Hypervigilance in the development of chronic pain

慢性疼痛是一种常见的、令人虚弱的疾病。澳大利亚社区中有五分之一的人被发现在任何时候都会经历慢性疼痛。虽然没有证据表明慢性疼痛的发病率持续上升，但近几十年来，永久性伤残率大幅上升。这导致了慢性疼痛的成本不断上升。例如，背部疼痛是提出工人索赔的最常见原因，每年导致1.018亿个工作日的损失。据估计，在美国，仅背部疼痛每年的医疗费用就高达500亿澳元，在澳大利亚则高达100亿美元。慢性疼痛不仅是一个相当大的经济负担，而且对患者来说也是一个相当大的个人负担。疼痛是生活质量差的最强有力的预测因素之一，而且一直被发现与高抑郁发生率有关。尽管有大量的研究调查了哪些因素与慢性疼痛有关，但令人惊讶的是，很少有研究调查导致慢性疼痛的机制。慢性疼痛的理论表明，心理特征增加了人们患慢性疼痛的倾向。具体地说，理论认为，那些倾向于害怕疼痛的人会过度关注疼痛的感觉，避免引发疼痛的活动，因此有发展成慢性疼痛的风险。这项研究将检验这些理论。如果发现过度关注疼痛确实会使患者容易患上慢性疼痛，这将对预防慢性疼痛的发展具有重要意义。这些发现有助于制定预防慢性病的早期干预措施，从而减轻卫生服务的经济负担和患者因生活质量下降而造成的情感负担。

Chronic pain is a common and debilitating condition. One in five people in the Australian community have been found to experience chronic pain at any one time. Although there is no evidence of a consistent increase in rates of chronic pain, the rate of permanent disability has increased dramatically in recent decades. This has contributed to the growing cost of chronic pain. For example, back pain is the most common reason for filing workers' compensation claims and leads to loss of 101.8 million workdays annually. The annual costs of medical care for back pain alone have been estimated at $AUD50 billion in the US and $10 billion in Australia. Not only is chronic pain a considerable economic burden, it is also a considerable personal burden to patients. Pain is one of the strongest predictors of poor quality of life and has consistently been found to be associated with high rates of depression. Although there is a large body of research that investigates what factors are associated with chronic pain, there is surprisingly little research that investigates the mechanisms that cause chronicity. Theories of chronic pain suggest that psychological characteristics increase the propensity for people to develop chronic pain. Specifically, theories argue that those people who tend to be fearful of pain will over-attend to painful sensations and avoid pain-provoking activities and as a result are at risk of developing chronic pain. This study will test those theories. If it is found that over-attending to pain does predispose patients to develop chronic pain, this will have important implications for preventing the development of chronic pain. These findings could help to devise early interventions to prevent chronicity and thereby reduce the economic burden to health services and the emotional burden to patients in terms of reduced quality of life.