MAURIVAX: A Vaccination Campaign Project in a Hospital Environment for Patients Affected by Autoimmune Diseases and Adult Primary Immunodeficiencies.

Background: Patients with autoimmune diseases (ADs) and primary immunodeficiencies (PIDs) are characterized by an increased risk of noninvasive and widespread infections as they are considered frail patients. In addition, many flares of the underlying disease are reported after routine vaccinations. To date, the vaccination rate in these two populations is suboptimal. According to the latest guidelines, targeted interventions are needed, such as strengthening the network of vaccination activities. Our project aimed to propose a pilot network for carrying out the recommended vaccinations in frail patients. Methods: The Allergy and Immunology Center of the Mauriziano Hospital in Turin, Italy started the "Maurivax" project, a facilitated pathway for frail patients to administer the recommended vaccinations in the setting of a dedicated structure where they could be properly followed up. Results: From June 2022 to February 2023, 49 patients underwent a vaccination consultation: 45 of them (91.8%) were subsequently vaccinated. Among these, 36 subjects (80%) were affected by an active AD and were already in treatment with immunosuppressive therapy or about to start it. Seven patients (15.5%) had a confirmed diagnosis of PID or showed a clinical presentation that was highly suggestive of that condition. Overall, twenty-seven patients (60%) showed a high-grade immunosuppression and six (13.3%) had a low-grade immunosuppression. No patients had a disease flare within 30 days from vaccination and no severe reactions after vaccination was observed. Conclusions: Adherence and vaccination safety at our immunology hospital vaccine clinic dedicated to patients with ADs and PIDs were high. We propose an effective model for managing vaccinations in frail patients in a specialist hospital setting.

COPD, but Not Asthma, Is Associated with Worse Outcomes in COVID-19: Real-Life Data from Four Main Centers in Northwest Italy.

Introduction: Asthma, along with inhaled steroids, was initially considered a risk factor for worse clinical outcomes in COVID-19. This was related to the higher morbidity observed in asthma patients during previous viral outbreaks. This retrospective study aimed at evaluating the prevalence of asthma among patients admitted due to SARS-CoV-2 infection as well as the impact of inhaled therapies on their outcomes. Furthermore, a comparison between patients with asthma, COPD and the general population was made. Methods: All COVID-19 inpatients were recruited between February and July 2020 from four large hospitals in Northwest Italy. Data concerning medical history, the Charlson Comorbidity Index (CCI) and the hospital stay, including length, drugs and COVID-19 complications (respiratory failure, lung involvement, and the need for respiratory support) were collected, as well as the type of discharge. Results: patients with asthma required high-flow oxygen therapy (33.3 vs. 14.3%, p = 0.001) and invasive mechanical ventilation (17.9 vs. 9.5%, p = 0.048) more frequently when compared to the general population, but no other difference was observed. Moreover, asthma patients were generally younger than patients with COPD (59.2 vs. 76.8 years, p < 0.001), they showed both a lower mortality rate (15.4 vs. 39.4%, p < 0.001) and a lower CCI (3.4 vs. 6.2, p < 0.001). Patients with asthma in regular therapy with ICS at home had significantly shorter hospital stay compared to those with no treatments (25.2 vs. 11.3 days, p = 0.024). Discussion: Our study showed that asthma is not associated with worse outcomes of COVID-19, despite the higher need for respiratory support compared with the general population, while the use of ICS allowed for a shorter hospital stay. In addition, the comparison of asthma with COPD patients confirmed the greater frailty of the latter, according to their multiple comorbidities.

Autoantibodies and Rheumatologic Manifestations in Hepatitis C Virus Infection.

