Bakgrund: Cancersmärta är ett växande problem för både vårdpersonal och patienter, eftersom cancer drabbar allt fler människor. Tidigare forskning visar att sjuksköterskor uttrycker en brist på kunskap och insikt i cancersmärta och patienters erfarenheter av cancersmärta, särskilt i eget hem. Syfte: Syftet med denna studie är att beskriva patienters upplevelser av cancersmärta i hemmet. Metod: En kvalitativ litteraturstudie, som inkluderar 13 artiklar analyserade utifrån Evans beskrivande syntes med en berättande sammanfattning. Resultat: Resultatet från den här studien består av tre huvudteman och sex subteman. Huvudteman inkluderar Upplevelser av att förlora kontroll, Upplevelser av oförståelse och Upplevelser av självstyre av smärtvården. Slutsats: Patienterna upplevde att cancersmärtan resulterade i en förlust av kontroll eftersom de upplevde att smärtan begränsade deras liv samt att vara hjälplös. De upplevde en oförståelse vilket omfattade att ha svårt att tala om och förstå smärtan. De uttryckte upplevelser av självstyre i smärtvården både genom att på egna sätt hantera och uthärda smärtan och att vara den som kontrollerar smärtbehandlingen. / Background: Cancer pain is a growing problem for both our personal and patients, where cancer affects more and more people. Previous research shows that nurses express a lack of knowledge and insight into cancer pain and patients' experiences of cancer pain, especially in their own homes. Aim: The aim of this study is to describe patients' experiences of cancer pain at home. Method: A qualitative literature study, using 13 articles analyzed based on Evans' description, appeared with a narrative summary. Results: The results of this study consist of three main themes and six sub-themes. Main themes include experiences of losing control, experiences of lack of understanding and experiences of autonomy in pain-care. Conclusion: The patients experienced that the cancer pain resulted in a loss of control when they experienced limitations of their lives, as well as a life of helplessness. They experienced a lack of understanding of their pain which included having difficulties in talking about and understanding the pain. They expressed experiences of autonomy in their pain-care by managing and enduring their pain in their own ways as well as being in control of their pain treatment.

Pain is a common symptom in cancer patients, restricts daily life activities and reduces survival time. Identification of sociodemographic, medical and psychological correlates of pain among cancer patients in Germany could help identify subgroups most in need of pain management. In this multicenter, epidemiologic cross-sectional study, we assessed pain prevalence and severity, quality of life (QoL) and psychological distress in a sample of 3,745 cancer patients across all tumor entities. In total, 37.9% patients suffered from cancer-related pain and 56.1% suffered from non-specific pain. Younger, female, less educated and unemployed patients reported pain more frequently and more severe pain (p < 0.001). Pain was associated with distress, depression, anxiety, QoL, tumor stage (p < 0.001), and time since diagnosis (p = 0.012). Pain assessment and pain management should be a routine part of cancer treatment and cancer survivorship care plans.

Metastatic bone cancers cause severe symptoms including pain that compromises patient functional status, quality of life, and survival. Current treatment strategies have limited efficacy and dose-limiting side effects. Cancer-induced bone pain (CIBP) is a unique pain state that shares features with but is distinct from the pathology of neuropathic and inflammatory pain. This dissertation investigates how CIBP is generated and maintained by the direct effects of cancer cells on their metastatic microenvironment and the peripheral nervous system, including unique signaling properties and gene expression changes. In particular, we found that genetic knockdown of the functional subunit xCT of the system xC- cystine/glutamate antiporter can reduce CIBP, further elucidating this as a therapeutic of interest. We found that the neuroprotective voltage-gated calcium channel inhibitors progesterone and pregabalin markedly reduce mechanical hypersensitivity and excitability in sensory neurons of the dorsal root ganglion (DRG) in male rat models of neuropathic pain, but that these effects and less pronounced in females. In cancer pain, these sex differences are reversed, with females but not males demonstrating a delay in time-to-onset of mechanical hypersensitivity. We also analyzed gene expression at the DRG by RNA-Sequencing of rat models of CIBP. Our findings uncovered differential gene expression between CIBP and sham controls and between ipsilateral and contralateral DRGs in CIBP model rats. These studies have identified several promising avenues for therapeutic research for CIBP. / Dissertation / Doctor of Philosophy (PhD) / The tools we have right now to manage severe and chronic pain are insufficient. Patients with advanced cancers including bone cancer can suffer from very severe pain. This pain is generated in a number of ways including by the tumour itself releasing chemicals that activate pain-sensing nerves, by the destruction of the bone in and around the tumour, and by the sensitization of the nervous system, which can make pain worse and longer lasting. We have taken three approaches to researching cancer pain and to investigating new treatments. We have found that by reducing the amount of glutamate that cancer cells can release into their environment, we can reduce cancer pain in mice. We also found that treating rats with pregabalin and progesterone can change nerve signaling and reduce neuropathic pain, but that this effect is most pronounced in male rats with neuopathic pain and smaller in female rats with neuropathic pain, and even smaller in rats with cancer pain. We also analyzed expression of all the protein-coding genes in dorsal root ganglia from rats with cancer pain and found that there are many differences from rats without pain. Some of these differences may be promising new research targets. Going forward this research has provided important evidence necessary for next steps to develop new therapies and research strategies for cancer pain.

