Osteoarthritis

Is resistance training related to the risk of arthritis among adults over 50?

Eloy Quesada

3776001

HSA 4700

Literature Review

Arthritis is very common and yet it is not well understood. Arthritis is not a single disease, but instead is an informal way of referring to more than 100 different types of joint pain and/or related conditions (“What is Osteoarthritis?”). Sometimes called degenerative joint disease or degenerative arthritis, osteoarthritis is the most common chronic condition of the joints, affecting approximately 27 million Americans (“What is Osteoarthritis?”). For a long time osteoarthritis was believed to be caused by the “wear and tear” of joints over time, however, scientists now view it to be a disease of the joint (“What

is Osteoarthritis?”). Osteoarthritis can affect any joint, but it occurs most often in the knees, hips, lower back, neck, small joints of the fingers and the bases of the thumb and big toe (“What is Osteoarthritis?”). It has been estimated that about 40% to 80% of people with radiographic changes will have symptomatic knee osteoarthritis which is highly prevalent among older people worldwide, 10% to 30%, especially in rural regions where people are involved in heavy occupational tasks (Olagbegi, Adegoke, & Odole, 2016). The prevalence of osteoarthritis also increases with age and a majority of individuals over the age of 65 have radiographic or clinical evidence of osteoarthritis (Olagbegi et al., 2016). The disease itself may not directly lead to mortality, but it does influence the quality of life of the individual diagnosed with it (Singh, Kalaivani, Krishnan, Aggarwal, & Kumar Gupta, 2014). Presence of osteoarthritis in older adults is associated with more pain, functional limitations, and a lower quality of life (Singh et al., 2014).
Various genetic traits can make a person more likely to develop osteoarthritis (“What is Osteoarthritis?”). One possibility is a rare defect in the body’s production of collagen, which is a protein that makes up cartilage, and can cause osteoarthritis to occur as early as 20 in some individuals (“What is Osteoarthritis?”). Other inherited traits can result in defects in the way bones fit together, which cause cartilage to wear away faster than usual (“What is Osteoarthritis?”). Researchers have found that a gene called FAAH (fatty acid amide hydrolase), previously linked to increased pain sensitivity is higher in people with knee osteoarthritis than in people who don’t have the disease (“What is Osteoarthritis?”).
Another factor that can lead to osteoarthritis is an individual’s body weight.

Being overweight puts additional pressure on joints in the hips and knees. Years of carrying these extra pounds can increase the rate at which the cartilage in the joint breaks down (“What is Osteoarthritis?”). Research has shown there is a link between being overweight and having an increased risk of osteoarthritis in the hands (“What is Osteoarthritis?”). These studies also suggest that excess fat tissue produces inflammatory chemicals, known as cytokines, which consequently can damage the joints (“What is Osteoarthritis?”). Ageing of the population and increased global prevalence of obesity are anticipated to dramatically increase the prevalence of osteoarthritis and other impairments associated with it (Olagbegi et al.,

2016).
Osteoarthritis may also be the result of certain injuries that occur in the affected joint.

Repetitive movements or injuries to joints (such as a fractures, surgery or ligament tears) can lead to the disease (“What is Osteoarthritis?”). For example some athletes, repeatedly damage joints, tendons and ligaments, which can speed up the breakdown of cartilage (“What is Osteoarthritis?”). Certain careers that require standing for long periods of time, repetitive bending, heavy lifting or other movements can also make cartilage wear away more quickly (“What is Osteoarthritis?”). Another factor that has been shown to alter the rate of cartilage breakdown is an imbalance or weakness of the muscles supporting a joint (“What is

Osteoarthritis?”).
As of today there is no known cure for osteoarthritis and it is a major public health issue because it causes chronic pain, reduces physical function and diminishes quality of life (Olagbegi et al., 2016). Although pain is the most common symptom that often makes individuals with osteoarthritis seek medical attention, the patient may have other symptoms like limitation of joint motion, muscle atrophy and weakness, joint instability, progressive functional limitation and associated disability, depending on the severity and stage of the disease (Olagbegi et al., 2016). Ultimately, chronic osteoarthritis of the lower limb joints (like the knees and hips) leads to lower physical fitness, which results in an increased risk of cardio metabolic co-morbidity and early mortality (Olagbegi et al., 2016).
Since there is no cure for the disease the only way to improve quality of life for patients would be to improve the amount of pain the patient is experiencing. It is well known that both endurance and resistance training can substantially improve physical fitness and health related factors in older individuals (Romero-Arenas, Martinez-Pascual, & Alcaraz, 2013). Resistance training has been shown to be effective for increasing basal metabolism, bone mineral density, muscle strength and power, and the cross-sectional area of both muscle and connective tissue (Romero-Arenas et al., 2013). The Ottawa Panel has even recommended land-based therapeutic exercise, notably strength training, for reducing pain, stiffness and self-reported disability and improving physical function and range of motion of the effected joint (Nguyen, Lefevre-Colau, Poiraudeau, & Rannou, 2016). Range of motion means the ability of joints to perform motions before being limited by the structure of the bones, ligaments or the surrounding muscle mass (Kordi, Rafiee, Shirvan, & Darvishi, 2014). Evidence from systematic reviews and meta-analyses of randomized controlled trials have shown that muscle strengthening and aerobic exercises are effective in reducing pain and disability as well as improving the quality of life in patients with mild to moderate osteoarthritis of the knee (Olagbegi et al., 2016). Exercise therapy for these joints should not only improve range of motion, muscle and tendon lengthening, strength, and endurance but should also decrease pain and loading on the symptomatic compartment (Nguyen et al., 2016).
This type of therapy is not only limited to osteoarthritis but can also be used to manage symptoms of other forms of arthritis. Rheumatoid arthritis is a chronic inflammatory autoimmune disease, causing progressive damage to the musculoskeletal system, loss of function and increased energy expenditure (Strasser, Leeb, Strehblow, Schobersberger, Haber, & Cauza, 2011). Patients with rheumatoid arthritis suffer from muscle loss and reduced muscle strength, ranging from 30% to 70%, while endurance is reduced to 50% (Strasser et al., 2011). Long-term training appears to be effective in reducing disease activity and pains (Strasser et al., 2011).
A single blind, randomized, controlled trial was carried out using women with unilateral or bilateral osteoarthritis of the knee, based on the classification criteria of the American College of Rheumatology. The purpose of this trial was to determine the effect of a progressive resistance exercise program on women with osteoarthritis of the knee. Twenty-nine female subjects were randomly assigned to the experimental group and 31 were randomly assigned to the control group. The participants in the experimental group took part in a 12 week resistance program that consisted of strengthening exercises for knee extensors, knee flexors, hip abductors and hip adductors, all performed with 50% and 70% of their individual one-repetition maximum using machines with free weights. Resistance was reevaluated every two weeks and assessments of pain, muscle strength, walking distance, function, and quality of life were performed at the beginning of the trial for a baseline, at 6 weeks, and at 12 weeks at the conclusion of the trial. The results of the trial showed improvements in pain and muscle strength for the experimental group as well as improvements in some domains of quality of life (Jorge, Souza, Chiari, Jones, Fernandes, Junior, & Natour, 2015).
This researcher predicts that resistance training under the right conditions will help reduce the risk of osteoarthritis by strengthening and maintaining the muscles and tendons around the joints. An increase in muscle mass and strength will help reduce the probability of injury along with major imbalances in the joints. Resistance training will also reduce other factors that have been linked to increase the prevalence of osteoarthritis such as weight.