Physician and patient perceptions of surgical procedures for osteoarthritis of the knee in the United States, Europe, and Japan: results of a real-world study

BACKGROUND

Osteoarthritis (OA) is the most common form of arthritis, with the knee being the joint most frequently affected, and symptomatic knee OA affecting around one quarter of the general population. For patients who do not respond to non-pharmacologic or pharmacologic treatment, surgery is a recommended option. The objectives of this study were to compare the willingness of patients with knee OA to undergo surgery, together with reasons for delaying surgery, and factors affecting successful outcomes.

METHODS

A point-in-time survey was conducted in 729 primary care physicians, rheumatologists, orthopedic surgeons, and 2,316 patients with knee OA across three geographical regions: Japan, the United States (US), and Europe (EUR: France, Spain, Italy, Germany, and the United Kingdom), in order to garner their perceptions of knee surgery. Regression models were used to identify factors that might affect patients' and physicians' perceptions of surgery, including severity of OA (mild/moderate/severe), number of affected joints, surgery status, and willingness to undergo or delay surgery.

RESULTS

Baseline demographics were similar between US and EUR, although patients in Japan were more likely to be female, older, and only 7% in fulltime employment. We found that few patients with end-stage knee OA, across all regions, but particularly Japan, were willing to undergo surgery (Japan 17%, US 32%, EUR 38%), either through fear, or the lack of awareness of the risk/benefits. Moreover, surgeons are prepared to delay surgery in elderly or unwilling patients, due to their dissatisfaction with the outcome, and may defer surgery in younger patients due to the need for future revision. We also identified a disconnect between physicians, of whom over 80% consider improved functioning to be the most important outcome of surgery, and patients, who seek pain relief (Japan 60%, US 35%, EUR 14%). Since physicians across all regions considered pain reduction to be an indication of surgery success (Japan 27%, US 47%, EUR 43%), this may indicate a need for improved communication to patients on the potential benefits of surgery.

CONCLUSION

Managing the expectations of patients undergoing surgery remains an important goal in the treatment of knee OA and may help guide physician choice.

POS0128 PHYSICIAN AND PATIENT PERCEPTIONS OF SURGICAL PROCEDURES FOR KNEE OA ACROSS JAPAN, THE US AND 5 EU COUNTRIES: RESULTS OF A REAL-WORLD STUDY

Background:

Patients with knee osteoarthritis (OA) who do not achieve adequate pain relief and functional improvement with a combination of non-pharmacologic and pharmacologic therapies are recommended an arthroplasty as an effective option to relieve severe pain and functional limitations. However, some patients are reluctant to undergo surgical interventions, and clinicians may choose to avoid or delay surgery due to safety risks and/or the financial cost. It is of interest to understand if the use and perception of surgery differs between countries, however, few published data exist.

Objectives:

To demonstrate how surgery and the use of surgical procedures differs across Japan, United States of America (US) and 5 major European countries (EU5) and to evaluate patient perception towards surgery.

Methods:

Data were drawn from the Adelphi OA Disease Specific Programme (2017-18), a point-in-time survey of primary care physicians (PCP), rheumatologists (rheums), orthopaedic surgeons (orthos) and their OA patients. Patients with physician-diagnosed knee OA were included and segmented into two categories: had previous surgery (PS) and never had surgery (NS). A Fisher’s exact test was performed on the two groups. Physicians reported on patient demographics; whether patients had undergone surgery; type of surgery; success of surgery; how success was defined; and reasons for wanting to delay surgery. Patients reported their willingness to undergo surgery; reasons for not wanting surgery; how successful their surgery was; and how they defined this success.

Results:

Physician/patient reported data were available for 302,230 (Japan), 527,283 (US) and 1487,726 (EU5) patients with diagnosed knee OA. Patients were categorised by their physicians as mild (40% Japan; 34% US; 24% EU5), moderate (49% Japan; 49% US; 56% EU5) or severe (9% Japan; 17% US; 19% EU5). Patients in Japan were more likely to be female (78% vs 54% US; 58% EU5), older (73 vs 65 US; 66 EU5) and have a lower BMI than patients in the US and EU5. Obesity and diabetes were much less prevalent among patients in Japan. One in ten patients in Japan had undergone a surgery (10%), far fewer than in the US (22%) or EU5 (17%). When surgery was performed, this was more likely to be a total joint replacement (TJR) in Japan, whereas in the EU and US, arthroscopic washout was more commonly performed.

