慢性疼痛
慢性疼痛是种持续很长时间的疼痛。在医学上，急性和慢性疼痛的区分有时是由发作时间来决定的；最常用的两种标记为3个月和6个月后发病[1]， 虽然有些理论家和研究者定义从急性到慢性疼痛为12个月[2]。
但是还有些人认为急性疼痛持续不到30天，慢性疼痛为持续时间超过六个月的疼痛，以及亚急性疼痛是持续一到六个月[3]。 慢性疼痛的另一个比较流行的定义，不涉及固定的持续时间，是痛苦延伸到疼痛愈合前的的预计时间[1] 。
流行病学的研究发现，10.1%至55.2%在不同国家的人有慢性疼痛[4]。 慢性疼痛可能源于身体，或在大脑或脊髓。治疗通常很困难。各种非阿片类药物被首要推荐，取决于疼痛来源于组织损伤还是神经病[5] [6]。
心理治疗包括认知行为治疗和接受与承诺疗法 ，可有效地提高慢性疼痛病人的生活质量。
有些慢性疼痛的病人可能从阿片药物治疗中获益，而另外一些人反而产生伤害[7] [8]。
试用药物只推荐那些没有精神疾病史和物质使用障碍史的没有癌症疼痛的病人，且如果没有效应立即停止[ 9 ]。
严重的慢性疼痛与10年死亡率增加有关，特别是心脏病和呼吸系统疾病。患有慢性疼痛的人往往有较高机率的抑郁、焦虑和睡眠障碍，这是相关的，通常不清楚是什么因素导致另一个因素。慢性疼痛可能会导致身体活动的减少，因为害怕加剧疼痛，常常导致体重增加。疼痛强度、疼痛控制、疼痛的弹性是由一个人所拥有的不同等级和类型的社会支持所影响。
下附原文：
Chronic pain is pain that lasts a long time. In medicine, the distinction between acute and chronic pain is sometimes determined by an arbitrary interval of time since onset; the two most commonly used markers being 3 months and 6 months since onset,[1] though some theorists and researchers have placed the transition from acute to chronic pain at 12 months.[2] Others apply acute to pain that lasts less than 30 days, chronic to pain of more than six months duration, and subacute to pain that lasts from one to six months.[3] A popular alternative definition of chronic pain, involving no arbitrarily fixed duration, is 'pain that extends beyond the expected period of healing'.[1] Epidemiological studies have found that 10.1% to 55.2% of people in various countries have chronic pain.[4]
Chronic pain may originate in the body, or in the brain or spinal cord. It is often difficult to treat. Various nonopioid medicines are recommended initially, depending on whether the pain originates from tissue damage or is neuropathic.[5][6]Psychological treatments including cognitive behavioral therapy and acceptance and commitment therapy may be effective for improving quality of life in those with chronic pain. Some people with chronic pain may benefit from opioid treatment while others are harmed.[7][8] A trial of opioids is only recommended in those with non cancer pain who have no history of either mental illness or substance use disorder and should be stopped if not effective.[9]
Severe chronic pain is associated with increased 10 year mortality, particularly from heart disease and respiratory disease. People with chronic pain tend to have higher rates of depression, anxiety, and sleep disturbances; these are correlations and it is often not clear which factor causes another. Chronic pain may contribute to decreased physical activity due to fear of exacerbating pain, often resulting in weight gain. Pain intensity, pain control, and resiliency to pain are influenced by different levels and types of social support that a person with chronic pain receives.
