Table 2.
Overall HDL effect by niacin ER dose.
| Demographics and lipids | 500 mg niacin ER dose | 1000 mg niacin ER dose | P valueb | ||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
| n | Baseline HDL-C levels Mean (SD) |
Follow-up HDL-C levels Mean (SD) |
HDL-C effect Mean (SD) |
P valuea | n | Baseline HDL-C levels Mean (SD) |
Follow-up HDL-C levels Mean (SD) |
HDL-C effect Mean (SD) |
P valuea | ||
| Gender | |||||||||||
| Males | 480 | 37.1 (0.4) | 39.4 (0.4) | 0.08 (0.01) | <0.001 | 120 | 39.0 (0.9) | 41.6 (0.9) | 0.08 (0.02) | 0.029 | 0.768b |
| Females | 200 | 45.5 (1.1) | 49.3 (1.2) | 0.10 (0.01) | 0.019 | 34 | 48.5 (2.6) | 57.4 (3.6) | 0.19 (0.03) | 0.048 | 0.021b |
| P valuec | <0.001 | <0.001 | 0.221 | 0.001 | <0.001 | 0.009 | 0.053d | ||||
| Age (years) | |||||||||||
| 18 to 40 | 79 | 37.9 (1.2) | 40.0 (1.1) | 0.10 (0.04) | 0.196 | 12 | 38.9 (2.9) | 40.4 (1.7) | 0.07 (0.05) | 0.659 | 0.660b |
| 41 to 65 | 516 | 39.4 (0.5) | 42.2 (0.6) | 0.08 (0.01) | <0.001 | 131 | 41.3 (1.1) | 45.8 (1.3) | 0.12 (0.02) | 0.008 | 0.057b |
| ≥66 | 85 | 42.5 (1.4) | 45.5 (1.4) | 0.08 (0.02) | 0.126 | 11 | 41.2 (2.2) | 41.9 (1.8) | 0.03 (0.05) | 0.803 | 0.335b |
| P valued | 0.032 | 0.018 | 0.842 | 0.799 | 0.343 | 0.242 | 0.613d | ||||
| HDL-C mg/dL (both genders) | |||||||||||
| 40 | 423 | 32.8 (0.3) | 36.3 (0.4) | 0.12 (0.01) | <0.001 | 87 | 33.5 (0.5) | 37.7 (0.8) | 0.13 (0.02) | <0.001 | 0.437b |
| ≥40 | 257 | 50.8 (0.7) | 52.3 (0.8) | 0.03 (0.01) | 0.168 | 67 | 50.9 (1.2) | 54.7 (1.9) | 0.07 (0.02) | 0.096 | 0.094b |
| P valuec | <0.001 | <0.001 | <0.001 | <0.001 | <0.001 | 0.037 | 0d | ||||
| LDL-C mg/dL | |||||||||||
| <130 | 264 | 39.0 (0.7) | 41.3 (0.8) | 0.07 (0.01) | 0.025 | 88 | 40.6 (1.1) | 44.9 (1.2) | 0.12 (0.02) | 0.008 | 0.160b |
| ≥130 | 176 | 41.8 (0.9) | 44.6 (1.0) | 0.08 (0.02) | 0.031 | 33 | 44.7 (2.7) | 48.9 (3.5) | 0.09 (0.03) | 0.344 | 0.802b |
| P valuec | 0.011 | 0.006 | 0.474 | 0.161 | 0.291 | 0.489 | 0.472d | ||||
| TG mg/dL | |||||||||||
| <150 | 192 | 44.0 (1.1) | 46.5 (1.1) | 0.08 (0.02) | 0.102 | 60 | 46.6 (1.6) | 50.4 (2.2) | 0.08 (0.02) | 0.166 | 0.899b |
| ≥150 | 483 | 38.0 (0.4) | 40.9 (0.5) | 0.08 (0.01) | <0.001 | 93 | 37.6 (1.0) | 41.8 (1.1) | 0.12 (0.02) | 0.005 | 0.060b |
| P valuec | <0.001 | <0.001 | 0.943 | <0.001 | 0.001 | 0.111 | 0.362d | ||||
| TC mg/dL | |||||||||||
| <200 | 301 | 36.8 (0.6) | 39.5 (0.6) | 0.09 (0.01) | 0.001 | 96 | 39.6 (1.0) | 43.7 (1.2) | 0.11 (0.02) | 0.007 | 0.362b |
| ≥200 | 375 | 42.2 (0.6) | 44.9 (0.7) | 0.08 (0.01) | 0.004 | 57 | 43.7 (1.9) | 47.6 (2.4) | 0.10 (0.03) | 0.200 | 0.530b |
| P valuec | <0.001 | <0.001 | 0.259 | 0.052 | 0.144 | 0.549 | 0.195d | ||||
Definition of lipids: HDL-C: high-density lipoprotein cholesterol; LDL-C: low-density lipoprotein cholesterol; TG: triglycerides; TC: total cholesterol.
a P value tested the null hypothesis that there is no difference in the baseline and follow-up HDL-C levels using the Student's t-test.
b P value tested the null hypotheses that there is no difference in the mean HDL-C effect across niacin ER dose groups using the Student's t-test.
c P value tested the null hypothesis that there is no difference in the mean HDL-C effect across each risk factor/lipid level category using the Student's t-test.
d P value tested the null hypothesis that there is no difference in the mean HDL-C effect across each risk factor/lipid level category using the F-statistic.