HCV is a virus that can cause chronic infection which can result in a systemic disease that may include many rheumatologic manifestations such as arthritis, myalgia, sicca syndrome, cryoglobulinemia vasculitis as well as other non-rheumatological disorders (renal failure, onco-haematological malignancies). In this population, the high frequency of rheumatoid factor (45-70%), antinuclear (10-40%) and anticardiolipin (15-20%) antibodies is a B-cell mediated finding sustained by the infection. However, the possibility that a primitive rheumatic pathology may coexist with the HCV infection is not to be excluded thus complicating a differential diagnosis between primitive and HCV-related disorders.

Intestinal microbiota changes induced by TNF-inhibitors in IBD-related spondyloarthritis.

BACKGROUND: The close relationship between joints and gut inflammation has long been known and several data suggest that dysbiosis could link spondyloarthritis (SpA) to inflammatory bowel diseases (IBD). The introduction of biological drugs, in particular tumour necrosis factor inhibitors (TNFi), revolutionised the management of both these diseases. While the impact of conventional drugs on gut microbiota is well known, poor data are available about TNFi. AIM: To investigate the impact of TNFi on gut microbiota. METHODS: We evaluated 20 patients affected by enteropathic arthritis, naïve for biological drugs, treated with TNFi at baseline and after 6 months of therapy. All patients followed a Mediterranean diet. Patients performed self-sampling of a faecal sample at baseline and after 6 months of therapy. NGS-based ITS and 16S rRNA gene sequencing was performed, followed by the taxonomic bioinformatics analysis. RESULTS: After 6 months of therapy, we detected a remarkable increase in Lachnospiraceae family (Δ +10.3, p=0.04) and Coprococcus genus (Δ +2.8, p=0.003). We also noted a decreasing trend in Proteobacteria (Δ -8.0, p=0.095) and Gammaproteobacteria (Δ -9, p=0.093) and an increasing trend in Clostridia (Δ +8.2, p=0.083). We did not find differences between TNFi responders (SpA improvement or IBD remission achieved) and non-responders in terms of alpha and beta diversity. CONCLUSIONS: Our findings are consistent with the hypothesis that TNFi therapy tends to restore the intestinal eubiosis.

Efficacy of a fixed combination of palmitoylethanolamide and acetyl-l-carnitine (PEA+ALC FC) in the treatment of neuropathies secondary to rheumatic diseases.

BACKGROUND: The neurologic complications of rheumatic diseases (RDs) are highly variable, and their manifestations are linked to the pathogenesis and clinical phenotype of the specific RDs. In rheumatoid arthritis, for example, the peripheral nervous system is most commonly involved and mononeuritis multiplex, nerve entrapment and vasculitic sensorimotor neuropathies are not uncommon. Often the therapy for these disorders is not easy and is characterized by the use of different drugs. Palmitoylethanolamide (PEA) has been tested in a wide variety of animal models and has been evaluated in several clinical studies for nerve compression syndromes, demonstrating that PEA acts as an effective and safe analgesic compound. Acetyl-L-Carnitine (ALC) has also been shown to be an effective and safe treatment in painful peripheral neuropathy. In the last years the synergistic effect between PEA and ALC has been demonstrated. The aim of our study was to evaluate the efficacy of supplementation of standard therapy (STh) with Kalanit® (Chiesi Italia Spa; Parma, Italy) in patients with peripheral neuropathy secondary to RDs. METHODS: Patients at the time of enrollment were affected by RDs with neuropathy from <12 months, documented by electromyography. The analyzed patients were treated with the STh chosen according to their rheumatic disease (RA or SpA) and for their neuropathy (e.g. analgesic, NSAIDs, pregabalin or gabapentin) as per clinical practice. The sample was divided into 2 groups: group 1, patients treated with STh, to which a fixed combination of PEA (600 mg) + ALC (500 mg) (Kalanit®) was added twice a day for 2 weeks and then once a day for 6 months; group 2, patients treated only with STh. Each patient underwent clinical evaluations and questionnaires were administered in order to evaluate their neuropathy and the efficacy of the therapy. RESULTS: In group 1, 18 patients suffering from sciatic pain, 16 patients from carpal tunnel syndrome and 8 patients with peripheral neuropathy of the lower limbs were included and PEA + ALC FC was added to STh. These patients were compared with patients from group 2, who had the same pathology and demographic characteristics: 20 patients with sciatic pain, 15 with carpal tunnel syndrome and 5 with peripheral neuropathy of the lower limbs, respectively; this group was treated with STh only. Patients treated with PEA + ALC FC had a significant improvement in pain VAS compared to patients treated with group 2 in all the diseases analyzed (P value: sciatic pain 0.032, carpal tunnel syndrome 0.025 and lower limbs neuropathy 0.041). Patients in group 1 showed a significant improvement compared to patients treated in group 2 also from a specific score. Specifically, LBP-IQ showed significant improvement in group one (P value: 0.031), as did CHFD (P=0.011) and NPQ (P=0.025). CONCLUSIONS: The synergistic effect of PEA and ALC seems to have a further advantage in the treatment of this type of pathology, including the anti-inflammatory effect but also in terms of therapy optimization and therefore of better adherence to treatments. Our study shows that it is important to identify the type of pain to follow an accurate diagnostic algorithm, considering the clinical characteristics of the patient and carefully evaluate the indication, preferring a multimodal approach.

