RATIONALE: Subjective cognitive difficulties are common among sarcoidosis patients; however, previous studies have not modeled the link between cognitive difficulties and health-related quality of life (HRQOL).
OBJECTIVES: To determine whether cognitive difficulties are associated with HRQOL in sarcoidosis patients after adjusting for demographics, fatigue, and physical disease severity measures.
METHODS: We performed a secondary analysis of the Genomic Research in Alpha-1 antitrypsin Deficiency and Sarcoidosis (GRADS) study data. We examined the association between self-reported cognitive difficulties (Cognitive Failures Questionnaire (CFQ)) and HRQOL (SF12v2 mental and physical component scores) while adjusting for the demographics, fatigue, and physical disease severity measures (i.e., organ involvement, forced vital capacity).
RESULTS: Approximately one-fourth of the patients with sarcoidosis endorsed cognitive difficulties. More frequent cognitive difficulties and more severe fatigue were significantly associated with worse mental HRQOL in the fully adjusted model, while older age was associated with better mental HRQOL. The association between cognitive difficulties and physical HRQOL was not significant in the final model. More severe fatigue, joint involvement, and reduced forced vital capacity (FVC) were associated with worse physical HRQOL, while higher income and higher education were associated with better physical HRQOL.
CONCLUSIONS: Perceived cognitive difficulties are associated with diminished HRQOL after adjusting for demographics, organ involvement, pulmonary function, and fatigue. The association between cognitive difficulties and reduced HRQOL primarily occurs through the impact on mental components of HRQOL.