For over half of Japanese patients (56%), successful surgery was more likely to be defined as having no more pain (vs. 35% US; 14% EU5). Improved mobility and a reduction in pain were also commonly reported reasons. Physicians (in each region) were more likely to suggest pain reduction, rather than no pain, and improved mobility as markers of success. Patients in Japan were much more likely to say they would not agree to surgery if recommended by their doctor, or were unsure (84% vs. 68% US; 62% EU5). The main reason for patient reluctance in Japan was fear of surgery, whereas in the US and EU5 the main reason given was that surgery was not needed. This finding was also evident among physicians in Japan, who frequently reported that patient reluctance was a key reason for delaying surgery. Physicians in Japan, do however, report that patient request was one of their main triggers for recommending surgery (45% vs 20% US; 16% EU5).

Conclusion:

Although surgery can be an effective option for those with OA who have exhausted other treatment options, some patients are reluctant to undergo surgery out of fear, especially in Japan, possibly due to the higher patient age. Physicians aiming to delay surgery were driven by patient reluctance in Japan, whereas cost to patient was a bigger factor in the US and EU5. The higher level of TJR vs. other surgery options among patients in Japan may suggest physicians are looking for higher levels of efficacy.

Disclosure of Interests:

Naoshi Fukui Speakers bureau: Pfizer, Consultant of: Pfizer, Philip G Conaghan Speakers bureau: Abbvie, Novartis, Consultant of: AstraZeneca, BMS, Eli Lilly, EMD Serono, Flexion Therapeutics, Galapagos, Gilead, Novartis, Pfizer, Kanae Togo Shareholder of: Pfizer, Employee of: Pfizer, Nozomi Ebata Shareholder of: Pfizer, Employee of: Pfizer, Lucy Abraham Shareholder of: Pfizer, Employee of: Pfizer, James Jackson: None declared, Jessica Jackson: None declared, Mia Berry: None declared, Hemant Pandit Paid instructor for: Bristol Myers Squibb, Consultant of: Johnson and Johnson, Grant/research support from: GSK

Production of colony-stimulating factor in human dental pulp fibroblasts

Class II major histocompatilibity complex (MHC)-expressing cells are usually distributed in dental pulp, and it was postulated that the colony-stimulating factor (CSF) derived from dental pulp fibroblasts contributes to the migration of class II MHC-expressing cells into pulp tissue. This study aimed to investigate the CSF production of human dental pulp fibroblasts. In pulp tissue sections, granulocyte (G)-CSF was detected from normal teeth, while G-CSF, macrophage (M)-CSF, and granulocyte-macrophage (GM)-CSF were detected from teeth with dentinal caries. In cultured dental pulp fibroblasts, G-CSF was detected by immunostaining, immunoprecipitation, and ELISA, and mRNAs of G-CSF, M-CSF, and GM-CSF were detected by RT-PCR. The dental pulp fibroblasts cultured with TNF-alpha were found to increase the G-CSF expression and to produce M-CSF and GM-CSF. These findings suggest that dental pulp fibroblasts usually produce G-CSF. In the presence of TNF-alpha, dental pulp fibroblast express M-CSF and GM-CSF.

Immunoelectron microscopic study of PECAM-1 expression on lymphatic endothelium of the human tongue

The expression of platelet-endothelial cell adhesion molecule-1 (PECAM-1) on lymphatic and blood vessels of the human tongue was examined with fluorescence and transmission electron microscopy (TEM). The study used anti-desmoplakins antiserum for light microscopic identification of the lymphatic vessels, plus a pre-embedding immunogold electron microscopic technique for TEM observations. Before making TEM observations, cryostat serial sections were immunostained with anti-desmoplakins or anti-PECAM-1 and then embedded. Semithin sections from each cryostat section were photographed under a light microscope and compared in order to identify the lymphatic vessels expressing PECAM-1. In fluorescence microscopy, PECAM-1 expression on lymphatic vessels was weaker than that on blood vessels. TEM observations showed that PECAM-1 expression on the blood vessels was observed only on the luminal surface of the endothelium. In lymphatic vessels, PECAM-1 expression was found both on the luminal and abluminal surfaces of the endothelium. The density of the PECAM-1 reaction products was lower in lymphatic vessels than in blood vessels. The density of PECAM-1 reaction products on the luminal surface of lymphatic vessels was higher than on the abluminal surfaces. The results suggest that blood vessels are more active than lymphatic vessels in leukocyte migration. The expression of PECAM-1 on the abluminal surface of lymphatic endothelium may allow leukocytes to adhere to the endothelium and interact in their migration from tissue into lymphatic vessels.

