Associations between metabolic factors and radiographic knee osteoarthritis in early disease - a cross-sectional study of individuals with knee pain

Objective

Metabolic factors have been shown to be associated to severe radiographic knee osteoarthritis (RKOA). However, more knowledge is needed in early clinical knee osteoarthritis (KOA). The aim was to study associations between metabolic factors and radiographic knee osteoarthritis (OA) in individuals with knee pain. A second aim was to study associations between metabolic factors and RKOA in those with normal BMI and in those overweight/obese, respectively.

Method

This cross-sectional study included 282 individuals with knee pain (without cruciate ligament injury) and aged 30–67 years, and 70% women. Waist circumference, body mass index (BMI), proportion of fat and visceral fat area (VFA) were assessed. RKOA was defined as Ahlbäck grade 1 in at least one knee. Fasting blood samples were taken and triglycerides, cholesterol (total, low density lipoprotein (LDL) and high density lipoprotein (HDL)), C-reactive protein (CRP), glucose, HbA1C were analysed. Metabolic syndrome was defined in accordance with the International Diabetes Federation (IDF). Associations were analysed by logistic regression.

Results

Individuals with RKOA were older, had higher BMI, higher VFA, larger waist circumference and had increased total cholesterol, triglycerides and LDL-cholesterol, but not fasting glucose. There was no difference between the group with RKOA vs. non-radiographic group regarding the presence of metabolic syndrome. In a subgroup analysis of individuals with normal BMI (n = 126), those with RKOA had higher VFA, more central obesity, higher levels of CRP and total cholesterol, compared with individuals without RKOA. In individuals with obesity, age was the only outcome associated to RKOA.

Conclusion

There were clear associations between metabolic factors and RKOA in individuals with knee pain, also in those with normal BMI. In individuals with obesity age was the only variable associated to RKOA.

Trial registration:

clinicalTrials.gov Identifier: NCT04928170.

POS0951 SERUM PROTEIN RESPONSE TO A SINGLE HIGH-INTENSITY INTERVAL TRAINING BOUT – COMPARISON BETWEEN INDIVIDUALS WITH SPONDYLOARTHRITIS AND HEALTHY CONTROLS

Background

Axial spondyloarthritis (axSpA) is a chronic inflammatory disease affecting mainly the axial skeleton. To decrease the risk of cardiovascular comorbidity, aerobic training is recommended as a part of disease management in patients with axSpA. High-intensity interval training (HIIT) interventions are, in addition to other recommended treatments, believed to positively affect the disease activity (1). However, the knowledge about the acute effects of HIIT on the inflammatory process at the molecular level is less studied. Understanding the acute HIIT effects on cytokines and additional serum proteins in axSpA is important for further long-term HIIT interventions and recording of the effect of HIIT on the axSpA disease profile.

Objectives

To study the acute effects on serum proteins, such as cytokines, myokines, and inflammatory- and bone-related proteins, in response to a single bout of HIIT, and to compare the levels between baseline and post-HIIT in patients with axSpA and healthy controls (HC).

Methods

The pilot study included twenty-one participants (10 female, 11 male), mean (SD) age 40 (7) years, ten with axSpA, and eleven age and sex matched HC, who performed a single HIIT on a cycle ergometer consisting of 4x4 minutes interval (90% heart rate, HR-max) with three minutes active rest in between (70% of HR-max). Disease activity (BASDAI, 0-10) in patients with axSpA was 1.6 (0.8). Health status EuroQol (EQ5D, 0-1) were 0.87 (0.11) for axSpA, and 0.93 (0.10) for HC. The groups were well matched with no difference in baseline data for weight, BMI, EQ5D, blood pressure or aerobic capacity.

Blood samples were taken before (baseline) and one hour after the single HIIT. The following serum proteins were analyzed on a Luminex MAGPIX System (Luminex corporation, Austin, TX USA): Interleukin (IL)-6, IL-17, IL-18, TNFαAGPIX System (Luminex corporatiosteoprotegerin, osteocalcin, osteopontin, and FGF-23. A three-way analysis of variance (ANOVA) was used to detect differences between groups, between sexes, and before and after a HIIT bout in a 2(group)*2(sex)*2(time) design. For main effects or interactions significant at p≤0.05, simple effect t-tests were used to determine the specific effects.

Results

A group main effect (p=0.048) showed that the serum level of IL-6 was increased one hour after the HIIT session primarily in the HC, 0.4 pg/ml (SD±0.4) at baseline vs. post-HIIT 1.8 (2.0). The concentration of the cytokines/chemokine IL-17, IL-18, TNFα group main effect (p=0.048) showed that the serum level of IL-6 was increased one hour after the HIIT session primarily in30) in VEGF-A showed that the axSpA group had significantly lower VEGF-A at baseline, 159 pg/ml (138) vs 326 (184) in the control group (which might be due to anti-inflammatory medication). A sex main effect (p=0.029) was observed from baseline to post-HIIT for the bone hormone osteocalcin, with a more pronounced decrease of serum osteocalcin in women with axSpA, 14.0 ng/ml (8.3) vs. post HIIT 13.2 (6.9). Moreover, the level of the multifunctional protein osteopontin was significantly lower (sex main effect, p=0.021) in women, 10.7 ng/ml (7.0) vs. men 20.4 (10.1), post-HIIT.