Prevalence of hepatitis B virus infection and risk of reactivation in rheumatic population undergoing biological therapy.

OBJECTIVES: Hepatitis B (HBV) is a common comorbidity among rheumatic patients. The prevalence of HBV infection and the rate of reactivation remain unclear. The literature data suggested a higher risk in chronic than in past infection. Currently, the literature data are mostly focused on anti-TNF and rituximab. This retrospective observational study aimed to analyse the prevalence of HBV infection and the risk of viral reactivation in a population of rheumatic patients undergoing anti-TNF and non-anti-TNF agents. METHODS: We analysed 1216 rheumatic patients, treated with both csDMARDs and bDMARDs between 2006 and 2017. Serologic markers for HBV (HBsAg, anti-HBs, anti-HBc) were performed prior and during biologic treatment. Patients with chronic or resolved infection were monitored every 3 months. RESULTS: The prevalence of HBV in our cohort was 15.7% (chronic infection: 0.4%, resolved infection: 12.6%, anti-HBc positivity alone: 2.6%). 12 (6.2%) out of 191 HBV infected patients experienced a reactivation. All of them showed markers of past infection. One patient experienced HBV reactivation despite lamivudine. Only one patient experienced acute hepatitis, probably due to the interruption of immunosuppressors in anticipation of surgery, not preceded by any HBV prophylactic treatment. CONCLUSIONS: HBV reactivation is a rare event in patients treated with a bDMARD and it can also occur while taking lamivudine, not only in chronic carriers (as per the literature data) but also in inactive ones. Regular screening followed by prompt treatment can prevent symptoms or complications. Due to the risk of hepatitis following the immune reconstitution, an antiviral therapy should be considered in the case of sudden discontinuation of csDMARDs or bDMARD.

Rheumatic manifestations in inflammatory bowel disease.

Rheumatic manifestations are the most frequent extra-intestinal manifestations (EIMs) in inflammatory bowel disease (IBD) patients, and they are responsible for a relevant reduction of quality of life. IBD is associated with a variety of musculoskeletal manifestations such as arthritis and non-inflammatory pain as well as with metabolic diseases, such as osteoporosis. Different imaging techniques (primarily ultrasound, magnetic resonance imaging and X-rays) can help the clinician to correctly identify the nature of manifestations and to treat the patient accordingly. Nowadays, in the setting of IBD-related arthritides, different drugs are available and can be effective on both articular and intestinal involvement. Therefore, a multi-disciplinary approach provides an early diagnosis and a better clinical outcome that can only be given from the recognition and consideration of the different EIMs. As for rheumatic manifestations, namely IBD-related arthritis, an early intervention allows to control disease activity and to prevent structural damage.