Desmoplakin as a specific marker of lymphatic vessels

The usefulness of immunostaining with anti-desmoplakin antibody for light microscopic identification of lymphatic vessels was examined in cryostat sections of the human tongue. The results were compared with laminin, 5'-nucleotidase (5'-Nase), and factor VIII staining. Immunoelectron microscopic observation was also performed to confirm that the vessels reacting with anti-desmoplakin were lymphatic vessels. Under the immunoelectron microscopic, the vessels reacting with anti-desmoplakin showed ultrastructural features characteristic of lymphatic vessels: thin endothelial walls, no or incomplete basal lamina, open junctions, and overlapping endothelium. In general, lymphatic vessels identified by anti-desmoplakin reacted strongly with 5'-Nase, but showed weak or no reactivity with anti-laminin and anti-factor VIII. Blood vessels showed no reactivity with anti-desmoplakin, but reacted strongly with anti-laminin and anti-factor VIII. However, some blood and lymphatic vessels showed intermediate reactivity with anti-laminin, anti-factor VIII, and 5'-Nase. It was difficult to identify these as blood or lymphatic vessels only by the reactivity differences. The results indicate that anti-desmoplakin antibody specifically distinguishes lymphatic vessels and is useful for studying the fine distribution of lymphatic vessels under light microscopy.

Double expressions of connexin 43 and 32 in human periodontal ligament fibroblasts

The expressions of connexin 43 and 32 in cultured and intact human periodontal ligament fibroblasts (PDLFs) were examined using immunohistochemical methods, and western blot analysis was conducted with anti-connexin 43 and 32 in cultured PDLFs. The PDLFs both in cultured cells and tissue sections reacted with anti-connexin 43 and 32, and western blot analysis showed bands of approximately 43 kD and 27 kD reacted with anti-connexin 43 and 32 respectively, suggesting the existence of gap junctions in human PDLFs. In cultured PDLFs there were no reaction products of connexin 43 when the cells were not in contact with adjacent cells, but reaction products were increasingly observed with increases in cell-cell contacts. Different from connexin 43, the reaction products of connexin 32 were found in the cytoplasm, regardless of whether the cells were or were not in contact with adjacent cells. Further, the reaction activity of connexin 32 varied among PDLFs; some were strong, some moderate, and some weak. The expressions of connexin 43 and 32 in human PDLFs are suggested to be related to the regulation of two different functions of the PDLFs.

Desmosomal proteins in cultured and intact human periodontal ligament fibroblasts

This study examined the kinds of desmosomal proteins in the human periodontal ligament fibroblasts (PDLFs). The PDLFs obtained from young and older patients were cultured and the amounts of desmosomal proteins were measured by ELISA with antibodies to desmoplakins, desmogleins, and desmocollins. Cultured cells and tissue sections of the human periodontal ligament were immunostained with the same antibodies. Expression of desmosomal proteins in the PDLFs was clearly demonstrated both by ELISA and the immunohistochemical studies, suggesting the existence of desmosome-like junctions in the PDLFs. The junctions are considered to protect gap junctions in the PDLFs against cell transformation caused by cell contraction, which may relate to tooth eruption and repair of periodontal tissue, and/or strong occlusal forces. Statistically significant differences (P < 0.0001) in the expression of desmoplakins and desmogleins between younger and older patients were observed in this study.

Immunohistochemical study on leukocyte adhesion molecules expressed on lymphatic endothelium

Leukocyte adhesion molecules expressed on the lymphatic endothelium in human small intestine and submandibular lymph node were studied immunohistochemically. Lymphatic capillaries in the lamina propria, mucosal muscle layer, and submucosal connective tissue of the intestine and in the capsule of the lymph node showed strong expression of platelet-endothelial cell adhesion molecule-1 (PECAM-1). A few lymphatic capillaries that weakly expressed intercellular adhesion molecule-1 (ICAM-1) were found in the capsule of the lymph node but in the small intestine, no lymphatic capillaries expressed detectable amounts of ICAM-1. Lymphatic capillaries also did not express detectable amounts of endothelial cell-selectin in the small intestine and lymph node. When lymphocytes migrate from tissue into lymphatic capillaries, multiple adhesion molecules may not be required for the migration. PECAM-1, however, may contribute to adherence of lymphocytes to lymphatic endothelium and the expression of adhesion molecules on lymphatic endothelium may be different between tissues.

