”

“The new treatment that costs $1,000 a day has been a subject of debate and can become a barrier to timely access to all patients,” Chhatwal said.

“Although recent screening recommendations are helpful in decreasing the chronic HCV infection rates, more aggressive screening recommendations and ongoing therapeutic advances are essential to reducing the burden, preventing liver-related deaths and eventually eradicating HCV,” Chhatwal said.

source : http://www.sciencedaily.com/releases/2014/08/140804202048.htm

Mammography benefits women over 75, new study finds

The value of mammography screening in older women has been subject to much debate in recent years. The American Cancer Society recommends annual mammograms for women age 75 and older as long as they are in good health, while the U.S. Preventive Services Task Force (USPSTF) does not recommend mammography screening in this age group, citing insufficient evidence to evaluate benefits and harms.

A lack of research is chiefly responsible for the divergent recommendations, according to Judith A. Malmgren, Ph.D., affiliate assistant professor at the University of Washington’s School of Public Health and Community Medicine in Seattle.

“There are no studies on women age 75 and older, despite the fact that they are at the highest risk for breast cancer,” she said.

Dr. Malmgren and her research partner, Henry Kaplan, M.D., from the Swedish Cancer Institute in Seattle, recently looked at the impact of mammography detection on older women by studying data from an institutional registry that includes more than 14,000 breast cancer cases with 1,600 patients over age 75.

The majority of mammography-detected cases were early stage, while physician- and patient-detected cancers were more likely to be advanced stage disease. Mammography-detected invasive breast cancer patients were more often treated with lumpectomy and radiation and had fewer mastectomies and less chemotherapy than patient- or physician-detected cases.

Mammography detection was associated with a 97 percent five-year disease-specific invasive cancer survival rate, compared with 87 percent for patient- or physician-detected invasive cancers.

“Mammography enables detection when breast cancer is at an early stage and is easier to treat with more tolerable options,” Dr. Malmgren said. “In this study, older women with mammography-detected invasive cancer had a 10 percent reduction in breast cancer disease-specific mortality after five years.”

The early detection provided by mammography is particularly important in older women, Dr. Malmgren noted, because they cannot easily tolerate the chemotherapy that is commonly used to treat more advanced breast cancers.

“Longer life expectancies for women also increase the importance of early detection,” Dr. Malmgren said. “A 75-year-old woman today has a 13-year life expectancy. You only need five years of life expectancy to make mammography screening worthwhile.”

Dr. Malmgren acknowledged that the potential costs of mammography, such as those associated with false-positive results, are an important consideration when weighing screening benefits. However, she said that false-positive findings are less common in older women.

“It’s easy to detect a cancer earlier in older women because breast density is not an issue,” Dr. Malmgren said. “And mammography is not expensive, so doing it every other year would not add a lot of cost to healthcare.”

The researchers hope that the study results help women and their physicians make better informed decisions about mammography, ultimately leading to lower mortality rates.

“Breast cancer survival in younger women has improved dramatically over last 20 years, but that improvement has not been seen in older women,” Dr. Malmgren said.

source : http://www.sciencedaily.com/releases/2014/08/140805091113.htm

Informed consent: False positives not a worry in lung cancer study

“Most people anticipated that participants who were told that they had a positive screen result would experience increased anxiety and reduced quality of life. However, we did not find this to be the case,” said Ilana Gareen, assistant professor (research) of epidemiology in the Brown University School of Public Health and lead author of the study published in the journal Cancer.

The NLST’s central finding, announced in 2010, was that screening with helical CT scans reduced lung cancer deaths by 20 percent compared to screening with chest X-rays. The huge trial spanned more than a decade, enrolling more than 53,000 smokers at 33 sites.

In the new study, Gareen and co-authors, including Brown faculty and staff members Fenghei Duan, Constantine Gatsonis, Erin Greco, and Bradley Snyder, followed up with a subset of participants at 16 sites to assess the psychological effects of the CT and X-ray screenings compared in the trial.

“In the context of our study, with the consent process that we used, we found no increased anxiety or decreased quality of life at one or six months after screening for participants having a false positive,” Gareen said. “What we expected was that there would be increased anxiety and decreased quality of life at one month and that these symptoms would subside by six months, which is why we measured at both time points, but we didn’t find any changes at either time point.”

The unexpected similarity between the participants with a negative and a false positive screen result is not because getting a false positive diagnosis is at all pleasant, Gareen said, but presumably because study participants understood that there was a high likelihood of a false positive screen result.

“We think that the staff at each of the NLST sites did a very good job of providing informed consent to our participants,” she said. “In advance of any screening, participants were advised that 20 to 50 percent of those screened would receive false positive results, and that the participants might require additional work-up to confirm that they were cancer free.”

Reassuring results

To make its assessments, Gareen’s team surveyed 2,812 NLST participants for the study. Patients responded well, with 2,317 returning the survey at one month after screening and 1,990 returning the survey at six months. The survey included two standardized questionnaires: the 36-question Short Form SF-36, which elicits self-reports of general physical and mental health quality, and the 20-question Spielberger State Trait Anxiety Inventory.

Maryann Duggan and her staff from the Outcomes and Economics Assessment Unit at Brown administered the questionnaires by mail with telephone follow-up as required.

In the study analysis, the researchers divided people into groups based on their ultimate accurate diagnoses: 1,024 participants were “false positive,” 63 were “true positive,” 1,381 were “true negative” and 344 had a “significant incidental finding,” meaning they didn’t have cancer but instead had another possible problem of medical importance.

The results were clear after statistical adjustment for factors that could have had a confounding influence. Whether participants received X-rays or the helical CT scans, the questionnaire scores of those with false positive diagnoses remained similar to those who were given true negative diagnoses.

Meanwhile, the scores of the true positive participants who were diagnosed with lung cancer markedly worsened over time as their battle with the disease took a physical and psychological toll.

Because participants received the questionnaires at one and six months, it is possible that study participants receiving a false positive screen result experienced anxiety and reduced quality of life for a short time after receiving their screen result, Gareen said. But by one month after their screening, there was no evidence of a difference between the screen result groups.

Gareen said the results should encourage physicians to recommend appropriate screenings, despite their high false positive rates, so long as patients are properly informed of the likelihood of a positive screen result and its implications. The data provide evidence that the NLST consent process provided a good model for advising those undergoing screening, she said.

source : http://www.sciencedaily.com/releases/2014/07/140725080404.htm