Within-person changes in acute chest syndrome (ACS) incidence according to patient age (for SS patients with at least 6 years of follow-up).
| . | . | Mean Incidence (Events/Pt-Yrs) . | Change in Incidence* . | ||
|---|---|---|---|---|---|
| Age at Study Entry (y) . | Sample Size . | First 3 yr . | Second 3 yr . | Mean . | P** . |
| * Incidence rate changes were obtained by subtracting a patient’s rate during the first 3 years of follow-up from his/her rate during the remainder of the follow-up period. | |||||
| ** Paired t- test (probability that the mean change is 0) | |||||
| Table reprinted with permission from Castro O et al. The acute chest syndrome in sickle cell disease: incidence and risk factors. Blood. 1994;84:643-9. | |||||
| 0-4 | 327 | 0.25 | 0.20 | -0.05 | .04 |
| 5-9 | 226 | 0.20 | 0.12 | -0.08 | .0004 |
| 10-14 | 200 | 0.10 | 0.10 | -0.01 | .81 |
| 15-19 | 168 | 0.07 | 0.10 | 0.03 | .08 |
| 20-24 | 140 | 0.14 | 0.14 | 0.0 | .99 |
| 25-29 | 108 | 0.09 | 0.10 | 0.02 | .53 |
| . | . | Mean Incidence (Events/Pt-Yrs) . | Change in Incidence* . | ||
|---|---|---|---|---|---|
| Age at Study Entry (y) . | Sample Size . | First 3 yr . | Second 3 yr . | Mean . | P** . |
| * Incidence rate changes were obtained by subtracting a patient’s rate during the first 3 years of follow-up from his/her rate during the remainder of the follow-up period. | |||||
| ** Paired t- test (probability that the mean change is 0) | |||||
| Table reprinted with permission from Castro O et al. The acute chest syndrome in sickle cell disease: incidence and risk factors. Blood. 1994;84:643-9. | |||||
| 0-4 | 327 | 0.25 | 0.20 | -0.05 | .04 |
| 5-9 | 226 | 0.20 | 0.12 | -0.08 | .0004 |
| 10-14 | 200 | 0.10 | 0.10 | -0.01 | .81 |
| 15-19 | 168 | 0.07 | 0.10 | 0.03 | .08 |
| 20-24 | 140 | 0.14 | 0.14 | 0.0 | .99 |
| 25-29 | 108 | 0.09 | 0.10 | 0.02 | .53 |