A World without Public Health.

January 3, 2016
Twitter Facebook

I hope everyone has had a terrific holiday break. I wanted to start the year by taking a look at the success of public health, to illuminate how much poorer the world we live in would be without public health.

Improving the health of populations is the core ultimate goal of the academic health enterprise. Sometimes that goal seems pyrrhic, and I have in the past year commented a fair bit on the lives that could be saved by action on firearms, or perhaps less controversially, through better vaccination of populations.

However, over the past century, public health also has realized tremendous successes. We have much to learn, and perhaps celebrate, from the successes of the past. To that end, to start the year, we take a look at four of the triumphs of public health and their implications. We draw these four from the CDC’s Ten Great Public Health Achievements in the 20th Century and highlight advances related to tobacco, control of infectious disease, motor vehicle safety, and cardiovascular disease.

To articulate a frame, we ask the question: What would the world have looked like if we did not have success in each of these areas?

We start, perhaps inevitably, with the success of tobacco control in the United States in the 20th century. This success is attributable to many factors, including the enumeration of the health risks associated with smoking, the public health campaign to reduce consumption, and the changing of public norms towards smoking, and increased taxation. The rate of per capita cigarette consumption in the US in the 20th century is presented in Figure 1a, annotated with relevant events that contributed to this success.

Figure 1a – Tobacco consumption in the 20th Century, adapted from figure 1 in : Centers for Disease Control and Prevention (1999). Tobacco use--United States, 1900-1999. MMWR. Morbidity and mortality weekly report, 48(43)
Figure 1a
Tobacco consumption in the 20th Century, adapted from figure 1 in : Centers for Disease Control and Prevention (1999). Tobacco use–United States, 1900-1999. MMWR. Morbidity and mortality weekly report, 48(43)

Figure 1a shows clearly that the doubling of the federal cigarette tax, the Fairness Doctrine, and the Master Settlement Agreement were all key inflection points in our progress towards improved tobacco control. These are textbook examples of macrosocial drivers that were instrumental in improving population health.

But what if these efforts had not been implemented? What if public health had not achieved this success? We could ask what would have happened if some of those tobacco control efforts had failed—for example, what if the federal cigarette tax had not doubled, and the Fairness Doctrine and the Master Settlement Agreement had not been passed? We represent one version of this alternate reality in Figure 1b.

Figure 1b – Tobacco consumption in an alternate 20th Century, adapted from figure 1 in : Centers for Disease Control and Prevention (1999). Tobacco use--United States, 1900-1999. MMWR, 48(43)
Figure 1b
Tobacco consumption in an alternate 20th Century, adapted from figure 1 in : Centers for Disease Control and Prevention (1999). Tobacco use–United States, 1900-1999. MMWR, 48(43)

Figure 1b assumes extends the pre-existing trajectory but removes some of the key public health efforts that inflected the shape of the tobacco consumption curve. What would have been the implications of this alternate reality? We would estimate that the difference between the original and revised curve represents 451 cigarettes per capita on average annually between 1968 and 1997. We know that at an ecologic level, consumption of 3 million cigarettes is associated with one lung cancer death, and that the time lag between consumption and death is 35 years on average. Performing an area under the curve calculation, this would then mean an excess of 1,005,778 deaths from lung cancer between 2003 and 2032.

Now we move on to the control of infectious disease, another major advance of the 20th century, attributable to a combination of sanitation and hygiene improvements, the advent of antibiotics, and universal vaccination programs. The crude annual death rate attributable to infectious disease deaths in the United States is presented in Figure 2a, annotated with key events of import.

Figure 2a Infectious Disease Control in the 20th Century, adapted from figure 1 in Centers for Disease Control and Prevention (1999). Achievements in public health, 1900-1999: control of infectious diseases. MMWR, 48(29)
Figure 2a
Infectious Disease Control in the 20th Century, adapted from figure 1 in Centers for Disease Control and Prevention (1999). Achievements in public health, 1900-1999: control of infectious diseases. MMWR, 48(29)

In this case we ask not what would have happened if key public health actions never happened, but rather if they were simply delayed. In Figure 2b, we present an alternate version, where the initiation of widespread state health departments and the continuous use of chlorine were delayed by 10 to 20 years.

