Depending on the observer's epidemiological perspective and concept of causality, tobacco consumption can be considered the second leading cause of death attributable to classic cardiovascular risk factors worldwide, exceeded only by hypertension, and the leading cause of premature death and disability. When taken as an immediate cause, without contextualization in the complex processes that determine and maintain population behavior, in 2017 smoking was responsible globally for about 7.10 (6.83-7.37) million deaths and 182 (173-193) million disability-adjusted life-years (DALYs). Although the number of daily smokers (individuals aged 15 years and older who smoke every day) has decreased, the total number of smokers continues to rise, posing a major global challenge for healthcare systems.1

Physicians, who generally deal directly with individual patients, tend to consider health and illness to be limited to the patient's organ compromise and personal history, and are less appreciative of the ‘causes of the causes’ and the psychosocial determinants of phenomena and behaviors, which are inseparable from the ecological context and from economic interests. Environmental pollution (which is also worsened by smoking) is progressively increasing and is currently considered to be the most important cause of morbidity and mortality in the world,2 extending beyond the traditionally accepted risk factors. This fact is important for an understanding of the resistance to smoking control and for planning effective strategies to deal with the issue.

In all Portuguese-speaking countries (PSCs), smoking is more prevalent among men. The difference in rates between men and women varies between countries and is greater in the African countries. Table 1 shows the standardized prevalence by gender in 2015 and the annualized changes for men and women from 1990 to 2015 according to the sociodemographic index (SDI), the weighted geometric mean of per capita income, level of schooling and total fertility rate.3 The proportion of daily smokers in the PSCs is 19.0%, 16.8%, and 7.2% in African countries, Portugal, and Brazil, respectively.4

Data from the Portuguese National Health Surveys (INS) (1987, 1995/96, 1998/99, 2005/06, and 2014) show that the prevalence of daily smokers in mainland Portugal decreased among men from 35.2% (95% confidence interval [CI] 34.2-36.2%) in 1987 to 26.7% (95% CI 25.2-28.3%) in 2014, and increased in women from 6.0% (95% CI 5.6-6.4%) in 1987 to 14.6% (95% CI 13.6-15.8%) in 2014, with a higher prevalence in men from more disadvantaged socioeconomic groups and the opposite in women.5

The reported prevalence of smoking in Mozambique in 2003 was 39.9% in men and 18.0% in women.6 In a 2005 sample from the same country, the prevalence of daily tobacco use (including users of chewing tobacco, snuff, manufactured cigarettes, and hand-rolled cigarettes) had fallen to 33.6% in men and 7.4% in women, with different prevalence rates by gender and regions of the country.7

Brazil is the leading country among the PSCs in the control of smoking, with the third largest decline in the prevalence of daily smokers since 1990: 57% and 56% for men and women, respectively. This was achieved through a robust public policy, in which advertisements highlighting the harm to health caused by smoking were associated with restrictions on consumption and tax increases on tobacco products, among other measures.8

These measures stemmed from adherence to the recommendations by the World Health Organization (WHO)’s Framework Convention on Tobacco Control (FCTC),9 which include banning of terms such as ultra-light, light, low tar, mild, or any other term implying that such products are less harmful. The PSCs have joined the FCTC at different times, as discussed below in the section on legislation.

The percentage of deaths attributed to tobacco use across 195 countries increased from 7.28 (7.01-7.56) million in 2007 to 8.10 (7.79-8.42) million in 2017, an increase of 11.3% (9.1-13.4%), according to the Global Burden of Disease study.1 The same was seen with DALYs, from 200000 (188000-212000) in 2007 to 213000 (201000-227000) in 2017, an increase of 6.8% (4.6-9.0%). A similar trend was observed with regard to ischemic heart disease, from 1.50 (1.44-1.57) million deaths in 2007 to 1.62 (1.54-1.69) million in 2017, a 7.8% increase (4.6-11.1%), while DALYs increased from 38.4 (36.8-40.2) in 2007 to 40.6 (38.7-42.5) million in 2017, an increase of 5.6% (2.4-9.0%). Similar increases were observed in relation to deaths due to ischemic stroke, from 295000 (276000-317000) in 2007 to 335000 (313000-361000) in 2017, an increase of 13.4% (8.6-17.8%), with an increase in DALYs from 7.54 (69.1-8.26) million in 2007 to 90.0 (81.7-99.2) million in 2017, an increase of 19.3% (14.7-23.8%).1