Conclusion

This pilot study shows that one bout of HIIT influences the expression of proteins involved in inflammation and metabolism, and that sex is an important factor in the response to HIIT. The results should be followed up in longer intervention studies including higher numbers of participants.

References

[1]Sveaas, S. H. et al. (2019). High intensity exercise for 3 months reduces disease activity in axial spondyloarthritis (axSpA): a multicentre randomised trial of 100 patients. British journal of sports medicine, 54(5), 292-297.

Disclosure of Interests

Åsa Andersson: None declared, Emma Haglund Consultant of: Novartis, Emma Berthold: None declared, Elisabeth Mogard Consultant of: Novartis, Anna Torell: None declared, M Charlotte Olsson: None declared

POS1527-HPR HEALTH PROMOTION IN INDIVIDUALS WITH KNEE PAIN – DIFFERENT WAYS TO ENABLE AND MAINTAIN A BALANCE IN EVERYDAY LIFE BASED ON THE ABILITIES

Background

Most individuals with knee pain develop radiographic knee osteoarthritis over time [1], and up to 30% develop chronic widespread pain (CWP) [2]. Many studies only focus on physical activity or weight loss when it comes to managing knee osteoarthritis (KOA) and chronic pain. There is a challenge to get more individuals to follow the existing recommendations for KOA, including physical activity and weight loss [3]. However, the interaction between the various physical, mental, and social factors regarding health promotion is complex. More research is needed to understand health-promoting activities applied amongst individuals with knee pain.

Objectives

To explore health-promoting activities in individuals with knee pain.

Methods

The study was a part of the Halland Osteoarthritis cohort (ClinicalTrials.gov NCT04928170), including 306 individuals with knee pain without earlier diagnosed KOA, cruciate ligament injury or other rheumatological disorder. A purposeful sample of 22 individuals (13 women, 9 men; median age 52 years) participated in the study. Ten had radiographic KOA, 12 had chronic regional pain, 9 reported CWP, 16 were overweight, and 13 met the WHO recommendations for physical activity with moderate intensity. Semi-structured interviews were conducted and followed a pilot-tested interview guide initiated with open-ended questions such as “What do you do to maintain your health?” and “What enables you to keep health?”. The interviewers followed the participants reasoning, and to obtain depth in the data, the participant received follow-up questions such as “Please, can you tell me more about…?”. The interviews were audio-recorded and transcribed verbatim. Data analysis was performed by latent qualitative content analysis and revealed an overall theme including two categories and six sub-categories.

Results

Health-promoting activities in individuals with knee pain were interpreted in the overall theme; enabling and maintaining a balance in everyday life based on abilities. Two categories explored the content in health-promoting activities as 1) Using facilitators to take care of the body with the sub-categories: being physically active, having a healthy diet, and using external resources. For example, the participants took care of the body by being physically active to decrease pain, reducing sugar intake and using external resources such as online workouts or help from health care. 2) Managing stressors of everyday life with the sub-categories: promoting vitality, allowing for recovery, and safeguarding healthy relationships. The participants managed stressors of life by, for example, being in nature, planning their work- and private life and spending time with friends and family. See Table 1.

Table 1.

Overview of the results exploring health-promotion activities in individuals with knee pain.

ThemeEnabling and maintaining a balance in everyday life based on abilitiesCategoryUsing facilitators to take care of the bodyManaging stressors of everyday lifeSub-categoriesBeing physically activeHaving a healthy dietUsing external resourcesPromoting vitalityAllows for recoverySafeguarding healthy relationship

Conclusion

Individuals with knee pain described various health-promoting activities, ranging from physical activity to social interactions, included in the theme of enabling and maintaining a balance in everyday life based on abilities. We suggest that a broader approach to everyday life can be helpful in treatment plans and health promotion to manage and prevent KOA and chronic pain while maintaining a healthy lifestyle.

References

[1]Thorstensson et al. Natural course of knee osteoarthritis in middle-aged subjects with knee pain…. ARD, 2009;68:1890-1893.

[2]Bergman et al. Chronic widespread pain and its associations with quality of life and function at a 20-year follow-up…. BMC Musculoskel, 2019;20:592

[3]Fernandes et al. EULAR recommendations for the non-pharmacological core management of hip and knee osteoarthritis. ARD, 2013;72:1128

Disclosure of Interests

None declared

AB1117 THE IMPACT OF THE COVID-19 PANDEMIC ON HEALTH AND LIFESTYLE IN INDIVIDUALS WITH KNEE PAIN, A HALLOA STUDY

Background

Covid-19 has affected everyday life, health and lifestyle among the general population and vulnerable groups. Individuals with knee pain are recommended an active lifestyle to reveal pain but find it difficult to maintain health and lifestyle compared to the general population due to the cause of chronic pain, impaired physical function and a diminishes quality of life. This adds to the importance of exploring how to preserve health and lifestyle among individuals with knee pain during the pandemic.

Objectives

The aim of this study was to explore the impact of the covid-19 pandemic on the health and lifestyle in individuals with knee pain.

Methods

Nineteen participants with current knee pain, and with no earlier diagnosed radiographic osteoarthritis, and no rheumatologic disorder or cruciate ligament injury, were recruited from The Halland Osteoarthritis (HALLOA) Cohort Study, twelve female and seven males, between 41-62 (median 51) years of age. Data were collected through individual interviews with open-ended questions: “What impact have you experienced with your health and lifestyle during covid-19?”, and “What activities or strategies have you changed to maintain your health and lifestyle during covid-19? ”. Qualitative content analysis was used, where two categories and five sub-categories emerged (Table 1).

