The economic impact of chronic illness

Mar 27 JDN 2459666

This topic is quite personal for me, as someone who has suffered from chronic migraines since adolescence. Some days, weeks, and months are better than others. This past month has been the worst I have felt since 2019, when we moved into an apartment that turned out to be full of mold. This time, there is no clear trigger—which also means no easy escape.

The economic impact of chronic illness is enormous. 90% of US healthcare spending is on people with chronic illnesses, including mental illnesses—and the US has the most expensive healthcare system in the world by almost any measure. Over 55% of adult Medicaid beneficiaries have two or more chronic illnesses.

The total annual cost of all chronic illnesses is hard to estimate, but it’s definitely somewhere in the trillions of dollars per year. The World Economic Forum estimated that number at $47 trillion over the next 20 years, which I actually consider conservative. I think this is counting how much we actually spend and some notion of lost productivity, as well as the (fraught) concept of the value of a statistical life—but I don’t think it’s putting a sensible value on the actual suffering. This will effectively undervalue poor people who are suffering severely but can’t get treated—because they spend little and can’t put a large dollar value on their lives. In the US, where the data is the best, the total cost of chronic illness comes to nearly $4 trillion per year—20% of GDP. If other countries are as bad or worse (and I don’t see why they would be better), then we’re looking at something like $17 trillion in real cost every single year; so over the next 20 years that’s not $47 trillion—it’s over $340 trillion.

Over half of US adults have at least one of the following, and over a quarter have two or more: arthritis, cancer, chronic obstructive pulmonary disease, coronary heart disease, current asthma, diabetes, hepatitis, hypertension, stroke, or kidney disease. (Actually the former very nearly implies the latter, unless chronic conditions somehow prevented one another. Two statistically independent events with 50% probability will jointly occur 25% of the time: Flip two coins.)

Unsurprisingly, age is positively correlated with chronic illness. Income is negatively correlated, both because chronic illnesses reduce job opportunities and because poorer people have more trouble getting good treatment. I am the exception that proves the rule, the upper-middle-class professional with both a PhD and a severe chronic illness.

There seems to be a common perception that chronic illness is largely a “First World problem”, but in fact chronic illnesses are more common—and much less poorly treated—in countries with low and moderate levels of development than they are in the most highly-developed countries. Over 75% of all deaths by non-communicable disease are in low- and middle-income countries. The proportion of deaths that is caused by non-communicable diseases is higher in high-income countries—but that’s because other diseases have been basically eradicated from high-income countries. People in rich countries actually suffer less from chronic illness than people in poor countries (on average).

It’s always a good idea to be careful of the distinction between incidence and prevalence, but with chronic illness this is particularly important, because (almost by definition) chronic illnesses last longer and so can have very high prevalence even with low incidence. Indeed, the odds of someone getting their first migraine (incidence) are low precisely because the odds of being someone who gets migraines (prevalence) is so high.

Quite high in fact: About 10% of men and 20% of women get migraines at least occasionally—though only about 8% of these (so 1% of men and 2% of women) get chronic migraines. Indeed, because ti is both common and can be quite severe, migraine is the second-most disabling condition worldwide as measured by years lived with disability (YLD), after low back pain. Neurologists are particularly likely to get migraines; the paper I linked speculates that they are better at realizing they have migraines, but I think we also need to consider the possibility of self-selection bias where people with migraines may be more likely to become neurologists. (I considered it, and it seems at least as good a reason as becoming a dentist because your name is Denise.)

If you order causes by the number of disability-adjusted life years (DALYs) they cost, chronic conditions rank quite high: while cardiovascular disease and cancer rate by far the highest, diabetes and kidney disease, mental disorders, neurological disorders, and musculoskeletal disorders all rate higher than malaria, HIV, or any other infection except respiratory infections (read: tuberculosis, influenza, and, once these charts are updated for the next few years, COVID). Note also that at the very bottom is “conflict and terrorism”—that’s all organized violence in the world—and natural disasters. Mental disorders alone cost the world 20 times as many DALYs as all conflict and terrorism combined.

The cost of illness

Feb 2 JDN 2458882

As I write this I am suffering from some sort of sinus infection, most likely some strain of rhinovirus. So far it has just been basically a bad cold, so there isn’t much to do aside from resting and waiting it out. But it did get me thinking about healthcare—we’re so focused on the costs of providing it that we often forget the costs of not providing it.

The United States is the only First World country without a universal healthcare system. It is not a coincidence that we also have some of the highest rates of preventable mortality and burden of disease.

We in the United States spend about $3.5 trillion per year on healthcare, the most of any country in the world, even as a proportion of GDP. Yet this is not the cost of disease; this is how much we were willing to pay to avoid the cost of disease. Whatever harm that would have been caused without all that treatment must actually be worth more than $3.5 trillion to us—because we paid that much to avoid it.

Globally, the disease burden is about 30,000 disability-adjusted life-years (DALY) per 100,000 people per year—that is to say, the average person is about 30% disabled by disease. I’ve spoken previously about quality-adjusted life years (QALY); the two measures take slightly different approaches to the same overall goal, and are largely interchangeable for most purposes.

Of course this result relies upon the disability weights; it’s not so obvious how we should be comparing across different conditions. How many years would you be willing to trade of normal life to avoid ten years of Alzheimer’s? But it’s probably not too far off to say that if we could somehow wave a magic wand and cure all disease, we would really increase our GDP by something like 30%. This would be over $6 trillion in the US, and over $26 trillion worldwide.

Of course, we can’t actually do that. But we can ask what kinds of policies are most likely to promote health in a cost-effective way.

Unsurprisingly, the biggest improvements to be made are in the poorest countries, where it can be astonishingly cheap to improve health. Malaria prevention has a cost of around $30 per DALY—by donating to the Against Malaria Foundation you can buy a year of life for less than the price of a new video game. Compare this to the standard threshold in the US of $50,000 per QALY: Targeting healthcare in the poorest countries can increase cost-effectiveness a thousandfold. In humanitarian terms, it would be well worth diverting spending from our own healthcare to provide public health interventions in poor countries. (Fortunately, we have even better options than that, like raising taxes on billionaires or diverting military spending instead.)

We in the United States spend about twice as much (per person per year) on healthcare as other First World countries. Are our health outcomes twice as good? Clearly not. Are they any better at all? That really isn’t clear. We certainly don’t have a particularly high life expectancy. We spend more on administrative costs than we do on preventative care—unlike every other First World country except Australia. Almost all of our drugs and therapies are more expensive here than they are everywhere else in the world.

The obvious answer here is to make our own healthcare system more like those of other First World countries. There are a variety of universal health care systems in the world that we could model ourselves on, ranging from the single-payer government-run system in the UK to the universal mandate system of Switzerland. The amazing thing is that it almost doesn’t matter which one we choose: We could copy basically any other First World country and get better healthcare for less spending. Obamacare was in many ways similar to the Swiss system, but we never fully implemented it and the Republicans have been undermining it every way they can. Under President Trump, they have made significant progress in undermining it, and as a result, there are now 3 million more Americans without health insurance than there were before Trump took office. The Republican Party is intentionally increasing the harm of disease.