Functional and symptomatic burden of small fiber neuropathy in sarcoidosis

Sarcoidosis is frequently complicated by loss of unmyelinated small nerve fibers, leading to pain and dysautonomia. The implications of sarcoidosis–associated small fiber neuropathy (SFN) on quality of life and functional status are not well described. We systematically measured medication burden, pain (Brief Pain Inventory), fatigue, quality of life (SF-36) and 6 minute walk distance (6MWD) at baseline in a prospective study of 64 US and Dutch sarcoidosis patients. All patients had SFN confirmed by skin biopsy or corneal confocal microscopy. We assessed neuropathic symptoms using the Neuropathic Pain Symptom Inventory (NPSI). Only 42% of patients had active sarcoidosis requiring steroids or immunosuppressants. The overall symptom burden was high, with reduced SF-36 scores in all domains compared with the Medical Outcomes Study group. NPSI score correlated with fatigue (r=0.38, p<0.01)) and pain metrics as assessed by BPI (r=0.51-66, p<0.001). The mean number of medications for neuropathy was 1.4 ± 1.8. Analgesics, antidepressants, antipsychotic agents, GABA analogues and narcotics were used by 83%, 69%, 50%, 22% and 11% of the cohort, respectively. The mean 6MWD was reduced (457m). By linear regression, age, height and neuropathic symptoms (NPSI, r=0.33, p=0.009) independently predicted 6MWD. These data suggest that SFN in sarcoidosis is associated with substantial impairment of QOL, and is not necessarily present at the same time as active granulomatous i...
Source: European Respiratory Journal - Category: Respiratory Medicine Authors: Tags: Diffuse Parenchymal Lung Disease Source Type: research