Risk factors and outcomes of chronic opioid use following trauma.

BACKGROUND: The growing problem of opioid misuse has become a serious crisis in many countries. The role of trauma as a gateway to opioid use is currently not determined. The study was undertaken to assess whether traumatic injury might be associated with chronic opioid use and accompanying increased long-term mortality. METHODS: Injured patients and controls from Sweden were matched for age, sex and municipality. After linkage to Swedish health registers, opioid consumption was assessed before and after trauma. Among injured patients, logistic regression was used to investigate factors associated with chronic opioid use, assessed by at least one written and dispensed prescription in the second quarter after trauma. Cox regression was employed to study excess risk of mortality. In addition, causes of death for postinjury opioid users were explored. RESULTS: Some 13 309 injured patients and 70 621 controls were analysed. Exposure to trauma was independently associated with chronic opioid use (odds ratio 3·28, 95 per cent c.i. 3·02 to 3·55); this use was associated with age, low level of education, somatic co-morbidity, psychiatric co-morbidity, pretrauma opioid use and severe injury. The adjusted hazard ratio for death from any cause 6-18 months after trauma for chronic opioid users was 1·82 (95 per cent c.i. 1·34 to 2·48). Findings were similar in a subset of injured patients with no pretrauma opioid exposure. CONCLUSION: Traumatic injury was associated with chronic opioid use. These patients have an excess risk of death in the 6-18 months after trauma.

ANTECEDENTES: El uso indebido de opioides es un problema creciente que se ha convertido en una grave crisis en muchos países. No se ha analizado el papel de las lesiones traumáticas como puerta de entrada al uso de opioides. Se estableció la hipótesis de que una lesión traumática podría asociarse con el uso crónico de opioides y acompañarse de un aumento de la mortalidad a largo plazo. MÉTODOS: Se ajustaron por edad, sexo y municipio a los pacientes suecos con lesiones traumáticas y sus controles. Después de vincular varios registros de salud suecos, se evaluó el consumo de opioides antes y después de la lesión traumática. En los pacientes con lesiones traumáticas, se utilizó una regresión logística para definir los factores asociados con el uso crónico de opioides, definida como una receta prescrita y dispensada en el segundo trimestre después de la lesión traumática, y ​​una regresión de Cox para estudiar el exceso de riesgo de mortalidad. Además, se exploraron las causas de muerte de los usuarios de opioides postraumáticos. RESULTADOS: Se analizaron 13.309 pacientes con lesiones traumáticas y 70.621 controles. La exposición a una lesión traumática se asoció de forma independiente con el uso crónico de opioides, (razón de oportunidades, odds ratio, OR) OR 3,3 (i.c. del 95% 3,0-3,6), y dicho uso se asoció con la edad, el bajo nivel educativo, las comorbilidad físicas y psiquiátricas, el uso previo de opioides y la gravedad de las lesiones. El cociente de riesgos instantáneos, hazard ratio, HR ajustado de muerte por cualquier causa a los 6-18 meses de la lesión traumática para los consumidores crónicos de opioides fue de 1,8 (i.c. del 95% 1,3-2,5). En un subconjunto de pacientes con lesiones traumáticas sin exposición previa a los opioides, los hallazgos fueron similares. CONCLUSIÓN: La lesión traumática se asoció con el uso crónico de opioides. Estos pacientes presentan un exceso de riesgo de mortalidad entre los 6 y 8 meses después del trauma.

Socio-economic burden of patients with a diagnosis related to chronic pain--register data of 840,000 Swedish patients.

BACKGROUND: Chronic pain constitutes a substantial socio-economic challenge but little is known about its actual cost. AIM: To estimate the direct and indirect costs of patients with a diagnosis related to chronic pain (DRCP), to determine variation in these costs across different diagnosis groups, and to identify what resources constitute the most important components of costs. METHODS: Patient level data from three administrative registries in Västra Götalandsregionen in Sweden including inpatient and outpatient care, prescriptions, long-term sick-leaves, and early retirement were extracted. Patients with a DRCP between January 2004 and November 2009 were selected. RESULTS: In total, 840,000 patients with a DRCP were identified. The mean total costs per patient and year were estimated at 6400 EUR but were higher for patients with cancer (10,400 EUR). Patients on analgesic drugs had more than twice as high costs as patients without analgesic drugs, on average. Indirect costs (sick-leaves and early retirement) constituted the largest cost component (59%) followed by outpatient (21%) and inpatient care (14%), whereas analgesic drug prescriptions constituted less than 1 percent of the total. CONCLUSIONS: The socio-economic burden of patients with a diagnosis related to chronic pain amounts to 32 billion EUR per year, when findings from Västra Götalandsregionen are extrapolated to the whole of Sweden. This compares to a fifth of the total Swedish tax burden in 2007 or about a tenth of Swedish GDP. This study does not provide evidence on what costs are caused by chronic pain per se. However, the higher costs of patients on analgesic drugs might indicate that the consequences of pain are of major importance.