It is important to note that approximately 80% of smokers live in low- and middle-income countries,10 which includes most of the populations of the PSCs, where the decline in tobacco consumption seen in high-income countries has not been observed.4 There is strong evidence that treating smoking in primary care is both opportune and cost-effective because of the wide coverage and the close long-term relationship between physician and patient in primary healthcare.11

Of the traditional risk factors considered in clinical practice for prevention of cardiovascular disease (CVD), smoking is the only one that could be completely eliminated, although if the range of risk factors is broadened to include ecological and behavioral changes due to human activity, there are many other factors that could also be controlled.

In a social environment filled with stresses and frustrations, many of them driven by inequality and conflict, and constantly subjected to advertising, the consumption of psychoactive substances like tobacco and alcohol is habit-forming due to their effects on the reward circuit of the limbic system, leading to physical and psychological dependence. This system is the result of evolutionary adaptations to preserve the species, but it is also one of the causes of the repeated relapses observed when an individual tries to quit an addictive habit.12

Quitting smoking is, obviously, the most effective way to prevent tobacco-related diseases. However, insufficient efforts are made to take advantage of medical consultations, both outpatient and inpatient, to help patients begin the process of quitting smoking, which is the most frequent preventable cause of CVD and many cancers.11 The objective of this article is to provide an instrument to be used by healthcare professionals in their daily practice in the fight against smoking.

Table 2 shows the smoking-attributable risk for some diseases in the PSCs, presented as percentages of mortality and disease incidence. When smokers and never-smokers are compared, the risk of smokers is 2-3 times higher for stroke, ischemic heart disease, and peripheral vascular disease; 23 and 13 times higher for cancer in men and women, respectively; and 12-13 times higher for chronic obstructive pulmonary disease. Smokers also have a 2.87-fold higher risk of death from myocardial infarction compared with non-smokers.3

Smoking is also associated with increased blood pressure and associated complications including death and impaired renal function, and with abdominal aortic aneurysms, which have an increased risk attributable to smoking, as well as higher aneurysm growth rate in smokers compared to non-smokers. Smoking is associated with cardiac rhythm disorders including atrial fibrillation and ventricular tachycardia, and with a higher risk of heart failure and associated morbidity and mortality.13,14

The main tobacco-related diseases are coronary disease and myocardial infarction (25% higher incidence in smokers); chronic obstructive pulmonary disease (85%); lung cancer (90%); cancer of the mouth, pharynx, larynx, esophagus, stomach, pancreas, kidney, bladder, cervix, and breast (30%); and cerebrovascular disease (25%).

The risk of ischemic heart disease and associated mortality increases with number of years of smoking and number of cigarettes smoked per day, and is seen at all levels of consumption, even fewer than five cigarettes per day and passive smoking. Patients who stop smoking after coronary artery bypass surgery have a lower risk of hospitalization for heart disease. Smoking cessation is the only effective way to prevent progression of thromboangiitis obliterans, improving symptoms and reducing the lifelong risk of amputation.15,16

Smoking cessation has various benefits that should be pointed out to smokers during consultations (Table 3). Cigarette smoke contains more than 7000 chemical substances, many of which are toxic, and contributes to CVD in different ways, including adverse hemodynamic effects like increased blood pressure and heart rate, imbalance between oxygen supply and consumption, changes in coronary blood flow, endothelial dysfunction and damage, hypercoagulability and thrombosis, chronic inflammation, and lipid abnormalities, in addition to acting as a substrate for arrhythmias and cardiovascular events. These effects can be observed even in passive smokers.13,17