Neurólises de plexos simpáticos têm sido utilizadas no tratamento da dor oncológica, mostrando ser um recurso terapêutico bastante eficaz e seguro. Alguns estudos apontam a utilização da neurólise de plexos simpáticos em estágios iniciais da doença por prevenir a dor e melhorar a qualidade de vida, contrariando a OMS que preconiza o uso de métodos invasivos em última instância. Em estudo prospectivo, randomizado e controlado, neurólise de plexos simpáticos realizada em estágios diferentes do tratamento da dor oncológica foi comparada com o tratamento farmacológico. Foram selecionados 60 pacientes com câncer abdominal ou pélvico e alocados em três grupos. No grupo I (precoce) os pacientes estavam em uso de AINEs e opióides fracos ou fortes (dose inferior a 90mg/dia de morfina) e reportavam dor (VAS &#61619; 4) quando foram submetidos a neurólise plexo celíaco (NPC), neurólise do plexo hipogástrico superior (NPHS) ou neurólise plexo simpático lombar (NPSL) de acordo com o sítio de dor. No grupo II (tardio) a neurólise foi realizada quando a utilização de AINEs e morfina foram iguais ou superiores a 90mg/dia de morfina e VAS>4. No grupo III (controle) os pacientes fizeram uso somente de medicação analgésica. Os pacientes foram observados durante 8 semanas e avaliados quanto à intensidade da dor (VAS), consumo de opióides e qualidade de vida. Imediatamente após as neurólises e durante todo o tempo de observação, os pacientes dos grupos precoce e tardio apresentaram redução da intensidade da dor e do consumo de opióides, além disso melhora da qualidade de vida quando comparados com o grupo controle. Não houve diferenças entre os grupos precoce e tardio nestes aspectos. Efeitos adversos correlacionados com o uso de opióide, como náuseas e/ou vômitos, perda do apetite e constipação foram significativamente maiores no grupo controle. Complicações relacionadas às neurólises, tais como hipotensão e diarréia, foram transitórias e não deferiram significativamente do grupo controle. Não foram encontradas complicações sérias em nenhum dos grupos experimentais. A neurólise de plexos simpáticos foi efetiva na redução da intensidade da dor e do consumo de analgésicos e dos efeitos adversos relacionados com a administração de drogas, e na melhora da qualidade de vida dos pacientes. Embora não havendo diferenças entre os grupos precoce e tardio, os resultados apontam a necessidade de utilizar esta técnica como recurso não somente em fase terminal da doença. / Neurolytic sympathetic plexus blocks (NSPB) have been used as a quite effective and safe therapeutic resource for the treatment of cancer pain. Studies point to the use of NSPB in the early phases of the disease to prevent pain and to improve the life quality, contradicting WHO that extols the use of invasive methods ultimately. We compared the use of neurolytic plexus block in two different phases of the treatment of oncology pain with the pharmacological therapy. In prospective study, randomized and controlled, sixty patients with abdominal or pelvic oncology pain were allocated to tree groups. In group I (early block) the patients using NSAID and weak opioid or oral morphine at a dose of less than 90 mg/day and reporting pain (VAS &#61619; 4) were submitted to a neurolytic celiac plexus block (NCPB), superior hypogastric plexus block (SHPB) or lumbar sympathetic ganglionic chain (LSGCB), in accordance to the site of pain. In group 2 (late block) the patients were submitted neurolysis when using NSAID and oral morphine at a dose equals to or more than 90 mg/day and VAS &#61619; 4. In group 3 (control), patients were treated with pharmacological therapy only. The patients were observed for 8 weeks and appraised for the intensity of the pain (VAS), opioid consumption and quality of live. The patients of groups I and II had reduction of the intensity of the pain, opioid consumption and get better quality of live immediately after to the neurolytic and during the whole time of observation when compared with the group control. There were no significant differences between groups I and II with these aspects. Adverse effects correlated with the use of opioids, as nauseas and/or vomits, loss of the appetite and constipation were significantly larger in the group control. Neurolysis related complications such as hypotension and diarrhea, were transitory and statistically similar to these found in the control group. They were not found serious complications. The neurolysis of sympathetic plexus was shown to be effective to reduce the intensity of pain, analgesic consumption and adverse effects related to the use of opioids, and in the improvement of the quality of life. The results point to the usefulness of indicating neurolytic procedure for the management of cancer pain not only in terminal phase of the disease.

