smoking in HIV patients, and focusing on the main issue

A recent article using mathematical modeling found that smokers who have well-controlled HIV infection are much more likely to die from lung cancer than AIDS-related conditions (see doi:10.1001/jamainternmed.2017.4349 )

Details:

--they used a validated Monte Carlo microsimulation model of HIV, the CEPAC-US model (Cost-Effectiveness of Preventing AIDS Complications), which includes lots of data on distributions of CD4 counts, HIV viral loads, age, sex, smoking status, treatment, etc. Individuals are entered into the simulation model at a specified time of linkage to HIV care and their outcomes are assessed at projected death or until age 80; they modeled cohorts of 1 million men or women with specific smoking exposures at specific ages

--smoking was divided into heavy (35 cigarettes/d), moderate (18 cigs/d), and light (2 cigs/d); former smokers were considered to have stopped at the age of entry into the model

Results:

--Cumulative lung cancer mortality by age 80, in the model with complete adherence to HIV treatment and no loss to follow-up in HIV care (I am including their results for those entering HIV care at age 40, though there were minimal differences if one considers  those age 30 or 50):

      --current smokers, heavy: men 28.9%, women 27.8%

      --current smokers, moderate: men 23.0%, women 20.9%

      --current smokers, light: men 18.8%, women 16.6%

      --former smokers, heavy: men 7.9%, women 7.5%

      --former smokers, moderate: men 6.1%, women 5.2%

      --former smokers, light: men 4.3%, women 3.7%

      --never smokers: men 1.6%, women 1.2%

--as an example of the relative risks: men who entered HIV care at age 40, adhered to HIV regimen, and continued to smoke at moderate level, the cumulative mortality from lung cancer was 10 times that from HIV causes (23.0% vs 2.3%). For women, the lung cancer mortality was 8-times (20.9% vs 2.5%)

--overall: depending on smoking intensity and sex, there was a 6- to 13-fold increase in lung cancer mortality over AIDS-related mortality in smokers adherent to HIV meds

--and, in men aged 40 and moderate smokers, adherent to HIV meds, the combined cumulative mortality from lung cancer and other non-AIDS-related causes (including cardiovascular and respiratory diseases and other cancers, most of which are increased by smoking) was 79.9% vs 2.3%, a 35-times increase!! And for women, 66.6% vs 2.5%, a 27-fold increase

--for the 644,200 people living with HIV aged 20-64, there are anticipated 59,900 lung cancer deaths by age 80 (9.3% of the population). However, if those people smoking stopped (and became "former smokers"), 6900 (11.5%) of the lung cancer deaths would be averted.

--even in those who are incompletely adherent to HIV meds, the projected mortality from lung cancer equals that from AIDS-related causes.

Commentary:

--Over 40% of people living with HIV in the US smoke cigarettes (vs about 15% of the general population). Lung cancer is the leading cause of cancer deaths in those on HIV treatment. And, in 2010 in France, which has similar % of HIV-positive patients who smoke, lung cancer was the leading cause of death overall in those with HIV. There is some residual immunologic dysfunction belied by the "normal" CD4 counts often achieved. For example, some cancers (eg lung cancer) seem to continue to be more common in those with even great HIV control

--Despite the limitations of this mathematical model, this article reinforces a few items in current HIV care:

    --HIV has become a chronic disease and our thinking about it has changed: we are no longer grasping at straws to help people live a little longer, as was the case a few decades ago

    --Of course, this applies to patients who are plugged into care and adherent to their meds. Analysis from this study, not surprisingly, shows that those incompletely adherent as a group still have a significant AIDS-related mortality, which can be a little higher than lung cancer mortality (and much higher if they do not take HIV meds at all!!).  So, to the extent possible, the imperative is still to ensure that those who are HIV infected are identified and involved in treatment programs

    --one clear conclusion from this study is that smoking cessation programs should routinely be incorporated into HIV care. And one study did show that the % of smokers wanting to quit smoking was similar in HIV-positive vs negative people, suggesting that such programs may have significant benefit in smoking cessation.

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But, the real reason I bring up this article at this time is that I think there are important general lessons here:

--it is quite common that patients, especially those with complex medical histories, focus on a single problem or even a single "number". Examples include:

    --the patient with heart disease, put on a statin and gets great lipid numbers, then stops eating well and exercising ("after all, my LDL is only 72…"). Or, the diabetic patient put on meds to lower the A1c similarly reverting to a less healthy diet/exercise program as the a1C number gets better

     --the patient with diabetes, heart disease, hypertension, and smoking focusing on their diabetes control (which is probably the least likely to affect their long-term mortality, smoking conferring the highest mortality of any reversible risk factor)

--why does this happen?? Lots of potential reasons:

    --the patient has a personal association which either promotes one approach or undercuts another: their mother had diabetes and became blind/lost a limb/etc, elevating the morbidity of diabetes disproportionately in their minds. Or their grandfather who smoked every day of his life but lived til age 93.