Lymphatic endothelium of the human tongue expresses multiple leukocyte adhesion molecules

The expression of leukocyte adhesion molecules on lymphatic vessels of the human tongue was examined using histochemical and immunohistochemical methods. Three different types of lymphatic vessels were distinguished: type I vessels expressed intercellular adhesion molecule-1 (ICAM-1), platelet-endothelial cell adhesion molecule-1 (PECAM-1), and endothelial cell-selectin (ELAM-1); type II vessels expressed ICAM-1 and PECAM-1; and type III vessels expressed PECAM-1 only. The lymphatic vessels located very close to the oral epithelium (lymphatic capillaries) and the other lymphatic vessels near the oral epithelium were type I. The lymphatic vessels in the submucosal connective tissue (collecting lymphatic vessels) were type II and type III. The results suggest that there may be functional differences in the lymphatic endothelium, where lymphatic capillaries are more active than collecting lymphatic vessels in lymphocyte migration from tissue into the lymphatic vessels.

Saponins from the root of Bupleurum falcatum

Three new saponins and nine known saponins were isolated from the dried roots of Bupleurum falcatum. On the basis of chemical and spectral analyses, the structures of new compounds, named 4''-O-acetylsaikosaponin d and hydroxysaikosaponins a and c, were established. In aqueous acidic conditions, saikosaponins a and d were converted into not only known compounds, saikosaponins b1 and b2, but also hydroxysaikosaponins a and d, respectively. Furthermore, quantitative analysis of the decoction of Bupleuri Radix itself by HPLC exhibited that it contained saikosaponins a, c and d, and hydroxysaikosaponins a, c and d.

Quantitation of apolipoprotein A-I in pooled human serum by single radial immunodiffusion and sodium dodecyl sulfate-polyacrylamide gel electrophoresis

Apolipoprotein A-I was released from human HDL particles by treatment with 8 M urea, and the free apolipoprotein exhibited identical antigenicity and the same low mobility as purified apolipoprotein A-I in electrophoresis. Treatment of serum with 8 M urea enabled enabled quantitation of apolipoprotein A-I by single radial immunodiffusion assay, as judged by comparison with sodium dodecyl sulfate-polyacrylamide gel electrophoresis.

Silver stain for detecting 10-femtogram quantities of protein after polyacrylamide gel electrophoresis

A rapid and highly sensitive silver stain and color stain were developed for visualizing proteins. The procedure is simple and the bands were clear. This silver stain detects 100 pg quantities of proteins. In order to stain quickly, sensitively, and sharply a protein matrix in a gel, the repeated shrinkage and swelling gel was developed with a hyper- and hypotonic solution to remove the sodium dodecyl sulfate (SDS) from SDS-protein complex and to generate influx of staining solution into the gel. We have found that the silver staining method with the repeated exposure to hyper- and hypotonic solution and a narrow well produced 10 fg order of proteins.

Occurrence of four subunits in high molecular weight forms of polypeptide chain elongation factor 1 from wheat embryo

In contrast to high molecular weight forms of elongation factor 1 (EF-1H) from animal sources which contain three subunits, EF-1a, EF-1b, and EF-1c, EF-1H from wheat embryo consisted of four subunits, EF-1a, EF-1b, EF-1b', and EF-1c, in an equimolar ratio. The molecular weights of EF-1a, EF-1b, EF-1b', and EF-1c from wheat embryo were 52,000, 29,000, 28,000, and 48,000, respectively. In the animal system, EF-1a and EF-1b correspond functionally to EF-Tu and EF-Ts, respectively. In the wheat system, however, both EF-1b and EF-1b' had the EF-Ts-like activity to stimulate EF-1a-dependent binding of aminoacyl-tRNA to ribosomes. EF-1b and EF-1b' from wheat embryo gave 21 and 20 tryptic peptides, respectively. Twenty peptides were common.

Generation of spontaneous respiratory rhythm in high spinal cats

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