Sunday, November 25, 2007


I guess it makes me weird but I do find the medical literature to be a barrel of laughs. They are so determined to come to their predetermined conclusions and the data keeps letting them down so badly! Read either the media summary below or the conclusion to the journal abstract also below and you will be left with the impression that being overweight is a bad thing. Read the bit I have highlighted in red and I think you will have a little laugh, though. Even in this highly selected group, fatties were NOT likely to die sooner. They did have more trouble with their prostate cancer but they obviously had less trouble with other things!

Excess weight a risk to surviving cancer

A new study has found that overweight or obese men are at greater risk of death following prostate cancer treatment. Published online this week in the journal Cancer, the study involved 788 men with prostate cancer who were followed for more than eight years. Compared to men with a normal body mass index (BMI, calculated as the weight in kilograms divided by the squared height in metres) of less than 25 at the time of diagnosis, men with a BMI between 25 and 30 were more than 1.5 times more likely to die from their cancer following treatment. Similarly, men with a BMI of 30 or more were 1.6 times more likely to die from the disease. Further research is needed, say the authors, to test whether losing weight after cancer diagnosis could improve survival time.


Obesity and mortality in men with locally advanced prostate cancer

By Jason A. Efstathiou et al.

BACKGROUND: Greater body mass index (BMI) is associated with shorter time to prostate-specific antigen (PSA) failure following radical prostatectomy and radiation therapy (RT). Whether BMI is associated with prostate cancer-specific mortality (PCSM) was investigated in a large randomized trial of men treated with RT and androgen deprivation therapy (ADT) for locally advanced prostate cancer.

METHODS: Between 1987 and 1992, 945 eligible men with locally advanced prostate cancer were enrolled in a phase 3 trial (RTOG 85-31) and randomized to RT and immediate goserelin or RT alone followed by goserelin at recurrence. Height and weight data were available at baseline for 788 (83%) subjects. Cox regression analyses were performed to evaluate the relations between BMI and all-cause mortality, PCSM, and nonprostate cancer mortality. Covariates included age, race, treatment arm, history of prostatectomy, nodal involvement, Gleason score, clinical stage, and BMI.

RESULTS: The 5-year PCSM rate for men with BMI <25 kg/m2 was 6.5%, compared with 13.1% and 12.2% in men with BMI 25 to <30 and BMI 30, respectively (Gray's P = .005). In multivariate analyses, greater BMI was significantly associated with higher PCSM (for BMI 25 to <30, hazard ratio [HR] 1.52, 95% confidence interval [CI], 1.02-2.27, P = .04; for BMI 30, HR 1.64, 95% CI, 1.01-2.66, P = .04). BMI was not associated with nonprostate cancer or all-cause mortality.

CONCLUSIONS: Greater baseline BMI is independently associated with higher PCSM in men with locally advanced prostate cancer. Further studies are warranted to evaluate the mechanism(s) for increased cancer-specific mortality and to assess whether weight loss after prostate cancer diagnosis alters disease course. Cancer 2007. c 2007 American Cancer Society.


Dads 'make young sons dumber'

The original paper is here. It is a long (155 pages), verbose and exhausting paper to read and I do not remotely have the time to read it all but two things I note is that we are primarily talking about lower class (unemployed) fathers here and that the analysis was very "lumpy". Appendix D shows that only two categories were used to examine the amount of time fathers spent with children. That very effectively obscures any possibility of discovering curvilinear relationships -- which are certainly not a possibility that can be excluded a priori in this case.

I also note that the author seems to contradict herself in the first and last paragraphs below. Amusing. Easy to see why, though. We are not allowed to come to conservative conclusions and the paper does come to the thoroughly conservative conclusion that children are best cared for by their mothers! Horrors!

YOUNG boys end up being dumber when it is the father who looks after them as toddlers, a study from Bristol University in the UK has found. A researcher from the University of Bristol in the UK has found that boys are doing worse at school when it was their fathers who spent at least 15 hours each week taking sole care of them.

According to Elizabeth Washbrook's study of more than 6000 children found that "some fathers appear not to provide the same quality of intellectual stimulation as mothers, at least to their sons". "I find robust evidence that boys - but not girls - who spend at least 15 hours a week in paternal care when they were toddlers performed worse on academic assessments when they started school," Ms Washbrook wrote in the Research in Public Policy journal. "This cannot be explained by the economic or psychological characteristics of parents in these families, nor by the characteristics of the child."