Smoking should be considered a chronic disease that can begin in childhood and adolescence, since about 80% of those who try tobacco do so while less than 18 years old. There is also a direct relationship between starting to smoke in childhood and continuing to smoke in adulthood. Primordial prevention, ensuring that children and adolescents do not start smoking in the first place, is an essential step in smoking control. Within a year or so of starting to smoke, children inhale the same amount of nicotine per cigarette as adults and experience the same craving for cigarettes and nicotine withdrawal symptoms, which usually develop very quickly at younger ages. One way to approach primordial prevention is by age groups, observing five main items (the “5 ‘A's”) for each group: Ask individuals about their tobacco use; Advise every smoker to quit; Assess the individual's motivation to quit and symptoms of dependence; Assist those attempting to quit smoking through counseling or therapy; and Arrange follow-up contact.19–21

In 2008 the WHO launched its MPOWER initiative,21 which has had proven impact on reducing the consumption of tobacco products. The abbreviation MPOWER is derived from the following measures: Monitor tobacco use and prevention policies; Protect people from tobacco smoke; Offer help to quit tobacco use; Warn about the dangers of tobacco; Enforce bans on tobacco advertising, promotion, and sponsorship; Raise taxes on tobacco.

These measures have an impact on smoking cessation at the population level, but most smokers require individualized treatment from healthcare professionals, often combining a behavioral approach with medications, to quit smoking altogether.

New forms of tobacco use have emerged in the last 15 years that are promoted as carrying lower or no risk. Among these are electronic cigarettes (e-cigarettes), which work by vaporizing nicotine, flavors, and other ingredients in liquid form (e-liquid) that are inhaled by the user (vaping). The most popular brand among young people in the USA is Juul, in which the e-liquid is provided in small replaceable cartridges called pod mods. These devices, now in their third generation, deliver nicotine together with vaporizing and flavoring substances. Their effects are still largely unknown but could potentially carry health risks.13,14

Against the background of sophisticated marketing campaigns promoting such new forms of tobacco use, there are currently intense discussions in both society in general and the medical community about the potential risk of e-cigarettes as a cause of CVD and cancer. Although the available epidemiological evidence is not extensive and the risk of these new forms of smoking appears to be lower than that of the classic form of smoking, there is sufficient evidence to indicate that in the short term, they can cause endothelial dysfunction, DNA damage, oxidative stress, and temporary increases in heart rate. Long-term use appears to increase the risk of myocardial infarction, stroke, and mouth and esophageal cancer.3,13

Based on the ostensibly lower risk of e-cigarettes, they have been promoted as a way to quit smoking, but evidence is lacking for this claim. In 60% of cases, individuals smoke both regular tobacco cigarettes and e-cigarettes, which does not reduce the high risk of the former. In many cases, people use these new forms of smoking for a short time, after which they go back to the same level of smoking as before.13,14

Additionally, there are concerns among the medical community that e-cigarettes will cause young people to become addicted to nicotine, acting as a gateway to regular tobacco smoking.

Although it should be acknowledged that the currently available evidence is not robust, we recommend that people should quit all forms of tobacco use, or better still not start, including oral tobacco (chewing tobacco, snus, snuff, and dissolvable tobacco), vaping (e-cigarettes), cigarettes, cigars, cigarillos, pipes, or hookahs. It is also important to combat secondhand tobacco smoke, as it carries similar risks to smoking itself, non-smokers exposed to secondhand smoke having a 25-30% increased risk of CVD.13,14

Most smokers are aware that tobacco is harmful to their health. However, in most cases this is not sufficient incentive for them to give up smoking. Similarly, physicians recognize the harmful effects of smoking, but in daily practice tend to prioritize disease treatment instead of prevention. The initial approach should be to encourage smokers to start treatment regardless of their clinical condition and the level of their habit (Tables 4-6). The benefits of quitting smoking should be emphasized to all patients at every consultation with a healthcare professional. As many countries have restrictions on smoking in public places, it is important to raise the topic of exposure to tobacco smoke with all smokers if they live or spend time with non-smokers, especially young people who may consider smoking as normal and not harmful to their health. Furthermore, individuals with asthma may present acute worsening when exposed to secondhand tobacco smoke. Table 7 lists common measures to monitor smoking cessation.

Table 5.

