How postmenopausal osteoporosis influences epidemiology and clinical features of CRPS-1

This study aimed to investigate the relationship between Osteoporosis (OP) and Complex Regional Pain Syndrome type 1 (CRPS-1), in the hypothesis that OP can influence the epidemiological and clinical features of CRPS-1.

From March 2013 to May 2024, consecutive patients newly diagnosed with CRPS-1 were recruited. Demographic and clinical variables were collected in a standardised fashion. Univariate analyses and multivariate linear regression models were used to investigate the sample.

We enrolled 425 patients, mostly females (70.1%), more than half (52.2%) with a fracture as the inciting event. A previous OP diagnosis was found in 113 patients (26.6%). Variables significantly associated with OP were female gender, hand localisation, fracture as the inciting event, and a more severe CRPS-1. A fracture in patients with OP seems to trigger CRPS-1 mainly in women in the first decade after menopause, while in males and in older women a weaker association was observed. Multivariate analysis showed a correlation between OP and a more severe CRPS-1 (p = 0.014).

A higher incidence of OP was observed more frequently in women with CRPS-1 in the first decade after menopause. This result could be driven by the proinflammatory cytokines increase observed in the early menopause, inducing both a faster systemic bone loss and an "inflammatory milieu" acting as a predisposing factor for CRPS-1 onset and a more severe disease.