Engel-Nitz et al Table 1 Demographic characteristics Stroke cohort New stroke Recurrent Control cohort (N = 2180) (N = 1808) stroke (N = 372) (N = 6540) Days of observation, 571 ± 433* 587 ± 432 489 ± 429 900 ± 446 mean ± sD Pre-index costs, $8085 ± $17,340* $7014 ± $16,054 $13,293 ± $21,860 $3142 ± $7264 mean ± sD Age, mean ± sD 59 ± 13 59 ± 13 60 ± 13 59 ± 13 Age group, n (%) 18–24 13 (0.6) 12 (0.7) 1 (0.3) 39 (0.6) 25–34 51 (2.3) 42 (2.3) 9 (2.4) 153 (2.3) 35–44 190 (8.7) 159 (8.8) 31 (8.3) 570 (8.7) 45–54 513 (23.5) 433 (24.0) 80 (21.5) 1539 (23.5) 55–64 794 (36.4) 665 (36.8) 129 (34.7) 2382 (36.4) 65+ 619 (28.4) 497 (27.5) 122 (32.8) 1857 (28.4) sex, n (%) Female 905 (41.5) 740 (40.9) 165 (44.35) 2715 (41.5) Male 1275 (58.5) 1068 (59.1) 207 (55.65) 3825 (58.5) Region, n (%) Northeast 220 (10.1) 185 (10.2) 35 (9.41) 659 (10.1) Midwest 902 (41.4) 748 (41.4) 154 (41.40) 2705 (41.4) south 880 (40.4) 724 (40.0) 156 (41.94) 2641 (40.4) West 178 (8.2) 151 (8.4) 27 (7.26) 535 (8.2) comorbid illness, n (%) Hypertension 1179 (54.1)* 908 (50.2) 271 (72.9) 1838 (28.1) Diabetes 602 (27.6)* 481 (26.6) 121 (32.5) 654 (10.0) TiA 196 (9.0)* 83 (4.6) 113 (30.3) 62 (1.0) cOPD 189 (8.7)* 134 (7.4) 55 (14.8) 250 (3.8) cHF 138 (6.3)* 84 (4.7) 54 (14.5) 160 (2.5) Mi 54 (2.5)* 26 (1.4) 28 (7.5) 42 (0.6) Notes: All comparisons are relative to the control cohort and are computed by t-test for continuous measures or χ2 test for dichotomous or ordinal measures. *P , 0.001. Abbreviations: cHF, congestive heart failure; cOPD, chronic obstructive pulmonary disease; Mi, myocardial infarction; TiA, transient ischemic attack. Dovepress Length of follow-up varied widely between the cohorts. Controls had the longest average follow-up available with 900 (SD 446) days compared with 571 (SD 433) days for the stroke cohort (P , 0.001). Within the stroke cohort, new stroke patients averaged 587 (SD 432) days of follow-up, and recurrent stroke patients averaged 489 (SD 429) days of follow-up. The stroke cohort was significantly more likely to have pre-existing comorbid disease compared with the control cohort. Hypertension was common, present in 54.1% of stroke patients, compared with 28.10% of control patients (P , 0.001). Diabetes was also highly prevalent, identified in 27.6% of stroke patients compared with 10.0% of controls (P , 0.001). All comorbid conditions were more prevalent in recurrent stroke patients compared with new stroke patients. Unadjusted analysis Stroke patients had a significantly higher rate of incident hospitalization during follow-up compared with controls. A total of 752 (34.5%) stroke patients were hospitalized in follow-up for a rate of 307 incident hospitalizations 908 submit your manuscript | www.dovepress.com Dovepress per 1000 patient-years. Comparatively, 21.2% of control patients were hospitalized at a rate of 100 per 1000 patient- years. Patients with recurrent stroke had the highest rate of hospitalization (382 incident hospitalizations per 1000 patient-years) compared with new stroke patients, who had 294 incident hospitalizations per 1000 patient-years. A total of 340 stroke patients (15.6%) experienced a sub- sequent stroke following index hospital discharge for an incident rate of 115 strokes per 1000 patient-years. This was a substantially higher rate compared with the control patients (5 strokes per 1000 patient-years). The rate of fatal stroke was 6 per 1000 patient-years for all stroke patients compared with ,1 for control subjects. Among recurrent stroke patients, additional stroke had an incident rate of 165 per 1000 patient-years, whereas fatal strokes had an incident rate of 8 per 1000 patient-years. New stroke patients were comparatively less likely to experience an additional stroke (107 strokes and 5 fatal strokes per 1000 patient-years). The incidence of post-index date TIA was higher among stroke patients than that in controls (186 incident TIA Vascular Health and Risk Management 2010:6