Tag Archives: health

can OR reduce health disparities?

I am enjoying the Virginia Health Equity Conference.  It’s hard not to believe that operations research can be used to improve public health.

I particularly enjoyed Dr. Howard Frumkin’s keynote about public health and the built environment. His talk was particularly inspiring for operations researcher. We spend almost all of our time in built environments (home, school, work, transportation, parks), and there is an enormous body of research that suggests that our environment is a strong predictor of our health. Our built environment is the result of a series of decisions, some of which can be the result of good operations research and mathematical modeling. A good built environment offers a wide portfolio of public health benefits. Dr. Frumkin listed several opportunities for operations research modeling to improve our built environment (and in turn, public health), including:
• Investigating where to locate schools (perhaps using decision analysis),
• Improving school bus routes that are also safe (Safe Routes), including walking school bus routes (using network design),
• Improving and analyzing transportation networks in urban sprawl regions, which are plagued with low connectivity and low population density (this leads to a host of problems such as reliance on vehicles, low rates of physical exercise, poor access to emergency medical vehicles, etc.).
• Locating trees and green space in urban areas to “cover” poor neighborhoods.

Dr. Frumkin stressed that many of these decisions are generally not made by public health people (perhaps some can be made by operations researchers).


more to come on health care

I apologize for being offline for the past month. Between illnesses, weddings, and the start of the school year, I cut back on blogging and twitter. I finally feel like I’m back into the swing of things.

I am looking forward to the Virginia Health Equity Conference later this week. Although the conference will mainly be attended by medicine and public health people, I hope to blog about health care during the conference. So keep an eye on the blog.  You can follow the conference twitter feed here.

I have been closely following the national debate surrounding health care and health insurance. Although it seems like the issue is mainly a macro-economics issue, I really do think that OR has a lot to offer, particularly in predicting the costs and benefits of treatment and care. But I see so much misinformation (sometimes well-meaning people with the wrong information, and sometimes more sinister ulterior motives) that I easily get discouraged about having a rational, quantitative discussion using OR methodologies.

Last week, I tried discussing some of the health care issues in my class (probability and statistics for engineers). After introducing Bayes rule, I illustrated why it implies that preventive medicine costs so much, in general. I think the discussion backfired. David Brooks explains it better [podcast link here]–when I try, I come off sounding like a an insensitive monster that wants to deny people health care. Really, I just want good numbers to support the debate so we can make good decisions. I’m not sure what the answer is, because I have no idea what the facts are yet. I hope OR is instrumental in providing the facts.

change the drinking age using OR

Underage college students drink. A lot. OR may be able to help.

Ben Fitzpatrick at Loyola Marymount University gave a talk here on Friday about modeling college student drinking habits using mathematical tools. It was entitled “Ecological Systems Modeling of College Drinking,” and it was one of the most engaging talks I have seen in awhile.

Forty-two percent of college students confess to binge drinking, which correlates highly with several forms of violence. Individual interventions are not very successful at curbing drinking problems, but community policies on the aggregate level show promise. Can mathematical modeling be used to predict whether changing the drinking age is a good idea? The premise is that college campuses are relatively homogenous (compared to metropolitan areas), so the resulting model may be useful for policy-making.

Fitzpatrick applied statistical models, dynamical systems, and differential equations that compartmentalized the college population into several groups. His approach uses the fact that people overestimate how frequently their peers engage in risky behaviors (e.g., smoking, drinking). The higher this misperception, the more likely students are to engage in binge drinking. The Social Norms Marketing Research Project provided him with four years of data from 32 schools to estimate misperception. Linear regression was used to estimate some of the parameters needed for Fitzpatrick’s model, and it worked fairly well (R^2 > 0.99 for several parameters).

One model incorporated social interactions (e.g., peer pressure) and social norms/perceptions using a network model (similar to the SIR model used by epidemiologists) to estimate how social interactions could increase or decrease drinking problems. His simulations showed that as drinking misperceptions grow, more students engage in binge drinking (called heavy episodic drinking). I found this particularly interesting, since VCU is always distributing anti-drinking propaganda in the bathrooms (called the Stall Seat Journal, I kid you not), which in essence attempts to reduce misperceptions. Apparently, this is a good strategy for battling underage drinking.