Table 1.

Categories, and sub-categories exploring the impact of the covid-19 pandemic on health and lifestyle in individuals with knee pain

CategoriesSub-categoriesAdjusting behaviours due to covid-19Spending time at homeBecoming digitallySpending time outdoorsValuing life due to covid-19Having a positive outlook on lifeSharing responsibility

Results

The result from this study explored how behaviour and attitude towards valuing life have been adjusted to maintain health and lifestyle among individuals with knee pain during covid-19. The category adjusted behaviours emerged with the sub-categories: spending more time at home, becoming digitally, and spending more time outdoors. These sub-categories determine how a more reclusive behaviour have appeared due to the pandemic, where digital platforms and outdoor activities have facilitated companionship and togetherness when feelings of loneliness and isolation were present. The category valuing life emerged with the sub-categories: having a positive outlook of life and sharing responsibility. These sub-categories establish the importance of trying to be grateful for maintaining health and lifestyle and trying to be solution-oriented to find the best possible outcomes to continue with everyday life, despite the pandemic. While having a responsibility towards others arose as a facility to manage to keep social distance during the pandemic.

Conclusion

In conclusion, the behaviour was adjusted to continue with everyday life and maintain health and lifestyle among individuals with knee pain during covid-19. Valuing life was also considered important to maintain health and lifestyle as well as supporting others maintain their health and lifestyle. The result may in the future contribute to alternative ways of maintaining health and lifestyle in different vulnerable groups and may be used in situations other than the pandemic.

Disclosure of Interests

None declared

AB0586 PREVALENCE OF EARLY SYMPTOMATIC KNEE OSTEOARTHRITIS ACCORDING TO THREE CLINICAL CLASSIFICATION CRITERIA

Background:

Knee osteoarthritis (KOA) is a heterogeneous disease. Different classification criteria for symptomatic KOA (SKOA) have been proposed. Determining the prevalence and comparing the different criteria of SKOA in patients with knee pain will serve as a base when studying the predictive ability of these criteria in a longer perspective.

Objectives:

To study the prevalence of SKOA in individuals with knee pain according to three different classification criteria: the American College of Rheumatology (ACR), (1), the European League Against Rheumatism (EULAR)(2), and the National Institute for Health and Care Excellence (NICE) (3).

Methods:

Baseline data from an ongoing longitudinal study (HALLOA) including 296 individuals with knee pain, recruited by advertisement, were analysed. The individuals were categorized according to the classification criteria of SKOA (ACR, EULAR and NICE) based on age, clinical examination (crepitation), and self-reported data from KOOS (pain, symptoms, ADL, and sport/recreation), and dichotomized as fulfilling the criteria (SKOA) or not (no SKOA). BMI was measured (kg/m2). Radiographic KOA (RKOA) was assessed according to Ahlbäck criteria (1-5), defined as RKOA with grade 1 or more in at least one knee. Prevalence was calculated (frequencies, %) for each criterion, and Chi-Square test or the Independent-Samples t-test were used for comparisons between individuals fulfilling SKOA or not.

Results:

The mean age was 52 (min-max 24-73) years, 70% were women and 22% were classified with RKOA. The prevalence of SKOA according to each criterion was 57% (ACR), 51% (EULAR) and 73% (NICE) respectively. In total, 48% had SKOA according to all three criteria and whereof 32% had RKOA, compared to 10% RKOA among individuals with no SKOA. Regardless of the criterion, significantly more individuals classified with SKOA also had RKOA compared to individuals with no SKOA, p<0.001. Those classified as SKOA were significantly older and had higher BMI compared with no SKOA (Table 1).

Conclusion:

Approximately 50-70% of the individuals with knee pain were classified as having SKOA, where EULAR criteria had the lowest prevalence. A better understanding of early knee pain classification according to different clinical criteria is essential for the ability to capture and follow the long-term prognosis of early SKOA. Further longitudinal studies are needed.

References:

[1]Altman R et al. Arthritis Rheum. 1986;29(8):1039-49.

[2]Zhang W et al. Ann Rheum Dis. 2010;69(3):483-9.

[3]Health NIf, Excellence C. UK: National Institute for Clinical Excellence. 2014.

Table 1.

Comparisons between the ACR, EULAR and NICE criteria of symptomatic knee osteoarthritis, stratified for symptomatic knee osteoarthritis or not

ACREULARNICETotalOANo OAP-valueOANo OAP-valueOANo OAP-valueN(%)296 (100)170 (57.4)98 (33.1)152 (51.4)114 (38.5)215 (72.6)58 (19.6)Age(Y), Mean (SD)51.6 (8.7)53.3 (7.0)49.0 (10.3)<0.00154.5 (5.1)48.1 (10.8)<0.00154.7 (4.9)40.5 (9.8)<0.001Gender, female (%)208 (70.3)121 (71.2)66 (67.3)0.511108 (58.4)77 (67.5)0.538154 (71.6)36 (62.1)0.160BMI(kg/m2), Mean (SD)26.4 (4.6)26.5 (4.5)25.8 (4.3)0.17926.9 (4.5)25.4 (4.2)0.00526.7 (4.5)24.8 (3.8)0.004RKOA, n (%)64 (21.6) 45 (26.5)12 (12.2)0.00347 (30.9)10 (8.7)<0.00158 (27.0)1 (1.7)<0.001

Independent-samples t-test and Chi-2-test. Bold=Significant correlation (p≤0.05). OA = Osteoarthritis. ACR = American College of Rheumatology. EULAR = the European League Against Rheumatism. NICE = the National Institute of Care and Excellence. BMI = Body Mass Index. RKOA = Radiographic Knee Osteoarthritis (Ahlbäck, with grade ≥1 in ≥1 knee).

