Seasonal Variation in Rheumatoid Arthritis

Original Editor - Jenis Bhalavat Top Contributors - Jenis Bhalavat, Reem Ramadan, Mariam Hashem, Kim Jackson, Leana Louw and Lauren Lopez

Introduction

Rheumatoid arthritis (RA) is a chronic, immuno-inflammatory disease that involves the immune system attacking its own tissues. It mainly affects the lining of the hand, wrist, and knee joints. This causes pain, swelling, stiffness, deformity and unsteadiness at the level of the joint. The cause of rheumatoid arthritis is unknown however, it is thought to be triggered by smoking, genes, and infections. Although cold weather does not cause arthritis, RA patients tend to complain of an exacerbation of pain and ache during the winter season.

Influence of Seasonal Parameters on Joints

The seasonal parameters - atmospheric pressure, temperature and humidity have known to cause a flare-up in RA or trigger the disease.

Atmospheric Pressure

It's the force exerted by the atmosphere at a given point and is measured by a barometer. It varies at different altitudes from sea level. The atmospheric pressure changes with change in seasons. There are various theories that try to explain the relationship between the atmospheric pressure and pain experienced in RA patients. One theory states that the wearing off of the cartilage that occurs with arthritis exposes the nerves which pick up pressure causing pain. Another theory states that when atmospheric pressure decreases in winter, the muscles and tendons expand and contract placing more pressure on the nerves leading to pain. A third theory states that the joint fluid in winter or in cold weather tends to become thicker due to change in hydrostatic pressure a a result of change in barometric pressure and leads to further stiffness in the joint and thus leads to more pain and decrease in joint range of motion. Based on a clinical trial study conducted on 200 participants, results showed that the severity of pain experienced by arthritis patients is modestly associated with weather and colder temperature is associated with greater pain.

Humidity

High humidity levels cause sweating and dehydration which lead to blood thickening due to the loss of blood volume which is the blood circulating through body. This leads to an increase in blood pressure forcing the body to put in more work in order to pump blood which eventually lead to a decrease in the concentration of fluid around the joint causing increased friction between the joints, inflammation and joint pain. According to a study that included 1811 RA patients, every 10 mg/L increase in C-reactive protein, a protein made by the liver that indicates the presence of an inflammation, was associated with a 0.38 mmHg reduction in systolic blood pressure. In addition to that, according to another study conducted on patients with different pain conditions predominantly arthritis, the occurrence of a painful event was 12% higher with an increase in humidity compared to a decrease in atmospheric pressure (4%) and higher wind speed (4%). The classic opinion, "Cold and wet is bad, warm and dry is good for RA patients," seems to be true only as far as humidity is concerned.

Temperature

When the temperature drops, our body tends to try and conserve heat by the constriction of blood vessels leading to joint pain and stiffness. This occurs due to the effect temperature has on our muscles and soft tissues causing them to become stiffer to aid in vasoconstriction. Low temperatures may also increase the thickness of joint fluids, making them stiffer and more sensitive to pain during movement. According to a study, patients with RA whose age ranges between 50 to 65 years old were most likely to report a flare with a drop in temperature. Also, a change in season causes a rise in level of IgG antibodies (Rheumatoid factor), thereby triggering the RA inflammatory mechanism in the body. Based on another study, results showed that there was a significant association between low temperature and admission for RA where the tendency to go to the hospital differed between age groups, those below the age of 65 and those above the age of 65, and the risk of admission for RA during cold weather was higher for females compared to males. Also, according to the Arthritis Foundation who published a study from Tufts University in 2007 found that every 10-degree drop in temperature corresponded with an incremental increase in arthritis pain.

Role of Physiotherapy

The main goals of physical therapy when it comes to rheumatoid arthritis involve pain relief, preventing joint damage and functional loss, and reducing functional impairment in daily living activities. As physiotherapist have a long term follow up with RA patients, they can document the seasonal parameters using various weather apps during which the patient experiences pain. Depending on these records, the therapist can predict when will there be a next trigger of RA pain and pre-plan the treatment. One therapeutic modality that can be used is electrostimulation specifically TENS, transcutaneous electrical nerve stimulation, which would aid in relieving pain with analgesia persisting for 18 hours when high frequencies are applied. Similarly, the application of Interferential Current Therapy also aided in relieving pain, swelling and improving range of motion. Another modality would be massage which aids in diminishing swelling at the joint and releasing muscle surrounding the painful joints where studies have showed that the use of manual massage have decreased pain threshold in RA patients. Also, wearing compression gloves aids not only in keeping the patient warm but also aids in pain relief by reducing joint swelling. In addition to that, exercise therapy is very beneficial because muscle weakness can occur due to RA however prior to implementation of the exercise program several characteristics should be taken into consideration including whether the involvement of the joints is local or systemic, stage of the disease, age of the patient, and compliance of the patient with the therapy. The patient can be recommended various exercises before the onset of RA reducing the pain and stiffness. For example the patient might experience pain whenever the pressure is 1002 mbar, humidity at 17% and temperature 41 degrees, so we can alert the patient whenever these conditions are reached to take preventative measures. In the case of acutely inflamed joints, isometric exercises are done and should not be done beyond 40% of maximum voluntary contraction because they may lead to impairment in blood circulation and fatigue after the exercise and patients with active arthritis should particularly avoid activities such as climbing stairs or weight lifting and excessive stress over the tendons during the stretching exercises should also be avoided. In chronic conditions with inactive arthritis, conditioning exercises such as swimming, walking, and cycling with adequate resting periods are recommended for they increase muscle endurance and aerobic capacity and improve functional capabilities of the patient. Furthermore, the use of pneumatic pressure pumps have been found useful in reducing pain and swelling during seasonal flare up. Alternatively the patient can be asked to change the location whenever the weather conditions turn unfavorable.