Helping patients with Crohn's disease quit smoking

The effect of a multidisciplinary approach for smoking cessation in patients with Crohn's disease: Results from an observational cohort study

INTRODUCTION

Cigarette smoking is the most important risk factor for Crohn’s disease (CD). The effectiveness of smoking cessation programs (SCPs) in patients with CD is still poorly understood.

METHODS

This was a retrospective, observational, single-centre, cohort study of 136 active smokers with mean age 55 years (SD=11), 58% males, including 27 (19.8%) patients with CD who entered the multidisciplinary SCP of the Luigi Sacco University Hospital of Milan from January 2017 through January 2019. A pulmonologist was responsible for the clinical and pharmacological management, while a psychiatrist and a psychologist conducted the counselling and assessed the motivation to quit, anxiety and depression using the Brief Psychiatric Rating Scale (BPRS) and the nicotine dependence with the Fagerström test. Patients were defined as quitters after 12 months.

RESULTS

Demographic and clinical characteristics, and Fagerström score, did not differ in patients with and without CD. At baseline, patients with CD had a higher BPRS (median: 27, IQR: 22–32; vs 25 and 22–28.5; p=0.03), and a lower motivation to quit score (median: 10, IQR: 9–13; vs 14 and 12–15; p<0.001). After 12 months, the quitting rate of smokers with CD was significantly lower (14.8% vs 36.7%; p<0.022) and the chance of quitting was negatively associated with the baseline BPRS (r=-0.256; p<0.003). Varenicline and nicotine replacement therapy tended to be less effective in patients with CD.

CONCLUSIONS

The lower efficacy of SCPs in patients with CD might be secondary to a higher prevalence of anxiety and depression. Psychological issue recognition and support should be enhanced to increase SCP effectiveness in CD.

The Neuromodulation of the Intestinal Immune System and Its Relevance in Inflammatory Bowel Disease

One of the main tasks of the immune system is to discriminate and appropriately react to “danger” or “non-danger” signals. This is crucial in the gastrointestinal tract, where the immune system is confronted with a myriad of food antigens and symbiotic microflora that are in constant contact with the mucosa, in addition to any potential pathogens. This large number of antigens and commensal microflora, which are essential for providing vital nutrients, must be tolerated by the intestinal immune system to prevent aberrant inflammation. Hence, the balance between immune activation versus tolerance should be tightly regulated to maintain intestinal homeostasis and to prevent immune activation indiscriminately against all luminal antigens. Loss of this delicate equilibrium can lead to chronic activation of the intestinal immune response resulting in intestinal disorders, such as inflammatory bowel diseases (IBD). In order to maintain homeostasis, the immune system has evolved diverse regulatory strategies including additional non-immunological actors able to control the immune response. Accumulating evidence strongly indicates a bidirectional link between the two systems in which the brain modulates the immune response via the detection of circulating cytokines and via direct afferent input from sensory fibers and from enteric neurons. In the current review, we will highlight the most recent findings regarding the cross-talk between the nervous system and the mucosal immune system and will discuss the potential use of these neuronal circuits and neuromediators as novel therapeutic tools to reestablish immune tolerance and treat intestinal chronic inflammation.

Anti-inflammatory effects of the nicotinergic peptides SLURP-1 and SLURP-2 on human intestinal epithelial cells and immunocytes

A search for novel and more efficient therapeutic modalities of inflammatory bowel disease (IBD) is one of the most important tasks of contemporary medicine. The anti-inflammatory action of nicotine in IBD might be therapeutic, but its toxicity due to off-target and nonreceptor effects limited its use and prompted a search for nontoxic nicotinergic drugs. We tested the hypothesis that SLURP-1 and -2—the physiological nicotinergic substances produced by the human intestinal epithelial cells (IEC) and immunocytes—can mimic the anti-inflammatory effects of nicotine. We used human CCL-241 enterocytes, CCL-248 colonocytes, CCRF-CEM T-cells, and U937 macrophages. SLURP-1 diminished the TLR9-dependent secretion of IL-8 by CCL-241, and IFNγ-induced upregulation of ICAM-1 in both IEC types. rSLURP-2 inhibited IL-1β-induced secretion of IL-6 and TLR4- and TLR9-dependent induction of CXCL10 and IL-8, respectively, in CCL-241. rSLURP-1 decreased production of TNFα by T-cells, downregulated IL-1β and IL-6 secretion by macrophages, and moderately upregulated IL-10 production by both types of immunocytes. SLURP-2 downregulated TNFα and IFNγR in T-cells and reduced IL-6 production by macrophages. Combining both SLURPs amplified their anti-inflammatory effects. Learning the pharmacology of SLURP-1 and -2 actions on enterocytes, colonocytes, T cells, and macrophages may help develop novel effective treatments of IBD.

