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Arthritis and rheumatoid arthritis

Osteoarthritis and rheumatoid arthritis

If you’re finding it more and more difficult to get out of bed in the morning, and it’s not because you are staying up late, but rather because your knees seem to be seizing up, then it’s possible you are developing a bit of arthritis in your joints. As an older adult it is very common to experience joint pain due to either osteoarthritis or rheumatoid arthritis. Although both of these conditions cause joint pain, the biological basis for the pain and stiffness is different:
  • Osteoarthritis occurs when your body can no longer properly repair the wear-and-tear that occurs in your joints from using them on a daily basis. Over time, the cartilage at the ends of your bones starts to wear out, which prevents your joints from moving smoothly, causing pain and inflammation. Osteoarthritis is also known as degenerative joint disease.
  • Rheumatoid arthritis on the other hand, is an autoimmune disease in which your own immune system attacks your own tissues, in this case, your joints. This causes chronic inflammation, painful swelling, and and can lead to joint deformity.

How joints work and what can go wrong

Most of the moveable joints between the bones of your body are synovial joints. In these joints, the ends of the two bones are covered in a smooth, slippery layer of cartilage that acts as a shock absorber. The joint capsule contains a lubricating fluid, called synovial fluid, which is a bit like teflon on a frying pan in that it makes everything “non-stick”, which helps your bones glide past each other when you bend the joint.
Osteoarthritis - in this disease, the top layer of the cartilage covering the bones within the joint softens, breaks down, and wears away, which allows the bones underneath to rub against each other every time you bend. The continual grating causes the ends of the bones to thicken, narrowing the gap between them, which causes pain, swelling and loss of motion in the joint. Everyone’s joints undergo wear-and-tear over time, but osteoarthritis is more than just that, as we now know that it is a disease that affects the entire joint including the cartilage, synovial membranes, ligaments, and bone. Sometimes bits of frayed cartilage or bone fragments can break off inside the joint, causing more pain and damage. Osteoarthritis can damage any joint in your body, but most commonly occurs in the weight-bearing joints including your knees, hips and spine, often starting in just one joint. Other joints that have been previously injured or overused may also be affected, e.g., the joints in your hands.
Rheumatoid arthritis - this disease is caused by an autoimmune disease, which means your immune system produces antibodies that attack your own tissues. In this case, the “autoantibodies” attack the synovial membrane inside your joints, causing inflammation and fluid build up within the joint capsule. Over time, the joint surface begins to erode, restricting your movement, and often eventually causing your joints to become deformed.
Diagram comparing normal joints, joints with osteoarthritis, and joints with rheumatoid arthritis
Image showing boutonniere deformity and swan-neck deformity in finger joints.

What are the signs and symptoms of arthritis?

Osteoarthritis and rheumatoid arthritis are similar in that they both cause joint pain and stiffness, However, there are ways to tell them apart:
OsteoarthritisRheumatoid arthritis
Deep, achy joint pain that worsens with movement and activity.Tender, warm, swollen, painful joints.
Loss of flexibility, especially if you have been stationary for a while.Morning stiffness that may last for several hours.
Bony lumps around the joint.A general feeling of being tired and unwell, which may be accompanied by fever and weight loss.
If you have osteoarthritis, it will usually develop slowly and get worse over time. Joint pain often worsens when you are more active and eases when you rest; although as the disease progresses, you may find you are in pain most, or even all of the time.
With rheumatoid arthritis, joint problems usually begin in your hands and feet, but as this disease progresses, your wrists, elbows, ankles, knees, hips, and shoulders may also be affected. For most people, the symptoms appear in the same joints on both sides of the body at the same time. Later in the course of the disease, other tissues and organs such as your skin, lungs, and blood vessels may also become inflamed. In some cases, rheumatoid arthritis will flare up, and your symptoms will be worse; however, after these flares calm down, they are often followed by periods of time where your symptoms fade and may even disappear altogether.

What factors predispose you to arthritis?

Osteoarthritis and rheumatoid arthritis have overlapping and distinct risk factors. The overlapping risk factors are:
OsteoarthritisRheumatoid arthritis
Age - can occur at any age, but is most common after the age of 60.Age - can occur at any age, but most commonly begins between 40 and 60 years of age.
Gender - more common in women than men.Gender - more common in women than in men.
Family history - tends to run in families.Family history - tends to run in families.
Several other factors have been identified that may increase your chances of developing osteoarthritis including obesity, joint injuries, having a high wear-and-tear occupation such as being a farm worker or professional athlete, bone deformities, and having other diseases including diabetes, rheumatoid arthritis, or other rheumatic diseases. It has been more challenging to pinpoint risk factors for rheumatoid arthritis. So far, cigarette smoking is the only factor that has consistently been found to increase risk.

How common is arthritis?

