STUDY: Blood screening can identify genetic predisposition

JOURNAL: Johns Hopkins University

AUTHORS: Feinberg, Hengmi Cui, Marcia Cruz-Correa

ABSTRACT: A simple blood test may be able to predict who is at risk of colon cancer offering a way to avoid the embarrassing ordeal of a colonoscopy.

---

COMMENTARY: They found a single genetic change that was much more common in people with a family history of colon cancer and extremely common in people diagnosed with colon cancer.

Feinberg, Hengmi Cui, Marcia Cruz-Correa and others tested 172 patients at a colonoscopy clinic. They were looking for a specific genetic change called loss of imprinting.

This is not a genetic mutation, but a mistake in how the genes work. People get two copies of each gene — one from each parent — but some are imprinted so that only one copy works.

Feinberg’s lab had previously found that a gene called IGF2, which controls production of insulin-like growth factor 2, had “loss of imprinting” in some forms of cancer.

“In this case both copies are working. This is a gene for cell growth and it makes sense that getting a double dose might lead to cancer,” he said. They looked for this change both in the blood and in samples taken from the patients’ colons.

Those who had colon cancer or who had it in the past were nearly 22 times as likely to have the change, they found — and they could detect it in the blood in most cases.

Now they will have to see if other patients who had the change go on to develop cancer, Feinberg said.

And if the tests hold true in larger groups of people, it may be possible to develop a quick blood test to look for colon cancer risk.

STUDY: Most healthy couples get pregnant within two years

JOURNAL: European Society of Human Reproduction and Embryology

AUTHORS: Dr. David Dunson

ABSTRACT: Most healthy couples who are worried because the woman is not pregnant after a year of trying will conceive during the second year, a new study shows.

---

COMMENTARY: Couples should not rush to fertility clinics and doctors should not intervene too fast with treatments unless there are obvious reasons for the couple not conceiving.

Infertility is defined as failure to get pregnant after a year of trying.

Many fertility clinics report couples coming in at younger ages, but the new research shows that even couples in their late 30s have a 91 percent chance of getting pregnant naturally within two years.

The study, which analyzed details of 782 couples from seven European cities, was presented Wednesday at a meeting of the European Society of Human Reproduction and Embryology.

Couples are waiting longer these days before starting families and experts have recently discovered that the age of the man matters too.

Research earlier this year suggested that fertility declines earlier than previously thought — in the late 20s for women and late 30s for men.

There is a large amount of normal variability in fertility and many couples who have below-average, but normal, fertility may fail to conceive within a year.

It may be appropriate to delay assisted reproduction until the couple has failed to conceive naturally in 18 to 24 months.

A factor that we have seen at the clinic is that following the BTD can increase a couples chance of conceiving by reducing food induced opposing antibodies in the female reproductive tract.

STUDY: New way of calculating odds finds older estimates pessimistic

JOURNAL: Lancet

AUTHORS: Hermann Brenner

ABSTRACT: The chances of surviving many types of cancer are better than statisticians thought, according to a new way of calculating the odds that takes into account improvements in treatment.

---

COMMENTARY: The new approach, proposed by German epidemiologist Hermann Brenner, is commonly used in other areas of medicine, such as predicting life expectancy.

In the Lancet study, Brenner analyzed more than 1.7 million patients recorded in the U.S. National Cancer Institute database.

He found that the new method estimates American breast cancer patients had a 71 percent chance of surviving 15 years, while the conventional approach put the chance at 58 percent.

Similarly, the 15-year survival rate for American men with testicular cancer was 91 percent, compared to 86 percent with the old method.

The survival rate for ovarian cancer five years after diagnosis was 55 percent with the new method, compared with 49 percent previously.

The conventional method of estimating cancer-patient survival, called the cohort approach, estimates the chances of surviving a particular cancer for, say 10 years, by looking at what has happened to patients diagnosed between 1990 and 2000.

“Cohort estimates are generally not appropriate for predicting the survival of newly diagnosed patients since the estimates are heavily weighted toward the survival experience of patients diagnosed many years in the past,” said Paul Dickman, a professor of biostatistics at the Karolinska Institute in Stockholm, Sweden, who is a proponent of the new method but was not connected with the latest study.

The new approach, called period analysis, is based only on recent years — for example, on patients who were alive and under follow-up during the year 2000.

STUDY: The diet type is much less important than the actual restriction in calories.

JOURNAL: J Clin Endo Metab 2003;88:812-819.

AUTHORS: Dr. L. J. Moran

ABSTRACT: Overweight women with polycystic ovary syndrome (PCOS) experience an improvement in their symptoms after a few months of dieting, regardless of whether they opt for a low or high protein diet.

---

COMMENTARY: The diet type is much less important than the actual restriction in calories.

A group of Australian researchers led by Dr. L. J. Moran at the University of Adelaide assigned 45 overweight women with PCOS to either high- or low-protein diets.

The high-protein diet consisted of 30% protein and 40% carbohydrates, while the low-protein diet included 15% protein and 55% carbohydrates. The women were expected to eat a calorie-restricted diet--approximately 1400 calories per day--for 12 weeks, then to spend another 4 weeks consuming enough calories to maintain, but not change, their body weight.

Study participants were also asked to exercise at least 3 times a week.

Only 14 women assigned to each diet were able to complete the entire program. The authors discovered that both diets resulted in roughly the same amount of weight loss, and the same decrease in body fat and insulin levels.

Almost half of all participants improved the regularity of their periods, the authors note, and 3 out of 20 women trying to conceive did so during the study period. None of the women reported any side effects from the diets.

STUDY:

JOURNAL: Chest 2002;122:1535-1542.

AUTHORS: Ellen McDonald

ABSTRACT: Overall, the use of air filters is associated with fewer symptoms among patients with allergies and asthma.

---

COMMENTARY: Ellen McDonald, RN and colleagues from McMaster University, Hamilton, Ontario, Canada, systematically reviewed the evidence of 10 randomized trials evaluating the effects of air filtration systems on asthmatic patients.

They abstracted data on the methodolgic quality, population, intervention, and outcomes from studies identified using MEDLINE, the Cumulative Index to Nursing and Allied Health Literature, and the Cochrane Collaboration.

Of the 10 studies reviewed, five enrolled adults only and one included children only. A total of 216 patients were included in all the studies, with the sample size ranging from 9 to 45 subjects.

A significant decrease in airway responsiveness associated with air filter use was reported in two studies. An association was observed between air filters and significantly lower total symptoms scores and lower sleep disturbance score.

The investigators observed no association between air filter utilization and any differences in medication use or morning peak expiratory flow values.