Anti-inflammatory effects of nicotine in obesity and ulcerative colitis

Cigarette smoke is a major risk factor for a number of diseases including lung cancer and respiratory infections. Paradoxically, it also contains nicotine, an anti-inflammatory alkaloid. There is increasing evidence that smokers have a lower incidence of some inflammatory diseases, including ulcerative colitis, and the protective effect involves the activation of a cholinergic anti-inflammatory pathway that requires the α7 nicotinic acetylcholine receptor (α7nAChR) on immune cells. Obesity is characterized by chronic low-grade inflammation, which contributes to insulin resistance. Nicotine significantly improves glucose homeostasis and insulin sensitivity in genetically obese and diet-induced obese mice, which is associated with suppressed adipose tissue inflammation. Inflammation that results in disruption of the epithelial barrier is a hallmark of inflammatory bowel disease, and nicotine is protective in ulcerative colitis. This article summarizes current evidence for the anti-inflammatory effects of nicotine in obesity and ulcerative colitis. Selective agonists for the α7nAChR could represent a promising pharmacological strategy for the treatment of inflammation in obesity and ulcerative colitis. Nevertheless, we should keep in mind that the anti-inflammatory effects of nicotine could be mediated via the expression of several nAChRs on a particular target cell.

Cytokine-induced alterations of α7 nicotinic receptor in colonic CD4 T cells mediate dichotomous response to nicotine in murine models of Th1/Th17- versus Th2-mediated colitis

Ulcerative colitis (UC) and Crohn's disease (CD) are two forms of chronic inflammatory bowel disease. CD4 T cells play a central role in the pathogenesis of both diseases. Smoking affects both UC and CD but with opposite effects, ameliorating UC and worsening CD. We hypothesized that the severity of gut inflammation could be modulated through T cell nicotinic acetylcholine receptors (nAChRs) and that the exact clinical outcome would depend on the repertoire of nAChRs on CD4 T cells mediating each form of colitis. We measured clinical and immunologic outcomes of treating BALB/c mice with oxazolone- and trinitrobenzene sulfonic acid (TNBS)-induced colitides by nicotine. Nicotine attenuated oxazolone colitis, which was associated with an increased percentage of colonic regulatory T cells and a reduction of Th17 cells. TCR stimulation of naive CD4(+)CD62L(+) T cells in the presence of nicotine upregulated expression of Foxp3. In marked contrast, nicotine worsened TNBS colitis, and this was associated with increased Th17 cells among colonic CD4 T cells. Nicotine upregulated IL-10 and inhibited IL-17 production, which could be abolished by exogenous IL-12 that also abolished the nicotine-dependent upregulation of regulatory T cells. The dichotomous action of nicotine resulted from the up- and downregulation of anti-inflammatory α7 nAChR on colonic CD4 T cells induced by cytokines characteristic of the inflammatory milieu in oxazolone (IL-4) and TNBS (IL-12) colitis, respectively. These findings help explain the dichotomous effect of smoking in patients with UC and CD, and they underscore the potential for nicotinergic drugs in regulating colonic inflammation.

The impact of smoking in Crohn's disease: no smoke without fire

Smoking habit is the most widely accepted environmental factor affecting the incidence and disease progression in the inflammatory bowel diseases. The contrasting effects in Crohn's disease (CD) and ulcerative colitis are unexplained. The purpose of this review is to summarise the existing data on the effects of smoking in CD on disease history, recurrence after surgery, effects on drug responses and to review available evidence that carriage of some of the known susceptibility genes may be disproportionate in smokers with CD. The review also highlights potential mechanisms involved and factors that might affect patients' smoking habits. The clinical and scientific implications of the data are discussed.