Disclosure of Interests:

None declared.

OP0336-HPR RISK FACTORS FOR PERSISTENCE AND DEVELOPMENT OF FREQUENT MUSCULOSKELETAL PAIN IN ADOLESCENT ATHLETES

Background:

Physical activity has a positive impact on health, but adolescent athletes often report musculoskeletal pain (MP) which is negative in the aspect of sustaining physical activity over time. There is a lack of longitudinal assessments of MP and potential risk factors, such as timing of physical maturation, in adolescent athletes.

Objectives:

To identify risk factors associated with the persistence or development of frequent MP at a 2-year follow-up in adolescent sport school students.

Methods:

Fourteen-year-old sport school students (n=233) were invited to participate in this 2-year longitudinal study. Self-reports of MP was assessed as frequency, distribution, and intensity, and health status by EQ-5D. Physical maturation was calculated by the Mirwald equation (height, weight, and sitting height) (1), and categorized as early (>1 year), average (±1 year), or late (<–1 year). Students were grouped at baseline and follow-up into infrequent (never to monthly) or frequent (weekly to daily) MP groups. Logistic regression analysis was used to study associations between frequent MP at follow-up and baseline variables.

Results:

131 students (79 boys and 52 girls) were included in the study. Development or persistence of frequent MP at follow-up (n=61) was associated with being a girl, late physical maturation (only boys were categorized as late), non-contact sports participation, frequent MP at baseline, and reporting ≥2 MP sites at baseline. Students with a better health status at baseline were less likely to belong to the frequent MP group at follow-up (Table).

Conclusion:

Frequent MP is common in sport school students. MP in young athletes may become a future health problem and there is a need for recognition and interventions by coaches and health services to prevent MP from becoming persistent.

References:

[1]Mirwald, R. L., Baxter-Jones, A. D., Bailey, D. A., & Beunen, G. P. (2002). An assessment of maturity from anthropometric measurements.Med Sci Sports Exerc, 34(4), 689-694.

Table.

Associations between background variables at baseline and frequent MP at follow-up based on crude logistic regression analysis controlling each variable for sex.

Baseline variablesModelInfrequent MP vs. Frequent MPOR(95% CI; p-value)SexBoys1.00Girls2.76(1.34–5.68; p<0.01)Physical maturationAverage (±1 year)1.00Early (>1 year)0.41(0.05–3.65; p=0.42)Late (<–1 year)3.83(1.13–12.95; p=0.03)Sport categoriesContact1.00Non-contact5.16(2.07–12.88; p<0.001)MP groupsInfrequent1.00Frequent2.74(1.31–5.72; p<0.01)MP intensity last week (NRS 0–10, best to worst)1.15(0.98–1.35; p=0.10)Number of MP sites01.0012.32(0.71–7.58; p=0.16)≥22.87(1.32–6.25; p<0.01)EQ-5D (0.00–1.00, worst to best)0.03(0.001–0.58; p=0.02)

Disclosure of Interests:

None declared

FRI0391 METABOLIC FACTORS ASSOCIATED TO RADIOGRAPHIC KNEE OSTEOARTHRITIS IN INDIVIDUALS WITH KNEE PAIN

Background:

Metabolic factors have been shown to be associated to radiographic knee osteoarthritis (OA) [1]. More knowledge about associations between metabolic factors and early clinical knee OA is needed.

Objectives:

The aim was to study associations between metabolic factors and radiographic knee OA in individuals with knee pain

Methods:

In total 272 individuals with radiographs at baseline, from an ongoing longitudinal study of knee pain (without cruciate ligament injury), were included in the present cross-sectional study. At baseline BMI, waist circumference (WC) and visceral fat area (VFA) were assessed. Fasting plasma glucose, triglycerides, cholesterol, HDL-and LDL-cholesterol were analysed. Metabolic syndrome (MetS) was present if central obesity (WC ≥94 cm in men and ≥80cm in women) plus any two of the following factors: raised blood pressure (systolic blood pressure ≥ 130 or diastolic blood pressure ≥ 85 mm Hg or treatment of hypertension), raised triglycerides (≥ 1.7 mmol/L or specific treatment), reduced HDL-cholesterol (men < 1.03 mmol/L and women < 1.29 mmol/L or specific treatment), raised glucose (glucose ≥ 5.6 mmol/L, or type 2 diabetes).

The individuals were divided in two groups according to Ahlbäck [2], one group, who had grade I or more in at least one knee (radiographic knee OA, ROA) n=62 and the other group, not fulfilling Ahlbäck criteria (no radiograhic knee OA, No OA) n=211. The associations between metabolic factors and knee OA were calculated by crude logistic regression analyses, adjusting for age and sex.

