Evolution of the global smoking epidemic over the
past half century: strengthening the evidence base forpolicy action
Xiaochen Dai ﻿﻿‍ ‍ ,1,2 Emmanuela Gakidou,1,2 Alan D Lopez ﻿﻿‍ ‍ 1,2► Additional supplemental
material is published online
only. To view, please visit thejournal online (http://​dx.​doi.​
org/​10.​1136/​tobaccocontrol-​2021-​056535).
1

Department of Health Metrics
Sciences, School of Medicine,
University of Washington,
Seattle, Washington, USA
2
Institute for Health Metrics
and Evaluation, Universityof Washington, Seattle,
Washington, USA
Correspondence to
Dr Alan D Lopez, Department
of Health Metrics Sciences,
University of Washington,
Seattle, WA 98195, USA. Dr.
Lopez was affiliated with IHME
and HMS when this work wasundertaken;​adlopez704@​gmail.c​ om
Received 9 October 2021
Accepted 4 January 2022

© Author(s) (or theiremployer(s)) 2022. Nocommercial re-­use. See rights
and permissions. Publishedby BMJ.
To cite: Dai X, Gakidou E,
Lopez AD. Tob Control
2022;31:129–137.

ABSTRACT
Background Despite compelling evidence on the healthhazards of tobacco products accumulated over the past
70 years, smoking remains a leading cause of deathworldwide. Policy action to control smoking requires timely,
comprehensive, and comparable evidence on smoking levels
within and across countries. This study provides a recent
assessment of that evidence based on the methods used in
the Global Burden of Disease (GBD) Study.
Methods We estimated annual prevalence of, andmortality attributable to smoking any form of tobacco from1970 to 2020 and 1990–2020, respectively, using themethods and data sources (including 3431 surveys andstudies) from the GBD collaboration. We modelled annual
prevalence of current and former smoking, distributions ofcigarette-­equivalents per smoker per day, pack-­years for
current smoking, years since cessation for former smokers
and estimated population-­attributable fractions due tosmoking.
Results Globally, adult smoking prevalence in 2020 was
32.6% (32.2% to 33.1%) and 6.5% (6.3% to 6.7%)
among men and women, respectively. 1.18 (0.94 to1.47) billion people regularly smoke tobacco, causing 7.0(2.0 to 11.2) million deaths in 2020. Smoking prevalence has
declined by 27.2% (26.0% to 28.3%) for men since 1990,
and by 37.9% (35.3% to 40.1%) for women. Declines
have been largest in the higher sociodemographic countries,
falling by more than 40% in some high-­income countries,
and also in several Latin American countries, notably Brazil,
where prevalence has fallen by 70% since 1990. Smoking
prevalence for women has declined substantially in somecountries, including Nepal, the Netherlands and Denmark,and remains low throughout Asia and Africa. Conversely,
there has been little decline in smoking in most low- andmiddle-­income countries (LMICs) with over half of all men
continuing to smoke in large populations in Asia (China,
Indonesia), as well as the Pacific Islands.
Implications While global smoking prevalence has fallen,smoking is still common and causes a significant healthburden worldwide. The unequal pace of declines acrossthe globe is shifting the epidemic progressively to LMICs.
Smoking is likely to remain a leading cause of preventable
death throughout this century unless smoking cessation
efforts can significantly and rapidly reduce the number ofsmokers, particularly in Asia.
Funding XD and EG received funding through grant
projects from Bloomberg Philanthropies (funding no. 66-­9468) and the Bill & Melinda Gates Foundation (funding no.
63-­3452).
INTRODUCTION

