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Table 1 Case-control study: characteristics of 70,914 hospitalized patients with pneumonia and 709,140 population controls in Denmark (1997-2009)

From: The impact of statin use on pneumonia risk and outcome: a combined population-based case-control and cohort study

Characteristics at time of hospital admission Pneumonia cases
(n = 70,914)
Population controls
(n = 709,140)
Total
(n = 780,045)
Age, number (percentage)    
   15-39 years 5,140 (7.3) 51,601 (7.3) 56,741 (7.3)
   40-64 years 17,803 (25.1) 178,095 (25.1) 195,898 (25.1)
   65-79 years 26,122 (36.8) 261,046 (36.8) 287,168 (36.8)
   ≥80 years 21,849 (30.8) 218,398 (30.8) 240,247 (30.8)
Sex, number (percentage)    
   Female 33,278 (46.9) 332,780 (46.9) 366,058 (46.9)
   Male 37,636 (53.1) 376,360 (53.1) 413,996 (53.1)
Calendar period, number (percentage)    
   1997-2000 17,754 (25.0) 177,540 (25.0) 195,294 (25.0)
   2001-2004 23,786 (33.5) 237,860 (33.5) 261,646 (33.5)
   2005-2009 29,374 (41.4) 293,740 (41.4) 323,144 (41.4)
Preadmission hospital-diagnosed comorbidities, number (percentage)    
Conditions included in the Charlson index    
   Previous myocardial infarction 6,704 (9.5) 39,573 (5.6) 46,277 (5.9)
   Congestive heart failure 7,457 (10.5) 29,791 (4.2) 37,248 (4.8)
   Peripheral vascular disease 6,100 (8.6) 28,615 (4.0) 34,715 (4.5)
   Cerebrovascular disease 10,672 (15.0) 62,515 (8.8) 73,187 (9.4)
   Dementia 1,581 (2.2) 9,343 (1.3) 10,924 (1.4)
   Hemiplegia 472 (0.7) 1,133 (0.2) 1,605 (0.2)
   Chronic pulmonary disease 14,457 (20.4) 44,225 (6.2) 58,682 (7.5)
   Connective tissue disease 3,759 (5.3) 19,158 (2.7) 22,917 (2.9)
   Peptic ulcer disease 6,198 (8.7) 34,861 (4.9) 41,059 (5.3)
   Mild liver disease 1,299 (1.8) 3,671 (0.5) 4,970 (0.6)
   Moderate to severe liver disease 386 (0.54) 861 (0.12) 1,247 (0.2)
   Diabetes without end-stage organ damage 5,662 (8.0) 28,185 (4.0) 33,847 (4.3)
   Diabetes with end-stage organ damage 2,978 (4.2) 11,478 (1.6) 14,456 (1.9)
   Moderate to severe renal disease 2,714 (3.8) 8,523 (1.2) 11,237 (1.4)
   Solid cancer 10,737 (15.1) 62,092 (8.8) 72,829 (9.3)
   Metastatic solid cancer 2,043 (2.9) 4,174 (0.6) 6,217 (0.8)
   Leukemia 744 (1.0) 1,267 (0.2) 2,011 (0.3)
   Lymphoma 1,307 (1.8) 2,490 (0.4) 3,797 (0.5)
   AIDS 88 (0.1) 87 (0.0) 175 (0.0)
Charlson comorbidity index score    
   Low, 0 26,285 (37.1) 457,185 (64.5) 483,470 (62.0)
   Medium, 1-2 28,627 (40.4) 197,723 (27.9) 226,350 (29.0)
   High, ≥3 16,002 (22.6) 54,232 (7.7) 70,234 (9.0)
Additional comorbidity    
   Alcoholism-related disorders 4,303 (6.1) 13,871 (2.0) 18,174 (2.3)
   Obesity 2,869 (4.1) 12,515 (1.8) 15,384 (2.0)
   Any surgical procedure within 90 days of index date 14,782 (20.8) 40,385 (5.7) 55,167 (7.1)
