An expansive harm reduction approach for people with HIV who smoke tobacco and are unable or unwilling to quit should be employed, a team of US experts argue in The Lancet HIV. The limited success of smoking cessation strategies in this population brings them to propose this approach. Harm reduction would encompass cutting down on cigarette intake, and also reducing the health consequences of smoking through more lung cancer screening and better control of cardiovascular health.
“We hope this Viewpoint will help to begin shifting the idea of tobacco treatment in the setting of comprehensive HIV care from a strictly all-or-none cessation approach, which succeeds for only a small minority of smokers living with HIV, to a harm reduction approach that might extend substantial benefit to both those who are able to quit and to the majority who continue smoking,” they say.
In the US and Europe, tobacco use is now a leading killer of people with HIV. These regions have the highest prevalence of tobacco use among people with HIV. However, in lower and middle-income countries, the prevalence of cigarette smoking is also significantly higher among people with HIV than among HIV-negative individuals.
This grim context warrants an ongoing reflection on how to best tackle tobacco smoking among people with HIV, to which Professor Jonathan Shuter from the Albert Einstein College of Medicine in New York City and colleagues contribute. They describe lifelong abstinence from smoking as the ideal goal and stress that adopting harm reduction should not be perceived as minimising that.
“Nonetheless,” they say, “it would be unrealistic to ignore the facts.”
Getting people with HIV to quit smoking is difficult and most attempts end in failure. Multiple randomised controlled trials of evidence-based tobacco treatments have been completed in people with HIV. Unfortunately, only three of them have demonstrated efficacy in promoting abstinence after at least six months. Two used an intensive behavioural intervention, and one provided varenicline, a drug known to block the pleasant effect of smoked nicotine on the brain. However, in these trials, the proportion quitting smoking ranged from as low as 12 to 15%, although they were considered successful in this challenging context. In other words, even with aggressive therapy combining intensive behavioural treatment with medications, most smokers with HIV will continue to smoke.
Focusing on smoking cessation as the unique goal for people with HIV and their healthcare providers is therefore questionable, and a harm reduction approach may be preferable. In the context of tobacco, harm reduction mainly focuses on reducing average daily cigarette intake (cutting down). It also encompasses transitioning to alternative tobacco or nicotine products that are less harmful and preventive efforts in relation to lung cancer and cardiovascular health.
Cutting down on cigarettes
According to Shuter and colleagues, cutting down on cigarettes is a realistic goal for most smokers, and there is increasing evidence that smoking less decreases tobacco-related mortality and morbidity. For example, it is estimated that light smokers with HIV have a 35% reduction in lung cancer mortality, compared to heavy smokers. Large cohort studies have shown that the higher the number of cigarettes smoked per day, the higher the cardiovascular disease risk and mortality.
Also, and importantly, robust literature suggests that reducing cigarettes per day predicts future cessation and is a frequent action towards that goal.
Nicotine replacement therapy and e-cigarettes
Turning to nicotine replacement therapy, a 2016 meta-analysis of various harm reduction strategies concluded that there was sufficient evidence proving that the method could reduce cigarettes per day in those who do not wish to quit. The other interventions examined, such as snus use or behavioural therapy, may have done as well, but the data were insufficient to reach any such conclusion.
"Even with aggressive therapy combining intensive behavioural treatment with medications, most smokers with HIV will continue to smoke."
In two of the aforementioned clinical trials, with Professor Shuter as a leading investigator, an intensive smoking cessation programme was compared with a minimal one. In both arms, all participants received a 12-week course of nicotine replacement therapy. In terms of smoking cessation, the intensive programme proved more successful than the minimal one. However, when quitters were excluded from the analysis, it was found that 70% of remaining participants had reduced, 16% had not changed, and 14% had increased their cigarettes per day. Notably, participants in the minimal programme reduced their daily intake at similar rates to those in the intensive programmes. Therefore, nicotine replacement therapy quite probably had an impact on daily intake of cigarettes.
E-cigarettes may represent an additional tool to help decrease smoking. Research in the general population supports their efficacy in reducing cigarette intake. However, little is known about their effect on tobacco use in people with HIV, with just one small pilot study with 19 cigarette smokers living with HIV. That study reported a significant decrease in cigarettes per day and an increase in motivation to quit.
A few trials are planned to study e-cigarettes as harm reduction devices in people with HIV, and their results are urgently needed.
Research must also look at smokeless tobacco products – chewing tobacco or snus – which are recognised means to reduce the risk of cancer, cardiovascular disease and lung disease among smokers in general. But these products are also associated with head and neck cancers, to which people with HIV are particularly susceptible.
Lung cancer screening
Lung cancer screening and lowering the risk of cardiovascular disease are equally important in the proposed harm-reduction approach.
“Aside from smoking cessation,” say the authors, “increased use of low-dose computed tomography screening in people living with HIV who are smokers is the most realistic route to reducing lung cancer mortality, the leading cause of cancer-related deaths in people living with HIV in the USA.”
Low-dose computed tomography is a procedure that uses a computer linked to an X-ray machine, giving off a very low dose of radiation to make a series of detailed pictures of areas inside the body. The pictures are taken from different angles and used to create 3-D views of tissues and organs.
Screening is underused in people living with HIV, although a 2020 meta-analysis reported that the technique almost tripled the odds of detecting lung cancer at an early stage, which decreased mortality by 16%.
As smokers with HIV develop lung cancer at younger ages and having smoked less than HIV-negative smokers, some experts from the US recommend earlier screening at a lower cigarettes pack-year threshold. If applied, the standard approach of lung cancer screening for smokers over 55 years old with more than 30 pack-years of smoking history would be replaced by screening in smokers over 45 years old with more than 20 pack-years of smoking history.
Other benefits might be expected from screening. In an early trial of computed tomography screening for lung cancer in HIV-negative individuals, a 23% tobacco quit rate was observed during follow-up, and 58% of those quitters used a reduce-to-quit strategy.
Managing cardiovascular risk factors
Rates of hypertension and hyperlipidaemia are commonly high in people with HIV, increasing the risk of cardiovascular disease and mortality, especially in those who smoke. To reduce this risk in people with HIV, the authors recommend the following steps:
- Familiarise the HIV care providers with blood pressure and lipid targets that are appropriate for smokers living with HIV.
- Aggressively use antihypertensive medication, statins and dietary intervention to reach goals, such as systolic blood pressure <130 mm Hg and LDL cholesterol <70 mg/dL.
- Teach patients how to use the ACA/AHA score to calculate their risk of a major cardiac event in the next 10 days, and then recalculate the risk after potential intervention to show the benefits of quitting smoking, controlling blood pressure and improving the lipid profile.
Facilitating a harm reduction approach to tobacco smoking
The authors consider the latter two groups of interventions as highly feasible: “Even a busy HIV care provider can refer a patient for low-dose computed tomography screening and manage hypertension and hyperlipidaemia, or refer a patient to a primary care provider or for specialty care to reduce cardiovascular risk.”
While the authors acknowledge that their Viewpoint is largely US-focused, they also say that many of their opinions are applicable regardless of the treatment setting.
The authors also highlight a contextual element that may encourage a harm reduction approach to be embraced. The concept of harm reduction has been embedded in HIV care since it first appeared in the late 80s to encourage the mitigation of sex and substance use-related risks, and is now quite familiar to people living with HIV in the US and their healthcare providers. Therefore, one hopes that the efficacy of messages conveyed by this approach will facilitate future similar strategies in the control of tobacco smoking.