Table 1.
Patient characteristics in the different datasets
| Primary dataset N = 636 |
Primary dataset patients not linked N = 100 |
Linked dataset N = 536 |
Claims dataset N = 74,916 |
||
|---|---|---|---|---|---|
| Based on primary data | Based on primary data | Based on primary data | Based on claims data | Based on claims data | |
| Age, years | |||||
| Mean (SD) | 68.1 (10.1) | 68.6 (11.0) | 68.0 (9.9) | 68.5a (9.9) | 70.9 (11.7) |
| Median (IQR) | 69 (15) | 70 (16) | 69 (15) | 69 (14) | 73 (18) |
| Female gender, n (%) | 242 (38.1) | 47 (47.0) | 195 (36.4) | 195 (36.4) | 34,448 (46.0) |
| Smoking, n (%) | |||||
| Smoker | 218 (34.3) | 32 (32.0) | 186 (34.7) | 247 (46.1) | 16,076 (21.5) |
| Former smoker | 400 (62.9) | 67 (67.0) | 333 (62.1) | ||
| Non-smoker | 17 (2.7) | 1 (1.0) | 16 (3.0) | ||
| Not-specified | 1 (0.2) | 0 (0.0) | 1 (0.2) | ||
| Comorbidities, n (%)b | |||||
| Hypertension | 287 (45.1) | 44 (44.0) | 243 (45.3) | 450 (84.0) | 59,153 (79.0) |
| Diabetes (Type 1 or 2) | 143 (22.5) | 24 (24.0) | 119 (22.2) | 189 (35.3) | 27,905 (37.2) |
| Depression | 48 (7.6) | 12 (12.0) | 36 (6.7) | 157 (29.3) | 17,647 (23.6) |
| Osteoporosis | 50 (7.9) | 7 (7.0) | 43 (8.0) | 99 (18.5) | 12,364 (16.5) |
| FEV1, Lc | |||||
| Mean (SD) | 1.50 (0.6) | 1.56 (0.7) | 1.50 (0.6) | NA | NA |
| Median (IQR) | 1.4 (0.8) | 1.4 (0.9) | 1.4 (0.8) | ||
| % of predicted FEV1d | |||||
| Mean (SD) | 55.6 (17.4) | 57.2 (18.2) | 55.3 (17.2) | NA | NA |
| Median (IQR) | 57.0 (25.3) | 60.0 (26.4) | 56.0 (25.8) | ||
COPD chronic obstructive pulmonary disease, FEV1 forced expiratory volume in 1 s, ICD-10, International Classification of Disease, 10th Edition, IQR interquartile range, SD standard deviation
Primary dataset: all data reported for index date except comorbidities (any known to study physician). Claims dataset: all data reported for date of first COPD diagnosis except comorbidities (from January 2010 to date of first COPD diagnosis). Linked dataset: all data reported for linked dataset index date except comorbidities (primary: any known to study physician; claims: from January 2010 to linked dataset index date)
Smoking status was identified in the claims data using ICD-10 code F17. Comorbidities were selected based on those most commonly reported which could be directly compared between primary and claims data using ICD-10 codes: diabetes: E10/E11; depression: F32/F33; osteoporosis: M80-M82; hypertension: I10-I15
aIn the claims data, only birth year was available. Therefore, age at linked dataset index date was calculated based on the assumption that all patients were born on July 1 of the respective year
bValues were calculated for all patients for whom data were available (primary sample/linked sample): diabetes: 621/518; depression: 611/515; osteoporosis: 561/477; hypertension: 600/512
cValues were calculated for all patients for whom data were available (primary sample: n = 620; linked sample: n = 527)
dValues were calculated for all patients for whom data were available (primary sample: n = 612; linked sample: n = 522)