What would this have meant? We estimate, based on the difference between the above two curves, that this would translate into an excess of 21,651,243 infectious disease deaths between 1900 and 1995.

Figure 2b Infectious Disease Control in an alternate 20th Century, adapted from figure 1 in Centers for Disease Control and Prevention (1999). Achievements in public health, 1900-1999: control of infectious diseases. MMWR, 48(29)
Figure 2b
Infectious Disease Control in an alternate 20th Century, adapted from figure 1 in Centers for Disease Control and Prevention (1999). Achievements in public health, 1900-1999: control of infectious diseases. MMWR, 48(29)

No we move on to the decline in cardiovascular disease (including stroke, coronary heart disease, and other diseases of the heart), one of the hallmark health improvements of the 20th century. This can readily be traced to many factors, including societal changes in diet and smoking habits and advances in medical care. In particular, these factors include the Surgeon General’s reports on smoking and environmental smoke, as well as the advent of statins.

In Figure 3a, we present the death rate due to total CVD from 1900 to 2010.

Figure 3a Cardiovascular disease in the 20th Century, adapted from National Heart, Lung and Blood Institute statistics
Figure 3a
Cardiovascular disease in the 20th Century, adapted from National Heart, Lung and Blood Institute statistics

Again, we could ask how this curve might have looked if those societal advances had not occurred, and we represent one such alternate reality in Figure 3b. Figure 3b supposes that the identification of CVD risk factors and the Surgeon Generals’ reports on smoking and secondhand smoke did not happen.

What would have been the consequences? According to our calculations, this would have resulted in 19,948,307 excess deaths between 1960 and 2010.

Figure 3b Cardiovascular disease in an alternate 20th Century; adapted from National Heart, Lung and Blood Institute statistics
Figure 3b
Cardiovascular disease in an alternate 20th Century; adapted from National Heart, Lung and Blood Institute statistics

Motor vehicle safety is another of the great public health achievements of the last century and one of my favorite examples of structural change being associated with improved health. The core drivers of improved motor vehicle safety were federal regulatory efforts that improved the safety of vehicles and roads, changes in driving behavior and enforcement of driving laws, and public health communication efforts. Figure 4a shows the steep downward progression of the rate of death per million vehicle miles travelled over the 20th century.

fig7
Figure 4a
Motor vehicle death rate in an alternate 20th Century; adapted from figure 1 in Centers for Disease Control and Prevention (1999). Achievements in public health, 1900-1999: Motor vehicle safety. MMWR, 48(18)

Figure 4b shows one alternate version of reality, providing one potential answer to the following question: What if regulation of motor vehicle safety and enforcement of motor vehicle laws was never instituted? Taking the difference between the two curves, we estimate that this would have meant an excess of 1,218,915 deaths in the United States between 1967 and 1999.

Figure 4b Motor vehicle death rate in an alternate 20th Century; adapted from figure 1 in Centers for Disease Control and Prevention (1999). Achievements in public health, 1900-1999: Motor vehicle safety. MMWR, 48(18)
Figure 4b
Motor vehicle death rate in an alternate 20th Century; adapted from figure 1 in Centers for Disease Control and Prevention (1999). Achievements in public health, 1900-1999: Motor vehicle safety. MMWR, 48(18)

Hence, we can well ask in dark moments, whither public health?

But a fresh look at the achievements of public health suggests that if key public health interventions did not happen or were delayed, we would see 48,834,243 excess deaths from four major causes of death, in the United States between 1901 and 2032.

Undoubtedly one could apply this exercise to many other triumphs of public health, including the extraordinary improvement in global health over the past 25 years. Here I simply wanted to highlight simply some key domestic examples to suggest quantitatively that a world without public health, even without public health action on only a few key efforts, would have been a world with far fewer people indeed.

I hope everyone has a terrific week. Until next week.