Neurólises de plexos simpáticos têm sido utilizadas no tratamento da dor oncológica, mostrando ser um recurso terapêutico bastante eficaz e seguro. Alguns estudos apontam a utilização da neurólise de plexos simpáticos em estágios iniciais da doença por prevenir a dor e melhorar a qualidade de vida, contrariando a OMS que preconiza o uso de métodos invasivos em última instância. Em estudo prospectivo, randomizado e controlado, neurólise de plexos simpáticos realizada em estágios diferentes do tratamento da dor oncológica foi comparada com o tratamento farmacológico. Foram selecionados 60 pacientes com câncer abdominal ou pélvico e alocados em três grupos. No grupo I (precoce) os pacientes estavam em uso de AINEs e opióides fracos ou fortes (dose inferior a 90mg/dia de morfina) e reportavam dor (VAS &#61619; 4) quando foram submetidos a neurólise plexo celíaco (NPC), neurólise do plexo hipogástrico superior (NPHS) ou neurólise plexo simpático lombar (NPSL) de acordo com o sítio de dor. No grupo II (tardio) a neurólise foi realizada quando a utilização de AINEs e morfina foram iguais ou superiores a 90mg/dia de morfina e VAS>4. No grupo III (controle) os pacientes fizeram uso somente de medicação analgésica. Os pacientes foram observados durante 8 semanas e avaliados quanto à intensidade da dor (VAS), consumo de opióides e qualidade de vida. Imediatamente após as neurólises e durante todo o tempo de observação, os pacientes dos grupos precoce e tardio apresentaram redução da intensidade da dor e do consumo de opióides, além disso melhora da qualidade de vida quando comparados com o grupo controle. Não houve diferenças entre os grupos precoce e tardio nestes aspectos. Efeitos adversos correlacionados com o uso de opióide, como náuseas e/ou vômitos, perda do apetite e constipação foram significativamente maiores no grupo controle. Complicações relacionadas às neurólises, tais como hipotensão e diarréia, foram transitórias e não deferiram significativamente do grupo controle. Não foram encontradas complicações sérias em nenhum dos grupos experimentais. A neurólise de plexos simpáticos foi efetiva na redução da intensidade da dor e do consumo de analgésicos e dos efeitos adversos relacionados com a administração de drogas, e na melhora da qualidade de vida dos pacientes. Embora não havendo diferenças entre os grupos precoce e tardio, os resultados apontam a necessidade de utilizar esta técnica como recurso não somente em fase terminal da doença. / Neurolytic sympathetic plexus blocks (NSPB) have been used as a quite effective and safe therapeutic resource for the treatment of cancer pain. Studies point to the use of NSPB in the early phases of the disease to prevent pain and to improve the life quality, contradicting WHO that extols the use of invasive methods ultimately. We compared the use of neurolytic plexus block in two different phases of the treatment of oncology pain with the pharmacological therapy. In prospective study, randomized and controlled, sixty patients with abdominal or pelvic oncology pain were allocated to tree groups. In group I (early block) the patients using NSAID and weak opioid or oral morphine at a dose of less than 90 mg/day and reporting pain (VAS &#61619; 4) were submitted to a neurolytic celiac plexus block (NCPB), superior hypogastric plexus block (SHPB) or lumbar sympathetic ganglionic chain (LSGCB), in accordance to the site of pain. In group 2 (late block) the patients were submitted neurolysis when using NSAID and oral morphine at a dose equals to or more than 90 mg/day and VAS &#61619; 4. In group 3 (control), patients were treated with pharmacological therapy only. The patients were observed for 8 weeks and appraised for the intensity of the pain (VAS), opioid consumption and quality of live. The patients of groups I and II had reduction of the intensity of the pain, opioid consumption and get better quality of live immediately after to the neurolytic and during the whole time of observation when compared with the group control. There were no significant differences between groups I and II with these aspects. Adverse effects correlated with the use of opioids, as nauseas and/or vomits, loss of the appetite and constipation were significantly larger in the group control. Neurolysis related complications such as hypotension and diarrhea, were transitory and statistically similar to these found in the control group. They were not found serious complications. The neurolysis of sympathetic plexus was shown to be effective to reduce the intensity of pain, analgesic consumption and adverse effects related to the use of opioids, and in the improvement of the quality of life. The results point to the usefulness of indicating neurolytic procedure for the management of cancer pain not only in terminal phase of the disease.