Shortly after epidemiological research during the1950s established cigarette smoking as a major causeof death, particularly in countries where smoking
had become widespread, public health agencies incountries such as the UK and the USA issued majorreports documenting the health hazards of smoking.1 2
Although the hazards were first widely documented
more than 50 years ago, smoked tobacco products,
including manufactured and hand-­rolled cigarettes,
pipes, cigars, waterpipe, bidis, kreteks and other local
smoked tobacco products, remain common in many
countries. This has been accompanied by substantial
death and disability directly attributable to tobacco
products, to the point where smoking is the leading
cause of disease burden in many countries.3–7 Beginning with the seminal work of Doll and Hill8 in the UK
and Hammond and Horn9 in the USA, which provided
early, compelling evidence on how persistent smoking
affects health and survival, numerous studies havedescribed the individual mortality risks from smoking
and how these have evolved.10–15 Others quantify the
impact of smoking on national, regional and global
mortality levels.16–18 The sheer volume of death anddisability attributable to tobacco underscores theimportance of tobacco control as an urgent global
health priority. Based on recent trends in smoking
uptake among young people, and assuming that the
addiction will eventually kill half of all smokers,
cigarette smoking is estimated to have caused over
100 million deaths last century and will cause over1 billion deaths this century unless more effective
measures are taken to end the tobacco epidemic.19
Policy action to control smoking has been
complicated, and occasionally confused, by thepowerful temporal and political characteristics ofthe epidemic, with a long lead time between populations taking up smoking and subsequently experiencing the full disease effects, and a powerfulindustry opposing effective public health measures.
Nearly three decades ago, Lopez et al proposed aseries of stages of the tobacco epidemic over thecourse of the 20th century that showed how prevalence and mortality had evolved for men, and then,
two to three decades later, for women as well.20
This temporal characterisation of the epidemic,
and a subsequent update almost two decades
later that incorporated emerging evidence fromlow- and middle-­income countries,21 has served tobetter inform and stimulate policy action to reducesmoking prevalence, disease and deaths.22
Smoking control efforts ought to be guided bya more granular description of how smoking prevalence and consumption have evolved. Country-­
specific evidence on changes in smoking levels andpatterns according to age, sex, geography and socioeconomic status is critical to stimulate and monitor

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the effectiveness of policies to reduce population exposure totobacco hazards. Where, for example, is smoking prevalence forwomen increasing, or decreasing, at a faster rate than for men?
Are smoking rates rising among adolescents while falling among
adults? Are trends in smoking rates similar across socioeconomic
groups? Have there been important changes in consumption
patterns, with more (or fewer) daily smokers than was the caseearlier? Reliable and timely information on key aspects of thetobacco transition will provide countries with critical intelligence for policy, including the effectiveness of past tobacco
control efforts and how they might need to be modified, particularly to target population subgroups with the greatest needs.
This study provides a comprehensive and comparable assessment of how the global smoking epidemic has evolved overthe past 50 years, characterising more than 200 countries andterritories according to their epidemic phase, and detailing how
smoking prevalence and its attributable burden has changed formen and women at different ages, and, importantly, for populations at different levels of development.

METHODS
Overview

The Global Burden of Disease, Injuries and Risk Factors (GBD)
Study is a systematic analysis of 369 diseases, injuries, and 87 risk
factors in 204 countries and territories.3 23 As part of the GBD
2020, we estimated the prevalence of and the health burden(deaths and disability-­adjusted life years, ie, DALYs) attributableto smoked tobacco use from 1970 to 2020 and from 1990 to
2020, respectively, for 204 countries and territories by 5-­year
age group and sex. Secondhand smoke exposure, smokelesstobacco (e.g., snus), electronic cigarettes, vaping products andheated tobacco products also contribute to the overall disease
burden but were excluded from this analysis. Henceforth, we
use the term ‘smoking’ to refer to ‘smoked tobacco use’ of one
or more of the products mentioned earlier.
We used a direct estimation method for 36 health outcomescaused by smoking that have a dose–response relationship withboth current and former smoking. Full details of the estimation method are described elsewhere.3 4 We summarise the keymodelling steps: estimating prevalence of current and former
smoking; modelling distributions of smoking exposure including
cigarette-­equivalents of tobacco smoked per day, pack-­years for
current smoking and years since cessation for former smoking;calculating population-­
attributable fractions (PAFs) using theclassic attributable risk formula based on prevalence estimatesand relative risks from an appropriate source.24

Prevalence of smoked tobacco use

To estimate prevalence of current and former smoking, we
performed a systematic review of the literature and extracted dataon key smoking indicators, only including surveys that were nationally or subnationally representative (state/province level). Surveys
conducted among specific populations (e.g., pregnant women,
physicians) were excluded. A total of 2808 surveys, covering 200
of 204 countries and territories were included in this analysis. We
extracted individual-­level microdata or report tabulations from thesurveys for people aged 10 years and above. We excluded estimateswith sample size less than 10 to avoid unstable estimates. Following
data extraction, systematic data quality checks were performed to
identify and exclude implausible or inconsistent data. A complete
list of data sources used in this study can be found in the online
supplemental materials and data are available in Global Health Data
Exchange (http://ghdx.healthdata.org/). More detailed information130

on the search strategy, inclusion criteria and data extraction methods
can be found elsewhere.4
To ensure data comparability and to avoid compositional bias, we
mapped all non-­reference case definitions to our reference case definitions. We then applied spatiotemporal Gaussian process regression (ST-­GPR) to model prevalence for both current and former
smoking.3 23 We produced 1000 draws from the posterior distribution of ST-­GPR and used the 25th and the 975th draws to constructuncertainty intervals around the final estimates. Details of thesemethods and ST-­GPR are published elsewhere.25 26