Warm regards,

Sandro

Sandro Galea, MD, DrPH
Dean and Professor, Boston University School of Public Health
Twitter: @sandrogalea

PS: For anyone who is interested in the math, to derive the above estimates we extended best-fit line beyond the date of the key public health action that we “deleted,” and then calculated the new area under the curve to obtain excess mortality:

1st-equation

The equation for motor vehicle related deaths is the same, with the exception that
1st-label is substituted for 2nd-label.

In the case of cigarette smoking, assuming that consumption of 3 million cigarettes is associated with one lung cancer death and 90 percent of lung cancer in the United States is caused by tobacco, we obtained an estimate of excess tobacco-related lung cancer deaths associated with cigarettes consumed between 1968 and 1997 using the following formula:

2nd-equation

Acknowledgement: I am most grateful for the contributions of Gregory Cohen, MSW, to this Dean’s Note.

Explore Related Topics:

  • Share this story

Share

A World without Public Health

Comments & Discussion

Boston University moderates comments to facilitate an informed, substantive, civil conversation. Abusive, profane, self-promotional, misleading, incoherent or off-topic comments will be rejected. Moderators are staffed during regular business hours (EST) and can only accept comments written in English. Statistics or facts must include a citation or a link to the citation.

There are 4 comments on A World without Public Health

  1. I hope you had a good and restful Intersession!

    With regard to motor vehicle accident mortality, were you aware that many, many years ago I had published a study on motor vehicle accident mortality related to State motor vehicle inspection, namely, comparing those states (such as MA) that had annual motor vehicle inspection with those that did not? I will send you a copy of the paper (or bring one with me when we meet on Tuesday).
    Also, Ralph Hingson (former Chair of Behavioral Science) and Tim Heeren have done pioneeering work at BUSPH on mortality from motor vehicle accidents related to drunk driving, seat belt usage and other factors.
    Also, as I recall, the denominator of million-miles-driven is somewhat tricky. Over time, and with the changes in the power of motor vehicles and the evolution of super highways, the risks involved in driving one million miles are far different now than they were, say, 40 years ago when BUSPH was founded. I think it is exceedingly difficult to find an appropriate denominator for the examination of trends over time in risk of motor vehicle accident mortality.
    I look forward to seeing you on Tuesday!

    Link

    1. Ted: These are excellent points, thanks for raising them. I agree about the denominator issue. I look forward to seeing the paper you mention and to catching up later this week. Happy new year.
      Warmly
      Sandro

      Link

  2. A very interesting exercise, which prompts me to make a few observations. Please forgive what has turned into a rather lengthy treatise, but perhaps that is to be expected given the last 20 years I have spent participating in and observing the tobacco control movement.

    As a more general observation, I think it’s helpful to put the estimate of lives saved in the context of the total actual number of deaths in the U.S. that have occurred or will occur between 1901-2032. Using some rough calculations, I came up with a total of 226,565,000 deaths. If the estimate of almost 49 million lives saved is roughly accurate, that works out to about a 17.5% reduction in the overall number of deaths from the efforts described in this piece. Of course, since all those people did or will die anyway, it is probably more appropriate to think of the concept as lowering the death rate or extending life-years. Perhaps the next step would be to consider these measures, if anyone were interested in taking this exercise further.

    On to tobacco:
    First, while lung cancer is often used as the disease to track the effect of changes in tobacco use (because the population attributable fraction due to smoking is about 85%), it is of course only one of the many causes of death due to smoking. Smoking plays an important role in four of the top five causes of death in the US: cancer of many sites, heart disease, chronic respiratory disease, and stroke. Lung cancer alone accounts for about 30% of all smoking-related deaths. Thus, we could also ascribe about 2.5 million additional lives saved by tobacco control efforts (ignoring the double-counting of cardiovascular disease for the moment). An additional 50,000 deaths per year are estimated to be caused by exposure to secondhand smoke.

    Second, selecting a very few specific events as the drivers of decrease in tobacco consumption necessarily requires an over-simplification of a complex decades-long process, a point with which I’m sure the authors of the analysis would agree. And even events that may serve as inflection points have antecedents. Just to cite one example of the latter, the Fairness Doctrine (passed by Congress, required equal time for anti-smoking public service announcements in response to tobacco company ads on television, and quickly led to the end of cigarette advertising on that medium) would not have happened without the issuance of the Surgeon General’s report tying smoking to lung cancer (among men only!), which itself would have not come about in the absence of the studies in the 1950s that made the link, and the battle, fought out in a range of venues from scientific papers to the pages of Reader’s Digest, to establish that smoking was indeed a cause of lung cancer even though it didn’t fit the infectious disease paradigm.