Results:

The group with radiographic knee OA were older, had higher BMI, higher amount of visceral fat and more had central obesity, table 1. Ninety- four percent of the group with ROA had central obesity compared to 76%, p=0.002 in the no OA group. There was no difference between the groups regarding MetS, 44% in the ROA group vs. 39%, p=0.5. The group with ROA had increased cholesterol, triglycerides and LDL-cholesterol. There were no differences in fasting glucose between the groups, though both groups had a mean glucose value in the upper range of normal value, table 1. Factors associated to having radiographic knee OA were age (OR 1.11, 95% CI 1.06-1.17), BMI (1.07, 1.003-1.13), central obesity (3.91, 1.32-11.61) and raised triglycerides (2.35, 1.03-5.38).

Table 1.

Baseline descriptives

No OAMean (sd)ROAMean(sd)p-valueN21162Age50 (9)56 (4)<0.001Sex, women, %66710.454BMI25.9 (4.7)27.7 (4.7)0.007VFA (cm2)109 (53)126 (52)0.026WC, cm94 (13)99 (13)0.006Raised Blood pressure, %66530.063Cholesterol (mmol/L)5.2 (1.0)5.5 (1.1)0.033Triglycerides (mmol/L)1.0 (0.6)1.2 (0.7)0.035Raised triglycerides, %9210.008LDL-cholesterol (mmol/L)3.4 (1.0)3.7 (1.1)0.027HDL-cholesterol (mmol/L)1.7 (0.4)1.7 (0.5)0.547Reduced HDL11150.460Glucose (mmol/L)5.5 (0.9)5.5 (0.5)0.858

Conclusion:

There were associations between some metabolic factors and radiographic knee OA in individuals with knee pain. Fasting glucose was increased in both groups. The associations between metabolic risk factors and the development of knee OA needs to be assessed in longitudinal studies.

References:

[1]Sellam J, Bone Spine 2013;80:568-73.

[2]Ahlback S,. Acta Radiol Diagn (Stockh) 1968Suppl 277:7-72.

Disclosure of Interests:

None declared

AB0854 METABOLIC FACTORS ASSOCIATED TO CLINICAL HAND OSTEOARTHRITIS IN INDIVIDUALS WITH KNEE PAIN

Background:

There is some evidence supporting associations between metabolic factors, clinical hand osteoarthritis (OA) and radiographic knee OA. However, more studies are needed regarding early knee OA.

Objectives:

The aim was to study associations between metabolic factors and clinical hand OA at baseline in a cohort of individuals with knee pain, with and without radiographic knee OA

Methods:

In an ongoing five-year longitudinal study of knee pain, hand OA was assessed by clinical examinations in 296 of the included individuals at baseline [1]. BMI, waist circumference (WC) and blood pressure was measured. Body composition was assessed with Inbody 770. Fasting plasma glucose, triglycerides, cholesterol, HDL-and LDL-cholesterol and HbA1c was analysed. Metabolic syndrome (MetS)was present if central obesity (WC ≥94 cm in men and ≥80cm in women) plus any two of the following factors: raised blood pressure (systolic blood pressure ≥ 130 or diastolic blood pressure ≥ 85 mm Hg or treatment of hypertension), raised triglycerides (≥ 1.7 mmol/L or specific treatment), reduced HDL-cholesterol (men < 1.03 mmol/L and women < 1.29 mmol/L or specific treatment), raised glucose (glucose ≥ 5.6 mmol/L, or type 2 diabetes). Hand strength and self-reported disability of the arm, shoulder and hand (quickDASH) was assessed.

The individuals were divided according to having clinical hand OA or not, according to Altman [1]. The associations between background factors and clinical hand OA were calculated by crude logistic regression analyses, adjusting for age and sex.

Results:

Fifty-five percent of the individuals in the study was overweight or obese, 40% had MetS and 23% had radiographic knee OA. In total 34% of the individuals had clinical hand OA. The group with hand OA were older, had higher proportion of body fat, fasting plasma glucose, HbA1C, worse quickDASH score and lower hand strength, table 1. Clinical hand OA was significantly associated to higher age (OR 1.04, 95%CI 1.01-1.07), higher fasting plasma glucose (1.56, 1.05-2.30), worse quickDASH (1.04, 1.02-1.06) and lower hand strength (0.99, 0.99 -0.998), but not to proportion of body fat and HbA1c.

Table 1.

Descriptives at baseline

No hand OAMean (sd)Hand OA*Mean(sd)p-valueN194102Age51 (9)53 (8)0.015Sex, women, %69730.374BMI26.2 (4.8)27.1 (4.7)0.114Visceral fat area (VFA)110 (53)122 (54)0.070Percentage of body fat*30 (9)32 (8)0.026Waist circumferance, cm95 (13)97 (13)0.226Central obesity, %77860.067Raised Blood pressure, %61650.492Cholesterol (mmol/l)5.2 (1.0)5.4 (1.2)0.317Triglycerides (mmol/L)1.0 (0.6)1.1 (0.7)0.078Raised triglycerides, %9160.075LDL-cholesterol (mmol/L)3.4 (1.0)3.5 (1.1)0.416HDL- cholesterol mmol/L)1.7 (0.4)1.8 (0.5)0.352Glucose (mmol/L)5.4 (0.5)5.6 (1.2)0.010HbA1c (mmol/L)36 (3)38 (6)0.016quickDASH11.5 (12.8)21.8 (18.6)<0.001Hand strength (N)291 (110)252 (103)0.004

Conclusion:

In this cross-sectional study, the only metabolic factor associated with clinical hand OA was fasting plasma glucose. Contrary to other studies, there were no gender differences found. The association between development of clinical hand OA and metabolic factors in individuals with knee pain need to be further assessed in longitudinal studies.

