Pain, smell, and taste in adults: a narrative review of multisensory perception and interaction

Every day our sensory systems perceive and integrate a variety of stimuli containing information vital for our survival. Pain acts as a protective warning system, eliciting a response to remove harmful stimuli; it may also be a symptom of an illness or present as a disease itself. There is a growing need for additional pain-relieving therapies involving the multisensory integration of smell and taste in pain modulation, an approach that may provide new strategies for the treatment and management of pain. While pain, smell, and taste share common features and are strongly linked to emotion and cognition, their interaction has been poorly explored. In this review, we provide an overview of the literature on pain modulation by olfactory and gustatory substances. It includes adult human studies investigating measures of pain threshold, tolerance, intensity, and/or unpleasantness. Due to the limited number of studies currently available, we have structured this review as a narrative in which we comment on experimentally induced and clinical pain separately on pain-smell and pain-taste interaction. Inconsistent study findings notwithstanding, pain, smell, and taste seem to interact at both the behavioral and the neural levels. Pain intensity and unpleasantness seem to be affected more by olfactory substances, whereas pain threshold and tolerance are influenced by gustatory substances. Few pilot studies to date have investigated these effects in clinical populations. While the current results are promising for the future, more evidence is needed to elucidate the link between the chemical senses and pain. Doing so has the potential to improve and develop novel options for pain treatment

The toolish hand illusion: embodiment of a tool based on similarity with the hand

A tool can function as a body part yet not feel like one: Putting down a fork after dinner does not feel like losing a hand. However, studies show fake body-parts are embodied and experienced as parts of oneself. Typically, embodiment illusions have only been reported when the fake body-part visually resembles the real one. Here we reveal that participants can experience an illusion that a mechanical grabber, which looks scarcely like a hand, is part of their body. We found changes in three signatures of embodiment: the real hand’s perceived location, the feeling that the grabber belonged to the body, and autonomic responses to visible threats to the grabber. These findings show that artificial objects can become embodied even though they bear little visual resemblance to the hand

Unpleasant olfactory and gustatory stimuli increase pain unpleasantness in patients with chronic oral burning pain: an exploratory study

Background: Despite mounting evidence for the powerful influence of smell and taste substances in experimental pain, our knowledge of their effects in the clinical context is scarce, especially for patients with chronic oral burning pain. To fill this gap, we investigated the effect of olfactory and gustatory stimuli on pain perception in patients with chronic oral burning pain, a disabling condition that is difficult to manage and treat. Methods: Twenty-two patients with chronic oral burning pain underwent testing with a variety of olfactory and gustatory substances (pleasant, neutral, unpleasant) in multisensory interaction. The order of testing was randomized. Perception of pain intensity and unpleasantness was evaluated on a numerical rating scale at baseline and immediately after each test trial. Results: Pain unpleasantness but not pain intensity was found to be modulated by chemosensory stimuli. Unpleasant olfactory and gustatory stimuli increased the perception of pain unpleasantness compared to pleasant and neutral stimuli. Pain unpleasantness after unpleasant olfactory and gustatory stimuli correlated with psychological questionnaire subscale scores for distress (CORE-OM) and emotional awareness (TAS-20). Conclusions: Our findings suggest a role of unpleasant chemosensory stimuli in increasing the perception of pain unpleasantness in patients with chronic oral burning. The lack of an effect on pain intensity indicates a dissociation between sensory and affective pain components. Future research is needed to further study the association between chemosensory stimuli and emotional and subjective aspects in modulating chronic oral burning pain

Clinical and psychological characteristics associated with negative beliefs and concerns about treatment necessity in rheumatic diseases

