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Does milk fight bowel cancer

The study was carried out by researchers from University of Otago Medical School, New Zealand. Funding was provided by Genesis Oncology Trust, the Dean’s Bequest Funds of the Dunedin School of Medicine, the Gisborne East Coast Cancer Research Trust and the Director’s Cancer Research Trust. The research was published in the peer-reviewed American Journal of Epidemiology. This was a case-control study in New Zealand that compared a group of adults with bowel cancer, and a group without bowel cancer, and looked at whether they drank milk at school. School milk was freely available in most schools in New Zealand until 1967 when the government programme was stopped. Many schools in the Southland region stopped free milk as long ago as 1950.

Case-control studies are appropriate for looking at whether people with and without a disease have had a particular exposure (milk in this case). The difficulty is in accounting for all potential confounding factors, particularly other health and lifestyle factors, which could be related to both diet and bowel cancer risk, for example regular childhood milk consumption could be a reflection of a ‘healthy’ diet and other healthy lifestyle behaviours that may reduce risk of cancer. In addition, when examining such a specific dietary factor – ie milk consumed in school – it is difficult to account for all possible milk or other dairy products consumed outside of school.

In this case-control study, 562 adults (aged 30 to 69) with newly diagnosed bowel cancer were identified from the New Zealand Cancer Registry in 2007. For a control group, 571 age-matched adults without cancer were randomly selected from the electoral register. All participants were mailed a questionnaire that asked about any previous illness, use of aspirin or dietary supplements in childhood, participation in school milk programmes, other childhood milk consumption, childhood diet (including other milk and dairy), smoking, alcohol consumption prior to 25 years of age, screening tests for bowel cancer, family history of cancer, education and sociodemographic characteristics. Childhood weight and height were not questioned. For school milk consumption they were specifically asked:

  • Whether they drank school milk
  • How many half-pint bottles they drank a week
  • What age they first drank school milk
  • When they stopped drinking school milk

Statistical risk associations between school milk participation and cancer were calculated. The calculations took into account several risk factors for bowel cancer risk including age, sex, ethnicity and family history.

What were the basic results?

Data on school milk consumption was available for 552 cases and 569 controls. As expected, people who started school before 1967 were more likely to have had free school milk than those who began school after 1968. Seventy-eight percent of cases participated in the school milk programme compared with 82% of controls. School milk consumption was associated with a 30% reduced risk of developing bowel cancer (odds ratio 0.70, 95% confidence interval 0.51 to 0.96).

When looking at the effect of number of bottles consumed per week they found that compared with no bottles, five bottles per week was associated with 32% significantly decreased risk, and 10 or more bottles with 61% significantly decreased risk. However, there was no significant association with one to four bottles or six to nine bottles. The researchers found a similar trend when the total school consumption of milk was compared with no consumption: 1,200-1,599 bottles was associated with 38% significantly decreased risk; 1,600-1,799 with 43% decreased risk; and 1,800 or more bottles associated with 38% significantly decreased risk. There was no significant association with fewer than 1,200 bottles. The researchers calculated that for every 100 half-pint bottles consumed at school there was a 2.1% reduction in the risk of bowel cancer. Outside of school, there was a significantly reduced risk of bowel cancer with more than 20 dairy products a week compared with none to nine dairy products a week.

The researchers conclude that their national case-control study ‘provides evidence that school milk consumption was associated with a reduction in the risk of adult colorectal cancer in New Zealand. Furthermore, a dose-dependent relation was evident’. This study has strengths in its relatively large size, its reliable and nationally representative identification of cases and controls, and its thorough data collection. However, the conclusion that school milk consumption is associated with a reduced risk of bowel cancer in adulthood must be interpreted in light of a number of considerations:

The analysis took into account established risk factors for bowel cancer including age, sex, ethnicity and family history. However, many other potential confounders were not considered, including diet, physical activity, overweight and obesity, smoking or alcohol consumption. Diet in particular has been implicated in bowel cancer risk, with diets high in saturated fat, red meat and processed foods and low in fibre, fruit and vegetables thought to increase risk. Potentially, any of these lifestyle behaviours could be confounding the relationship between school milk consumption and bowel cancer and regular childhood milk consumption could be a reflection of a ‘healthy’ diet and other healthy lifestyle behaviours that reduce risk of cancer. When looking at the effect of number of bottles consumed per week, the researchers found that, compared with no bottles, five bottles were associated with 32% significantly decreased risk and 10 or more bottles with 61% significantly decreased risk. However, there was no significant association with one to four bottles or six to nine bottles. Therefore, the trend here is not very clear. Particularly as only 16 cases and 31 controls drank 10 or more bottles a week, statistical comparison between such small numbers should be viewed with caution. With many food questionnaires there is the potential for recall bias. For example, adults may have difficulty remembering how many bottles of school milk they drank many years before. When estimating their average weekly amount, it is highly possible that this could be inaccurate or that their consumption varied slightly from week to week and year to year. Particularly when researchers were using this response and combining it with the number of weeks in the school year and their total years at school to give a total number of bottles consumed at school (figures in 100s or 1,000s), there is the possibility of being incorrectly categorised. Hence, there may be less reliability when calculating risk according to the category of total milk bottles consumed. Cancer prevalence, and particularly environmental and lifestyle risk factors for cancer, can vary between countries. These findings in New Zealand may not be represented elsewhere. Of note, the researchers acknowledge that a cohort study in the UK found the opposite: increased childhood dairy consumption was associated with increased risk of bowel cancer. Case-control studies are most appropriate for looking at rare diseases, where you would expect there to be only a small number of cases developing among a large number of people. In the case of bowel cancer, which is common, the slightly more reliable cohort design could have also been used, where children who drank milk at school and those who didn’t were followed over time to see if they developed cancer. However, such a cohort would consequently need extensive long-term follow-up.

The possible association between milk/dairy consumption, or calcium intake, in childhood, or in later years, is worthy of further study. However, from this study alone, it cannot be concluded that school milk prevents bowel cancer later in life.

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Low Level of “Good” Cholesterol Associated with Alzheimer’s

A low level of “good” cholesterol is a well-known risk factor for heart disease. A new study by investigators at Columbia University College of Physicians & Surgeons now suggests that a low level of good cholesterol may also raise the risk of developing Alzheimer's disease.

“Low levels of 'good' cholesterol (a.k.a. high-density lipoproteins or HDL) are very common in the United States,” says the study's lead author, Christiane Reitz, MD, PhD, assistant professor of neurology (in the Sergievsky Center and Taub Institute). “If raising HDL can lower a person's risk of developing Alzheimer's disease, that means we may be able to significantly reduce the rate of Alzheimer's disease in the population,” Reitz says, though she cautions that the finding still must be confirmed in other studies.

The study, which appears in the December issue of Archives of Neurology, is co-authored with Jose Luchsinger, MD, MPH, associate professor of medicine and epidemiology, and Richard Mayeux, MD, director of the Gertrude Sergievsky Center and Sergievsky Professor of Neurology, Psychiatry, and Epidemiology.

Previously, the relationship between HDL and Alzheimer's disease had been unclear. Some studies found an association, but others, including one of Reitz's own, found no connection. The new study, Reitz says, follows subjects for a longer period of time than previous studies, resulting in a more accurate account of the number of subjects who ultimately develop Alzheimer's.

After monitoring 1130 elderly residents of northern Manhattan for an average of four years, the researchers found a 40 percent higher incidence of Alzheimer's in residents with low HDL (less than 55 mg/dl). The reason that low HDL is associated with a higher rate of Alzheimer's isn't understood. One possibility is that it works through stroke. “We know low HDL raises the risk of stroke and that stroke is associated with Alzheimer's, so stroke may be the mediator,” Reitz says. “But there's also evidence that HDL works by itself to clear amyloid proteins [the proteins believed to cause Alzheimer's] from the brain.”

Because the study included a large number of African Americans and Hispanics, unlike previous studies that focused on whites, the finding may indicate that low HDL is linked to a high risk of Alzheimer's in many different ethnicities.

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Vitamin D affects more than 200 genes

Working in the laboratory, the scientists isolated fragments of DNA in cells to study the effects of exposure to calcitriol, the “active” form of vitamin D. Their findings are published in the journal Genome Research.

Vitamin D influences DNA through a “go-between” protein called the vitamin D receptor (VDR). The protein is activated by the vitamin and attaches itself to DNA at the binding sites the researchers identified. VDR binding was enriched in disease-associated regions of the genetic code and also areas linked to traits such as tanning, height and hair colour.

Study leader Dr Sreeram Ramagopalan, from the Wellcome Trust Centre for Human Genetics, at Oxford University, said: “There is now evidence supporting a role for vitamin D in susceptibility to a host of diseases. Vitamin D supplements during pregnancy and the early years could have a beneficial effect on a child's health in later life. “Some countries, such as France, have instituted this as a routine public health measure.”

