Table 3

Statistical parameters characterizing the results obtained from Kaplan-Meier survival curves. Characterization of Dementia Incidence in the Statin Groups and CV Comparator



Dementia cases
Time to incidence for dementia cases (months)
Time to end of study for non-dementia cases (months)







Drug
Sample size (n)
n
%
Mean
SD
Mean
SD
Model 3: HR for incidence of dementia vs CV (95% CI)

CV
394 739
3359
0.85
19.8
8.0
30.3
8.6

Atorvastatin
53 869
275
0.51
19.5
7.7
23.9
11.6
0.91 (0.80–1.02)
Lovastatin
54 052
439
0.81
19.1
7.9
29.7
8.1
0.95 (0.86–1.05)
Simvastatin
727 128
2647
0.36
19.3
7.8
29.1
8.0
0.46 (0.44–0.48)

CV, cardiovacular.

Column 1, medication group; column 2, sample size; column 3, number of dementia cases recorded during the course of the analytic period; column 4, percentage of dementia cases (calculated by dividing the value in column 3 by that in column 2); columns 5 and 6, number of months between start of the analytic period and incidence of dementia, and standard deviation (SD); columns 7 and 8, number of months between start of the analytic period and point at which subjects not receiving a diagnosis of dementia were censored due to the end of the analytic period, and SD.

Hazard ratio for incidence of dementia based on the results from model 3 (Table 2).

Wolozin et al. BMC Medicine 2007 5:20   doi:10.1186/1741-7015-5-20