Background: Pain related to cancer is the biggest problem for patients with this diagnosis. Every year, many suffering cancer patients die without adequate pain relief. Although, there are international guidelines from the World Health Organization (WHO) for pain relief in cancer-related pain, they are not followed in all countries, leading to global inequality. Aim: The aim of the study was to shed light on patients' experiences of cancer-related pain and its pain-relief from a global perspective. Method: A general literature study was conducted using content analysis of 12 scientific articles including both qualitative and quantitative research methodology. Results: During the content analysis, four main categories emerged: “Quality of life”, “Caregiver - Patient”, “Knowledge” and “Socio-economic factors”. Among the factors that affect pain-relief, access to medicines, information, knowledge, fear of side effects and addiction, patients' cultural and religious background have the greatest impact. Conclusion: A large difference in access to medicines and care is demonstrated around the world, which makes a difference in patients' experiences. There is a need for guidelines on pain-relief in cancer-related pain and continuous information about them at a local level. In addition, all countries are required to adhere to and follow international guidelines to improve cancer-related pain-relief, which can reduce inequality in care and suffering around the world. / Bakgrund: Smärta relaterad till cancer är det största problemet för patienter med denna diagnos. Varje år dör många lidande cancerpatienter utan en adekvat smärtlindring. Trots att det finnsmediinternationella riktlinjer från World Health Organisation (WHO) för smärtlindring vid cancerrelaterad smärta följs inte de i alla länder vilket leder till den globalaojämlikheten. Syfte: Syftet med studien var att belysa patientersupplevelser av cancerrelaterad smärta och dess smärtlindring ur det globala perspektivet. Metod: En allmän litteraturstudie genomfördes med hjälp av innehållsanalys av 12 vetenskapliga artiklarinnefattande bådekvalitativ ochkvantitativ forskningsmetodik. Resultat: Under innehållsanalys framkom det fyra huvudkategorier: “Livskvalitet”, “Vårdgivare -Patient”, “Kunskap” och “Socioekonomiska faktorer”. Bland faktorer som påverkar smärtlindring hartillgång till läkemedel, information, kunskap, rädsla för biverkningar och beroende, patienters kulturella samt religiösa bakgrundden största inverkan. Slutsats: Stor skillnad på tillgång till läkemedel och vård påvisas runt om i världenvilket ger skillnad på patienters upplevelser. Det föreligger behov av riktlinjer om smärtlindring vid cancerrelaterad smärta och kontinuerlig information om dem på lokal nivå. Dessutom krävs det att alla länder ska förhålla sig och följa de internationella riktlinjerna för att förbättra cancerrelaterad smärtlindring vilket kan minska ojämlikhet i vården och lidandet runt om i världen.