Rheumatologic manifestations of hepatitis C in the era of direct-acting antiviral agents.

Beyond the classic hepatic complications, hepatitis C (HCV) infection is considered as a systemic disease, since extrahepatic manifestations become clinically evident in 40% to 70% of the patients and it can frequently include rheumatic ones. Furthermore, HCV can promote the production of several autoantibodies, thus complicating the differential diagnosis between primitive and HCV-related rheumatic disorders. The recent development of direct-acting antivirals (DAA) against HCV has revolutionized the field, reducing the damage stemming from systemic inflammatory phenomena and persistent immune activation associated with continuous HCV replication. Our review focuses on the main rheumatologic manifestations associated with chronic HCV infection as well as the impact of DAA interferon-free treatments on such extrahepatic clinical involvement.

The clinical presentation in adulthood of juvenile idiopathic arthritis.

Juvenile idiopathic arthritis (JIA) is a chronic systemic inflammatory disease, which affects children and adolescents, characterized by significant differences when compared to inflammatory rheumatisms in adulthood. Today, in a panorama enriched in the last decades with great improvements in the diagnostic and therapeutic field, a far from negligible portion and an increasing number of patients with JIA require the continuation of treatments in adulthood. This specific population of patients, given the high incidence of extra-articular manifestations, residual irreversible disabilities, comorbidities related to an inflammatory process and extended immunosuppressive treatments during the age of development, requires precise attentions in the follow-up and a multidisciplinary approach characterized by different clinical, psychological and social aspects.

Ultrasound-guided intra-articular injection: efficacy of hyaluronic acid compared to glucocorticoid in the treatment of knee osteoarthritis.

BACKGROUND: Osteoarthritis (OA) is a degenerative joint disease which causes pain and functional impairment in adults over 50 years old with consequent important disability. Unfortunately, there is no definitive cure for OA, thus the approach is characterized by multiple treatments that can manage its symptoms. Even though data from randomized controlled trials and meta-analyses indicate that intra-articular hyaluronic acid (IAHA) offers the best benefit/risk balance among the various pharmacologic treatments to improve OA-related knee pain, there is a lack of agreement among national and international guidelines about such uses of IAHA for the medical management of symptomatic knee OA. To minimize confounding factors and biases, the aim of our study was to evaluate the efficacy of the different weight and concentration of IAHA treatment in patients suffering from knee OA comparing to glucocorticoids (GC) joint injections. Furthermore, to make the procedure more accurate and assessment more objective, we use ultrasonography (US) with power Doppler (PWD) to help us differentiate between active and inactive inflammation within joints and periarticular soft tissues. METHODS: We performed a retrospective evaluation of a cohort of patients with knee OA, diagnosed according to the ACR criteria, treated by US-guided joint injection of HA and GC. The patients were catalogued according to the type of treatment they underwent: group A, patients treated with HA (1.5%) >1500 kDa (three US-guided knee injections one week apart); group B, patients treated with HA (2%) 800-1200 kDa (three US-guided knee injections one week apart); group C, patients treated with glucocorticoids (three US-guided knee injections of triamcinolone acetate 40 mg one week apart). All patients were monitored for 6 months, evaluating: subjective pain using a 10-cm Visual Analogue Scale; pain, stiffness, and functionality using the Western Ontario and McMaster Universities Arthritis Index (WOMAC); the concomitant intake of anti-inflammatory and/or analgesic drugs through a questionnaire; and US results by grey scale and PWD. RESULTS: A total of 171 patients affected by knee OA were evaluated (women 72.3%) with a mean age of 69.3±4.1 years. All the subjects analyzed showed a pain reduction at 6 months after treatment (group A: -39.5; group B: -36.9; group C: -30.8). The difference between the three groups was statistically significant (Kruskall-Wallis P=0.001) and in particular between group A and group C (P=0.000) and between group B and group C (P=0.005), but not between A and B (P=0.258). WOMAC was statistically significantly improved from baseline in all groups examined (group A: -11.9; group B: -14.9; group C: -11.2). The PWD score showed a statistically significant improvement in group B (-0.64) even after 6 months (P=0.004). All patients in the different groups showed a statistically significant reduction of concomitant therapy compared to baseline with respect to paracetamol and non-steroidal anti-inflammatory drugs (NSAIDs)/COX2 therapy, while only group B showed a statistically significant reduction for opioids. CONCLUSIONS: This study demonstrated the efficacy of OA treatment with medium molecular weight HA in favor of the higher concentration of HA that may affect the reduction of pro-inflammatory mediators. Furthermore, US monitoring allowed to evaluate aspects related to synovial involvement, which cannot be appreciated with standard imaging.