Exposure distribution

To estimate deaths and DALYs attributable to smoking, we firstestimated the distributions of intensity of smoking and numberof years since cessation among current and former smokers,
respectively. To capture smoking intensity, we estimated distributions of both cross-­sectional cigarette-­equivalents of tobacco
per smoker per day and lifetime cumulative pack-­years. We estimated the cigarette-­equivalents consumed per smoker per day
using two data sources, namely, self-­reported consumption datafrom household surveys and supply side country-­level tobacco
consumption data from the Euromonitor (2002–2017), the US
Department of Agriculture (1960–2005), and the Food and Agriculture Organization of the UN (1961–2013). To estimate distributions of pack-­years, we simulated individual smoking history
using distributions of cigarette-­equivalents per smoker per day
and age of smoking initiation. For the distribution of years since
cessation, we simulated cessation behaviour of current smokers
using survey data on age of cessation by sex, age group, country
and year. Full details of how we modelled exposure distributions(i.e., tobacco use) have been published elsewhere.4

Dose–response risk curves

We used a new meta-­
regression method27 to re-­estimate thedose–response risks of current smoking for 36 health outcomescaused by smoking, based on an updated systematic review
of literature.3 4 We included 623 studies that report risk ofsmoking on the outcomes among both the overall populationand subpopulations (e.g., nurses or workers) but removed those
conducted among people with certain pre-­existing conditions(e.g., diabetes). For former smokers, we modelled risk-­reduction
curves for years since cessation and standardised the risk at
the time of cessation using the exposure-­weighted risk integral
for current smokers in each age, sex, location and year group.
Bayesian methods provide uncertainty of estimates based on
small sample size to avoid unstable estimates. Full details of themethods can be found elsewhere.28 Data sources used in thisanalysis can be found in online supplemental materials.

Population-attributable fractions

The detailed formula used to calculate PAFs is described elsewhere.4 To account for the delayed effect of smoking on healthoutcomes, we lagged the exposure based on the average lengthof follow-­up across the studies included in the meta-­regression.
We calculated deaths and disease burden (DALYs) attributableto smoking by applying the PAFs to cause-­specific deaths and
DALYs by year, location, age group and sex. All analyses were
performed using R (V.3.6–4.1) and Python (V.3.3).

Sociodemographic Index

Estimates are also provided by quintile of Sociodemographic
Index (SDI), a composite measure of educational attainment,
income per capita and total fertility rate under age 25 years.29
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Original researchSince the SDI for a country can change over time, we groupedcountries based on their SDI in 2020.

Guidelines for Accurate and Transparent Health Estimates
Reporting complianceThis study complies with the Guidelines for Accurate and Transparent Health Estimates Reporting recommendations.30 Resultspresented in this manuscript are publicly available: https://
vizhubhealthdataorg/gbd-compare/.