Identifying factors that influence problematic beliefs and behaviors related to pharmacotherapy may be useful for clinicians to improve the patients' adherence. The study aims to assess patients' beliefs about the necessity and concerns regarding pharmacotherapy in rheumatic diseases and attitude styles, and to investigate the association between clinical factors and negative beliefs about medication. A sample of 712 patients affected by Rheumatoid Arthritis, Psoriatic Arthritis, Ankylosing Spondylitis was enrolled. They were assessed using the Beliefs about Medicines Questionnaires-Specific (BMQ), the Simplified Disease Activity Index (SDAI), the Visual Analogue Scale for pain (VAS), the Chalder Fatigue Scale (CFQ) and the Health Assessment Questionnaire-Disability Index (HAQ-DI). The balance between benefits and costs in the BMQ-Specific was positive in the 79.4% of patients, negative in the 12.1% and equal in the 8.6%. SDAI, taking more than 5 medications, taking anti interleukin 6 (Anti-IL6) or biological disease-modifying antirheumatic drugs (bDMARDs), or targeted synthetic disease-modifying antirheumatic drugs (tsDMARDs), pain, and fatigue were significantly associated to higher Concerns. Having a longer disease duration was significantly associated with a higher Necessity, together with the current pharmacological treatments and the disability. The multivariate regression models estimated that higher pain and fatigue were associated to higher Concerns (p < 0.001), while a longer disease duration (p < 0.001) and all pharmacological treatments for a rheumatologic disease (p = 0.001) were associated to higher Necessity levels. A high length of disease, a low level of remission, a high number of total medications, the prescription of an Anti-IL6/bDMARDs/tsDMARDs drug, a high level of pain, fatigue and disability identified patients potentially less adherent to pharmacotherapy to be carefully looked after by clinicians

Hedonicity in functional motor disorders: a chemosensory study assessing taste

The aim of this study was to explore hedonicity to basic tastes in patients with functional motor disorders (FMDs) that are often associated with impairment in emotional processing. We recruited 20 FMD patients and 24 healthy subjects, matched for age and sex. Subjects were asked to rate the hedonic sensation (i.e., pleasant, neutral, and unpleasant) on a\u2009-\u200910 to +10 scale to the four basic tastes (sweet, sour, salty, and bitter) at different concentrations, and neutral stimuli (i.e., no taste stimulation) by means of the Taste Strips Test. Anxiety, depression, and alexithymia were assessed. FMD patients rated the highest concentration of sweet taste (6.7\u2009\ub1\u20092.6) as significantly more pleasant than controls (4.7\u2009\ub1\u20092.5, p\u2009=\u20090.03), and the neutral stimuli significantly more unpleasant (patients:\u2009-\u20090.7\u2009\ub1\u20090.4, controls: 0.1\u2009\ub1\u20090.4, p\u2009=\u20090.013). Hedonic ratings were not correlated to anxiety, depression, or alexithymia scores. Hedonic response to taste is altered in FMD patients. This preliminary finding might result from abnormal interaction between sensory processing and emotional valence

Laparoscopy versus laparotomy for FIGO stage 1 ovarian cancer (Review)

Background This is an updated version of the original review that was first published in the Cochrane Database of Systematic Reviews 2008, Issue 4. Laparoscopy has become an increasingly common approach to surgical staging of apparent early-stage ovarian tumours. This review was undertaken to assess the available evidence on the benefits and risks of laparoscopy compared with laparotomy for the management of International Federation of Gynaecology and Obstetrics (FIGO) stage I ovarian cancer. Objectives To evaluate the benefits and risks of laparoscopy compared with laparotomy for the surgical treatment of FIGO stage I ovarian cancer (stages Ia, Ib and Ic). Search methods For the original review, we searched the Cochrane Gynaecological Cancer Group Trials (CGCRG) Register, Cochrane Central Register of Controlled Trials (CENTRAL 2007, Issue 2), MEDLINE, EMBASE, LILACS, Biological Abstracts and CancerLit from 1 January 1990 to 30 November 2007. We also handsearched relevant journals, reference lists of identified studies and conference abstracts. For this updated review, we extended the CGCRG Specialised Register, CENTRAL, MEDLINE, EMBASE and LILACS searches to 6 December 2011. Selection criteria Randomised controlled trials (RCTs), quasi-RCTs and prospective cohort studies comparing laparoscopic staging with open surgery (laparotomy) in women with stage I ovarian cancer according to FIGO. Data collection and analysis There were no studies to include, therefore we tabulated data from non-randomised studies (NRS) for discussion. Main results We performed no meta-analyses. Authors’ conclusions This review has found no good-quality evidence to help quantify the risks and benefits of laparoscopy for the management of earlystage ovarian cancer as routine clinical practice

Laparoscopy versus laparotomy for FIGO stage 1 ovarian cancer (Review)