Epidemiology and liver transplantation burden of primary biliary cholangitis: a retrospective cohort study.

BACKGROUND: There is a wealth of data documenting the epidemiology of primary biliary cholangitis (PBC) globally; however, the epidemiology of PBC has not been as well studied in Canada. Our study characterized the Canadian prevalence of PBC and the number of liver transplantations because of PBC. METHODS: For this retrospective cohort study we used national hospital administrative records from the Canadian Institute for Health Information, with the exception of Quebec for the prevalence estimate and Quebec and British Columbia for the transplant analysis. Prevalent patients were identified through a diagnostic code for PBC of the Canadian version of the 10th revision of the International Classification of Diseases. PBC transplant patients were identified from their transplant record. Descriptive statistics were used to summarize the characteristics of the study cohorts. RESULTS: In 2015, 8680 patients with PBC were identified in Canada, translating to a prevalence of 318 cases per million. Annual prevalence by province varied, ranging from 283 (95% confidence interval [CI] 269-297) cases per million to 465 (95% CI 426-504) cases per million, and the 6-year PBC liver transplantation rate ranged from 3.17 (95% CI 1.27-6.54) to 5.92 (95% CI 3.71-9.08) per million. The Atlantic provinces exhibited the highest PBC prevalence and close to the highest 6-year liver transplantation rate (465 [95% CI 426-504] cases per million and 5.70 [95% CI 426-504, 3.19-9.56] cases per million, respectively). We observed the lowest PBC prevalence (283 [95% CI 269-297] cases per million) and the second lowest 6-year liver transplantation rate in Ontario (3.37 [95% CI 2.47-4.50] cases per million). INTERPRETATION: The prevalence of PBC that we found in Canada is similar to the prevalence reported in other studies, but our work also indicates geographic variation within this country. Given our finding of geographic clustering of PBC across Canada, we hypothesize that environmental and genetic factors contribute to the pathogenesis of this condition.

Severe, eosinophilic asthma in primary care in Canada: a longitudinal study of the clinical burden and economic impact based on linked electronic medical record data.