RESULTSTo assess the evolution of the global smoking epidemic over the
past half century, we estimated the fraction of the adult population who are smokers (prevalence) and the amount they smoke(consumption). Both metrics are relevant to inform and monitor
tobacco control measures. Figure 1 shows prevalence levels, forwomen and men separately, in 1970 and again in 2020 (prevalence levels in 2000, by sex, are shown in online supplemental
figure S1). For men, prevalence levels exceeded 40% in muchof the world except sub-­Saharan Africa, and were between 30%
and 39% in India, as well as the USA, UK, Australia and New
Zealand, where prevalence was as high as 60%–70% in the late
1940s.11 By 2000, male prevalence had already declined substantially in many countries, but remained high in Eastern Europe,
Southeast Asia, China, Spain (among Western Europe) and partsof Latin America. Prevalence fell further by 2020, particularly
in Latin America and India, with levels below 30%. For women,prevalence levels above 30% 50 years ago were only evident inseveralOECD (the Organisation for Economic Co-­
operation
and Development) countries including Canada, the USA, theUK, Australia and New Zealand—as well as many countries inWestern Europe, notably Denmark and the Netherlands, wherefemale smoking rates exceeded 40%, and in the southern coneof Latin America. By 2000, smoking rates in the USA and several
other OECD countries fell below 30%, and fell below 20% by
2020, except for a handful of countries in Europe, including
Spain, France, Switzerland, Poland and Hungary. Female
smoking rates in Chile remained above 30%.
In 2020, more than half of all adult men in parts of the
Indo-­
Pacific region (Micronesia, Kiribati, Timor-­
Leste, Indonesia, Papua New Guinea, Solomon Islands) were smokers, as
was the case for Armenia, Mongolia, Jordan (54%–56%) andChina (52%). Female prevalence was highest (34%–40%) in
Pacific Island countries (Nauru, Micronesia, Kiribati), but lessthan 2%–3% for women in several countries in Africa, as well as
Tajikistan and Sri Lanka (see figure 1).
Figure 2 summarises the magnitude of change in trends insmoking prevalence over the past 20 years. For men, prevalence
has declined by more than 10 percentage points in a number ofcountries since 2000 including Canada, Russia, the UK, Australia,
Brazil and India; while in others, including China, much ofWestern Europe, the USA, Chile and Argentina, declines havebeen more modest. Parts of North Africa (Egypt, Libya, Iran)and East Asia have seen some increase in male prevalence since
2000, as has Botswana. On the other hand, female prevalence
has not changed significantly since 2000 in most countries, ordeclined by less than 10 percentage points. Notable exceptions
are Nepal, Brazil, Norway, Denmark, the Netherlands, New
Zealand and the UK, where smoking levels among women havefallen by more than 10 percentage points.
Several countries have succeeded in reducing smoking
rates over the past two decades, with the largest declines
in age-­standardised prevalence for men being observed inJapan (down 18.8 percentage points, 95% CI: 16.5 to 21.1),
Dai X, et al. Tob Control 2022;31:129–137. doi:10.1136/tobaccocontrol-2021-056535

Ukraine (17.7 percentage points, 95% CI: 15.6 to 19.9), Nepal(17.5 percentage points, 95% CI: 15.3 to 19.8) and Brazil(17.5 percentage points, 95% CI: 16.0 to 19.1), as well as in
Norway, Turkmenistan, Paraguay, Colombia and Denmark,all recording falls of around 15 percentage points since
2000. The largest declines in smoking prevalence for women(13–17 percentage points) occurred in Nepal, Norway, Denmarkand Brazil, with reductions of 10 percentage points or so also
observed in New Zealand, the UK, the Netherlands and Canada.
A key indicator of future smoking prevalence is the level ofsmoking among youth and adolescents, and especially whether
those levels are rising. Online supplemental figure S2 shows
trends in prevalence among youth since 2000 according to themagnitude of change. In most high SDI countries, as well as in
Russia, Brazil and Mexico, youth smoking prevalence amongmen declined by more than 10 percentage points over the past
20 years. Otherwise, there has been no significant change insmoking among young men; and in some countries, including
Iran, Algeria, Jordan and Bolivia, prevalence has increased
significantly. Among women, youth smoking prevalence also
declined by more than 10 percentage points in the majority ofhigh SDI countries, but by less than 10 percentage points inJapan and Eastern and Central European countries. There has
been little change in youth smoking levels among women overthe past 20 years in most low- and middle SDI countries.
To assess how prevalence varies, and is evolving, across various
socioeconomic groups in the population, prevalence trends since1970 according to five SDI categories are shown in online supplemental figure S3. In 2020, male smoking prevalence was highest in
the high-­middle (second highest) SDI group, not the highest category, for whom reductions in prevalence are apparent since 1970.
In other SDI groups, smoking prevalence only began to decline 20
years later, around 1990, except for the low SDI group where littlechange in prevalence is discernible. Among women, smoking prevalence in the high SDI group has fallen by about 50% since 1970,
with little change evident for all other SDI categories.
Another way to assess the impact of smoking control policies
is to examine how smoking rates have varied for successive birthcohorts of men and women, as shown in online supplemental
figure S4. It illustrates a characteristic age-­related pattern, withsteep increases at younger adult ages until about age 30 years,
then declining prevalence with advancing age, with very littlechange in the age pattern over the past century. There has,
however, been a steady decline in prevalence, for both men andwomen, beginning with the birth cohort born around 1970. For
men, this trend is most apparent for the high-­middle and low-­
middle SDI countries. For women, the decline in prevalence ismost noticeable for the high SDI category, being about 50%
lower at age 20 years for the 2000 birth cohort than for womenborn a century earlier.
Changes in the consumption of smoked tobacco over the past
50 years can be seen from online supplemental figure S5a fordifferent SDI groups. As noted for prevalence, male consumption is highest in the high-­middle SDI group, being about twice
as high as for other SDI categories. Consumption increased inthis group of countries between 1970 and 1995, although it has
declined since then. By far the largest declines in consumption
have occurred in the high SDI group, falling by about 50%,
compared with 25%–30% in other SDI groups. Female consumption is highest in the high SDI group, being about twice the levelin other SDI categories, although consumption levels have fallen
by about 60% since 1970. Reductions in female consumption in
the middle SDI group have been almost as large (50%), but lessso in the high-­middle SDI category.
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Figure 1 Age-­standardised prevalence of current smoking for males and females aged 15 years and above, in 1970 and 2020. 1The standard population age weights used for calculating age-­standardisedprevalence are taken from the Global Burden of Disease study.23