References:

[1]Altman R, Arthritis Rheum 1990;33:1601-10.

Disclosure of Interests:

None declared

OP0084 PRESSURE PAIN THRESHOLDS AND THE ASSOCIATIONS WITH CHRONIC WIDESPREAD PAIN, KNEE OSTEOARTHRITIS AND OBESITY IN INDIVIDUALS WITH KNEE PAIN

Background:

Approximate 30% of individuals with symptomatic knee osteoarthritis (OA) had developed chronic widespread pain (CWP) over a period of 20 years [1]. In order to prevent CWP in those with knee pain, it is important to study associated factors.

Objectives:

The aim was to study pressure pain thresholds among individuals with knee pain with or without radiographic changes, and associations with CWP, radiographic knee OA, and obesity.

Methods:

Out of 300 individuals with knee pain (with or without radiographic changes) from an ongoing longitudinal study, 279 conducted pressure pain thresholds (PPT) measurement at baseline in this cross-sectional study (71% women; mean age 51 years). The PPT were measured using a computerized pressure algometry on eight predefined tender points (Figure 1) out of the 18 points as part of the definition of fibromyalgia [2]. PPTs were dichotomised based on the lowest tertial vs the two higher tertials for each of the eight points. A group that had ≥4 points with low PPT (low PPT group) was compared to a group that had <4 low PPT (not low PPT group). A pain mannequin categorised the participants in three different pain groups: CWP, chronic regional pain (CRP), and no chronic pain (NCP) according to the definition of the ACR [2]. Radiographic knee OA was defined according to the Ahlbäck five grading scale as having score ≥1 vs score 0 [3]. Obesity was measured by bioimpedance measuring BMI and visceral fat area (VFA, cm2). To study associations, a crude logistic regression model controlled for age and sex was used including main and significant variables

Figure 1

Differences in mean PPT in the eight tender points

Results:

The prevalence of CWP was 37% and higher in the low PPT group compared to those in the not low PPT group (Table 1). No differences were found between the groups in BMI, VFA or radiographic knee OA (Table 1). The low PPT group had significantly lower mean PPT on all eight tender points, was younger, had more pain sites, and more cases of fibromyalgia compared to the group with not low PPT (Table 1, Figure 1). Age (OR 0.95; 95% CI 0.92–0.97), having CWP (OR 3.00; CI 1.66–5.06), fibromyalgia (OR 21.91; CI 2.45–194.69) and increased number of pain sites (OR 1.13; CI 1.05–1.22) were associated with low PPT.

Table 1.

Descriptive statistics for the whole sample and for the groups: low PPT and not low PPT

Alln = 279Low PPTn = 99Not low PPTn = 180p-valueAge, mean years (sd)51 (9)49 (9)53 (8)<0.001Women, n (%)197 (71%)69 (70%)128 (71%)0.804Pain group, n (%)<0.001 NCP/CRP160 (63%)41 (47%)119 (71%) CWP95 (37%)46 (53%)49 (29%)Numbers of pain sites, mean (sd)5 (4)6 (5)4 (3)0.003Fibromyalgia, n (%)8 (3%)7 (9%)1 (1%)0.001Knee OA Ahlbäck, n (%)59 (23%)16 (18%)43 (26%)0.132BMI, n (%)127 (48%)42 (47%)85 (48%)0.801 Normal Overweight/Obese139 (52%)48 (53%)91 (52%)VFA, mean cm2(sd)114 (54)115 (51)113 (55)0.788

Conclusion:

Baseline characteristics of individuals with knee pain showed a higher prevalence of CWP than in the general population [4]. In the group with low PPT, the prevalence was even higher. The study found associations between CWP and low PPT, however, almost half of the individuals with low PPT reported NCP/CRP. Moreover, a third in the group that not had low PPT reported CWP. The development of widespread pain in individuals with knee pain needs to be further studied over time to increase the knowledge of CWP’s origin in order to prevent the condition.

References:

[1]Bergman et al. BMC Musculoskelet Disord. 2019;20:592

[2]Wolfe et al. Arthritis Rheum. 1990;33:160-72

[3]Ahlbäck. Acta Radiol Diagn (Stockh). 1968:7-72

[4]Andrews et al. Eur J Pain. 2018;22:5-18

Disclosure of Interests:

None declared

The educational needs of patients with undifferentiated spondyloarthritis: Validation of the ENAT questionnaire and needs assessment

OBJECTIVES

The aim of the present study was to validate the Swedish version of the educational needs assessment tool (SwENAT) in undifferentiated spondyloarthritis (USpA) and use it to study the educational needs of patients with USpA.

METHODS

This was a cross-sectional study, recruiting a random sample of patients with USpA from a hospital register in Sweden. Educational needs data were collected, together with disease activity and function indices (Bath Ankylosing Spondylitis Disease Activity Index [BASDAI] and Bath Ankylosing Spondylitis Functional Index [BASFI]). Rasch analysis was utilized to evaluate the construct validity, internal consistency and unidimensionality of the SwENAT before studying differences in educational needs between patient subgroups (gender, age and disease severity).

