Table 3.
Adjusted association between psychological status and health-related quality of life (SGRQ).
| Total | Activity | Impact | Symptoms | |||||
|---|---|---|---|---|---|---|---|---|
| β (95% CI)* | p value | β (95% CI)* | p value | β (95% CI)* | p value | β (95% CI)* | p value | |
| Psychological factors: | ||||||||
| Anxiety only | 6.02 (2.88, 9.16) | < 0.001 | 4.23 (-0.07, 8.52) | 0.054 | 8.71 (4.93, 12.49) | < 0.001 | 4.07 (-0.42, 8.56) | 0.076 |
| Depression only | 6.29 (0.55, 12.03) | 0.032 | 11.34 (2.92, 19.77) | 0.008 | 5.90 (-1.03, 12.82) | 0.095 | 4.25 (-3.85, 12.34) | 0.303 |
| Anxiety and depression | 17.06 (12.50, 21.62) | < 0.001 | 17.73 (11.24, 24.22) | < 0.001 | 18.35 (12.79, 23.91) | < 0.001 | 11.49 (5.36, 17.62) | < 0.001 |
| Gender: females | - | - | -7.84 (-14.67, -1.01) | 0.025 | - | - | - | - |
| Working status: current workers | - | - | - | - | - | - | 8.03 (3.43, 12.64) | 0.001 |
| ATS/ERS severity stages: | ||||||||
| Mild | reference | reference | reference | |||||
| Moderate | 5.25 (-0.09, 10.58) | 0.054 | 5.72 (-1.58, 13.01) | 0.124 | 7.34 (0.91, 13.77) | 0.025 | - | - |
| Severe | 11.25 (5.73, 16.76) | < 0.001 | 14.49 (6.89, 22.09) | < 0.001 | 12.93 (6.28, 19.57) | < 0.001 | ||
| Very severe | 16.84 (9.78, 23.90) | < 0.001 | 18.25 (8.35, 28.14) | < 0.001 | 18.51 (9.92, 27.10) | < 0.001 | ||
| 6MWD (m) | - | - | -0.02 (-0.04, -0.00) | 0.033 | - | - | - | - |
| Dyspnea (score from 0 to 5) | 6.87 (5.90, 7.85) | < 0.001 | 9.87 (8.46, 11.28) | < 0.001 | 5.54 (4.37, 6.72) | < 0.001 | 4.36 (3.09, 5.64) | < 0.001 |
| BMI: <20 (kg/m2) | - | - | - | - | 9.93 (0.90, 18.96) | 0.031 | - | - |
| Barthel Index: dependent† | 6.67 (2.18, 11.15) | 0.003 | 10.73 (3.14, 18.31) | 0.006 | 5.76 (0.35, 11.17) | 0.037 | - | - |
| Charlson Comorbidities: ≥2 | 3.70 (1.26, 6.15) | 0.003 | 4.94 (1.53, 8.35) | 0.005 | 3.91 (0.96, 6.86) | 0.010 | - | - |
| Adjusted R2 | 0.61 | 0.65 | 0.49 | 0.20 | ||||
CI: confidence interval
* Each column is a single multivariate lineal regression model including as covariates the variables that show a coefficient in each column. Beta-coefficients are expressed in points of the SGRQ score per (i) each unit of the continuous covariates in the model, or (ii) a change with respect to reference category in categorical covariates.
† Dependent defined as Barthel Index < 100
Age, socioeconomic status, level of education, marital status, smoking status, DLco, RV/TLC, PaO2 and PaCO2, were tested as potential confounders and finally not included because they were not independently related to the outcome, nor modified estimates for the remaining variables.