Procedure-related pain among adult patients with hematologic malignancies.

BACKGROUND: Cancer patients undergo numerous invasive diagnostic procedures. However, there are only sparse data on the characteristics and determinants for procedure-related pain among adult cancer patients. METHODS: In this prospective study, we evaluated the characteristics and determinants of procedure-related pain in 235 consecutive hematologic patients (M/F:126/109; median age 62 years, range 20-89 years) undergoing a bone marrow aspiration/biopsy (BMA) under local anesthesia. Questionnaires were used to assess patients before-, 10 min and 1-7 days post BMA. Using logistic regression models, we calculated odds ratios (ORs) and 95% confidence intervals (CIs). RESULTS: 165/235 (70%) patients reported pain during BMA; 92 (56%), 53 (32%) and 5 (3%) of these indicated moderate [visual analogue scale (VAS)>or=30 mm], severe (VAS>54 mm) and worst possible pain (VAS=100 mm), respectively. On multivariate analyses, pre-existing pain (OR=2.60 95% CI 1.26-5.36), anxiety about the diagnostic outcome of BMA (OR=3.17 95% CI 1.54-6.52), anxiety about needle-insertion (OR=2.49 95% CI 1.22-5.10) and low employment status (sick-leave/unemployed) (OR=3.14 95% CI 1.31-7.55) were independently associated with an increased risk of pain during BMA. At follow-up 10 min after BMA, 40/235 (17%) patients reported pain. At 1, 3, 6 and 7 days post BMA, pain was present in 137 (64%), 90 (42%), 43 (20%) and 25 (12%) patients, respectively. CONCLUSIONS: We found that 3/4 of hematologic patients who underwent BMA reported procedural pain; one third of these patients indicated severe pain. Pre-existing pain, anxiety about the diagnostic outcome of BMA or needle-insertion, and low employment status were independent risk factors.

Reducing uncertainty in health-care resource allocation.

A key task for health policymakers is to optimise the outcome of health care interventions. The pricing of a new generation of cancer drugs, in combination with limited health care resources, has highlighted the need for improved methodology to estimate outcomes of different treatment options. Here we introduce new general methodology, which for the first time employs continuous hazard functions for analysis of survival data. Access to continuous hazard functions allows more precise estimations of survival outcomes for different treatment options. We illustrate the methodology by calculating outcomes for adjuvant treatment of gastrointestinal stromal tumours with imatinib mesylate, which selectively inhibits the activity of a cancer-causing enzyme and is a hallmark representative for the new generation of cancer drugs. The calculations reveal that optimal drug pricing can generate all win situations that improve drug availability to patients, make the most of public expenditure on drugs and increase pharmaceutical company gross profits. The use of continuous hazard functions for analysis of survival data may reduce uncertainty in health care resource allocation, and the methodology can be used for drug price negotiations and to investigate health care intervention thresholds. Health policy makers, pharmaceutical industry, reimbursement authorities and insurance companies, as well as clinicians and patient organisations, should find the methodology useful.

Adjuvant imatinib treatment improves recurrence-free survival in patients with high-risk gastrointestinal stromal tumours (GIST).

Palliative imatinib treatment has dramatically improved survival in patients with malignant gastrointestinal stromal tumours, particularly in patients with tumours harbouring activating KIT mutations. To evaluate the effectiveness of adjuvant imatinib after radical surgery, a consecutive series of patients with high-risk tumours (n=23) was compared with historic controls (n=48) who were treated with surgery alone. The mean follow-up period was over 3 years in both groups. Only 1 out of 23 patients (4%) in the adjuvant treatment group developed recurrent disease compared to 32 out of 48 patients (67%) in the control group. This preliminary study indicates that 1 year of adjuvant treatment with imatinib dramatically improves recurrence-free survival. Confirmation of these findings awaits the results of ongoing randomised studies.

Nutritional aspects in patients with functional gastrointestinal disorders and motor dysfunction in the gut. Working team report of the Swedish Motility Group (SMoG).