BACKGROUND: Stratification of patients with severe asthma by blood eosinophil counts predicts responders to anti-interleukin (IL)-5 (mepolizumab and reslizumab) and anti-IL-5 receptor α (benralizumab) therapies. This study characterized patients with severe asthma who could qualify for these biologics in a primary care setting. METHODS: We retrospectively selected patients from July 1, 2010, to June 30, 2014, using a linked electronic medical records (EMR) database (IMS Evidence 360 EMR Canada) for > 950,000 patients in primary care in Ontario, Canada. Patients aged ≥ 12 years with ≥ 2 documented asthma diagnoses were identified as having severe asthma based on prescriptions for high-dosage inhaled corticosteroids (ICS) plus either a leukotriene receptor antagonist, long-acting ß2-agonist (LABA), or theophylline filled on the same day. Patients' asthma was considered severe also if they received a prescription for ICS with oral corticosteroids (OCS) or an additional prescription for omalizumab. Patient characteristics, asthma-related medications, and blood eosinophil counts were captured using observed care patterns for the year prior to ICS/LABA and/or OCS prescription. Health care resource use (HCRU) and costs were captured throughout the 1-year follow-up period. RESULTS: We identified 212 patients who met the criteria for severe asthma. These patients required an average of 6.5 physician visits during the 1-year follow-up period (95% confidence interval 5.7-7.3), and 20 (9%) were referred to respiratory specialists. Overall, 56 patients (26%) with severe asthma had complete blood counts, of whom 23 (41%) had blood eosinophil counts ≥ 300 cells/µL and might be considered for anti-eosinophil therapies. Patients with severe asthma and blood eosinophil counts ≥ 300 cells/µL had more respiratory specialist referrals (17% vs. 12%) than patients with blood eosinophils < 300 cells/µL. CONCLUSIONS: Our data suggest that during 2010-2014, Ontario primary care patients with severe asthma and high blood eosinophil counts had greater HRCU than those with lower counts. Approximately 41% of patients with severe asthma could qualify for anti-eosinophil drugs based on blood eosinophil counts. However, the eosinophilic status of most patients was unknown. It is appropriate to increase awareness of the use of blood eosinophil counts to identify patients who could be considered for anti-eosinophil therapies.

Identifying Psoriasis and Psoriatic Arthritis Patients in Retrospective Databases When Diagnosis Codes Are Not Available: A Validation Study Comparing Medication/Prescriber Visit-Based Algorithms with Diagnosis Codes.

BACKGROUND: Using diagnosis code-based algorithms is the primary method of identifying patient cohorts for retrospective studies; nevertheless, many databases lack reliable diagnosis code information. OBJECTIVES: To develop precise algorithms based on medication claims/prescriber visits (MCs/PVs) to identify psoriasis (PsO) patients and psoriatic patients with arthritic conditions (PsO-AC), a proxy for psoriatic arthritis, in Canadian databases lacking diagnosis codes. METHODS: Algorithms were developed using medications with narrow indication profiles in combination with prescriber specialty to define PsO and PsO-AC. For a 3-year study period from July 1, 2009, algorithms were validated using the PharMetrics Plus database, which contains both adjudicated medication claims and diagnosis codes. Positive predictive value (PPV), negative predictive value (NPV), sensitivity, and specificity of the developed algorithms were assessed using diagnosis code as the reference standard. Chosen algorithms were then applied to Canadian drug databases to profile the algorithm-identified PsO and PsO-AC cohorts. RESULTS: In the selected database, 183,328 patients were identified for validation. The highest PPVs for PsO (85%) and PsO-AC (65%) occurred when a predictive algorithm of two or more MCs/PVs was compared with the reference standard of one or more diagnosis codes. NPV and specificity were high (99%-100%), whereas sensitivity was low (≤30%). Reducing the number of MCs/PVs or increasing diagnosis claims decreased the algorithms' PPVs. CONCLUSIONS: We have developed an MC/PV-based algorithm to identify PsO patients with a high degree of accuracy, but accuracy for PsO-AC requires further investigation. Such methods allow researchers to conduct retrospective studies in databases in which diagnosis codes are absent.

Serological and clinical profile of systemic sclerosis: analysis in a cohort of patients from a single center in Northern Italy.

