Osteoarthritis risk factors
Osteoarthritis risk factors On the Web
American Roentgen Ray Society Images of Osteoarthritis risk factors
Osteoarthritis is a multifactorial disease and the interactions between systemic and local factors play important role in development and prognosis of OA.
I: Systemic risk factors for Osteoarthritis
Knee, hip, and hand osteoarthritis are higher in women than men. It has also been reported that the frequency of osteoarthritis in women and men are 68% and 58% respectively. And it has been reported that women have a greater level of pain and disability.
There are significant differences in the prevalence and the joint involvement patterns of OA between different racial and ethnic groups. The African American women had similar OA of Hip similar to white women. Its been reported that the knee OA in the USA is more common in Blacks than whites. Prevalence of hip OA in among whites in Africa and the Caribbean was higher than blacks. In another study, comparing the prevalence of knee OA between Chinese and whites in the USA, despite the higher rate of obesity among whites, knee OA was higher among Chinese women. The frequencies of hand OA and hip OA in Chinese population is 50% and 10% of the normal population. It can be concluded that the lower risk of hip and hand OA can be due to the genetic factors while the higher prevalence of knee OA can be linked to their squatting and other daily and occupational physical activities, which causes excessive pressure on their knee.
Age plays an important role in the development of osteoarthritis. The correlation between age and the occurrence of OA is complex. Higher age through oxidative damage, thinning of cartilage, muscle weakening, reduces the basic cellular mechanisms that maintain tissue homeostasis which leads to an insufficient response to stress or joint injury, demolition of joint tissue destruction. Higher age leads to decrease in the tensile property of cartilage in articular cartilage in the accumulation of glycation consequently it can cause mechanical failure
It's been showed that genetic factors play important roles in development and even the prognosis of osteoarthritis. genetic factors are leads to osteoarthritis in nearly 70% of cases. Moreover, specific genes such as chromosomes 2, 3, 4, 6, 7, 11, 16, the X. It's been reported that there is a strong correlation between the chromosome 2q13–32 and particular types of OA. For example, chromosomes 4, 6, 7, and 16 (susceptible locus: 4q35, 6p12.3–q13, 7q34-7q36.3, 7p15-7p21, 7q22, and 16p12.3-p12.1, respectively) are linked for hip and hand OA. The previously mentioned locus of chromosome 4 and 7 are also linked to knee OA.
The osteoarthritis of knee, hip, and hand significantly increases around the time of menopause. Because of this, it's been hypothesized that hormonal factors might be involved in the occurrence of OA. Up to this time, there is no report regarding the confirmation regarding the possible correlation between sex hormones and hand, knee, or hip OA in women. Osteocalcin, as a marker of bone turnover, decreases in women after their menopause which consequently women after menopause are more susceptible to knee arthritis.
Dietary related agents have an important roll in OA. Lower vitamin D, vitamin C, and selenium intakes have been associated with an increased risk of progression of knee OA in the older population. Also, using unrefined carbohydrates and junk foods in daily diet increase the chance of chronic diseases. Meanwhile, chondrocytes is an important and powerful origin of reactive oxygen species (ROC). Chondrocytes can damage cartilage collagen and synovial fluid hyaluronate. Meanwhile, micronutrients antioxidants, by providing defense against tissue injuries, are helpful to protect against osteoarthritis.
Smoking is proven to be correlated with an increased risk of cartilage loss and knee pain in OA.
II: Local risk factors for Osteoarthritis
Doing repetitive and excessive joint loading which is common in specific heavy physical activities such as long-distance runners, karate, kung fu, and gymnastic could increase the risk of knee injury and developing OA in involved joints.
Trauma and injury to Joint
The traumatic injuries are known to have a strong association with the development of OA. Acute injuries such as bone fractures and dislocations, meniscal tearing and cruciate tearing, direct damage to local tissues, normal biomechanics disruption, increase the risk of OA development. Articular cartilage bears pressures from daily physical activities. Joints injuries and trauma the cartilage can influence their flexibility, eliminate cellular system and consequently decrease the subchondral loading capability.
Higher body mass index (BMI) is a well-known predictor for risk factors of OA. It's been reported that the correlation between obesity and knee OA is greater than with hip OA. Also, OA is associated with the metabolic syndrome, cardiovascular risk factors such as hypertension and hypercholesterolemia. Although the association between diabetes and OA is contradictory, it has been hypothesized that higher glucose concentrations product ROS and glycation leading to the cartilage degeneration and degradation. Since high BMI and obesity are considered as the major risk factor for OA, it's been found that weight loss improves patient outcomes.
A meta-analysis of weight reduction and knee osteoarthritis concluded that weight loss of 5 percent from baseline was sufficient to reduce disability. Additionally, pain and disability were reduced if patients lost more than 6 kg (13.2 lb). Aerobic exercise is important for weight loss but can be challenging in persons with osteoarthritis of weight-bearing joints. Swimming, elliptical training, cycling, and upper body exercise may help in such cases.
Occupation facing heavy loads and having stress activities such as workers whose jobs require repeated pincer grip and prolonged squatting and kneeling are consequently associated hand OA and knee OA, respectively .
The mechanical alignment of the knee plays an important roll in distributing the pressure through the articular surfaces. In a normal knee, 60-70% of the pressure is transferred through the medial compartment. Any structural problems like valgus or varus influences pressure distribution in joint and this misalignment play an important role in the development and progression of OA.