Neuronal nicotinic acetylcholine receptor expression and function on nonneuronal cells

Of the thousands of proven carcinogens and toxic agents contained within a cigarette, nicotine, while being the addictive agent, is often viewed as the least harmful of these compounds. Nicotine is a lipophilic molecule whose effects on neuronal nicotinic acetylcholine receptors (nAChR) have been primarily focused on its physiologic impact within the confines of the brain and peripheral nervous system. However, recently, many studies have found neuronal nAChRs to be expressed on many different nonneuronal cell types throughout the body, where increasing evidence suggests they have important roles in determining the consequences of nicotine use on multiple organs systems and diseases as diverse as ulcerative colitis, chronic pulmonary obstructive disease, and diabetes, as well as the neurologic disorders of Parkinson's and Alzheimer's disease. This review highlights current evidence for the expression of peripheral nAChRs in cells other than neurons and how they participate in fundamental processes, such as inflammation. Understanding these processes may offer novel therapeutic strategies to approach inflammatory diseases, as well as precautions in the design of interventional drugs.

Factors affecting health related quality of life of patients with inflammatory bowel disease

Using a disease specific instrument to measure the health related quality of life (HRQOL) of patients with inflammatory bowel disease (IBD), it has been shown that their perceived HRQOL worsens during active disease. The precise factors involved in HRQOL changes reported by these patients are largely unknown. Our aim was to elucidate which socio-demographic and health status variables are related with HRQOL in IBD patients. To this end, 354 patients with IBD were interviewed. To quantify the impairment in the HRQOL, the 36-item version of the inflammatory bowel disease questionnaire (IBDQ) was administered to all patients. To explore the relation of each individual variable on the HRQOL an univariate analysis by using the Spearman correlation, the Mann-Whitney or the Kruskal-Wallis test was performed when necessary. Factors significant at the univariate analysis were assessed using multiple linear regression modeling with global IBDQ score as the dependent factor.

RESULTS

Disease type did not predict IBDQ score in the univariate nor in the multivariate analysis. Consequently, statistical analysis was performed in the global group of 354 patients independently of the type of disease. Lower recurrence/year index, longer disease duration, higher level of education, symptom activity, male gender and non-necessity of hospitalization all predict a better HRQOL (p < 0.05). Factors which remained significant (p < 0.05) in the multiple regression modeling were gender, need of hospitalization, symptomatic activity, recurrence/year index and education level.

CONCLUSIONS

Symptomatic activity and socio-demographic variables such as gender and education are the most important factors involved in the impairment of HRQOL in patients with IBD.

Attitudes toward smoking and smoking behaviors of patients with Crohn's disease

OBJECTIVE

To examine the smoking behaviors of people with Crohn's disease. In active smokers, we measured their willingness to quit, their degree of nicotine dependence, and the proportion that made a quit attempt within 6 months to determine if they were refractory to smoking cessation in comparison to the general population. We also examined factors that were important in their decision to smoke.

METHODS

We conducted a cross-sectional survey of out-patients, supplemented by telephone interviews and a 6-month follow-up questionnaire of active smokers. Measures included disease activity, current smoking behaviors, intentions (stage of change), Fagerstrom Test for Nicotine Dependence, and factors related to their decision to smoke (decisional balance).

RESULTS

The questionnaire was completed by 115 patients (78% response rate). Forty percent were active smokers. Of active smokers, 59% were considering quitting within the next 6 months, and of these, 15% were planning on quitting within the next 30 days. Those with moderate disease activity were more likely to be considering quitting than those with mild or severe activity. Nicotine dependence was rated as high in 33% and as moderate in 43%. Factors unrelated to Crohn's disease were more important in their decision to smoke than were Crohn's disease-related factors. After 6 months, 23% had made an attempt to quit and this attempt was strongly associated with their stated intentions at the baseline questionnaire. Two of three patients who had recently quit at baseline had resumed smoking.

CONCLUSION

When compared to similar data for the general population, patients with Crohn's disease are no more refractory to smoking cessation.