In reviews regarding the management of patients with functional gastrointestinal disorders and motility disturbances within the gut nutritional aspects and dietary advice is often put forward as being of great importance. However, there are relatively few high-quality, interventional studies in the literature supporting an important role for general dietary advice to improve symptoms in these patients. Nutritional supplementation to patients with malnutrition due to severe dysfunction of the gastrointestinal tract is of course less controversial, even though different views on how this should be performed exist. The content of this article is based on presentations given by the authors during the second meeting of the Swedish Motility Group held in Gothenburg in March 2005, and aims to give an overview on the role of dietary advice and nutritional supplementation to patients with gastrointestinal dysfunction of different severity.

Effects of long-term treatment with oxytocin in chronic constipation; a double blind, placebo-controlled pilot trial.

BACKGROUND: Oxytocin and its receptor have been found throughout the gastrointestinal (GI) tract, where it affects gut function. Clinically, we have noticed an improvement of bowel habits during lactation in constipated women. The aim of this study was to examine whether oxytocin has an effect on bowel symptoms and psychological well being in women with refractory constipation. METHODS: Fifty-nine women with refractory constipation were included in a double blind, multicentre study. After a 2-week run-in period, they were randomly allocated to nasal inhalation of either placebo or oxytocin treatment twice daily for 13 weeks, followed by a 2 weeks, posttreatment period. The patients completed a questionnaire every day concerning bowel habits, abdominal pain and discomfort, and Gastrointestinal Symptoms Rating Scale (GSRS) and Psychological General Well-being (PGWB) twice during the study; namely, during the baseline period and at the end of the treatment period. RESULTS: Both oxytocin and placebo led to improvement of the constipation according to the GSRS and led to improvement in the sensation of incomplete evacuation and anorectal obstruction, without significant differences between the groups. Abdominal pain and discomfort responded weakly to oxytocin, with no effect of the placebo. In a subgroup of patients with IBS and concomitant depression, a weak improvement in depressed mood was observed after oxytocin administartion. CONCLUSION: Nasal administration of oxytocin had no significant advantage over placebo concerning an effect on constipation. However, it seems to have a positive effect on abdominal pain and discomfort and depressed mood. These findings should be further explored.

Plasma motilin in untreated celiac disease.

Celiac disease (CD) is characterized by mucosal villous atrophy mostly confined to the proximal small intestine. Upper-gut motor abnormalities have been reported. Motilin, localized in cells in the proximal small intestine, is a trigger factor for the migrating motor complex. Plasma levels of motilin were studied in 16 untreated CD patients and in an age-matched control group of 18 healthy subjects by radioimmunoassay and by high-performance liquid chromatography (HPLC). The fasting levels of motilin and postprandial levels were significantly higher in CD patients compared to controls (P<0.01) and HPLC revealed a divergent individual pattern of the motilin fragments.

Systemic adenosine infusion reduces the area of tactile allodynia in neuropathic pain following peripheral nerve injury: a multi-centre, placebo-controlled study.

Systemic adenosine has been shown in earlier case reports and a small placebo-controlled study to reduce pathological sensory dysfunction such as tactile allodynia in neuropathic pain. To evaluate this further, the effects of systemic adenosine infusion (50 microg/kg/min for 60 min) on tactile sensory dysfunction and pain was evaluated in 26 patients suffering peripheral neuropathic pain characterized by dynamic tactile allodynia. A randomized, cross-over, double-blind, placebo-controlled technique was used in this multi-centre study. Psychophysical methods were used to evaluate sensory dysfunction and spontaneous pain. The area of dynamic tactile allodynia was significantly reduced by adenosine compared with placebo (p=0.043), but spontaneous pain and tactile pain threshold were not significantly improved compared with the effects of placebo treatment. As a secondary outcome, a higher incidence of positive subjective effects on the clinical pain condition, in a few cases with long duration (several months), following adenosine treatment was found when the global effect of respective treatment was assessed (p=0.028). The results demonstrate involvement of adenosine receptor-sensitive pain mechanisms in some aspects of the sensory dysfunction often found in neuropathic pain.

Neuropeptides in the duodenal mucosa of chronic alcoholic heavy drinkers.

