Increasing HALE

HALE is the cleverly appropriate acronym for Health-Adjusted Life Expectancy, a fancy way of saying how many years people can live in good health.

As I noted in my recent article on U.S. birth rates, the increase in Americans’ life expectancy has not been matched by increases in HALE:

Only two-thirds of Americans ages 55–64 are in the workforce. In part, this can be blamed on how little progress has been made in how many years they can expect to live in good health — to use the jargon, their health-adjusted life expectancy (HALE). This failure goes some way to explaining why only about a fifth of over-65s are working (of whom just under 40 percent are part-time). . . .

The HALE data are a reminder that Americans are not known for taking care of themselves, but once again, our species’ inventiveness is throwing us a life buoy. Remarkable pharmaceutical advances, including but not confined to GLP-1s, should boost HALE and the size of the potential workforce, and also, while they’re at it, reduce the pressure that extended longevity puts on Medicare.

I subsequently wrote about other encouraging developments that have taken place:

There have been hopes that GLP-1s could be a treatment for Alzheimer’s. It now seems more likely that their effect is preventative rather than braking or restorative.

Preventative is, of course, still good!

Interestingly:

it appears that the incidence of Alzheimer’s may be falling. There has been (and there will continue to be) an increasing number of cases. But that is an absolute number, reflecting the aging of the population.

And then yesterday I noticed this on X from D. K. Thompson:

Super weird, and potentially wonderful. We now have several natural experiments suggesting that the shingles vaccine significantly reduces dementia risk, or delays dementia risk, potentially by suppressing reactivation of the underlying virus, which can linger in nerve tissue and cause brain damage.

There may be some correlation/causation issues at play (do the sort of people likely to get vaccinated have a head start?) but these “natural experiments” suggest that that often reasonable explanation may be less relevant than usual.

Nina Bai touched on this (and more) in a 2025 article for Stanford Medicine’s News:

Some extracts:

 In a new study led by Stanford Medicine, researchers analyzing the health records of Welsh older adults discovered that those who received the shingles vaccine were 20% less likely to develop dementia over the next seven years than those who did not receive the vaccine.

The remarkable findings, published April 2 in Nature, support an emerging theory that viruses that affect the nervous system can increase the risk of dementia. If further confirmed, the new findings suggest that a preventive intervention for dementia is already close at hand.

There’s more:

In a follow-up study published Dec. 2 in Cell, the researchers found that the vaccine may also benefit those already diagnosed with dementia by slowing the progress of the disease.

But how about the correlation/causation issue?

Well:

Previous studies based on health records have linked the shingles vaccine with lower dementia rates, but they could not account for a major source of bias: People who are vaccinated also tend to be more health conscious in myriad, difficult-to-measure ways. Behaviors such as diet and exercise, for instance, are known to influence dementia rates, but are not included in health records.

But then turn to Wales. In 2013, it was decided that from September 1, that year,

anyone [living in Wales] who was 79 on that date was eligible for the vaccine for one year. (People who were 78 would become eligible the next year for one year, and so on.) People who were 80 or older on Sept. 1, 2013, were out of luck — they would never become eligible for the vaccine.

“Our” NHS is what it is.

But what that meant was that a comparison could be made between those eligible for the vaccine and those who were not, because, according to Pascal Geldsetzer, the author of the study:

“We know that if you take a thousand people at random born in one week and a thousand people at random, born a week later, there shouldn’t be anything different about them on average. . . .”

The same proportion of both groups likely would have wanted to get the vaccine, but only half, those not yet 80, were allowed to by the eligibility rules. . . .

By 2020, one in eight older adults, who were by then 86 and 87, had been diagnosed with dementia. But those who received the shingles vaccine were 20% less likely to develop dementia than the unvaccinated.

Moreover, the benefits seemed to include slowing the progress of the disease for those who already had it (or were later to get it).

The Wales findings have been replicated elsewhere.

Dementia is a cruel disease, so this may be tremendous news. As shingles is no fun anyway, for those at risk to get the two shots necessary (these days) for the vaccine to be fully effective seems (not medical advice, please consult your doctor) wise to me. Full disclosure: I am the “survivor” of a chickenpox party in the 1960s and was duly vaccinated against shingles a few years back. This was because chickenpox and shingles are caused by the same virus. It remains within you even after recovery from the former and can reemerge years later as the latter.

The boost to HALE resulting from reductions either in dementia or in its progression ought also to be good news for Medicare costs and, in that it increases the number of older people able to work, social security.

As it is (and as I noted in my article):

Labor participation rates among U.S. over-65s are increasing and are above the OECD average, but it’s hard not to think that they could be higher — if not now, at least in time. About a third of Americans between the ages of 65 and 69 toil on, as do one in five of those between 70 and 74.

Even now:

Americans who make it to 60 can probably enjoy another 17 to 18 years in which they are in respectable shape. Increasing the “core” retirement age to 70 from 67 (which is only two years higher than its Depression-era starting point of 65) could, depending on how it is structured, make a considerable dent in the Social Security deficit, even more so if additional hikes are tied to a lengthening in HALE. The argument for pushing the age up at least some of the way and with tweaks to help out poorer retirees is theoretically irresistible, but support for that is not there. Judging by polling, propping up the system with higher taxes (ideally payable by someone else) would be a more popular option. Surprise!

Enter Bernie Sanders. . . .