Vitamin D is chiefly made in the body as a result of the skin's exposure to sunlight. A small number of foods also contain the vitamin, including oily fish and eggs, but 90% comes from being in the sun. In many northern countries, a lack of sun can lead to vitamin D deficiency. Over-zealous use of sunscreen can also prevent vitamin D production. It is estimated that more than half the UK population do not get enough vitamin D, and worldwide a billion people may be deficient in the vitamin. Lack of vitamin D affects bone growth and development, leading to rickets in children and bone fractures in adults.

The study supports the theory that lighter, more sun-sensitive skins evolved as people migrated north out of Africa to maximise vitamin D production in the body. A significant number of the VDR binding sites were in DNA regions where genetic changes are commonly found in people of European and Asian descent.

“Vitamin D status is potentially one of the most powerful selective pressures on the genome in relatively recent times,” said co-author Professor George Ebers, also from the Wellcome Trust Centre for Human Genetics. “Our study appears to support this interpretation and it may be we have not had enough time to make all the adaptations we have needed to cope with our northern circumstances.”

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Taking exams: revision tips

By making a plan and organising your time, you can divide your revision into manageable chunks. This will increase your chances of remembering the important facts, and help you avoid last-minute stress.

Find out what you need to know

Make your revision plan as early as possible. This will allow you to work out how much time to spend revising each day and, just as importantly, when to take breaks.

The first step is to get organised: find out when your exam is, and work out how much time you have until then.

Write a revision checklist

Start by dividing the number of days you have until the exam by the number of topics you need to revise. Ask your teacher for a list of topics, or make your own by going through your notes.

Think about any topics that will need more revision time – perhaps you covered them in more detail, or you found them more difficult.

Make a revision plan

When you know how many days you need to spend revising each topic, you'll be able to make revision part of your daily routine. However, you need to be realistic:

  • set aside time on your plan for things you need to do, like going to school and mealtimes
  • split the remaining time into half-hour slots
  • break each topic on your revision checklist down into chunks that you can cover in 30 minutes, and fill your slots with these chunks

Reading your revision notes

When going over your notes, keep in mind what you're looking for:

  • read for detail when you need to a good understanding of the text – take it slowly and ask yourself questions while you're reading
  • 'skim' to get the general idea of a large piece of text – read each paragraph quickly, and identify the main ideas in each one
  • 'scan' to look for a specific piece of information – move quickly through the text, homing in on sub-headings, names, numbers, dates and quotes

Look after yourself

Regular breaks are important if you're going to stay alert while revising. A five-minute break every half-hour is better than a 30-minute break after five hours. Get up, make a drink, tidy your room, check your email – you'll come back refreshed and ready to carry on. Breaks will also help you absorb the information and avoid overload.

Make sure you include a leisure activity in your revision plan twice or three times a week. It's important to set aside time to take your mind off exams.

A healthy mind needs a healthy body, so look after yourself. Lots of sleep and regular exercise will help you stay alert. Your body needs fuel, so eat plenty of easily digestible foods – fresh vegetables and fruit will help keep your energy levels up.

Getting support

If you have any personal problems – for example, with relationships or bullying – there's help available. Try to get support before your revision suffers.

Source: Directgov. Reproduced with permission.

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General Information

Definition

Chronic Fatigue Syndrome (CFS) was originally defined in 1988 when the Center for Disease Control (CDC) in the US brought together a number of researchers who had been investigating a strange syndrome characterized by overwhelming fatigue. This definition however was reviewed by a panel of international experts in 1994 and subsequently revised.

CFS is very difficult to diagnose because the main symptom of fatigue is present in so many other illnesses. However, once other illnesses have been ruled out through laboratory tests and physical examination, a diagnosis of CFS may be given if the following criteria are met:

Clinically evaluated, unexplained persistent or relapsing chronic fatigue that is of new or definite onset (i.e., not lifelong), is not the result of ongoing exertion, is not substantially alleviated by rest, and results in substantial reduction in previous levels of occupational, educational, social, or personal activities.The concurrent occurrence of four or more of the following symptoms: substantial impairment in short-term memory or concentration; sore throat; tender lymph nodes; muscle pain; multi-joint pain without swelling or redness; headaches of a new type, pattern, or severity; unrefreshing sleep; and post-exertional malaise lasting more than 24 hours. These symptoms must have persisted or recurred during 6 or more consecutive months of illness and must not have predated the fatigue.

The full text of the revised definition can be found at the CDC website: http://www.cdc.gov/ncidod/diseases/cfs/about/definition/index.htm

Symptoms and General Information

Obviously, as is implied by the various names, fatigue is the major symptom in CFS. People often have the misconception that this is the only symptom and hence they assume that sufferers simply like to complain about the normal tiredness that everyone experiences after a day at work etc. CFS is actually much more than fatigue, and the fatigue experienced is a lot more severe than simple tiredness. The following is a list of the major symptoms of CFS.