Ms Washbrook said that the findings suggest that fathers may be more inclined to believe that taking care of their son was more about "monitoring the child" than devising creative activities. She said that two possible reasons why daughters were not affected by similar time with their fathers were because dads may behave differently around them and girls may be less sensitive to a lack of creative activities - although she also said that there was no definitive proof that supported either argument.

But Ms Washbrook said that the introduction of paid paternity leave in the UK may have led to greater social abilities in children of both genders. "If paternity leave encourages fathers to undertake moderate childcare responsibilities when their children are toddlers, this may have beneficial effects on children's social development."



Just some problems with the "Obesity" war:

1). It tries to impose behavior change on everybody -- when most of those targeted are not obese and hence have no reason to change their behaviour. It is a form of punishing the innocent and the guilty alike. (It is also typical of Leftist thinking: Scorning the individual and capable of dealing with large groups only).

2). The longevity research all leads to the conclusion that it is people of MIDDLING weight who live longest -- not slim people. So the "epidemic" of obesity is in fact largely an "epidemic" of living longer.

3). It is total calorie intake that makes you fat -- not where you get your calories. Policies that attack only the source of the calories (e.g. "junk food") without addressing total calorie intake are hence pissing into the wind. People involuntarily deprived of their preferred calorie intake from one source are highly likely to seek and find their calories elsewhere.

4). So-called junk food is perfectly nutritious. A big Mac meal comprises meat, bread, salad and potatoes -- which is a mainstream Western diet. If that is bad then we are all in big trouble.

5). Food warriors demonize salt and fat. But we need a daily salt intake to counter salt-loss through perspiration and the research shows that people on salt-restricted diets die SOONER. And Eskimos eat huge amounts of fat with no apparent ill-effects. And the average home-cooked roast dinner has LOTS of fat. Will we ban roast dinners?

6). The foods restricted are often no more calorific than those permitted -- such as milk and fruit-juice drinks.

7). Tendency to weight is mostly genetic and is therefore not readily susceptible to voluntary behaviour change.

8). And when are we going to ban cheese? Cheese is a concentrated calorie bomb and has lots of that wicked animal fat in it too. Wouldn't we all be better off without it? And what about butter and margarine? They are just about pure fat. Surely they should be treated as contraband in kids' lunchboxes! [/sarcasm].

9). And how odd it is that we never hear of the huge American study which showed that women who eat lots of veggies have an INCREASED risk of stomach cancer? So the official recommendation to eat five lots of veggies every day might just be creating lots of cancer for the future! It's as plausible (i.e. not very) as all the other dietary "wisdom" we read about fat etc.

10). And will "this generation of Western children be the first in history to lead shorter lives than their parents did"? This is another anti-fat scare that emanates from a much-cited editorial in a prominent medical journal that said so. Yet this editorial offered no statistical basis for its opinion -- an opinion that flies directly in the face of the available evidence.

Even statistical correlations far stronger than anything found in medical research may disappear if more data is used. A remarkable example from Sociology:
"The modern literature on hate crimes began with a remarkable 1933 book by Arthur Raper titled The Tragedy of Lynching. Raper assembled data on the number of lynchings each year in the South and on the price of an acre's yield of cotton. He calculated the correla-tion coefficient between the two series at -0.532. In other words, when the economy was doing well, the number of lynchings was lower.... In 2001, Donald Green, Laurence McFalls, and Jennifer Smith published a paper that demolished the alleged connection between economic condi-tions and lynchings in Raper's data. Raper had the misfortune of stopping his anal-ysis in 1929. After the Great Depression hit, the price of cotton plummeted and economic condi-tions deteriorated, yet lynchings continued to fall. The correlation disappeared altogether when more years of data were added."
So we must be sure to base our conclusions on ALL the data. But in medical research, data selectivity and the "overlooking" of discordant research findings is epidemic.


1 comment:

Anonymous said...

You're right. The warriors always want to make you believe that there are foods that fight prostate cancer. It's as if cutting out fat is the latest treatment on prostate cancer.