Hypertension is Extremely Important, Tractable, and Neglected

[Marshall]

Hypertension (high blood pressure) is:

• the risk factor that causes the most deaths and second highest number of DALYs worldwide.

• easily treated with generic drugs; intervention programs can approach the cost-effectiveness of much more popular causes.

• barely mentioned by the EA community and badly neglected by global health donors.

Let’s take a closer look.

Hypertension is extremely important

According to the latest Global Burden of Disease report, hypertension causes the most global deaths (10.8 million per year) and second-most DALYs of any risk factor. The burden of hypertension grows as more countries go through the demographic transition and change their lifestyles. There’s enormous room for improvement because the vast majority of people worldwide who have hypertension aren’t aware of it and only a small fraction of people who have hypertension are being treated.

Hypertension is tractable

Hypertension is very treatable and treatment is cost-effective

Hypertension is treated by (drumroll) reducing blood pressure. Since high blood pressure itself causes disease by damaging the cardiovascular system, treatment with medication is very effective for preventing mortality and morbidity. Almost all cases of hypertension are easily treated with low-cost generic drugs. Control rates are highest when standard treatment protocols are followed, and such protocols can be implemented nationwide in countries that have national health systems. There are certainly challenges: the drugs need to get to the patients in an uninterrupted supply, blood pressure control needs to be confirmed, and patients need to keep taking the medications, but these are all issues that health systems and health professionals have overcome with other diseases.

There’s also good evidence that treatment programs can be cost-effective. A review of hypertension control interventions reports a handful of studies with costs of less than $100 per DALY averted. This cutoff is sometimes referenced as a benchmark for the cost effectiveness of insecticide treated bednet programs. Many of the hypertension control interventions reviewed were more expensive (even by orders of magnitude). However, this is true of any global health intervention in any disease area. For example, different malaria control programs will inherently have wide ranges of cost effectiveness.

Regardless of the exact numbers today, experts in the field contend that hypertension control investments can be highly cost-effective. Keep in mind the second-order effects: saving lives through low-cost hypertension control can substantially reduce the cost of caring for cardiovascular disease patients. More investment and research is needed to find and scale up the most cost-effective control strategies.

Hypertension control will become more cost-effective

We should have every reason to believe that, with some concerted effort and investment, hypertension control programs will become much more cost-effective than they are now. First, all of the drugs needed are generic, but in many countries they are overpriced relative to production costs: driving down drug prices will increase cost-effectiveness. Second, with such high neglectedness, the most cost-effective control strategies just haven’t been identified and scaled up. While not every country is the same, with more focus on hypertension as a cause area, lessons learned can move laterally between hypertension control programs to further reduce costs.

EAs often talk about “room for growth.” It’s hard to find a better cause area than hypertension in this regard because the world is starting from such a low base. The vast majority of people living with hypertension are not currently being treated. Any additional funding can be used to set up hypertension control programs in new places (or improve existing programs). There’s also a ton of potential for synergy with governments, who invest in hypertension control regardless of what donors do.

Hypertension is badly neglected

The EA community barely mentions hypertension. We can use a quick but crude methodology to demonstrate this. I used Google search to find the number of pages on the EA forum that mention each term. As of May 12, 2022, the word “hypertension” appears on fewer than 25 pages, and in most of those, it’s incidental to some other point. By contrast, “malaria” appears on more than 1,500 pages and “longtermism” appears on more than 2,600 pages. Keep in mind that malaria is responsible for about 20% of the DALYs of hypertension. It’s also barely mentioned in EA books. For example, in “Doing Good Better,” a quick Google Books search reveals that “malaria” appears on 36 pages; “hypertension” appears on zero pages.

There’s plenty of existing research showing that the global aid community also neglects hypertension (and noncommunicable diseases more broadly). According to one estimate, less than 3% of global health aid goes towards noncommunicable diseases.

Causes of neglected causes

It’s interesting to speculate why hypertension is so terribly unpopular. I think there are a few reasons.

1. Visibility—hypertension is the “silent killer.” Many people have no symptoms until they have a heart attack or stroke, and then it’s too late.

2. Ageism—it’s a disease of middle age and beyond, and many of the “foot soldiers” of EA and global health are young people. They may not be faced with hypertension in their daily lives; perhaps the prospect of saving old lives even feels a bit prosaic.