  • Fatigue
    • Exercise Intolerance
    • Severe Malaise
    • Muscle and Joint Aches
    • Cognitive Dysfunction
    • Chronic Headache
    • Balance Disturbance
    • Recurrent Sore Throat
    • Mood and Sleep Disturbances
    • Abdominal Pain/Digestive Disturbances
    • Sensitivity to Light and/or Sound
    • Visual Disturbances
    • Skin Sensitivity

Possible Causes

The cause, or causes of ME/CFS are still not clear. There are a number of theories that have been proposed, the main ones propose the following factors as the cause or causes of the illness:

  • Viral Infection
  • Mycoplasma Infection
  • Immune or Endocrine Dysfunction
  • Autonomic Nervous System Dysfunction
  • Environmental Toxins
  • Genetic Factors
  • Candida Overgrowth
  • Gut Dysbiosis
  • Heavy Metal Sensitivity
  • Emotional Stress or Trauma

There may be a large number of abnormalities in multiple body systems in CFS patients. These abnormalities centre around the nervous, endocrine and immune systems and the way these interact with each other. Although these abnormalities have been identified it is still unclear which are causes and which are effects. New research will hopefully shed more light on this but until then doctors who are seeing the best results with patients seem to be those who take a multifactorial approach and try to correct as many of the abnormalities discussed as they possibly can, using currently available treatments.

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Growing number of women with Gout

The number of women suffering from gout has doubled in the last 20 years, research shows.

The problem is traditionally associated with middle aged men but evidence suggests the disease is also a concern for women. According to a survey, the prevalence of gout in women was 3.5 per cent for ages 60 to 69, 4.6 per cent in the 70 to 79 age group, and 5.6 per cent in those aged 80 or older.

Gout is a common and painful inflammatory arthritis caused by elevated uric acid levels in the blood. When too much uric acid builds up in joint fluid, crystals form and cause joint swelling and inflammation. Dr Hyon Choi, from the Boston University School of Medicine, which conducted the review of previous research, said: “We identified 104 gout cases in women and 200 in men. “Our study found that higher levels of uric acid in the blood increase the risk gout risk for women.”

This study, the first to examine the relationship between uric acid levels and gout risk in women, also evaluated purported risk factors for gout and found that increasing age, obesity, hypertension, alcohol use, and diuretic use to be among the leading contributors for women.

The research team analysed data from 2,476 women and 1,951 men, and evaluated uric acid levels and risk factors for gout that included: age, body mass index (BMI), alcohol consumption, hypertension, medication use – including diuretics and hormone replacement therapy – blood glucose and cholesterol levels, and menopause status. The study looked at men and women from various health sources and records over an average of 28 years. The researchers found age, obesity, alcohol consumption, diuretic use, and hypertension were all independently associated with higher risk of gout incidence in women.

The study was published in the April issue of Arthritis & Rheumatism, a journal of the American College of Rheumatology.

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Kids and Type 2 Diabetes

 

Type 2 Diabetes in Kids: Symptoms and Risk Factors

Type 2 diabetes is a condition that occurs when the body doesn't produce enough insulin or can't properly use the insulin that it produces. When the body can't respond normally to insulin, glucose builds up in the blood.

Type 2 diabetes sometimes is difficult to detect in children because symptoms may be mild or absent. However, symptoms still play a key role in diagnosing type 2 diabetes in children. These symptoms include excessive thirst, frequent urination, tiredness or lack of energy, and acanthans nigricans (darkening of the skin between the fingers and toes and near the shoulder blades). If your child displays one of these symptoms, it doesn't necessarily mean he or she has type 2 diabetes, but a visit to the doctor is a good idea.

According to the ADA, risk factors for type 2 diabetes in children include

  • Being overweight—as many as 80 percent of children are overweight when diagnosed
  • Being older than 10 years of age and in middle-to-late puberty (although some children with type 2 diabetes are younger)
  • Having a family history of type 2 diabetes
  • Being a member of certain racial/ethnic groups 

Being Overweight: A Risk Your Family Can Avoid

The recent increase in type 2 diabetes among children parallels the rising number of overweight children. For that reason, some experts believe that being overweight is the most significant risk factor for type 2 diabetes in children. In a way, that's good news because being overweight is the one risk factor you and your family can take charge of.

A physically active lifestyle and good eating habits are central to preventing weight problems. If your child is already overweight, ask your child's doctor or Nastaran for advice on the best treatment plan.

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