Junkfood Science: The most common source of unsound health interventions

January 01, 2008

The most common source of unsound health interventions

To the young math student visitors: Please be cautious of bias and those leading you to think a certain way, especially online pieces written by unidentified authors and those trying to sell you something. Go to original sources yourself. On the right hand sidebar, you'll find an obesity paradox series that may be of help to you as you begin questioning and thinking critically about weight, especially the article on statisticulation [here] since you're looking at statistics. To better understand health risk factors, you'll find a helpful article here. There is also a Google search tool at the bottom of the sidebar, where you can search by topics. You might find articles on "fair test" especially helpful to better understand what scientists and medical professionals know are required to soundly test a research hypothesis so that the results are not confounded by methodological bias. You'll find my actual bio here. Best of luck to you in your studies.

Yellow teeth is a risk factor for lung cancer. Of course, the soundest evidence clearly shows us that yellow teeth is not the cause of lung cancer, so no one would seriously suggest extracting healthy teeth to prevent lung cancer.

Instead, the only medical treatments and preventive health care that would ever be taken credibly, or have any hope of demonstrating effectiveness, are those directed towards the real causes for premature death and diseases. Even then, the risks of any intervention are carefully weighed: scientists and doctors balance the actual benefits for real people in their care against the potential harm of a treatment. It’s that “first do no harm” adage that has long guided medicine.

So, we look to see if a treatment positively affects actual clinical outcomes — important and indisputable changes, like premature deaths, eradication of a disease pathogen or fewer bone fractures. It doesn’t matter if it changes some surrogate measure, like a lab test result or other measure. No one wants to hear that “the treatment ‘worked’, but the patient died.” In other words, beware of false surrogate endpoints. We want our doctors to treat actual health issues and for our country’s limited healthcare resources to go for things that will make actual differences.

This all sounds logical, doesn’t it? But applying such basic concepts can sometimes be hard in real life.

The difficulty often lies in failing to understand a most basic principle in research: “correlations do not equal causation.” It is, in fact, the single most common source of unsound health interventions. It’s an especially hard concept to grasp when a correlation, even when it’s not tenable, falls in line with something one has come to believe is a cause.

What is a risk factor? A correlation. A risk factor is not a cause for a disease and it certainly isn’t a disease itself.

The most notable examples of failing to understand this basic scientific principle — and failing to base medical care on actual health problems — that I’ve seen in my thirty years of nursing and research is in the care of fat people. Especially if the patient is a fat woman.

As we’ve seen, obesity itself is not the cause of premature deaths. At the most extremes it can be associated with poorer outcomes. It can be a risk factor. The popular phrase “Obesity is deadly” is another example of turning a correlation into a causation.

Every study to date, however, has consistently shown underweight (another risk factor) to be a far more life-threatening (even when controlling for cancer, chronic diseases and smoking), yet it receives far less attention in media and condemnation in the medical literature. Even the most “morbidly obese” women live longer than “normal weight” men, yet maleness isn’t the focus of rampant attention, either.

The fattest women (and men) are, however, more likely to be associated with confounding factors that can adversely affect health, like disparities in socioeconomic status and healthcare access, side effects of prescriptions for health indices or weight loss drugs and diets, less cancer screenings, social discrimination and life stresses, and delayed and poorer healthcare. As that recent British investigative report on maternal deaths found, for instance, medical care often fails the heaviest women when their symptoms are blamed on their weight and go untreated or not treated until it’s too late.

When two patients present with identical health issues or symptoms, why do some providers focus on weight when caring for the fat person, rather than address their symptoms as they would the thinner patient? A multitude of assumptions are also often made about them and their lifestyles, solely on the basis of their size. “Just lose weight!” becomes the answer to any condition that afflicts a fat patient.

There are countless stories of fat people, especially women, seeking medical care and told to lose weight, regardless of the medical concern. Everything has been blamed on their weight. A thin person coming to the doctor for rheumatoid arthritis, gerd, infertility or hypertension, for instance, would never be prescribed a weight loss diet or, worse, bariatric surgery on a healthy digestive tract. Yet fat people are every day.