     --the list of their problems is overwhelming, and it is psychologically too much to deal with all of them, easier to focus on one only

     --a lesser important problem is easier to fix (stopping smoking is typically really, really difficult)

     --we clinicians focus disproportionately on a single problem. that may be appropriate initially (they have opioid use disorder plus smoking, we focus on the OUD initially and appropriately, see the patient often, but don't deal with the smoking as the OUD starts getting in better control)

     --and, perhaps as an ideological issue for all of us, we in Western society often revert to a reductionist approach in looking at problems. Focusing on micronutrient deficiencies instead of looking at the diet overall ("is there a pill or vitamin I can take to fix the problem?", or, as a provider, "is there a pill I can give, perhaps an antioxidant or statin, to decrease the risk of heart disease??" instead of strongly promoting a healthy lifestyle (which is good for the whole body, not just the heart)

--one of the things I have tried to do in these blogs is to look at medical problems in a broader context (not that I am immune from the above…). The reality is:

      --most of what we take care of in Western societies (and increasingly in others) is trying to fix the outcomes of toxic environments, lifestyles, etc which are promoted in our societies (fast foods, sodas, alcohol/smoking, poor air/water/food quality, etc etc)

      --everything really is inter-related:

            --our lifestyle and environment directly affect disease, and there are indirect effects (eg changes in the microbiome related to using antibiotics, not eating healthfully/exercising, stress, etc; and these microbiome changes in themselves predispose us to diabetes, obesity, heart disease, NAFLD, etc.)

            --many of these environmental effects (in the broadest sense) reflect our social/political realities: the primary goal in our society is not public health (and even our most obvious public health initiatives are very difficult to effect—eg decreasing trans fats in our diet: it has been evident for many decades that trans fats were perhaps the single most potent cardiovascular risk factor in foods, but it took many years to pass some local initiatives to decrease trans fats in foods, and many more years to implement a national approach; this was a "no-brainer" except for the disproportionate power of industry, eg McDonalds. Or the fact that the predominant adverse effect on our microbiome is the unregulated use of antibiotics in agriculture (there are now nonbinding suggestions/pleas that farmers use antibiotics in the meat industry only to treat sick animals and not give them to all animals to improve their weights/value). And, to make matters much worse, we don't even have uniform access to health care….

So, what can one do??

--on a patient level:

    --I think one of our most important goals is to reinforce a healthy lifestyle with our patients on a regular basis, asking them what they are doing, what they think they should do, what they think they can do, and try to make incremental changes with them

    --for pateints who focus on their "numbers" (LDL, A1c) etc, or do not prioritize their medical problems in a way which optimizes their health, it is really useful to have them explain their health beliefs, their explanatory model: "what is your understanding of diabetes?"  "of all of your medical problems, what do you think is the one that is likely to harm you the most?"  "you are doing great in terms of lowering your LDL, so what do you now think is the most important health issue you have, and why?" In this context, I do think that motivational interviewing is really pivotal: it really assesses where the patient is at, what their understanding is, how they think they can move forward, and ultimately it empowers them to do so

    --these are the really hard (and, I think, important issues) in primary care, and often take lots of time, frequent primary care visits, etc (not a single discussion and "come back in 6 months"). But I do think these interventions are probably some of the most important for patients' morbidity/mortality and also happiness/self-efficacy

    ​--and, I think, for us overall to be less focused on the newest drug, vitamin etc as the magic bullet which will really help patients (we certainly do have lots of very effective and important drugs, and we should use them as needed, but I think it is helpful to "step back" every now and then and think about the individual patient, their social context, and what the "big picture" issues are for them) 

--on a social level: do what we can to help forward sociopolitical changes which would help forward initiatives to improve public health and patient access to health care, whether that be education to empower patients or communities to improve their public health (eg getting rid of billboards promoting alcohol or cigarettes, etc: ie, helping communities identify the major public health problems and developing a sustainable solution), working more globally to get rid of harmful food additives/environmental exposures (eg trans fats, smog exposure) or on initiatives promoting universal health care, helping transform our medical system and general ideology to promote public health or primary care over the newest, expensive, perhaps not-so-well researched specialty intervention that might help a few people live a little longer with their end-stage disease, etc etc


see http://gmodestmedblogs.blogspot.com/2015/01/community-wide-rural-cardiac-health.html​ for a blog about a really great community-initiated and run, long-term public health initiative to decrease cardiovascular disease in a poor, rural Maine community