3. Failure to attribute—hypertension is a risk factor that’s not listed as a cause of death in and of itself. As a result, we have to dig a bit deeper to find and understand its effects on global suffering and disease.

I want to emphasize, however, that hypertension is very treatable and tractable, and it’s better to treat the root cause of the disease before it develops rather than just manage the disease when it has developed.

What to do next

My main point is that hypertension deserves more attention from the EA community. Whether or not you find the arguments here convincing, here are some possible next steps.

• Conduct cost-effectiveness and expected-value research into this problem. I’ve referenced DALYs here because that is what’s published, but the EA community has its own methods.

• Debate this cause area and share your own thoughts. Why are the arguments made here wrong, or right?

• Look for promising projects that have potential for scale or more rigorous study. What is already out there? Where can some investments be made?

Closing thoughts

I want to close by addressing one potential critique:

“OK, so there are a lot of old people who die from diseases caused by hypertension, but as of today, there is no investment-ready project in this area that meets my high standards of cost effectiveness and room for growth. I’m not wasting my Dogecoin on this.”

To which I would say this:

“Imagine that you have a salt shaker filled up with longtermist thinking. It gives you the power to simultaneously be rational, data-driven, and speculative. It allows you to imagine all kinds of things that haven’t happened yet, make predictions about the future, and believe you can change the extremely distant future for the better. Please take that salt shaker and apply a tiny dash of its contents to your analysis of this problem.”

It’s true that, as of today, there are no GiveWell charities that work on hypertension, but it’s a strong candidate for hits-based giving. If we want to expand the number of ways to save and improve lives, which could be a great way to broaden the appeal of the EA community, hypertension seems like a good place to start.

[Marcel D]

I support thinking about/​discussing neglected problems like this, and it might be the case that there is serious room for improvement here. However, I do want to briefly push back on your selective reporting of the most favorable $/​DALY estimate:

There’s also good evidence that treatment programs can be cost-effective. A review of hypertension control interventions reports a handful of studies with costs of less than $100 per DALY averted. This cutoff is sometimes referenced as a benchmark for the cost effectiveness of insecticide treated bednet programs.

When I read the study (Table 4), it seemed that most of the relevant estimates were multiple times over the $100/​DALY mark (e.g., 200–1000).

This isn’t a terrible problem, but I would definitely prefer that posts like this more explicitly acknowledge/​emphasize that most of the studies were not that positive. That was only the first claim made here that I investigated (admittedly because it seemed like one of the most concerning), so it leaves me a bit more skeptical as to the overall post. I’m also a bit unsure/​skeptical as to how effectively the programs would scale and whether the costs incorporate certain administrative costs that might be incurred.

Still, like I said it might be the case that even with that being acknowledged there are still some interventions really worth supporting (or at least investigating further).

[Marshall]

Thanks, I accept the critique. I do think it’s clear from the full post, however, that I’m just making the case for greater focus by the community, rather than saying this is a closed case. I also state clearly in the same paragraph that other studies had much higher cost estimates.

[Raphaël S]

How did you discover this cause area? Is there a way to automatically browse all diseases and associated daly and see the research effort associated with each disease?

[Gavin Bishop]

The WHO has some good rankings of disease burden. They have different rankings for DALYs, YLLs and YLD. For example, back and neck pain is globally the leading cause of years lived with disability, but neonatal conditions and ischaemic heart disease cause the most DALYs. I imagine you could combine this with some other table that quantifies research effort and another which quantifies investment in that particular cause area.

Does anyone know of a good place to find them?

[Tessa A 🔸]

I haven’t looked into this in detail (honest epistemic status: saw a screenshot on Twitter) but what do you think of the recent paper Association of Influenza Vaccination With Cardiovascular Risk?

Quoting from it, re: tractable interventions:

The effect sizes reported here for major adverse cardiovascular events and cardiovascular mortality (in patients with and without recent ACS) are comparable with—if not greater than—those seen with guideline-recommended mainstays of cardiovascular therapy, such as aspirin, angiotensin-converting enzyme inhibitors, β-blockers, statins, and dual antiplatelet therapy.

[Marshall]

Super interesting and thank you for sharing! A potential advantage of vaccination is that it does not require daily dosing (unlike hypertension medications), and of course, it has the benefit of also preventing illness. Would be interesting to see cost-effectiveness analyses for seasonal influenza campaigns.