So why the focus on weight?

For some caring healthcare professionals, maybe it is that they continue to misunderstand correlations, and have come to believe so strongly in obesity as a risk factor, that they think of it as a cause, and confirmation bias prevents them from even seeing or considering evidence to the contrary.

But, sadly, there is also an undeniable issue of prejudice against fat people, especially fat women. As Rudd research has well-documented, healthcare professionals hold the same anti-fat attitudes, prejudices and disdain of fat people as the rest of society, and these negative professional attitudes adversely impact clinical judgment, screening and diagnosis, and the care fat people receive.

These are uncomfortable issues to confront, especially for healthcare professionals who entered medicine because they care about people. But recognizing them is crucial to making changes that will improve care and reduce quality of care disparities.

Here are just two letters sent into JFS by readers who requested their stories be printed and shared with doctors, in hopes they might help open minds and hearts. These are not isolated incidents. There are hundreds more stories more just like these that this author has heard for years.

As you read these, ask yourself: If these women had been pretty and thin, would their symptoms have been blown off and blamed on their weight? Is this the care a thin woman would have received?

Is this the care a thin woman would have received?

Hint: Neither primary hyperaldosteronism or thoracic aortic aneurysms are caused by being fat, nor is weight loss a recognized treatment.

The first letter comes from KB who writes:

My mum called me last night. Her latest labwork showed her kidney function is now down to 23%...any lower and we're talking dialysis. My mother's kidneys are failing due to sustained, uncontrollable high blood pressure. What's really crappy about this is it could have been prevented. Not her by her losing weight, by exercising more, or by dieting; but if doctors had taken her symptoms seriously and done their jobs many years ago.

For years, my mother's BP was high and meds were given, along with shame and blame doled out by the medical profession. One specialist actually said to her: “You wouldn't have high blood pressure if you got off your fat ass and stopped eating bon bons.”

This went on for over ten years until a nephrologist who really cared did some digging and diagnosed Mum with a condition called Primary Hyperaldosteronism or Conn Syndrome. This is a relatively rare condition where tumours either on your pituitary gland or your adrenal glands (which sit on your kidneys) pump out too much stress hormone, sending your body into stress mode, and sending your BP up.

Ten years after her symptoms began, those tumours were finally removed, but the damage was done. If intervention is early, the symptoms can be reversed, but it was too late for her. So slowly over the past four years, her health has deteriorated to the point where she barely functions.

I'm so angry at the medical profession, and it's now happening to me. I'm 38 and was diagnosed with high BP seven years ago. Just last month a doctor, who happened to be covering for my GP, finally said to me: “There is something medically wrong with you, it's not because you're fat, and you should have been investigated when this first came up.”

I am awaiting tests now, but I'm scared I'll wind up like my mother. I hate doctors. I hate what they've done to my mother and to other fat members of my family. I don't know how to get them to change their thinking.

Guess I just needed to vent. I'd love a way to send this to physicians, to open their minds and ask them to please stop making assumptions.

The second letter comes from JK, who also wrote about her mother:

My mom's always been large. She didn’t eat any more than anyone else. Everyone in my family on my mom's side has always been large, in fact. As far back as I can remember, everyone made life hell for those in the fat side of my family — things none of us needed to be put through. Now, I’ve come to know we were all worthy of being loved for who we were. I wish my mom had gotten that, too, but unfortunately she never got her head around the idea that being fat wasn’t a moral failing. It used to kill me later in life, when she became disabled and I would take her to doctor appointments, to see her get the sort of verbal abuse about her weight she did, while her very real medical problems went unaddressed. This was a brave, strong woman who went back to school, became a nurse and raised a kid by herself after my dad was gone. She didn’t deserve to be forced to grovel and beg for care.

