Epidemiology of Raynaud’s Phenomenon

The prevalence of Raynaud’s phenomenon (RP) in the general population lies between 3 and 5% in most studies. Primary RP, accounting for 80–90% of cases, is characterised by reversible vasospasm in peripheral arteries without underlying disease. In contrast, secondary RP develops in association with an underlying disorder and often involves structural vascular abnormalities and irreversible vascular occlusion. The prevalence of primary RP ranges from 2 to 20% in women and 1–12% in men depending on geographic location, the population studied, the definition of RP used, and the method of case ascertainment. Primary RP in women typically begins at an early age, with genetics, hormonal factors, and emotional stressors playing a potential aetiologic role. In men, RP is associated with increasing age, smoking, atherosclerotic peripheral vascular disease, and occupational factors including vibration. Cooler climates and low body weight are risk factors in both sexes. The prevalence of secondary RP is related to the underlying disease. Progression to secondary RP occurs in 14–37% of subjects with primary RP. Almost 99% of patients who progress to secondary RP develop an autoimmune disease, most commonly systemic sclerosis. Risk factors for progression include positive ANA, SSc-specific autoantibodies, and abnormal nailfold capillaroscopy. Primary RP follows a relatively benign course with minimal impact on function and quality of life. The greatest impact of secondary RP on morbidity and function arises from the complications of digital ulceration and ischemic necrosis, namely pain, infection, gangrene, and amputation, with resultant loss of hand function.