RESULTS

Complete responses were obtained from 77 patients (48 women), with a mean age (standard deviation [SD]) of 50 (12) years, a disease duration of 16 (11) years, a BASDAI score of 4.9 (1.9) and a BASFI score of 3.1 (2.3). The SwENAT satisfied the requirements of the Rasch model (χ² = 11.488; p = 0.119), including strict unidimensionality. Overall, the mean (SD) SwENAT score was 86 (32). Women reported higher needs than men in the domains of pain (mean [SD] 13.1 [6.8] versus 10.1 [6.0]; p = 0.05); movement (mean [SD] 13.0 [5.5] versus 9.9 [5.7]; p = 0.02) and self-help (mean [SD] 17.0 [5.8] versus 14.1 [5.0]; p = 0.03). Higher disease activity (BASDAI >4) was associated with higher educational needs (mean [SD] 92.6 [31.9] versus 73.7 [29.4]; p = 0.02).

CONCLUSIONS

These data suggest that the SwENAT is valid in USpA. Women and patients with higher disease activity are more likely to have high levels of educational needs, so special attention and strategies to target patient education are warranted.

Demonstration of post-growth wavelength setting of VCSELs using high-contrast gratings

We demonstrate, for the first time, post-growth wavelength setting of electrically-injected vertical-cavity surface-emitting lasers (VCSELs) by using high-contrast gratings (HCGs) with different grating parameters. By fabricating HCGs with different duty cycle and period, the HCG reflection phase can be varied, in effect giving different optical cavity lengths for HCG-VCSELs with different grating parameters. This enables fabrication of monolithic multi-wavelength HCG-VCSEL arrays for wavelength-division multiplexing (WDM). The GaAs HCG is suspended in air by removing a sacrificial layer of InGaP. Electrically-injected 980-nm HCG-VCSELs with sub-mA threshold currents indicate high reflectivity from the GaAs HCGs. Lasing over a wavelength span of 15 nm was achieved, enabling a 4-channel WDM array with 5 nm channel spacing. A large wavelength setting span was enabled by an air-coupled cavity design and the use of only the HCG as top mirror.

European League Against Rheumatism (EULAR) recommendations for the management of psoriatic arthritis with pharmacological therapies: 2015 update

BACKGROUND

Since the publication of the European League Against Rheumatism recommendations for the pharmacological treatment of psoriatic arthritis (PsA) in 2012, new evidence and new therapeutic agents have emerged. The objective was to update these recommendations.

METHODS

A systematic literature review was performed regarding pharmacological treatment in PsA. Subsequently, recommendations were formulated based on the evidence and the expert opinion of the 34 Task Force members. Levels of evidence and strengths of recommendations were allocated.

RESULTS

The updated recommendations comprise 5 overarching principles and 10 recommendations, covering pharmacological therapies for PsA from non-steroidal anti-inflammatory drugs (NSAIDs), to conventional synthetic (csDMARD) and biological (bDMARD) disease-modifying antirheumatic drugs, whatever their mode of action, taking articular and extra-articular manifestations of PsA into account, but focusing on musculoskeletal involvement. The overarching principles address the need for shared decision-making and treatment objectives. The recommendations address csDMARDs as an initial therapy after failure of NSAIDs and local therapy for active disease, followed, if necessary, by a bDMARD or a targeted synthetic DMARD (tsDMARD). The first bDMARD would usually be a tumour necrosis factor (TNF) inhibitor. bDMARDs targeting interleukin (IL)12/23 (ustekinumab) or IL-17 pathways (secukinumab) may be used in patients for whom TNF inhibitors are inappropriate and a tsDMARD such as a phosphodiesterase 4-inhibitor (apremilast) if bDMARDs are inappropriate. If the first bDMARD strategy fails, any other bDMARD or tsDMARD may be used.

CONCLUSIONS

These recommendations provide stakeholders with an updated consensus on the pharmacological treatment of PsA and strategies to reach optimal outcomes in PsA, based on a combination of evidence and expert opinion.

Prevalence of spondyloarthritis and its subtypes in southern Sweden

Objective

To estimate the prevalence of spondyloarthritis and its subtypes.

Methods

The Swedish healthcare organisation comprises a system where all inpatient and outpatient care is registered by a personal identifier. For the calendar years 2003–7, all residents aged ≥15 years in the southernmost county of Sweden (1.2 million inhabitants) diagnosed by a physician with spondyloarthritis (ankylosing spondylitis (AS), psoriatic arthritis (PsA), inflammatory arthritis associated with inflammatory bowel disease (Aa-IBD) or undifferentiated spondylarthritis (USpA)) were identified. To obtain valid point estimates of prevalence by the end of 2007, identification numbers were cross-referenced with the population register to exclude patients who had died or relocated.

Results

The authors estimated the prevalence of spondyloarthritis (not including chronic reactive arthritis) as 0.45% (95% CI 0.44% to 0.47%). The mean (SD) age of patients with prevalent spondyloarthritis by the end of 2007 was 53 (15) years. Among the component subtypes, PsA accounted for 54% of cases, AS 21.4%, USpA 17.8% and Aa-IBD 2.3% with a prevalence of 0.25%, 0.12%, 0.10% and 0.015%, respectively. The remaining 6.4% had some form of combination of spondyloarthritis diagnoses. The prevalence of spondyloarthritis at large was about the same in men and women. However, the subtype PsA was more prevalent in women and AS was more prevalent in men.