She had very real health issues, diagnosed with Rheumatoid Arthritis and Lupus, and developed peripheral neuropathy. She lived in constant pain. Because of the autoimmune problems, even a small scratch could become a big deal. And what was she told with all of this? “Get up and move around more, you'll feel better." She worked as a surgical nurse for 15 years and I’m sure I don’t have to tell you about the physical stresses with that job on your feet all day. The amount of NSAIDs she had to take to function was painful to watch. Still, she had frequent episodes where her joints would swell and her skin would turn red, she'd be in pain and exhausted, and through it all she dragged herself to work every day.

Her blood pressure had been normal all her life but it suddenly became elevated after she retired. She was put on blood pressure meds.

We started noticing not long after Thanksgiving, 1992, that she seemed a bit disoriented. She wasn't feeling well, wasn't eating well, having noticeable edema in her legs, and her face became pale, with a faint grayish tinge. I kept asking her to make an appointment with the doctor and she didn't want to go. She didn't like the doctor under her senior medicare plan because he hassled her about her weight and her smoking. She wouldn't quit because she was terrified of gaining even more weight. Christmas Eve she had trouble recognizing my brother and his wife when they came for dinner. We tried to get her to go to the doctor, but she kept saying: “All he'll do is bitch at me about being fat, I can get that from my mother for free.” (Her mother was larger than any of us and died in 2002 at the age of 98.)

By Sunday evening she felt horrible, couldn't catch her breath, was congested, nauseous, dizzy and her heart was racing. I took her to the ER. There, she admitted that she’d run out of her Synthroid two weeks earlier and hadn't told anyone she didn’t have the money to get more. The doctor was done with the interview at that point, gave her some samples and a prescription, said that she’d just gained weight and that was why she was having trouble breathing, and sent her home.

She didn't improve over the course of the week. The following Monday, she woke up at 4am and told me she was experiencing tearing chest pain. She was crying and coughing and asked me to call 911. She wasn't a cryer and she would never have let me call 911 unless it were an emergency.

Once at the ER of one of the accredited trauma centers in the county, they did an EKG and said it was normal aside from being tachycardic (fast), which they decided was because of her weight and being anxious over the chest pain. Her leg edema was severe; she was coughing and could barely catch her breath; her lips, fingernails and the skin had a slight bluish tint and her oxygen saturation was 73%.

When she was asked to rate her pain on a scale of 1-10 she rated it an 8. This was a woman who WALKED on a fractured leg with help. This was a woman who worked with RA, even when her joints were swollen. She had this insanely high pain tolerance. If she said 8 she had to be in severe pain for her.

They decided she had pneumonia and admitted her for 24-hour observation. They gave her lasix for the edema and aspirin for her pain. They wouldn’t do any imaging or an ultrasound to try to determine the source for her severe pain. Later that day she was still having a lot of discomfort in her arms and upper back. The doctor wouldn't even bother to talk to the family. Mom told me he'd given her a diet and said that all of her symptoms were because of her weight and that she just had to lose weight and quit smoking....

They called me at 5 the next morning... when I got there they told me she'd gone into arrest and they hadn't been able to revive her. I signed for the autopsy. The doc called me the next day with the results: She had a 7cm transverse split on her ascending aorta with dissection. He felt she'd had the dissection for at least a year if not more, given the size of the aneurysm itself. He wasn't sure it would have been operable by the time she came in, and had probably begun leaking by the time she was developing symptoms before Christmas.

Her father — who was of normal weight — had died of the same thing, at age 63.

She was only 64. At the time of her autopsy she was 5'7" and weighed 246 lbs. There was this attitude that her death was her own fault for being fat, when the truth was her death was due to a condition that has a large genetic component and could have been treated. Perhaps, had her symptoms not been dismissed weeks or a year earlier, her death could have been prevented. I can't help but wonder if she'd been 146 instead of 246, if she'd have received more appropriate care than aspirin, lasix and a diet.

There are hundreds upon hundreds of stories like these, year after year. The highest extremes of ‘obesity’ in population studies may be associated with higher risks for premature death than ‘normal’ weight people. But, this correlation is not a cause. Disparities in healthcare is just one of many confounding factors.

As long as correlations continue to be made into causes and treatments continue to be focused on a risk factor, stories of needless suffering and poor outcomes will continue, too.

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