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Figure 2 Absolute percentage points change of age-­standardised prevalence of current smoking for men and women aged 15 years and above from 2000 to 2020. 1The percentage points change inprevalence between 2020 and 2000 is grouped into five categories according to the magnitude of the change and the statistical significance of the change. 2The standard population age weights used for
calculating age-­standardised prevalence are taken from the Global Burden of Disease study.23
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There has been little change over the past few decades in thenumber of cigarette-­equivalents smoked per smoker per day,except for the high SDI category—although this decline appears
to have stalled during the past 5 years—and the modest but
steady increase in consumption in the high-­middle SDI group(see online supplemental figure S5a).
Trends in consumption over the past half century in different
geographical regions (as defined by the GBD Study) are shown inonline supplemental figure S5b. In 2020, consumption among men
was highest in Southeast and East Asia, rising sharply between 1970
and 1990, followed by modest declines. The next highest consumption levels for men are in Central and Eastern Europe, although
there too some reduction in consumption has occurred since 2000.
Consumption of tobacco by male smokers is lowest in sub-­SaharanAfrica and Latin America. In the latter region, consumption has
declined by about two-­thirds since 1970. The other country groups
experiencing big declines in consumption among men are the high-­
income countries, where levels have fallen by about 60% since 1970.
Similar reductions in consumption are also apparent for women in
high-­income countries, and in Latin America, but with little change
in other regions.
There has been little change in the fraction of smokers who
smoke daily versus less than daily (see online supplemental table1). While there is some variation in the relative fraction of daily
smokers across SDI groups, region and by sex, these proportions
have remained relatively constant since 2000. The most noticeable change was an increase in the fraction of former smokers,
most of whom were former daily smokers.
With concern for how trends in smoking prevalence andconsumption affect the burden of disease in countries. Figure 3
shows how the fraction of deaths at ages 30 years and over that are
attributable to smoking has changed over the past three decades,
separately for men and women. In 1990, more than 20% of maledeaths above age 30 years in several countries including the USA,
Canada, much of Europe, Australia, New Zealand, Japan, Southern
Latin America, China, Malaysia and the Philippines were attributable to smoking. Smoking-­attributable mortality was 15%–19%in Brazil, South Africa, India and Indonesia. By 2020, the fractionof deaths due to smoking had declined to 15%–19% in the USA,
Canada, the UK and most of Western Europe, and even lower,
to 10%–14%, in Sweden, Norway, Finland, Australia and New
Zealand. Smoking-­attributable mortality was still high (exceeding
one in five deaths) in Eastern and Central Europe, Spain, Egypt,
the Philippines, China and Indonesia, but had fallen to less than 1
in 10 deaths in Mexico and tropical Latin America, and remained
low in sub-­Saharan Africa.
Among women, more than one in five deaths above age
30 years in 1990 were attributable to smoking in the UK and
Denmark, reflecting their early, and substantial, female smoking
epidemics. Smoking also claimed 15%–20% of deaths among
women at these ages in the USA, Canada and Ireland, and
10%–15% in Australia, where the impact of smoking control
measures was already apparent. By 2020, less than 10% of
female deaths in Australia were attributable to smoking. In
Chile, smoking-­attributable mortality is rising following widespread increases in female prevalence (see figure 1). Typically,smoking currently causes 10%–14% of female deaths in theUSA, Canada and Europe, but remains low as a cause of death—less than 5%—throughout Asia and Africa.
Based on changes in prevalence of smoking, we classified the204 countries or territories according to their (current) phase of
the tobacco epidemic in figure 4, for men and women separately.
Table 1 summarises the prevalence levels and changes that characterise each of the four stages.
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Figure 3

Per cent of deaths attributable to smoking for men and for women aged 30 years and above, in 1990 and 2020.

