Effect of Pre-existing Psychiatric Illness on Home Oxygen Requirement in COPD Patients: A Pilot Study

Abstract

PURPOSE: Our cross-sectional, single center, observational study aimed to investigate if pre-existing psychiatric illness would have any effect on the home O2 requirement in COPD patients. METHODS: All patients at home O2 evaluation clinic over a period of 3 months were included in the study. Patients without PFT, PFT not diagnostic of COPD, with history suggestive of primary restrictive lung disease were excluded. Chart review was done for presence of psychiatric illness (depression, anxiety, PTSD, schizophrenia, alcohol abuse); home O2 requirement at rest & exertion; and confounding factors for home O2 requirement (CHF, ILD, pulmonary hypertension). Data was then analyzed by ANOVA. RESULTS: Total of 77 patients were included in analysis. 32 patients were found to have psychiatric illness and required home O2, 30 patients did not have any psychiatric illness and required home O2, 12 patients had psychiatric illness and did not require home O2 and 3 patients did not have psychiatric illness and did not require home O2. FEV1 in these groups was 45.90 +/-18.15, 52.99 +/-21.61, 58.38 +/-17.44 and 73.63 +/-12.91 respectively. There is a statistically significant difference in FEV1 levels between individuals receiving oxygen (either at rest or on exercising) and whether or not they have any psychiatric disorder (F3, 73=2.751; p=0.049). CONCLUSIONS: Presence of pre-existing psychiatric illness significantly delayes the initiation of home O2 therapy, which is the only therapy in COPD with mortality benefit. FEV1 is not the only factor deciding initiation of home O2, but lack of other objective measures makes it difficult to quantify the severity of disease.