Fagerström test for nicotine dependence.22

How soon after you wake up do you smoke your first cigarette?
□ Within 5 minutes	□ 6 to 30 minutes	□ 31 to 60 minutes	□ After 60 minutes
Do you find it difficult to refrain from smoking in places where it is forbidden?
□ Yes	□ No
Which cigarette would you hate most to give up?
□ The first one in the morning	□ Any other
How many cigarettes per day do you smoke?
□ 10 or less	□ 11 to 20	□ 21 to 30	□ 31 or more
Do you smoke more frequently during the first hours after waking than during the rest of the day?
□ Yes	□ No
Do you smoke when you are so ill that you are in bed most of the day?
□ Yes	□ No
Total: [0-2] Very low [3-4] Low	[5] Moderate	[6-7] High	[8-10] Very high

Most smokers require cognitive behavioral therapy (CBT) (Table 8) backed by pharmacological support to cope with withdrawal syndrome, which typically lasts between two and four weeks.

Since smoking has effects at the population level and poses risks not only for smokers but also for non-smokers, pregnant women, fetuses, and children, as well as consuming large quantities of public resources, both financial and organizational, and causes dependence in smokers in a similar fashion to those addicted to other drugs, medical care and health education are not in themselves sufficient. Legislation must aim to control the exploitation and use of tobacco in all its forms, just like any other addictive drug.

The economic interests involved in tobacco cultivation, production, processing, marketing, and advertising are large and cross national borders. This means that classifying and dealing with tobacco solely as a medical and healthcare issue is inadequate. In response, in 2003 the WHO launched the FCTC,9 since ratified by 168 countries, which have committed to observing certain principles that are to be progressively incorporated into their laws. The health sectors in all signatory countries are required to monitor the implementation of these principles and to ensure that both the general population and policy-makers remain aware of them.

The FCTC was signed and ratified by the PSCs on the following dates: Angola (June 29, 2004/September 20, 2007), Brazil (June 16, 2003/November 03, 2005), Cape Verde (February 17, 2004/October 4, 2005), Equatorial Guinea (April 1st, 2004/November 7, 2007), Guinea-Bissau (accession November 7, 2008), Mozambique (June 18, 2004/July 14, 2017), Portugal (January 9, 2004/November 8, 2005), São Tomé and Príncipe (June 18, 2004/April 12, 2006), and East Timor (May 25, 2004/December 22, 2004).24,25

Organizations focused specifically on monitoring compliance with the treaty and related political actions have emerged in many countries, such as the Alliance for Tobacco Control and Health Promotion in Brazil (http://actbr.org.br/). Non-governmental organizations, national associations and committees within medical societies and in other healthcare segments are involved in mobilizing society, coordinating actions, and keeping tobacco control measures up-to-date.24,25

Tobacco use in all forms represents a serious public health problem in terms of the prevention and treatment of chronic non-communicable diseases. General practitioners, internists, cardiologists and other specialists should identify patients who smoke, make themselves familiar with and apply all available tools to encourage smokers to seek professional help to quit smoking, and take advantage of key opportunities like a diagnosis of coronary artery disease, peripheral arterial or cerebrovascular disease, or tobacco-related cancer, to raise awareness of the dangers of tobacco among patients, their family, and opinion-formers. Increasing awareness in the general population of the risks of tobacco use makes this a favorable time to approach smokers. Treatment is now more accessible (NRT and bupropion are available in the PSCs) and can be performed at any healthcare level.

The association of CBT with pharmacological support to cope with withdrawal increases the effectiveness of interventions. Relapses are part of the smoking dependence cycle and should be viewed as a lesson that will make a subsequent attempt more likely to succeed. Cessation of smoking at any age brings health benefits to the smoker and to those around them, and physicians should always be ready to offer care, irrespective of the individual's stage in the cessation process.

New forms of tobacco use, especially using electronic systems, are far from proven to be harmless, even if they may contribute to reducing overall tobacco consumption and its harmful effects, and their use should be discouraged.

Smoking must be considered as a problem that goes beyond the damage caused to the organs affected by tobacco smoke and associated products, but is part of a series of problems produced by human society, with economic, social, cultural, and ecological aspects that affect quality of life and survival itself.

The authors have no conflicts of interest to declare.