Background and aims
To estimate the prevalence of pure central (CNP) and peripheral neuropathic pain (PNP) among patients attending pain clinics in Spain. To analyse factors associated with pain intensity and QoL.
Methods
Cross-sectional study involving most of the pain clinics in Spain was carried out, 53 patients with pure CNP and 281 with pure PNP were included. Pain specialists used the revised grading system proposed in 2008 to decide definite, probable or possible diagnostic of NP. 
Results
The prevalence of CNP was 2.4% (CI95%:1.7;3.1) and 12.9% (CI95%:1.5;14.3) of PNP patients. Both group of patients had a high frequency of co-morbid anxiety, depression or sleep disorders, being higher in CNP patients (51.1 %, 71.4%, 71.4%, respectively).
Definite CNP was more likely in patients with lower limbs pain location. In PNP patients, definite diagnostic was more frequent in upper limbs pain location. 
Pain intensity in PNP patients was associated with the presence of depression and sleep disturbances, however, in CNP patients, was related to lower limbs pain location. 
The impairment of QoL was greater in CNP patients than PNP patients, being pain location, presence of depression and sleep disturbance the factors most negatively affecting QoL. Among PNP patients, women and those with higher pain intensity had worse QoL, however, older age and diagnostic certainty were positively related to QoL.
Conclusions
Pain intensity and QoL are affected by different factors in patients suffering central or peripheral neuropathic pain. Identifying these factors could serve to guide therapeutic strategies and improve QoL of patients.

PREVALENCE OF CENTRAL AND PERIPHERAL NEUROPATHIC PAIN AND IMPACT OF DEPRESSION, ANXIETY AND SLEEP DISORDERS ON THE INTENSITY OF PAIN AND QUALITY OF LIFE