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Figure 4 Classification of countries according to stages of the tobacco epidemic in 2020, by sex. 1For men, the definitions of four phases are (1) current prevalence <15%; (2) current prevalence now
15%–65% and never declined, or only declined by <10% points; (3) prevalence has declined by >10% points but is still >25%; (4) prevalence has declined by >10% points and is now <25%; for women,
the definitions of four phases are (1) current prevalence <5%; (2) current prevalence now 5%–45% and never declined, or only declined by <5% points; (3) prevalence has declined by >5% points but isstill >20%; (4) prevalence has declined by >5% points and is now <20%. 2The colour codes are based on the severity of the implications of smoking levels for policy, with red indicating the worst scenario,
orange the second-­worst scenario, yellow the neutral scenario and green the best scenario.
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Table 1 Operational definitions of four phases of the tobacco
epidemic (and number of countries), by sex
StagesFemaleMale

Incipient stage*

Current prevalence <5% (80)†Current prevalence <15% (17)Phase two

Current prevalence now 5%–
Current prevalence 15%–65% and
45% and never declined, or only never declined or declined by <10%declined by <5% points (64)points (85)Phase three

Prevalence has declined by >5% Prevalence has declined by >10%
points but is still >20% (27)points, but is still >25% (52)

Phase four

Prevalence has declined by >5% Prevalence has declined by >10%
points and is now <20% (33)points, and is now <25% (50)*Countries at this stage, by definition, have never experienced prevalence levels that wouldclassify them to any subsequent epidemic stage; some countries in stage 4 might have
similarly low prevalence levels following extensive declines.
†Numbers in parentheses are the number of countries classified into each phase.

Female prevalence data suggest that 40% of countries, halfof them in sub-­Saharan Africa, are still in the incipient stage ofthe epidemic, with very low prevalence. Large countries of Asia,
including India, China, Bangladesh and Indonesia, belong inthis phase. Another 31% (64 countries) have moved into phasetwo, with rising prevalence and little evidence of decline. One-­quarter of these are Pacific Island countries, another quarter
include Russia, and Central and Eastern European countries,
and 10 countries are in Latin America. Interestingly, France andPortugal, alone among high-­income countries, are at phase two,and six phase two countries are from sub-­Saharan Africa. Among
27 phase three countries, 17 are high-­income Western European
nations, as well as Argentina, Chile and Uruguay, and 8 countries
from Central/Eastern Europe. Only 33 countries (16% of total)have transitioned to phase four with comparatively low (<20%)
prevalence, including the USA, the UK, Australia, Canada, New
Zealand, Japan and all of Scandinavia, except Denmark. Italy, but
no other Southern European nation, transitioned to phase four.
Nine Latin American countries, including Mexico, Colombia,
Brazil and Cuba, have also transitioned, as well as three fromsub-­Saharan Africa (South Africa, Namibia, Sierra Leone).
The epidemic classification of countries according to male prevalence reflects the earlier and more pervasive smoking practicesof men compared with women. Only 17 (8%) countries still havemale prevalence levels sufficiently low (<15%) to classify them as
being in the initial phase. All are low or low-­middle SDI countries,
including 10 in sub-­Saharan Africa, and 6 Caribbean countries,
including Haiti and the Dominican Republic. Eighty-­
five (42%)
countries have moved to phase two, with broad representation
across all regions, indicating how pervasive the epidemic is. Thirteen Pacific Island countries or territories, 17 in sub-­Saharan Africa,
15 from Central/Eastern Europe, 10 from Latin America and 16
from the Middle East/North African region have been classified
phase two, as well as Indonesia and Timor-­Leste, with the highest
smoking rates in the world, and a handful of high-­income countries,
including Austria, Portugal, Cyprus and Chile.
Prevalence has started to decline in 52 countries (25%) classified into phase three, including 10 from Southeast Asia (including
China), and 5 in the Pacific, including Fiji and Tonga. Almostone-­third of countries (16) in this phase are high SDI nations ofWestern Europe, but also Japan, Argentina and Uruguay. Another12 are from Central/Eastern Europe, including Russia, Hungary
and Poland, and 2 (Mexico and Cuba) from Latin America.
One-­quarter of countries (50) have reduced male smoking
prevalence to below 25% (phase four), primarily the Anglo-­
Saxon nations, all of Scandinavia, including Denmark, as well as
Singapore, Belgium and the Netherlands, where smoking rates
had been among the highest in the world. This category contains
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Original research15 Latin American countries, including Brazil, Colombia andCosta Rica, 14 in sub-­Saharan Africa and 2 (India, Pakistan) in
Asia, suggesting that tobacco control measures have been appliedwith some success more globally. Overall, less than half of all
countries (93) or territories were similarly classified based onmale and female prevalence.

