ITP survival analysis:   nordihydroguaiaretic acid

Intervention:   nordihydroguaiaretic acid     antioxidant, anti-aging
Trial code: NDGA_lo Dose: 800 ppm initiated at age: 6 mo Sex: m Cohort: C2010
Trial code: NDGA_mid Dose: 2500 ppm initiated at age: 6 mo Sex: m Cohort: C2010
Trial code: NDGA_hi Dose: 5000 ppm initiated at age: 6 mo Sex: both Cohort: C2010
This compound had a significant effect on survival:   800 ppm males p = 0.0228; 2500 ppm males p = 0.0147; 5000 ppm males p = 0.0028

Results are based on the use of pooled factor(s) that is/are stratified within the survival analysis model.

All test sites combined – female
NDGA_hi effect on survival, females, test site = All
Log-rank test chisq = 0.6604 p = 0.4164
Wang-Allison test odds ratio = 0.7824 p = 0.5938
Quantiles NDGA_hi Control % difference
25% died before day: 750 786 -5 %
Median lifespan (days) 862 896 -4 %
75% died before day: 998 1034 -3 %
90% died before day: 1106 1116 -1 %
Max lifespan observed (days) 1371 1298
Number of mice at start 125 264
Animal censor events are denoted by + marks in the plot
All test sites combined – male
NDGA_lo effect on survival, males, test site = All
Log-rank test chisq = 5.1834 p = 0.0228
Wang-Allison test odds ratio = 0.9231 p = 0.8639
Quantiles NDGA_lo Control % difference
25% died before day: 650 586 +11 %
Median lifespan (days) 846 777 +9 %
75% died before day: 1018 953 +7 %
90% died before day: 1103 1090 +1 %
Max lifespan observed (days) 1316 1309
Number of mice at start 132 274
Animal censor events are denoted by + marks in the plot
NDGA_mid effect on survival, males, test site = All
Log-rank test chisq = 5.9527 p = 0.0147
Wang-Allison test odds ratio = 0.8814 p = 0.8637
Quantiles NDGA_mid Control % difference
25% died before day: 727 586 +24 %
Median lifespan (days) 868 777 +12 %
75% died before day: 1000 953 +5 %
90% died before day: 1095 1090 0 %
Max lifespan observed (days) 1373 1309
Number of mice at start 133 274
Animal censor events are denoted by + marks in the plot
NDGA_hi effect on survival, males, test site = All
Log-rank test chisq = 8.9645 p = 0.0028
Wang-Allison test odds ratio = 1.7547 p = 0.0874
Quantiles NDGA_hi Control % difference
25% died before day: 719 586 +23 %
Median lifespan (days) 834 777 +7 %
75% died before day: 987 953 +4 %
90% died before day: 1110 1090 +2 %
Max lifespan observed (days) 1282 1309
Number of mice at start 137 274
Animal censor events are denoted by + marks in the plot


By individual test site:

TJL – female
TJL – female      
NDGA_hi effect on survival, females, test site = TJL
Log-rank test chisq = 0.0203 p = 0.8866
Wang-Allison test odds ratio = 1.1808 p = 0.7697
Quantiles NDGA_hi Control % difference
25% died before day: 726 774 -6 %
Median lifespan (days) 859 864 -1 %
75% died before day: 990 993 0 %
90% died before day: 1106 1102 0 %
Max lifespan observed (days) 1278 1222
Number of mice at start 44 92
Animal censor events are denoted by + marks in the plot
TJL – male
TJL – male      
NDGA_lo effect on survival, males, test site = TJL
Log-rank test chisq = 0.8237 p = 0.3641
Wang-Allison test odds ratio = 0.3955 p = 0.342
Quantiles NDGA_lo Control % difference
25% died before day: 599 498 +20 %
Median lifespan (days) 731 683 +7 %
75% died before day: 904 819 +10 %
90% died before day: 999 1067 -6 %
Max lifespan observed (days) 1057 1309
Number of mice at start 39 91
Animal censor events are denoted by + marks in the plot
NDGA_mid effect on survival, males, test site = TJL
Log-rank test chisq = 3.0602 p = 0.0802
Wang-Allison test odds ratio = 0.5617 p = 0.5471
Quantiles NDGA_mid Control % difference
25% died before day: 616 498 +24 %
Median lifespan (days) 794 683 +16 %
75% died before day: 881 819 +8 %
90% died before day: 1034 1067 -3 %
Max lifespan observed (days) 1181 1309
Number of mice at start 42 91
Animal censor events are denoted by + marks in the plot
NDGA_hi effect on survival, males, test site = TJL
Log-rank test chisq = 3.2358 p = 0.072
Wang-Allison test odds ratio = 0.5217 p = 0.3865
Quantiles NDGA_hi Control % difference
25% died before day: 672 498 +35 %
Median lifespan (days) 812 683 +19 %
75% died before day: 918 819 +12 %
90% died before day: 1020 1067 -4 %
Max lifespan observed (days) 1110 1309
Number of mice at start 45 91
Animal censor events are denoted by + marks in the plot
UM – female
UM – female      
NDGA_hi effect on survival, females, test site = UM
Log-rank test chisq = 0.2661 p = 0.6059
Wang-Allison test odds ratio = 0.9493 p = 1.0
Quantiles NDGA_hi Control % difference
25% died before day: 814 811 0 %
Median lifespan (days) 947 930 +2 %
75% died before day: 1043 1064 -2 %
90% died before day: 1122 1132 -1 %
Max lifespan observed (days) 1371 1255
Number of mice at start 41 88
Animal censor events are denoted by + marks in the plot
UM – male
UM – male      
NDGA_lo effect on survival, males, test site = UM
Log-rank test chisq = 1.2431 p = 0.2649
Wang-Allison test odds ratio = 1.0699 p = 1.0
Quantiles NDGA_lo Control % difference
25% died before day: 845 794 +6 %
Median lifespan (days) 992 926 +7 %
75% died before day: 1083 1050 +3 %
90% died before day: 1164 1146 +2 %
Max lifespan observed (days) 1316 1294
Number of mice at start 46 88
Animal censor events are denoted by + marks in the plot
NDGA_mid effect on survival, males, test site = UM
Log-rank test chisq = 0.1389 p = 0.7094
Wang-Allison test odds ratio = 0.7814 p = 0.7734
Quantiles NDGA_mid Control % difference
25% died before day: 824 794 +4 %
Median lifespan (days) 944 926 +2 %
75% died before day: 1042 1050 -1 %
90% died before day: 1105 1146 -4 %
Max lifespan observed (days) 1373 1294
Number of mice at start 44 88
Animal censor events are denoted by + marks in the plot
NDGA_hi effect on survival, males, test site = UM
Log-rank test chisq = 0.027 p = 0.8694
Wang-Allison test odds ratio = 3.789 p = 0.0348
Quantiles NDGA_hi Control % difference
25% died before day: 740 794 -7 %
Median lifespan (days) 864 926 -7 %
75% died before day: 1040 1050 -1 %
90% died before day: 1210 1146 +6 %
Max lifespan observed (days) 1282 1294
Number of mice at start 48 88
Animal censor events are denoted by + marks in the plot
UT – female
UT – female      
NDGA_hi effect on survival, females, test site = UT
Log-rank test chisq = 3.7399 p = 0.0531
Wang-Allison test odds ratio = 0.3518 p = 0.2201
Quantiles NDGA_hi Control % difference
25% died before day: 706 773 -9 %
Median lifespan (days) 814 906 -10 %
75% died before day: 964 1021 -6 %
90% died before day: 1004 1100 -9 %
Max lifespan observed (days) 1213 1298
Number of mice at start 40 84
Animal censor events are denoted by + marks in the plot
UT – male
UT – male      
NDGA_lo effect on survival, males, test site = UT
Log-rank test chisq = 3.5709 p = 0.0588
Wang-Allison test odds ratio = 1.395 p = 0.5699
Quantiles NDGA_lo Control % difference
25% died before day: 581 527 +10 %
Median lifespan (days) 771 732 +5 %
75% died before day: 958 889 +8 %
90% died before day: 1145 1041 +10 %
Max lifespan observed (days) 1247 1155
Number of mice at start 47 95
Animal censor events are denoted by + marks in the plot
NDGA_mid effect on survival, males, test site = UT
Log-rank test chisq = 4.1927 p = 0.0406
Wang-Allison test odds ratio = 1.395 p = 0.5699
Quantiles NDGA_mid Control % difference
25% died before day: 661 527 +25 %
Median lifespan (days) 816 732 +11 %
75% died before day: 957 889 +8 %
90% died before day: 1102 1041 +6 %
Max lifespan observed (days) 1156 1155
Number of mice at start 47 95
Animal censor events are denoted by + marks in the plot
NDGA_hi effect on survival, males, test site = UT
Log-rank test chisq = 9.994 p = 0.0016
Wang-Allison test odds ratio = 2.362 p = 0.1368
Quantiles NDGA_hi Control % difference
25% died before day: 732 527 +39 %
Median lifespan (days) 840 732 +15 %
75% died before day: 993 889 +12 %
90% died before day: 1094 1041 +5 %
Max lifespan observed (days) 1220 1155
Number of mice at start 44 95
Animal censor events are denoted by + marks in the plot


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