Bakgrund: Avancerad smärta är något som uppstår vid svår cancersjukdom, vilket leder till en begräsning hos patienterna. I dessa fall är det viktigt som sjuksköterska att noga analysera smärtan och administrera bästa möjliga smärtlindring, då det ska leda till en god död och patienten ska slippa lidande. Syfte: Syftet är att beskriva sjuksköterskors upplevelser av svårlindrad cancersmärta vid cancersjukdom och palliativ vård. Metod: En beskrivande litteraturstudie som baserar sig på 9 vetenskapliga artiklar som sökts via pubmed. Data analyserades med tematisk analys. Huvudresultat: Resultatet i denna litteraturstudie beskriver hur sjuksköterskors upplevelser var att inte alltid kunna bota smärta vid cancersjukdom och i palliativ vård. De komponenter som framkom var sjuksköterskans upplevelser av genombrottssmärta där sjuksköterskorna beskrev att det var brist på läkemedel samt att återhållen smärtbehandling var återkommande. Sjuksköterskorna beskrev rädsla över att ge läkemedel samt att utbildning i palliativ vård och smärtlindring var viktigt för att kunna ge en rättvis vård. Sjuksköterskorna upplevde också organisationen som hinder samt att personalbrist och okunskap ger onödigt lidande. Slutsats: Avancerad cancersmärta finns i hela världen, vilket medför ytterligare kunskaper och utbildning för att hjälpa patienter i sitt lidande vid smärta i palliativ vård. Smärta ska inte behandlas olika beroende på var de bor, därav behövs riktlinjer för att utföra en likasinnad vård för alla runt om i världen som lever med cancersjukdom. / Background: Advanced pain is something that occurs in severe cancer, which leads to a limitation in patients. In these cases, it is important as a nurse to carefully analyze the pain and administer the best possible pain relief, as it should lead to a good death and the patient should avoid suffering. Aim: The purpose is to describe nurses' experiences of difficult-to-alleviate cancer pain in cancer disease and palliative care. Method: A descriptive literature study based on 9 scientific articles applied for via PubMed. Data were analyzed with thematic analysis. Main results: The results of this literature study describe how nurses' experiences were not always able to cure pain in cancer and in palliative care. The components that emerged were the nurse's experiences of breakthrough pain, where the nurses described that there was a shortage of medicines, and that restrained pain treatment was recurring. The nurses described fear of giving medicines and that training in palliative care and pain relief was important in order to be able to provide fair care. The nurses also experienced the organization as an obstacle and that staff shortages and ignorance cause unnecessary suffering. Conclusion: Advanced cancer pain is found all over the world, which brings additional knowledge and education to help patients in their suffering of end-of-life pain. Pain should not be treated differently depending on where they live, hence guidelines are needed to perform a similar care for everyone around the world who lives with cancer.

La douleur chronique non-cancéreuse (DCNC) est un problème de santé qui touche environ une personne sur cinq au Canada. Elle est associée à une dégradation de la qualité de vie physique et mentale et occasionne des coûts économiques importants. Pour lutter contre la DCNC, les opioïdes ont été largement recommandés et prescrits malgré l’absence de preuves de leur efficacité à long terme, entraînant une augmentation des surdoses. Ces surdoses mais surtout celles causées par le fentanyl illicite ont fait naître une crise sanitaire, la crise des opioïdes. Pour juguler cette crise, des lignes directrices ont été émises pour encadrer de façon plus stricte la prescription d’opioïdes pour la DCNC. Cependant ces mesures peuvent constituer des barrières d’accès aux traitements pour les personnes vivant avec de la DCNC. Il est donc important de garantir un accès sécuritaire aux opioïdes à ceux qui en ont besoin pour fonctionner tout en limitant l’accès inapproprié qui alimente la crise des opioïdes. L’objectif de cette thèse était d’identifier les personnes susceptibles de bénéficier d’une utilisation efficace et sécuritaire des opioïdes à long terme et de mieux comprendre la douleur et les difficultés d’accès au traitement chez les personnes utilisatrices de drogues (PUD). Une première étude, visant à identifier les prédicteurs de l’efficacité des opioïdes à long terme, n’a pas permis de faire ressortir des caractéristiques des personnes susceptibles d’en bénéficier. Deux autres études ont permis d’étudier le nomadisme médical (doctor shopping), un indicateur d’utilisation