Conclusion

In Sweden the prevalence of spondyloarthritis leading to a doctor consultation is not much lower than rheumatoid arthritis. PsA was the most frequent subtype followed by AS and USpA, and the two most frequent subtypes PsA and AS also display some distinct sex patterns.

Intraperitoneal alpha-radioimmunotherapy in mice using different specific activities

PURPOSE

The aim of this study was to investigate the therapeutic efficacy of the alpha-radioimmunotherapy of ovarian cancer in mice, using different specific activities. This study was performed by using the monoclonal antibody, MX35 F(ab')(2), labeled with the alpha-particle-emitter, 211At.

METHODS

Animals were intraperitoneally inoculated with approximately 1 x 10(7) cells of the cell line, NIH:OVCAR-3. Four (4) weeks later, five groups of animals were given 400 kBq of 211At-MX35 F(ab')(2) with specific activities equal to 130, 65, 32, 16, or 4 kBq/microg, respectively (n = 18 in each group). As controls, animals were given unlabeled MX35 F(ab')(2) (n = 12). Eight (8) weeks after treatment, the animals were sacrificed and the presence of macro- and microscopic tumors and ascites was determined.

RESULTS

The tumor-free fractions (TFFs) of the animals, defined as the fraction of animals with no macro- and microtumors and no ascites, were 0.67, 0.73, 0.50, 0.50, and 0.17 when treated as above. Only the TFF of 0.17, for the specific activity of 4 kBq/microg, was significantly less, compared to that of the specific activity of 130 kBq/microg. The TFF for the specific activity of 4 kBq/microg showed a significant lowering, compared to the specific activity of 130 kBq/microg (p < 0.05). Treatment with unlabeled MX35 F(ab')(2) resulted in a TFF of zero.

CONCLUSIONS

A specific activity-dependent therapeutic outcome could not be shown in the interval of 130- to 16 kBq/mug. For lower specific activities (i.e., 4 kBq/microg), the therapeutic efficacy was significantly lowered.

Direct procedure for the production of 211At-labeled antibodies with an epsilon-lysyl-3-(trimethylstannyl)benzamide immunoconjugate

(211)At-labeled tumor-specific antibodies have long been considered for the treatment of disseminated cancer. However, the limited availability of the nuclide and the poor efficacy of labeling procedures at clinical activity levels present major obstacles to their use. This study evaluated a procedure for the direct astatination of antibodies for the production of clinical activity levels.

METHODS

The monoclonal antibody trastuzumab was conjugated with the reagent N-succinimidyl-3-(trimethylstannyl)benzoate, and the immunoconjugate was labeled with astatine. Before astatination of the conjugated antibody, the nuclide was activated with N-iodosuccinimide. The labeling reaction was evaluated in terms of reaction time, volume of reaction solvent, immunoconjugate concentration, and applied activity. The quality of the astatinated antibodies was determined by in vitro analysis and biodistribution studies in nude mice.

RESULTS

The reaction proceeded almost instantaneously, and the results indicated a low dependence on immunoconjugate concentration and applied activity. Radiochemical labeling yields were in the range of 68%-81%, and a specific radioactivity of up to 1 GBq/mg could be achieved. Stability and radiochemical purity were equal to or better than those attained with a conventional 2-step procedure. Dissociation constants for directly astatinated, conventionally astatinated, and radioiodinated trastuzumab were 1.0+/-0.06 (mean+/-SD), 0.44+/-0.06, and 0.29+/-0.02 nM, respectively. The tissue distribution in non-tumor-bearing nude mice revealed only minor differences in organ uptake relative to that obtained with the conventional method.

CONCLUSION

The direct astatination procedure enables the high-yield production of astatinated antibodies with radioactivity in the amounts required for clinical applications.

Influence of metoprolol CR/ZOK on plasminogen activator inhibitor (PAI-1) in man: a pilot study

Recent primary and secondary preventive trials have shown that long-term metoprolol therapy reduces the risk of acute cardiovascular complications. To test whether part of this beneficial long-term effect may be due to effects on the fibrinolytic system, three pilot studies were performed; two in healthy individuals, and one in patients with mild hypertension or uncomplicated atrial fibrillation. The effect of metoprolol CR/ZOK (controlled release) 100-200 mg daily, on plasminogen activator inhibitor activity (PAI-1) in plasma was measured. In addition serum triglycerides and orosomucoid were analyzed. All the individuals were included in double-blind placebo controlled cross-over trials with treatment periods ranging from 4 days to 3 weeks. During metoprolol therapy PAI-1 values were reduced, while orosomucoid and triglyceride levels were unchanged. A linear inverse correlation was found between fibrinolysis and PAI-1 activity in plasma, indicating that PAI-1 activity serves as an indicator of fibrinolysis. PAI-1 activity and triglycerides were significantly correlated during placebo and metoprolol therapy. In conclusion, our results in these pilot studies suggest that metoprolol enhances fibrinolytic activity as seen by reduced PAI-1 activity. These results should be further confirmed and put into relation of clinical effects of the therapy.