    I would also argue that the Master Settlement Agreement between the tobacco companies and the state attorneys-general may have occurred coincident with an inflection point but was not itself a driver. Contrary to the original intentions, little of the settlement was actually spent by states on tobacco control. In fact, the MSA is better thought of as a marker of other drivers. Prominent among those I would identify the non-smokers’ rights movement, the legal strategy against the tobacco companies that led to the surfacing of damning documents that exposed the tobacco companies’ efforts at manipulation and obfuscation, and—perhaps most critically—the public’s acceptance of the studies that linked secondhand smoke (SHS) to lung cancer. This last development shifted the broader public’s perspective from viewing smoking as a perhaps regrettable but personal lifestyle choice to one of seeing it as a danger to the 75% of the population that didn’t smoke. The acceptance of this link was itself eased by the fact that smoking rates had declined (increasing the number of people in the category of those affected by SHS rather than producing it) and that the groundwork had been prepared due to earlier anti-smoking efforts. The result was a culture shift that began to view smoking as a non-normative behavior and an explosion of restrictions on smoking in an increasing number of venues. In a counterfactual world in which none of these public health measures were implemented, the excess toll of premature deaths would have been even greater than estimated under the assumption that the smoking rate would have declined but at a slower rate.

    While certainly a triumph of public health, it’s important to recognize that as smoking declined, the main beneficiaries were those with higher income and educational attainment. As smoking became more concentrated among the poor and those with less educational attainment, it became politically easier to impose restrictions because those higher on the ladder were not impacted. There was also a tendency to blame the smoker rather than recognize the condition as an addiction that required treatment (e.g., compare the lack of sympathy for victims of lung cancer compared to some other cancers). This gap has only continued to increase. Today, fewer than 10% of persons with a college degree smoke compared to approximately 30% of those with less than a high school education, a percentage that has not decreased for more than 20 years. A higher smoking rate also translates to much greater exposure to SHS for both adults and children–how many people at BUSPH any longer have any significant exposure to SHS? As a result, those in a lower socioeconomic position bear a highly disproportionate burden of diseases from smoking. It does lead one to wonder how history may have been different if the roles had been reversed. The social stratification of smoking is now playing out on a global scale, as 80% of all cigarettes are now consumed among low- and middle-income countries.

    As the first (?) major public health effort to reduce a non-communicable disease resulting from a widespread exposure, the anti-smoking effort is a source of many lessons both in the similarities and differences in strategies compared with other exposures and what to emulate and what to do differently.

    Link

  3. Thank you to Professor Brooks for these points. I agree with all of them. Here are the four points that emerge for me from Professor Brooks’ thoughtful comment.

    1. The consequences of public health action are compounded over time, suggesting that our estimate of the consequences of public health inaction are conservative. It is likely that one action not having been taken predisposes to another action also not being taken, with compound influence on the health of populations. This is of course foundational to the life course approach about which I have previously commented.

    2. We did not mention health equity in this Dean’s Note and the point is well taken that widening health gaps is as much a consequence of public health inaction as is the overall increase in preventable deaths. Further analysis could elucidate the implications of these inactions for health inequities.

    3. The methods we use here are limited by the counterfactual assumptions that underlie these approaches. It is hard to imagine a world where all else is the same except for inaction on one particular public health dimension. It is a limitation worth formally acknowledging, even if our capacity to address is limited.

    4. I agree with Professor Brooks that there is much that can be learned from tobacco. I wrote about this a little when I commented on social movements. One way one could have conducted this exercise is not to say ‘what would have happened had there been public health inaction’, but rather ‘what would have happened had we had earlier/better public health action’. That can be a rallying cry indeed, informed by cases (such as tobacco) where a social consensus emerged that prevented an extraordinary number of deaths.

    Link

Comments are closed.