Table 1.
Demographic and Clinical Characteristics of the Sample
| No COPD (n=31) | COPD (n=53) | ||||
|---|---|---|---|---|---|
| Demographics | Mean (SD) | N (%) | Mean (SD) | N (%) | Test Statistic t or X2 (p value) |
| Age (years) | 66.1 (6.6) | 70.3 (6.5) | t = −2.81 (0.007) | ||
| Sex (female) | 14 (45.2) | 22 (41.5) | X2 =0.11 (0.744) | ||
| Years of Education | 14.5 (2.2) | 13.8 (2.2) | t = 1.34 (0.183) | ||
| Estimated Premorbid IQ (WRAT 4 Standard Score)1 | 99.9 (9.3) | 101.7 (5.4) | t = −1.05 (0.297) | ||
| MMSE II Raw Score | 28.5 (1.6) | 27.8 (1.5) | t = 1.98 (0.051) | ||
| MMSE II Raw Score ≤ 23 | 1 (3.2) | 1 (1.9) | |||
| Smoking History (Pack-years) | 37.7 (22.3) | 61.2 (36.4) | t = −3.66 (<.001) | ||
| Years Since Smoking Cessation | 22.9 (13.7) | 14.0 (10.9) | t = 3.30 (0.001) | ||
| Obstructive Sleep Apnea (Yes) | 12 (38.7) | 12 (22.6) | X2 =2.47 (0.116) | ||
| Depression and Anxiety (HADS score)2 | 5.0 (3.4) | 7.3 (5.4) | t = −2.42 (0.018) | ||
| Post-Bronchodilator Spirometry | |||||
| FEV1/FVC (%)3 | 77.9 (5.4) | 51.3 (13.0) | t =13.13 (<.001) | ||
| FEV1 % Predicted4 | 91.8 (18.1) | 51.0 (19.3) | t =9.55 (<.001) | ||
| Severity of Airflow Limitation | |||||
| No COPD (GOLD 0)5 | --- | --- | |||
| Mild to Moderate COPD (GOLD 1-2) | --- | 29 (54.7) | |||
| Severe to Very Severe COPD (GOLD 3-4) | --- | 24 (45.3) | |||
1
WRAT-4: Wide Range Achievement Test – Fourth Edition
2
HADS: Hospital Anxiety and Depression Scale
3
FEV1/FVC: Forced expiratory volume in one second (FEV1) over forced vital capacity (FVC)
4
FEV1 % Predicted: Forced expiratory volume in one second divided by the predicted value times 100
5
GOLD: Global Initiative for Chronic Obstructive Lung Disease