DISCUSSION

Globally, 1.18 (95% CI: 0.94 to 1.47) billion people in 2020
regularly smoked some form of tobacco, causing 7.0 (95% CI:
2.0 to 11.2) million deaths, or about one in seven of all deaths
that occurred that year.4 From smoking levels in excess of 40%
among men around 1970 in many high SDI countries, prevalence
has more than halved over the past 50 years and has declined
substantially in Latin America. Conversely, with few exceptions,
there has been little decline in smoking in most low- and middleSDI countries, with more than half the adult male population inlarge populations of Asia (China, Indonesia) and Pacific Island
countries smoking regularly. Smoking rates among women in the
more high SDI countries never attained the levels of men, typically lagging male smoking by two to three decades. Smoking
levels among women throughout Asia and Africa, with very few
exceptions, have remained low. Prevalence levels for successive
birth cohorts, particularly in high sociodemographic groups,
have consistently declined beginning with those born around1970. Prevalence has also declined among other sociodemographic categories, less so in the high-­middle sociodemographic
group. In terms of established models of the tobacco epidemiological transition, these data for men suggest that less than 10%of countries are at the incipient stage, 42% in stage two whereprevalence is rising or has peaked and not yet declined, 25%
in stage three where prevalence is declining, but still high, andanother quarter where declines have pushed prevalence to below
25%. For women, the respective per cent distribution of countries across the phases is 40/31/13/16.
These divergent trends in prevalence across countries, sociodemographic groups and by age and sex, as well as the differential classification of countries according to phase of theepidemic, provide a number of important lessons for national,
regional and global tobacco control policies. Most importantly,
they strongly suggest that tobacco control measures, particularly when implemented comprehensively, work, collectively
leading to a 27.2% (95% CI: 26.0% to 28.3%) global decline insmoking prevalence among men since 1990, and a much larger
decline, 37.9% (95% CI: 35.3% to 40.1%) among women.31 32
The substantial declines observed among the higher sociodemographic group demonstrate their effectiveness among populations having greater access to health resources and choices thatenhance health consciousness, responsiveness to health messages
and avoidance of health risks than other sectors of the population. This is much less evident among the next sociodemographic
category (high-­middle), although this may well reflect compositional issues since the experience of China would dominate thiscategory, at least in more recent years.
The phasing of the tobacco epidemic in countries that we havedescribed here includes some important reminders for global
tobacco control efforts. First, the large number of countries wherefemale smoking levels are very low could well follow the transition
observed for men unless important lessons are learnt, and applied,
about smoking disincentives for women. Second, the factors thatmove countries from phase two (rising or stable prevalence) tophase three (modest declines) need to be better understood if thisphase of the transition is to accelerate. Third, what has been therole of sociocultural context, including civil society, in moving
136