When the drinking age goes down, the “wetness” level in campus goes up, since there are more legal ways to get alcohol. But the Amethyst hypothesis is that misperception goes down when the drinking level goes down (and wetness goes up), since it is easier to directly observe peer drinking activities. Fitzpatrick’s model suggests that results are more sensitive to alcohol availability than to misperception.

This seems to be an important first step in the debate about the drinking age. Before I commit to a policy position, I’d like to see more of these mathematical models to predict what would happen if the drinking age changed. Interestingly, research shows that binge drinking almost completely disappears after college. Maybe we should be trying to get students to finish their degrees in 4 years or less, rather than allowing them to take five or six years to finish?

John McCardle (of the Amethyst initiative and President Emeritus of Middlebury U) appeared on the Colbert Report (3/19/09) to talk about why the current drinking age of 21 is not working. Link.

how to optimize your health care dollars

The Chicago Tribune had an interesting article on how to spend less money on health care. Their advice: use fewer health care resources. The rationale is that the list of things that we know help us live longer is “pretty short.” So quit smoking, exercise, and only spend money on the essentials. Here is what they claim is the list of essentials:

•Skip the annual physical examination. “It’s an unnecessary expense,” said Dr. Ranit Mishori, a family physician who teaches at Georgetown University School of Medicine.

•If you have a cold or an upset stomach, ask if your doctor will do a phone visit. “There may be a charge, but it may be less than even the co-pay for an office visit,” [Dr. Emily] Gottlieb said.

•If your doctor proposes an expensive imaging procedure, such as an MRI for the pain in your knee, ask what it’s for. “If the outcome of the test won’t change the treatment plan, why do it?” Mishori said.

•Instead of a colonoscopy to screen for colorectal cancer, you could opt for an inexpensive test for blood in the stool. “If there’s something wrong, you can follow up with colonoscopy,” Mishori said.

•Consider having a mammogram every two years. “We don’t have any evidence that doing it every year is better than every other year,” [Dr. Ned] Calonge said.

•Ask if you can have a Pap test once every three years. “If you’re over 30 and have had three normal Paps in a row, that shouldn’t be a problem,” said Dr. Linda Hughey Holt, an obstetrician-gynecologist in Skokie. “Only women at increased risk for cervical cancer need annual Paps. And those who have had a total hysterectomy don’t need them at all.”

•Drop your health club membership and walk a mile a day instead. “We know that exercise is very important to prevent diabetes and heart disease,” Gottlieb said. “It’s also important for people who are depressed. But there’s no need for a trainer or a lot of fancy machines.”

•Ask about cheaper equivalents of your prescription drugs. Some chain pharmacies, including Wal-Mart and Target, have $4-a-month prescription plans for the most common generic drugs. You may be able to substitute lovastatin at $4 for Lipitor, which costs about $140.

•For dental work, continue regular checkups to avoid long-term, expensive problems. If you have good oral hygiene and no history of problems, you can consider increasing the intervals for cleanings and X-rays, some experts say. As a general rule, adults usually can delay cosmetic dentistry and orthodontia. But in children, “early orthodontia can save money later,” said Dr. Robert Sandusky of Evanston.

•Talk to your doctor about dropping your cholesterol medication altogether, especially if you’re over 85. The consequences of high cholesterol aren’t felt for 10 or 15 years, Gottlieb said, so pausing or even stopping treatment may not significantly affect your health.

•Insist that your health care providers use the latest operations research innovations so that they can provide the same level of service for less.

OK, so I made up that last item, but wouldn’t that be cool? Many economists have noted that we spend so much for health care in the US because we pay for unnecessary treatment. I don’t know enough to make a comment, but the list looked pretty reasonable to me. What do you think?

