The widely accepted definition for chronic pain is the pain that lasts for more than 3 - 6 months. Other theories state, that the transition of pain from acute to the chronic phase of about 12 months, is termed as chronic pain. Yet another theory postulates that chronic pain is the pain that lasts for more than 6 months.
A pain that lasts for more than 3 to 6 months is termed as chronic pain. Pain in the affected region can continue for duration longer than this. The pain that is experienced is defined as sharp or dull, with burning or aching sensation, which may either be constant, or occur in between intervals.
In addition to the persistent pain that is experienced, affected individuals also suffer from undue fatigue, decreased appetite and sleep disturbances. Individuals also undergo significant mood changes, which are strong enough to cause suicidal ideation. Chronic pain is also known to significantly disrupt daily activities, and also negatively impacts the quality of life. Patients also report that, chronic pain takes a toll on their relationships and is a major cause of anxiety and depression.
Proper diagnostic procedures need to be employed for determining any underlying disease condition that is causing the pain. In many instances, diagnosis of chronic pain is made based on the symptoms that are reported by the patient. Imaging studies such as MRI of the brain is indicated to study structural changes that take place during chronic pain . Several laboratory studies may also be required to determine the underlying etiology.
Chronic pain can be effectively managed with combination of medications and other therapies. Anti-inflammatory non-steroidal drugs are used for relieving pain. Topical application of these compounds should be considered and is particularly meant for those individuals who are unable to tolerate oral drugs. Individuals suffering from low back pain are given strong opoids. In addition to pain relieving medications, antidepressants should also be given to patients to cope with strong mood fluctuations . Physical therapy in form of exercises forms an integral part of treatment regime and should be religiously followed by all individuals suffering from chronic pain.
Individuals affected by chronic pain experience depression and anxiety. In addition, sleep disturbance and onset of insomnia, is a common occurrence, which are induced by the medications prescribed for relieving the pain. Affected individuals also decrease physical activity, due to inability to work with pain or the fear that pain would increase upon physical exertion. Research has shown that, chronic pain is significantly associated with 10 year mortality .
The following factors can give rise to chronic pain:
In addition to the above mentioned conditions, several risk factors can also increase the risk of developing chronic pain. These include :
Statistics have revealed that, about 116 million Americans suffer from some or other type of chronic pain. Of these, about 63% seek medical advice for chronic pain. The prevalence of chronic pain in the US is estimated to be 30%. Research has pointed towards the fact that, chronic pain utilizes a major share of health care resources. Women are known to be more affected by the condition than men. In an internet based research study, it was revealed that 34.3% women and 26.7% men in the US suffered from chronic pain . A survey carried out in the year 2010, stated that 19% of adult population in US reported to suffer from chronic pain for at least 3 months or more .
Chronic pain is classified as nociceptive and neuropathic. The former type occurs due to activation of nociceptors and the latter occurs due to malfunctioning of the nervous system .
When the nociceptive receptors are constantly activated, there is transmission to the dorsal horn, which may in turn induce “pain wind-up phenomenon”. Such a type of phenomenon creates pathological changes that lower the threshold of pain, along with activation of the nociceptive receptors to respond to the sensation of pain . The nerve fibers that are involved in these series of events are C-fibers, which have a low conductivity, giving rise to sensation of pain that continues over a long period.
It is believed that, several structural changes occur in the brain in response to chronic pain. In addition, grey matter loss also takes place, which is, however, reversible when the pain subsides .
Based on all the theories stating different duration of chronic pain, another popular definition has defined chronic pain, as the one that is experienced and extends beyond the anticipated period of healing. Such type of pain cannot be cured; but can be managed with a proper treatment regime .