Complex regional pain syndrome type 1 predictors - Epidemiological perspective from a national database analysis.

OBJECTIVE: Complex regional pain syndrome type 1 is a disabling pain disorder with unclear etiology. It is usually triggered by an injury to a limb with or without specific nerve injury. The objective of this study is to explore the risk factors and predictors for this disease utilizing a large national database.

DESIGN: Retrospective analysis of the Nationwide Inpatient Sample database from 2007 to 2011 in the United States.

SETTING AND PATIENTS: Adult inpatients diagnosed with complex regional pain syndrome type 1.

STATISTICAL ANALYSIS: Chi-square, simple and multivariate logistic regression analyses were conducted. The regression model was adjusted to the patient's demographics and comorbidities.

MAIN RESULTS: There were 22,533 patients with the discharge diagnosis of complex regional pain syndrome type 1 of an inpatient sample of 33,406,123. It peaks between age 45 and 55. Female gender, Caucasian race, higher median household income, headache, depression, drug abuse and private insurance patients (vs Medicaid patients) were associated with higher rate of complex regional pain syndrome type 1. On the other hand, diabetes, obesity, hypothyroidism, and anemia were associated with a lower rate.

CONCLUSIONS: Utilizing a large database, our study added more information to the risk profile of the complex regional pain syndrome type 1 in an inpatient population. Such information should be useful for physician for early recognition, diagnosis of patients at risk.