problématique d’opioïdes, qui consiste à obtenir des ordonnances qui se chevauchent de plusieurs médecins et à les faire dispenser dans différentes pharmacies. Les résultats ont montré que cette pratique est rare chez les personnes vivant avec de la DCNC mais qu’elle peut être associée à la survenue de surdose. Les caractéristiques des personnes à risque de faire du nomadisme médical ont été identifiées permettant ainsi un meilleur suivi. Enfin, une dernière étude a montré que la DCNC est très fréquente chez les PUD et qu’une proportion importante de cette population a recours à des drogues illicites pour soulager leur douleur, courant ainsi le risque de faire une surdose. Ces études montrent la nécessité d’une médecine personnalisée tenant compte des caractéristiques et situations individuelles afin de prescrire le bon médicament à la bonne personne. En somme, ces résultats ont permis d’accroître les connaissances scientifiques sur l’utilisation des opioïdes pour la DCNC. / Chronic non-cancer pain (CNCP) is a health problem that affects about one in five people in Canada. CNCP is associated with a deterioration of physical and mental health-related quality of life and incurs significant economic costs. To better manage CNCP, opioids have been widely recommended and prescribed despite the lack of evidence on their long-term effectiveness, leading to an increase in opioid overdoses. These overdoses but mainly those caused by illicit fentanyl have led to the opioid crisis. To address this crisis, guidelines have been issued to tighten the prescribing of opioids for CNCP. However, these measures can exacerbate barriers of access to treatment for people living with CNCP. Therefore, it is important to ensure safe access to opioids for those who need this medication to improve function while reducing inappropriate access that contributes to the opioid crisis. The aim of this thesis was to identify the characteristics of patients who may benefit from effective and safe long-term opioid therapy and to better understand pain and treatment access difficulties among people who use drugs (PWUD). An initial study, which aimed at examining predictors of long-term opioid efficacy, failed to identify characteristics of those likely to benefit from opioid therapy. Two other studies investigated doctor shopping, an indicator of problematic opioid use, which consists of obtaining overlapping prescriptions from several doctors and pharmacies. The results showed that this practice is rare among people living with CNCP but may be associated with the occurrence of opioid overdose. The characteristics of people at high-risk to engage in opioid doctor shopping were identified, thus allowing better monitoring. Finally, a last study showed that CNCP is very frequent among PWUD and that a significant proportion of this population uses illicit drugs to relieve their pain, which can increase the risk of overdose. These studies show the need for personalized medicine considering individual characteristics and specific situations to prescribe the right drug to the right person. In summary, these results have increased the scientific knowledge about the long-term opioid use in CNCP.

No / The United Kingdom is considered to be the world leader in nurse prescribing, no other country having the same extended non-medical prescribing rights. Arguably, this growth has outpaced research to evaluate the benefits, particularly in areas of clinical practice where patients have complex co-morbid conditions such as palliative care. This is the first study of non-medical prescribing in palliative care in almost a decade. AIM: To explore the current position of nurse prescribing in palliative care and establish the impact on practice of the 2012 legislative changes. DESIGN: An online survey circulated during May and June 2013. PARTICIPANTS: Nurse members (n = 37) of a regional cancer network palliative care group (61% response rate). RESULTS: While this survey found non-medical prescribers have embraced the 2012 legislative changes and prescribe a wide range of drugs for cancer pain, we also identified scope to improve the transition from qualified to active non-medical prescriber by reducing the time interval between the two. CONCLUSION: To maximise the economic and clinical benefit of non-medical prescribing, the delay between qualifying as a prescriber and becoming an active prescriber needs to be reduced. Nurses who may be considering training to be a non-medical prescriber may be encouraged by the provision of adequate study leave and support to cover clinical work. Further research should explore the patients' perspective of non-medical prescribing.