OR and the food system

A few weeks ago, I caught a couple minutes of a Michael Pollan interview (the Omnivore’s Dilemma) on Bill Moyers Journal. It was fascinating, but I was tired, so I turned the TV off and went to bed. I just got around to listening to the podcast. Pollan mentions several issues in the interview that have OR implications.

  1. Food is cheap in the US. But cheap food is very expensive when taking the whole system into account (food transportation, type II diabetes, other health problems). Looking at the whole system is necessary to understand the costs. Pollan claims that food processing requires 10 calories per calorie consumed(!)
  2. Food security is a big issue when our food system is centralized. It is easy to contaminate our food supply when so much food is processed in one location. This is not a new issue, but may have an OR solution. Lawrence Wein talked about the issue at the INFORMS annual meeting (Wein wrote a paper about botulism in the milk supply).
  3. Pollan is very critical of the school lunch program since it is used to get rid of food surpluses, which means that students are fed junk food. This really gets me riled up since my oldest child is almost old enough to start school. Pollan advocates spending $1 per student per day to increase the nutritional value in school lunches. Here’s the kicker. As part of the solution, a certain fraction of this extra $1 should be spent within 100 miles of the school in order to meet many social goals (increasing nutritional value of school, reviving the local economy, supporting local agriculture, reducing our dependence on the amount of fossil fuels to transport food all across the country). This sounds like an optimization problem!
  4. Pollan proposes a way to measure how healthy out diets are: the fraction of our meals that we cook ourselves. Discuss amongst yourselves. Looking at the fraction of our diet that comes from plants (as opposed to animals) could also a decent measure or looking at the fraction of our diet that is not made of corn by-products (corn syrup) eaten might be OK. On the other hand, a diet of all Fritos is 100% plant-based so it scores high in my first measure, but it is also 100% corn-based, so it scores low in my second measure. I think Pollan has me beat.

Pollan recommends starting a vegetable garden. Apparently during WWII, Eleanor Roosevelt was instrumental in the Victory Gardening program that encouraged people to start vegetable gardens at home. It is widely reported that at the end of WWII, 40% of the US food production came from these 20 million gardens. This is way better than “Freedom Fries.”

I started a garden this year. I built a raised garden bed and planted tomatoes, zucchini, green beans, eggplant, sweet potatoes, hot banana peppers, and butternut squash with various levels of success. It was easy and fun. Digging up sweet potatoes was more fun than I could have imagined (9 small plants yielded about a bushel of sweet potatoes). My cherry tomatoes were so delicious that I ate all of them right off of the plant (a few a day over the course of several weeks). It didn’t generate 40% of my food consumption, but it’s a good start.

Watch the Michael Pollan interview here.

contaminants in baby formula

As reported a few days ago, the FDA finally set the maximum safe level for melamine and cyanuric acid at 1 part per million each (after resisting setting a safety threshold in October). There is no safe level if both melamine and cyanuric acid are present. I just love the more complicated joint safety threshold. But I am underwhelmed by the FDA’s test results. Just two tests have positive results for melamine (0.137, 0.140 ppm) and three tests have positive results for cyanuric acid (0.247, 0.245, 0.249 ppm). While so many tests have zero melamine, and the ones that tested positive are well below the limit, I’d like to know a little more about the source and distribution of the contamination, since 6 babies died and 300,000 were hospitalized due to melamine contamination in China.

The variance is for these things is important. The FDA issued concerns about tuna after Consumer Reports noted that about 6% of light-tuna samples tested by the FDA had much higher levels of mercury than the other 94% of light-tuna samples. The levels weren’t necessarily dangerous, but high variance = more uncertainty = more risk. I’d like to know that the melamine levels in baby formula has low variance. The fact that so many tests found no melamine is promising, but given that the contaminant is present, shouldn’t some kind of confidence interval be constructed to “prove” that formula is safe?

This whole melamine saga is yet another reason I support breastfeeding. You never know what contaminants are going to be present. Having said that, most women are not able to exclusively breastfeed for the recommended duration of at least one year (10.4% make it to 12 months without having to supplement with formula), so most babies will be getting formula. Mothers shouldn’t have yet another thing to worry about.