Osteoarthritis is the most common form of arthritis and a leading cause of disability worldwide. The number of people living with this disease varies in different countries ranging from about 10% to 20%.start superscript, 1, end superscript The likelihood of you having osteoarthritis increase with age, and it is most common among people in their late sixties and early seventies.start superscript, 1, end superscript In general, osteoarthritis is more prevalent in Europe and the USA than in in other parts of the world. Rheumatoid arthritis is about one tenth as common as osteoarthritis, affecting about 1% of people.squared There’s a higher prevalence in some countries than others, and even between regions within the same country.This may be due to genetic or environmental factors, as well as to autoimmune diseases generally being more common in developed countries.
In both cases, the higher incidence of arthritis in western countries is likely due, at least in part, to under-reporting in low-income countries where people tend to have less access to health care.

Can arthritis be prevented?

There are some thing you can do that may help prevent or slow the development of osteoarthritis, so it is important to know the warning signs - pain, stiffness and possibly swelling, and difficulty moving a joint. Visiting your doctor and getting treatment early can help minimize pain and inflammation and help you find the right balance of exercise that best protects your joints in the long term. Steps you can take that may help prevent or manage osteoarthritis include:
  • Losing some weight
    • if you are over your recommended weight, try to lose a bit; extra weight puts a lot of extra stress on your joints.
  • Staying active
    • moderate exercise can help increase your range of motion, and the strength and endurance of your muscles, which helps keep your joints more stable.
  • Heat or ice
    • may provide temporary relief of pain and swelling, but make sure to ask for guidance from a healthcare professional first.
  • Protecting your joints
    • adjust your lifestyle to avoid putting your joints under unnecessary stress.
Diagram of ways to prevent arthritis symptoms
Although there is no known way to prevent rheumatoid arthritis, early, aggressive treatment that controls the inflammation may prevent the joint becoming irreversibly damaged. Exercise can reduce pain and bone loss, and quitting smoking may reduce the chances that it happens to you - rheumatoid arthritis is almost twice as high among men who smoke and a bit higher among women smokers compared to non smokers.cubed

What treatments are available for arthritis?

If you are having joint pain and stiffness, your doctor will want to give you a physical exam to assess your affected joints for swelling and tenderness, as well as range of motion. You may also need lab and imaging tests. These are likely to include a blood test for rheumatoid factor, and X-rays. Rheumatoid factor is any one of several autoantibodies (antibodies that attack your own tissue). Testing for this can help your doctor determine whether you have osteoarthritis or rheumatoid arthritis; although, sometimes the test gives a positive result for a different reason, and a negative test result does not necessarily mean you don’t have the disease. X-raying your affected joints may also help with a diagnosis by showing any narrowing of the gap between your bones as well as the growth of bone spurs, or sites of bone erosion.
There is no cure for either of these types of arthritis, but treatments can help reduce pain and inflammation, help maintain range of motion, and reduce joint damage.
Osteoarthritis - acetaminophen is often recommended for helping with mild to moderate osteoarthritic pain, while nonsteroidal anti-inflammatory drugs (NSAIDS) may be useful for helping manage pain with inflammation. Unfortunately, problematic side effects limit the use of NSAIDS if you are over the age of 65, although topical formulations are available that also seem to be effective. Your doctor may also recommend physiotherapy to help strengthen your muscles and stabilize your joints, as well as occupational therapy to help with strategies that minimize joint stress due to day-to-day activities.
Rheumatoid arthritis - The treatment goal for rheumatoid arthritis is to control the disease and send it into remission. Various different types of drugs are available to do this including disease-modifying antirheumatic drugs that may be given in combination with steroids, and if this is not enough, biologic agents - drugs that are designed to block the specific parts of your immune system that drive inflammation - can be added to the mix. All of these drugs contribute to slowing the progress of the disease and help to save your joints from permanent damage. As with osteoarthritis, physio- and occupational therapists can help you with exercises that improve movement, and strategies that make day-to-day tasks easier on your joints.
If the medications don’t work very well for you, or you find you can’t take them because of unpleasant side effects, you may be able to have surgery or other procedures that help manage your physical disability. For osteoarthritis, the options include cortisone shots to help with inflammation, lubrication injections to replace the joint’s natural lubricant, bone realignment, and joint replacement. For rheumatoid arthritis, the main options are all surgical, including joint replacement, tendon repair, and joint fusion.

Consider the following:

  • Obesity is an important risk factor for osteoarthritis. Why do you think that might be? Most obese patients will have knee joint deformities that cause misalignment of the joint, which alters the load distribution on the knee and accelerates cartilage composition and degeneration. The increase in force on the knee and hip joints is probably the primary reason that these joints are more susceptible to osteoarthritis. However, new research is also showing that fat cells may play an important role in regulating bone and cartilage metabolism in joints, and this gets out of balance if you are obese.
  • Biologics are used when other treatments are unable to effectively control inflammation. The high cost of these of these drugs has raised concerns about whether or not they will be available for everyone who needs them. Two recent developments may address these concerns. What do you think they might be? 1) Using aggressive combination treatments including biologics at first to gain good control of inflammation in patients with recent-onset rheumatoid arthritis appears to pave the way for effective maintenance therapy with the cheaper conventional drugs - this approach has been used in the treatment of cancer, and is known as “induction-maintenance” treatment. 2) Dosing-down of biologics in patients with established rheumatoid arthritis appears to continue to provide effective disease control at much lower cost.

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