Previous studies have shown that patients with chronic alcohol ingestion may show a variety of morphological and functional alterations in the small intestine. In this study, we have focused on the neuroendocrine system in the duodenal mucosa in chronic alcoholics; an area little studied. Twenty-three defined chronic alcoholics admitted to the hospital for detoxification underwent clinical examination, followed by upper gastrointestinal endoscopy and blood tests on average 4 days after the most recent alcohol intake. Biopsy specimens were taken from the distal part of the descending duodenum for both immunohistochemical and routine histological examination. The control group consisted of 25 patients referred for upper endoscopy mainly because of dyspepsia (ulcer, reflux type), but who were otherwise healthy. A normal carbohydrate-deficient transferrin and a history of low alcohol consumption (<40 g/week) were required for inclusion in the control group. The tissue specimens were studied using antisera for the following neuropeptides: cholecystokinin, galanin, gastric inhibitory peptide (GIP), glucagon, motilin, neuropeptide Y, pituitary adenylyl cyclase activating peptide, secretin, serotonin, somatostatin, substance P, vasoactive intestinal polypeptide and protein gene product, as a general marker for neurones and cells of the diffuse neuroendocrine system. The density of nerve fibres was evaluated semi-quantitatively and the number of endocrine cells per unit length of mucosa was counted in sections cut perpendicularly to the mucosal surface. All the different peptidergic nerve fibres in the alcohol group showed higher densities than the corresponding controls. However, this was not a statistically significant difference. A slightly significant increase (P = 0.02) in the numbers of glucagon and GIP cells was seen in the alcohol group. Gastrointestinal symptoms were frequently present (87%) in chronic alcoholics. We suggest that chronic alcohol consumption in man may have a general effect on the peptidergic nerve system and some endocrine cell types in the duodenal mucosa.

Alpha1-antitrypsin deficiency may be a risk factor for duodenal ulcer in patients with Helicobacter pylori infection.

BACKGROUND: Most individuals with Helicobacter pylori infection in Western countries have no evidence of peptic ulcer disease (PUD). We therefore assessed the PiZ deficiency variant of the major plasma protease inhibitor alpha1-antitrypsin (alpha1AT) as a risk factor for PUD in H. pylori-infected individuals. METHODS: The cohort comprised 100 patients with endoscopically or surgically proven PUD (30 patients with duodenal ulcer (DU) and 70 patients with gastric ulcer (GU)) and 162 age- and sex-matched controls with PUD-negative endoscopic findings and no history of PUD. Plasma samples were screened for alpha1AT deficiency (PiZ) with an enzyme-linked immunosorbent assay (ELISA) and phenotyped by isoelectric focusing. H. pylori infection was evaluated with an IgG ELISA technique. RESULTS: Among the 262 patients 17 (6.5%) were positive for the PiZ alpha1AT deficiency, a frequency of the same magnitude as in the Swedish general population (4.7%). Of the PiZ carriers 76% (13 of 17) had H. pylori antibodies compared with 61% (151 of 245) of the non-PiZ carriers (NS). The prevalence of DU tended to be higher in H. pylori-positive PiZ carriers than in non-PiZ carriers (15.4%, 4 of 26 versus 0 of 4). Furthermore, among patients with DU a high PiZ allele frequency (13.3%, 4 of 30) was found compared with the general population (4.7%) (odds ratio (OR), 3.2; 95% confidence interval (CI), 1.09-8.94; P = 0.02). All DU patients carrying the PiZ allele were positive for H. pylori. In addition, four of five PiZ carriers with H. pylori infection and PUD had DU. CONCLUSIONS: The PiZ allele may be a contributing factor in the development of DU in H. pylori-positive individuals.

Adenosine reduces secondary hyperalgesia in two human models of cutaneous inflammatory pain.

UNLABELLED: Secondary hyperalgesia is characterized by increased sensitivity to noxious mechanical stimuli in the area surrounding injured skin. The pathophysiological mechanisms involve increased excitability of second-order neurons located in the spinal cord, i.e., central sensitization. The mechanisms behind this phenomenon may be of importance in clinical pain, including neuropathic pain. To study the effects of systemic infusion of the endogenous compound adenosine (ADO) on sensory function, a superficial cutaneous burn injury was induced by the 4-min topical application of mustard oil or by heat (47 degrees C for 7 min) during i.v. ADO infusion (60 microg x kg(-1) x min(-1)). Healthy human subjects (n = 10 for each model) were tested, using a blinded, placebo-controlled procedure. The area of secondary hyperalgesia, as well as tactile and thermal sensory function, was tested using psychophysical methods during and after treatments. ADO significantly reduced the area of secondary hyperalgesia in both models. The maximal reduction compared with placebo was 58% +/- 20% (heat burn) and 39% +/- 13% (mustard oil burn). No other differences in sensory function were observed. The results are interpreted as an ADO-induced modulatory effect on the mechanisms of central sensitization. IMPLICATIONS: We tested the effects of adenosine on the development of increased sensitivity in the skin surrounding a superficial skin injury in humans. A superficial skin bum was induced with a chemical irritant or heat. The results show that adenosine reduces the skin area with increased sensitivity surrounding the injury.