countries into phase four? This transition has been especially prominent for the Anglo-­Saxon and Scandinavian countries, along with
Singapore, but, importantly, in several Latin American countries
as well, including Brazil, Mexico, Colombia and Costa Rica. The
reductions in prevalence observed in Brazil have been attributed
to important regulatory measures implemented by the country
over the past few decades, and, especially after the ratification of
the WHO Framework Convention on Tobacco Control(FCTC) in
2005.31 These measures included a national ban on tobacco advertising, a national comprehensive smoke-­free policy, large pictorial
health warnings on cigarette packages, and continuous raises intaxes and prices of tobacco products. Recent years have shown aplateauing in the decreasing trend, however. In order to continue
to make progress and lower smoking rates even further, a plan formonitoring tobacco use, a list of actions for tobacco control andnational tobacco use reduction goals were added to the country’s‘Strategic Action Plan for Coping with Noncommunicable Diseases,
2011–2022’.33 34 Other countries in the region have also implemented tobacco control strategies over the past couple of decades,though the level of compliance and enforcement has varied within
and across countries. Important lessons can be learnt on successfully
reducing prevalence of smoking by understanding the drivers ofchange in Brazil, and other countries in the region.
Our findings should be interpreted taking into consideration
the study’s limitations, primarily related to data quality and availability. Despite rigorous attempts to ensure our estimates are basedon comparable and consistent data, data gaps and inconsistencies
lead to substantial uncertainty in the trends and patterns of smoking
prevalence and consumption in some countries, reducing the policy
utility of the estimates. In this study, we used the direct method toestimate PAFs. Note that PAFs have also been estimated using anindirect approach, with the level of lung cancer mortality being
used as a measure of the ‘maturity’ of the epidemic in populations,with relative risks from some reference study being scaled accordingly.7 16 The GBD Study previously used the indirect method26 but
switched to the direct method a few years ago. We did not find thetotal burden due to smoking changed significantly using different
methods. Given the significant role of recent, reliable and comprehensive information on the smoking epidemic for guiding and evaluating policy responses in countries, much more could be doneto assist countries to improve their epidemiological surveillance
capacity and systems, especially for smoking prevalence, consumption and mortality data.
Timely, detailed, reliable and comparable estimates of tobacco
use and its harms provide the essential health intelligence forcountries and the global tobacco control community alike on
which to determine policy imperatives, identifying populations where smoking control measures have been particularly
successful, as well as populations where urgent policy action
is required to reduce future disease burden. Predictions of 1
billion deaths from smoking this century unless there is urgent
and substantial progress with cessation strategies19 highlight theenormous toll of avoidable mortality that smoking will cause, in
the absence of effective national policy responses, especially inhigh prevalence countries. Protection and promotion of publichealth requires that countries not only respond urgently tocontrolling global pandemics, such as COVID-­19, but equally
urgently and simultaneously act more decisively against large,
preventable and systemic causes of premature death and healthloss, particularly smoking.
Contributors XD had full access to, verified all the data in the study, and takes
responsibility for the integrity of the data and the accuracy of the data analysis.
ADL controlled the decision to publish and takes full responsibility for the work.
Dai X, et al. Tob Control 2022;31:129–137. doi:10.1136/tobaccocontrol-2021-056535

Tob Control: first published as 10.1136/tobaccocontrol-2021-056535 on 3 March 2022. Downloaded from http://tobaccocontrol.bmj.com/ on September 15, 2024 by guest. Protected bycopyright.

Original researchWhat this paper adds
► We provide a 50-­year evolution of the smoking epidemic

worldwide according to broad phases characterised byprevalence trends among men and women, as well as byage, sex, country, region, Sociodemographic Index and birthcohorts; these are the key descriptors needed to inform
global, regional and national policy action.
► We show how mortality attributable to smoking has evolved
between 1990 and 2020, by country and separately for men
and women, providing the most recent global assessment of
the health consequences of smoking and how it has changed.
► Using rigorous data-­adjustment methods, we provide
comparable measures of prevalence and consumption overtime and across countries, facilitating assessments of where
policies have worked and where they are most needed.
Conceptualisation—all authors. Data curation— XD. Supervision—EG and
ADL. Methodology—all authors. Statistical analysis and programming—XD.
Visualisation—XD. Writing (first draft)—XD and ADL. Writing (review and editing)—
all authors.
Funding XD and EG received funding through grant projects from Bloomberg
Philanthropies and the Bill & Melinda Gates Foundation.
Disclaimer The funders of the study had no role in study design, data collection,
data analysis, data interpretation or writing of the report.
Map disclaimer The inclusion of any map (including the depiction of any
boundaries therein), or of any geographic or locational reference, does not imply theexpression of any opinion whatsoever on the part of BMJ concerning the legal statusof any country, territory, jurisdiction or area or of its authorities. Any such expression
remains solely that of the relevant source and is not endorsed by BMJ. Maps areprovided without any warranty of any kind, either express or implied.
Competing interests None declared.
Patient consent for publication Not required.
Ethics approval This study was a secondary analysis based on publicly available
datasets. The included surveys and studies were all approved by the Institutional
Review Boards and the respondents provided written informed consent. Ethicalapproval was not required for the analysis of those anonymised data.
Provenance and peer review Commissioned; externally peer reviewed.
Data availability statement Data are available upon reasonable request.
ORCID iDs
Xiaochen Dai http://orcid.org/0000-0002-0289-7814
Alan D Lopez http://orcid.org/0000-0001-5818-6512

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Original research