Background Over the past ten years laparoscopy has become an increasingly common approach for the surgical removal of early stage ovarian tumours. There remains uncertainty about the value of this intervention. This review has been undertaken to assess the available evidence of the benefits and harms of laparoscopic surgery for the management of early stage ovarian cancer compared to laparotomy. Objectives To evaluate the benefits and harms of laparoscopy in the surgical treatment of FIGO stage I ovarian cancer (stages Ia, Ib and Ic) when compared with laparotomy. Search methods Trials were identified by searching the Cochrane Gynaecological Cancer Group Trials Register, Cochrane Central Register of Controlled Trials (CENTRAL),TheCochrane Library Issue 2, 2007,MEDLINE (January 1990 toNovember 2007), EMBASE (1990 toNovember 2007), LILACS (1990 toNovember 2007), BIOLOGICALABSTRACTS (1990 toNovember 2007) andCancerlit (1990 toNovember 2007). We also searched our own publication archives, based on prospective handsearching of relevant journals from November 2007. Reference lists of identified studies, gynaecological cancer handbooks and conference abstract were also scanned. Selection criteria Studies including patients with histologically proven stage I ovarian cancer according to the International Federation of Gynaecology and Obstetrics (FIGO). Studies comparing laparoscopic surgery with laparotomy for early stage ovarian cancer were only available from1990. It was anticipated that a very small number of randomised controlled trials (RCTs) were conducted studying themanagement of early stage ovarian cancer. Therefore, non-randomised comparative studies, cohort studies and case-controls studies, but not studies with historical controls, were also considered. Data collection and analysis Data extraction was performed independently by five review authors (LRM, DDR, MIR, MCB and MIE) who assessed study quality and quality of extracted data. Extracted data included trial characteristics, characteristics of the study participants, interventions and outcomes. The quality of non RCTs was assessed using appropriate quality evaluations tools from the Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) and from the Newcastle-Ottawa tool for observational studies (NOS). Main results No RCTs were identified. Three observational studies were identified. Authors’ conclusions This review has found no evidence to help quantify the value of laparoscopy for the management of early stage ovarian cancer as routine clinical practice

Correlation between olfactory function, age, sex, and cognitive reserve index in the Italian population

Purpose: Loss of smell decreases the quality of life and contributes to the failure in recognizing hazardous substances. Given the relevance of olfaction in daily life, it is important to recognize an undiagnosed olfactory dysfunction to prevent these possible complications. Up to now, the prevalence of smell disorders in Italy is unknown due to a lack of epidemiological studies. Hence, the primary aim of this study was to evaluate the prevalence of olfactory dysfunction in a sample of Italian adults. Methods: Six hundred and thirty-three participants (347 woman and 286 men; mean age 44.9 years, SD 17.3, age range 18-86) were recruited from 10 distinct Italian regions. Participants were recruited using a convenience sapling and were divided into six different age groups: 18-29 years (N = 157), 30-39 years (N = 129), 40-49 years (N = 99), 50-59 years (N = 106), > 60 years (N = 142). Olfactory function, cognitive abilities, cognitive reserve, and depression were assessed, respectively, with: Sniffin' Sticks 16-item Odor Identification Test, Montreal Cognitive Assessment, Cognitive Reserve Index, and the Beck Depression Inventory. Additionally, socio-demographic data, medical history, and health-related lifestyle information were collected. Results: About 27% of participants showed an odor identification score < 12 indicating hyposmia. Multiple regression analysis revealed that OI was significantly correlated with age, sex, and cognitive reserve index, and young women with high cognitive reserve index showing the highest olfactory scores. Conclusion: This study provides data on the prevalence of olfactory dysfunction in different Italian regions

Pulmonary Artery Catheter Monitoring in Patients with Cardiogenic Shock: Time for a Reappraisal?

Cardiogenic shock represents one of the most dramatic scenarios to deal with in intensive cardiology care and is burdened by substantial short-term mortality. An integrated approach, including timely diagnosis and phenotyping, along with a well-established shock team and management protocol, may improve survival. The use of the Swan-Ganz catheter could play a pivotal role in various phases of cardiogenic shock management, encompassing diagnosis and haemodynamic characterisation to treatment selection, titration and weaning. Moreover, it is essential in the evaluation of patients who might be candidates for long-term heart-replacement strategies. This review provides a historical background on the use of the Swan-Ganz catheter in the intensive care unit and an analysis of the available evidence in terms of potential prognostic implications in this setting