Preadmission medications within 125 days of index date, unless otherwise indicated    
   Statins, current use 7,223 (10.2) 64,523 (9.1) 71,746 (9.2)
   Statins, former use (>125 days) 1,908 (2.7) 14,102 (2.0) 16,010 (2.1)
   Oral steroids (within 1 year of index date) 13,124 (18.5) 45,763 (6.5) 58,887 (7.6)
   Other immunosuppressive drugs (within 1 year of index date) 1,347 (1.9) 4,789 (0.7) 6,136 (0.8)
Users of inhalation medications    
   Beta2 agonists only 5,514 (7.8) 15,110 (2.1) 20,624 (2.6)
   Corticosteroid therapy only 823 (1.2) 5,463 (0.8) 6,286 (0.8)
   Corticosteroid therapy and beta2 agonists 9,119 (12.9) 25,835 (3.6) 34,954 (4.5)
   Beta blockers 11,988 (16.9) 93,125 (13.1) 105,113 (13.5)
   Low-dose aspirin 12,731 (18.0) 95,825 (13.5) 108,556 (13.9)
   Loop diuretics 17,804 (25.1) 76,134 (10.7) 93,938 (12.0)
   Thiazides 9,432 (13.3) 85,475 (12.0) 94,907 (12.2)
   Angiotensin-converting enzyme inhibitors 9,309 (13.1) 73,417 (10.4) 82,726 (10.6)
   Angiotensin II antagonists 4,598 (6.5) 46,242 (6.5) 50,840 (6.5)
   Digoxin 6,071 (8.6) 32,810 (4.6) 38,881 (5.0)
   Vitamin K antagonist 4,024 (5.7) 22,590 (3.2) 26,614 (3.4)
   Calcium antagonists 10,466 (14.8) 84,077 (11.9) 94,543 (12.1)
   Nitrates 6,384 (9.0) 34,384 (4.9) 40,768 (5.2)
   Antipsychotics 4,902 (6.9) 21,013 (3.0) 25,915 (3.3)
   Non-steroidal anti-inflammatory drugs 12,641 (17.8) 87,279 (12.3) 99,920 (12.8)
   Proton-pump inhibitors 11,469 (16.2) 50,146 (7.1) 61,615 (7.9)
Markers of socioeconomic status, number (percentage)    
Marital status, number (percentage)    
   Married 33,423 (47.1) 376,521 (53.1) 409,944 (52.6)
   Never married 8,957 (12.6) 80,230 (11.3) 89,187 (11.4)
   Divorced or widowed 28,348 (40.0) 250,837 (35.4) 279,185 (35.8)
   Unknown 186 (0.3) 1,552 (0.2) 1,738 (0.2)
   Living with small children 940 (1.3) 7,981 (1.1) 8,921 (1.1)
Urbanization of place of residence, number (percentage)    
   Rural 14,138 (20.0) 143,517 (20.2) 157,655 (20.2)
   Provincial town 37,909 (53.5) 384,034 (54.2) 421,943 (54.1)
   City 18,867 (26.6) 181,589 (25.6) 200,456 (25.7)
Markers of frailty and health awareness, number (percentage)a    
   Receipt of current year's influenza vaccine before index date 9,538 (17.9) 74,873 (14.1) 84,411 (14.4)
   Preventive GP consultations and services 5,863 (11.0) 37,349 (7.0) 43,212 (7.0)
   Social medicine-related GP consultations 15,118 (28.4) 59,686 (11.2) 74,804 (12.8)
   GP conversational therapy 5,124 (9.6) 18,738 (3,5) 23,862 (4.1)
   Application for reimbursement for chronic illness 2,703 (5.1) 5,958 (1.1) 8,661 (1.5)
   Application for reimbursement for terminal illness 274 (0.5) 229 (0.04) 503 (0.1)
   GP diagnosis and treatment of dementia 560 (1.1) 4,046 (0.8) 4,606 (0.8)
  1. aAscertained among 53,160 pneumonia cases who could be matched with 531,600 controls for 2001-2009. GP, general practitioner.