Contexte: La douleur chronique non cancéreuse (DCNC) génère des retombées économiques et sociétales importantes. L’identification des patients à risque élevé d’être de grands utilisateurs de soins de santé pourrait être d’une grande utilité; en améliorant leur prise en charge, il serait éventuellement possible de réduire leurs coûts de soins de santé. Objectif: Identifier les facteurs prédictifs bio-psycho-sociaux des grands utilisateurs de soins de santé chez les patients souffrant de DCNC et suivis en soins de première ligne. Méthodologie: Des patients souffrant d’une DCNC modérée à sévère depuis au moins six mois et bénéficiant une ordonnance valide d’un analgésique par un médecin de famille ont été recrutés dans des pharmacies communautaires du territoire du Réseau universitaire intégré de santé (RUIS), de l’Université de Montréal entre Mai 2009 et Janvier 2010. Ce dernier est composé des six régions suivantes : Mauricie et centre du Québec, Laval, Montréal, Laurentides, Lanaudière et Montérégie. Les caractéristiques bio-psycho-sociales des participants ont été documentées à l’aide d’un questionnaire écrit et d’une entrevue téléphonique au moment du recrutement. Les coûts directs de santé ont été estimés à partir des soins et des services de santé reçus au cours de l’année précédant et suivant le recrutement et identifiés à partir de la base de données de la Régie d’Assurance maladie du Québec, RAMQ (assureur publique de la province du Québec). Ces coûts incluaient ceux des hospitalisations reliées à la douleur, des visites à l’urgence, des soins ambulatoires et de la médication prescrite pour le traitement de la douleur et la gestion des effets secondaires des analgésiques. Les grands utilisateurs des soins de santé ont été définis comme étant ceux faisant partie du quartile le plus élevé de coûts directs annuels en soins de santé dans l’année suivant le recrutement. Des modèles de régression logistique multivariés et le critère d’information d’Akaike ont permis d’identifier les facteurs prédictifs des coûts directs élevés en soins de santé. Résultats: Le coût direct annuel médian en soins de santé chez les grands utilisateurs de soins de santé (63 patients) était de 7 627 CAD et de 1 554 CAD pour les utilisateurs réguliers (188 patients). Le modèle prédictif final du risque d’être un grand utilisateur de soins de santé incluait la douleur localisée au niveau des membres inférieurs (OR = 3,03; 95% CI: 1,20 - 7,65), la réduction de la capacité fonctionnelle liée à la douleur (OR = 1,24; 95% CI: 1,03 - 1,48) et les coûts directs en soins de santé dans l’année précédente (OR = 17,67; 95% CI: 7,90 - 39,48). Les variables «sexe», «comorbidité», «dépression» et «attitude envers la guérison médicale» étaient également retenues dans le modèle prédictif final. Conclusion: Les patients souffrant d’une DCNC au niveau des membres inférieurs et présentant une détérioration de la capacité fonctionnelle liée à la douleur comptent parmi ceux les plus susceptibles d’être de grands utilisateurs de soins et de services. Le coût direct en soins de santé dans l’année précédente était également un facteur prédictif important. Améliorer la prise en charge chez cette catégorie de patients pourrait influencer favorablement leur état de santé et par conséquent les coûts assumés par le système de santé. / Background: Chronic non-cancer pain (CNCP) has major social and economic impacts. Identifying patients at risk of being heavy health care users could be very useful; therefore, by improving their care direct health care costs could eventually be reduced. Purpose: To identify bio-psycho-social factors predicting the risk of being a heavy health care user among primary care CNCP patients. Methods: Patients reporting moderate to severe CNCP for at least 6 months with an active analgesic prescription from a primary care physician were recruited in community pharmacies on the territory of the Réseau universitaire integré de santé (RUIS), of the Université de Montréal between May 2009 and January 2010. The latter comprises six areas: Mauricie and centre du Quebec, Laval, Montreal, the Laurentians, Lanaudière and Montérégie. Upon recruitment, their bio-psycho-social characteristics were documented through self-administered and telephone questionnaires. The direct health costs were estimated for the health care services provided to patients in the year preceding and following recruitment using the database of the Régie d’Assurance maladie du Québec, RAMQ (Quebec province public health care insurance). These costs took into account the pain-related hospitalizations, emergency room visits, ambulatory care, and medication prescribed for pain treatment and drug side effects Heavy health care users were defined as those in the highest annual direct health care costs quartile in the year following recruitment. Logistic multivariate regression models using the Akaike information criterion were developed in order to identify the predictors of heavy health care use. Results: The median annual direct health care cost incurred by heavy health care users (n = 63) was CAD 7,627, compared to CAD 1,554 for the standard health care users (n = 188). The final predictive model of the risks of being a heavy health care user included pain located in the lower body (Odds ratio (OR) = 3.03; 95% CI: 1.20 - 7.65), pain-related disability (OR = 1.24; 95% CI: 1.03 - 1.48), and health care costs in the previous year (OR = 17.67; 95% CI: 7.90 - 39.48). Other retained variables were sex, comorbidity, depression level, and patients’ attitudes towards medical pain cure. Conclusion: Patients suffering from CNCP in the lower body and having a greater impact of pain on their daily functioning were more likely to be heavy health care and services users. Previous year annual direct cost was also a significant predictor. Improving pain management in this clientele of patients may improve their health and eventually reduce their health care cost to the health care system.