BACKGROUND: The purpose of this study was to identify the frequency of autoantibodies among patients affected by systemic sclerosis (SSc) in our Rheumatology Center and analyze the correlation between serological and clinical presentations. METHODS: An automated fluoro-enzyme-immunoassay is used for the qualitative detection of sixteen antibodies: anti-dsDNA, antiRo52, antiRo60, antiSS-B, antiTopoisomerasi-I, antiCENP-B, anti-fibrillarin, antiMi-2, anti-Sm, antiU1sn-RNP, antiRNP70, antiPm/Scl100, antiPCNA, antiJo-1, antiRibosomal-P, antiRNA-Polymerase-III. These parameters were further correlated with clinical presentation of the disease. RESULTS: One-hundred and six patients who fulfilled the ACR classification criteria of SSc have been screened. Similarly to the findings of other studies, a strong association between anti-Centromere antibodies and clinical indicators of better prognosis has been showed; conversely, the anti-Scl70 antibodies are associated with diffuse SSc and higher severity. Some antibodies (antiR052, antiU1RNP) are correlated with a diagnosis of autoimmune overlap. A protective effect of AntiCentromere regarding pulmonary fibrosis and skin ulcers has been shown (P<0.05). The presence of AntiScl70 correlated with cardiac involvement (arrhythmias, pericarditis and myocarditis) and the Anti-U1RNP correlated with the presence of skin ulcers. CONCLUSIONS: The diagnostic importance of SSc antibodies against a variety of nuclear and cytoplasmic antigens has become increasingly recognized, as confirmed by the inclusion into 2013American College of Rheumatology (ACR)/the European League Against Rheumatism clinical classification criteria for SSc. A number of studies reported variable geographic rates of antibody prevalence in SSc, which may be related to either genetic or environmental factors. However, the association of specific antibodies with clinical manifestations continues to be claimed. New testing methods which include a wider spectrum of detectable antibodies may support the daily rheumatological and dermatological clinical practice in defining clinical subsets of disease and provide prognostic information.

Abatacept and granulocyte-colony stimulating factor in a patient with rheumatoid arthritis and neutropenia.

Neutropenia in patients with inflammatory diseases increases the risk of infection due to the disease itself and the related immunosuppressive treatments. We report the case of a 54-year-old female with rheumatoid arthritis and following development of chronic neutropenia. All investigations excluded pathogenic relations with drugs and/or other clinical situations; the gravity of neutropenia required a treatment with G-CSF and the increased articular inflammatory activity justified a biologic-therapy, abatacept (CTLA4 inhibitors). The juxtaposition of immunostimulants and immunosuppressors led to great effectiveness for both hematological and rheumatic issues. To date, while some biologic drugs (TNF, IL6R and CD20 inhibitors) have reported relations with neutropenia, no such relevance subsists for Abatacept. Our case reports the experience of the safe effective use of abatacept and G-CSF for 8 years.

The Direct Economic Burden of Gout in an Elderly Canadian Population.

OBJECTIVE: To estimate the direct healthcare cost and resource use from the public payer perspective between patients with incident gout and matched gout-free patients in Ontario. METHODS: Patients with incident gout aged ≥ 66 with uninterrupted Ontario Health Insurance Plan (OHIP) coverage in the 1-year baseline period were included in the study. Patients with gout were indexed at first gout diagnosis or prescription over the study period April 1, 2008, to March 31, 2014. Gout-free patients with no gout diagnosis within history were matched (up to 5:1) to each patient with gout. Linked medical records were analyzed until end of study, death, or OHIP ineligibility. Bang and Tsiatis adjusted healthcare costs and resource use were compared using bootstrap p-values and 95% CI. RESULTS: A total of 29,894 patients with gout and 148,231 gout-free patients were included in the study. Patients were 56% male, had a median Adjusted Clinical Group healthcare resource use band of moderate morbidity, and had a median age of 75-79 years. Baseline comorbidities were similar between groups except for renal disease. Analyzing 5-year total healthcare costs, patients with gout ($44,297) incurred a significantly higher average healthcare cost compared to gout-free patients ($33,965), for an incremental cost of $10,332 (95% CI $9617-$11,039; p < 0.01). Similar trends were observed in all individual healthcare component cost and use metrics. CONCLUSION: Following onset of gout, patients in Ontario incur significantly greater healthcare costs and resource use compared to matched gout-free patients. Alternative gout management strategies should be investigated to reduce the incremental burden of gout borne by the Ontario healthcare system.