How common is primary Raynauds Phenomenon? Who gets it?
The prevalence of primary RP is estimated to be 3% to 5% in most studies. Estimates based upon patient questionnaires rather than medical provider diagnosis or fulfillment of strict criteria are higher at 10%. Prevalence is higher in colder climates and among women, younger age groups, and in patients with a family history of the phenomenon. RP commonly develops at a young age. New-onset disease after the age of 60 years is uncommon (prevalence, 0.1%–1%). The female to male ratio ranges from 4:1 to 9:1. Estradiol increases the expression of alpha 2c adrenoreceptors on smooth muscle cells leading to increased cutaneous vasoconstriction (see Question 5 for additional details). This has implications outside of RP as baseline digital blood flow in young females (but not postmenopausal females) is lower than that in males in the general population.