Intrathecal administration of the adenosine A1 receptor agonist R-phenylisopropyl adenosine reduces presumed pain behaviour in a rat model of central pain.

Effects of intrathecally (i.t.) administered R-phenylisopropyl adenosine (R-PIA), an adenosine A1 receptor agonist, on presumed pain behaviour were assessed in a rat model of chronic central pain. Spinal cord injury was induced photochemically via laser irradiation of the spinal cord after intravenous injection of erythrosin B in rats. The chronic allodynia-like behaviour that developed in some animals was studied. R-PIA (3 and 10 nmol), injected i.t. reduced the mechanical and cold allodynia-like symptoms as tested with von Frey filaments and ethyl-chloride spray, respectively. No side effects were observed. The effect of R-PIA was significant for up to 5 h and was reversed by theophylline, an adenosine receptor antagonist.

Neuropeptides in idiopathic chronic constipation (slow transit constipation).

Tissue specimens from the large bowel of 18 patients with long-standing slow transit constipation were investigated to determine the distribution and density of several neuropeptides and amines in the enteric nerve system, and also of endocrine cells in comparison to normal individuals. CGRP (calcitonin gene-related peptide), galanin, glucagon, GRP (gastrin-releasing peptide), metenkephalin, motilin, neuropeptide Y (NPY), PACAP, peptide YY (PYY), serotonin, somatostatin, substance P and VIP were studied by immunohistochemistry. Tissue concentrations of VIP, substance P and galanin were also measured by radioimmunoassay. Significantly increased VIP, SP and galanin contents were found in specimens from the ascending colon. Levels of VIP and galanin were also increased in the transverse colon. Immunohistochemistry revealed only marginal changes with an increased density of PACAP nerve fibres in the smooth muscle and of VIP and PACAP nerves in the myenteric plexus of the transverse colon. In the descending colon substance P and NPY immunoreactivity were also increased in the myenteric plexus while the density of VIP nerve fibres was reduced in the mucosa/submucosa. The frequency of PYY-containing cells and the 5-HT-containing cells in the ascending colon was significantly increased in the constipated patients.

Intrathecal adenosine analog administration reduces substance P in cerebrospinal fluid along with behavioral effects that suggest antinociception in rats.

UNLABELLED: Adenosine and adenosine analogs induce analgesia in humans and presumed antinociception in animal models when administered both systemically and intrathecally. In the present investigation in rats, we studied the effects of intrathecally administered adenosine analogs, with or without systemic coadministration of an adenosine antagonist (theophylline), on substance P (SP) and calcitonin gene-related peptide (CGRP) concentrations in cerebrospinal fluid (CSF). In parallel, nociceptive reflex testing (tail immersion latency) and motor function were evaluated. The potent unselective adenosine receptor agonist N-ethylcarboxamide-adenosine (NECA) and the relatively adenosine A1 receptor selective agonist R-phenyl-isopropyl-adenosine (R-PIA) both reduced SP-like immunoreactivity (-LI) by 50%, whereas CGRP-LI remained unchanged. There was a dose-dependent increase in tail immersion latency. This effect was present without motor impairment when R-PIA was administered in doses up to 5 nmol. R-PIA (10-100 nmol), as well as 1-100 nmol of the unselective agonist NECA, produced dose-dependent motor impairment. The reduction of SP-LI as well as the behavioral effects were reversed by theophylline. We conclude that SP reduction in CSF, which possibly reflects reduced SP turnover after adenosine receptor stimulation, provides an additional possible mechanism of action for the analgesic effects of adenosine. IMPLICATIONS: We studied the interactions between the known pain mediator substance P and substances with effects similar to the endogenous pain modulator adenosine in rats. The results suggest that the pain-reducing effect of adenosine is, at least partly, due to a reduction of substance P in cerebrospinal fluid.

Disturbed motilin and cholecystokinin release in the irritable bowel syndrome.

BACKGROUND: The irritable bowel syndrome (IBS) is associated with motor abnormalities in the small intestine and colon. Neuropeptides may have an important role in initiating and regulating the intestinal motility. Motilin has been proposed to initiate the peristaltic reflex in the small intestine and cholecystokinin the gastrocolic reflex. METHODS: In 18 patients with IBS and 11 healthy control subjects plasma motilin and cholecystokinin (CCK) concentrations were measured after intraluminal stimulation of water and a fat-rich meal. RESULTS: The IBS patients had reduced motilin secretion after both water intake and the fat meal. In contrast, the fat meal elicited an exaggerated and prolonged CCK release in the IBS patients. CONCLUSIONS: Disturbed motilin and CCK release may partly be responsible for the intestinal dysmotility in the IBS patients.