Rheumatoid Arthritis
Disease Characteristics
Incidence
United States
Female
321/100,000
Male
145/100,000
Worldwide
2-3 times higher in women than men
higher in pregnant women
Worldwide distribution 1-2%
Prevalence increases with age
5% in women over 55
UK
Males
10-11/100,000
Females
27-30/100,000
It existed in early Native American populations several thousand years ago but might not have appeared in Europe until the 17th century.
Geography
More prevalent in some subsets of Native Americans
Worldwide distribution
Symptoms
Symptoms
Nodules under skin
Numbness/tingling
Red inflamed eyes/discharge from eyes
high fever/signs of infection
bone fracture
Tendency to bruise
Difficulty Breathing/Chest pain
Loss of range of motion
Joint pain
Morning Stiffness
Risk Factors
50% Genetic factor
Sex, age, family
Increases with age 35-50
Relatives have 2-3x increase chance of RA
Women are affected 3x more than men
environment
Infection by P. gingivalis
Growing up under drug-alcohol addicted parents
Smoking
Reproductive Hormone
Current Treatment
Financial review
Direct costs
Treatment cost
Cost of using DMARDs (CyA, Methotrexate, sulphasalazine)
TNF blocking agents though comparatively higher in cost.
Genetically engineered drugs on an average cost about $1000-$3000 per month depending on the stage of RA.
Cost of diagnosis and laboratory tests
Hospital visits- these account for about US$1855 to US$4944
ESR, RF test and X rays- These lab tests cost $25- $30 each on an average. Multiple tests need to be conducted, hence COI (Cost of Illness) rises in the long run.
Indirect costs
Morbidity - Losses due to restriction from illness.
Morality cost- Calculated present value of lost production due to death caused by RA.
Current Treatments
NSAIDs
Corticosteroids
Prednisone, Methylprenisolone, Medrol
DMARDs
Methotrexate, Hydroxychloroquine,Sulfasalazine, Leflunomide, Tumor Necrosis Factor Inhibitor, T Cell Costimulatory Blocking Agents, B cell depleting agents, Interleukin-1 (IL-1) Receptor Antagonist Therapy, Intramuscular Gold
Biologics
Actemra,Cimzia,Enbrel,Humira,Kineret, Orencia, Remicade, Rituxan, Simponi
Surgical treatment
Synovectomy, Arthrodesis, Arthroplasty
Diagnosis
no definitive lab test that diagnoses
Genetic Predisposition
Candidate Genes with SNPs Linked to RA and Their Potential Function
in Pathogenesis
Positive rheumatoid factor 70-80%
Baseline X-Rays (hands, feet, affected joints, and sometimes a baseline chest X-Ray)
2010 ACR/EULAR criteria
Cytokine profile
Molecular Basis
RA Synovial Fibroblasts (RASF) - prime player in joint destruction of RA patients
IL-15 = proinflammatory cytokine produced by RASF
Positive-feedback loop through activation of T cells which activate more RASF
Toll-like receptors (TLRs) involved in initial onset of innate immune response of inflammation
A3AR receptor activation leads to apoptosis of inflammatory cells
A3AR agonists = proliferation of fibroblast-like synoviocytes
inhibition of pro-inflammatory cytokines
transcription factors such as nuclear factor κB, cytokines, chemokines, growth factors, cellular ligands, and adhesion molecules.
Cytokine-independent pathways responsible for maintaining basic disease activity
Currently Used Biomarkers
MiRNAs
Different concentrations of miRNAs found in synovial fluid of RA individuals
miRNA-125 levels at onset of RA is indicative of effectiveness of treatment with rituximab
Cytokines
ability to check cytokine levels throughout treatment as a way of observing disease prognosis
Urinary Peptide Markers
ID of 39 peptides that were significantly different in cases of RA versus controls
Proposed Treatment
Unmet Needs
Current conventional and biologic disease- modifying therapies fail/produce partial responses
Molecular remission & reestablishing immunologic tolerance
Predictive biomarkers (prognosis, therapeutic response, and toxicity) lacking
Sustained remission rare; requires ongoing pharmacologic therapy
Pathogenic mechanisms that initiate and perpetuate rheumatoid arthritis needs clarification
Early Diagnosis
Urine
Possible early rheumatoid arthritis biomarkers
Combination therapy
Methotrexate monotherapy vs triple DMARDS
Etanerept plus methotrexate
Using biologic agents with a DMARD is not superior to using multiple DMARDs
Approved Immune-Targeted Therapies
The Pathogenesis of Rheumatoid Arthritis