Table 2.
Mean blood pressure and lipid levels at baseline and key time points during follow-up by treatment groups
| Characteristics | Visit§ | Placebo | Metformin | Lifestyle | P-value |
|---|---|---|---|---|---|
| Systolic blood pressure (mmHg) | Baseline | 123 (122–124) | 124 (123–125) | 124 (123–125) | 0.65 |
| Last DPP annual | 123 (122–124) | 123 (122–124) | 120 (120–121) | < 0.001†‡ | |
| DPPOS year 1 | 123 (122–124) | 124 (123–125) | 122 (121–122) | 0.001‡ | |
| DPPOS year 5 | 121 (120–122) | 121 (120–122) | 121 (120–122) | 0.72 | |
| Diastolic blood pressure (mmHg) | Baseline | 78 (77–79) | 78 (77–79) | 78 (78–79) | 0.58 |
| Last DPP annual | 76 (76–77) | 76 (76–77) | 74 (74–75) | < 0.001†‡ | |
| DPPOS year 1 | 75 (75–76) | 75 (75–76) | 74 (74–75) | 0.02 | |
| DPPOS year 5 | 73 (72–74) | 73 (72–74) | 73 (72–73) | 0.93 | |
| HDL cholesterol (mmol/l) | Baseline | 1.17 (1.14–1.19) | 1.19 (1.19–1.22) | 1.19 (1.19–1.22) | 0.01 |
| Last DPP annual | 1.17 (1.17–1.19) | 1.19 (1.19–1.22) | 1.22 (1.22–1.22) | < 0.001‡ | |
| DPPOS year 1 | 1.22 (1.22–1.24) | 1.24 (1.22–1.24) | 1.24 (1.22–1.24) | 0.63 | |
| DPPOS year 5 | 1.32 (1.32–1.35) | 1.32 (1.32–1.35) | 1.32 (1.32–1.35) | 0.97 | |
| Non-HDL cholesterol (mmol/l) | Baseline | 4.1 (4.0–4.1) | 4.1 (4.0–4.1) | 4.1 (4.0–4.1) | 0.89 |
| Last DPP annual | 4.0 (4.0–4.1) | 4.0 (3.9–4.0) | 3.9 (3.9–4.0) | 0.06 | |
| DPPOS year 1 | 3.9 (3.8–3.9) | 3.8 (3.7–3.8) | 3.8 (3.7–3.9) | 0.23 | |
| DPPOS year 5 | 3.5 (3.4–3.5) | 3.4 (3.4–3.5) | 3.4 (3.4–3.5) | 0.60 | |
| LDL cholesterol (mmol/l) | Baseline | 3.2 (3.2–3.3) | 3.2 (3.2–3.3) | 3.3 (3.2–3.3) | 0.69 |
| Last DPP annual | 3.2 (3.2–3.3) | 3.2 (3.1–3.2) | 3.2 (3.2–3.3) | 0.18 | |
| DPPOS year 1 | 3.1 (3–3.1) | 3 (3–3.1) | 3.1 (3–3.1) | 0.34 | |
| DPPOS year 5 | 2.7 (2.7–2.8) | 2.7 (2.6–2.7) | 2.7 (2.7–2.8) | 0.41 | |
| LDL size (floatation rate × 10†‡) | Baseline | 263 (261–265) | 266 (264–268) | 265 (263–267) | 0.06 |
| Last DPP annual | 265 (264–267) | 267 (265–268) | 270 (269–272) | < 0.001†‡ | |
| DPPOS year 1 | 262 (261–264) | 264 (263–266) | 264 (262–265) | 0.31 | |
| DPPOS year 5 | 265 (264–267) | 265 (264–267) | 267 (265–268) | 0.31 | |
| Triglycerides(mmol/l) | Baseline | 1.66 (1.6–1.72) | 1.57 (1.51–1.62) | 1.57 (1.53–1.63) | 0.026 |
| Last DPP annual | 1.51 (1.48–1.56) | 1.53 (1.49–1.56) | 1.37 (1.33–1.4) | < 0.001†‡ | |
| DPPOS year 1 | 1.45 (1.41–1.49) | 1.44 (1.4–1.48) | 1.4 (1.37–1.44) | 0.13 | |
| DPPOS year 5 | 1.4 (1.37–1.44) | 1.41 (1.38–1.45) | 1.38 (1.34–1.41) | 0.46 | |
| Anti-hypertensive medications (%) | Baseline | 15.5 | 16.1 | 17.5 | 0.48 |
| Last DPP annual | 27.7 | 28.8 | 25.7 | 0.26 | |
| DPPOS year 1 | 36.9 | 39.1 | 35.3 | 0.43 | |
| DPPOS year 5 | 50.9 | 52 | 46.7 | 0.09 | |
| Lipid lowering medications (%) | Baseline | 5.4 | 5.6 | 4.4 | 0.53 |
| Last DPP annual | 15.5 | 15 | 11.8 | 0.04 | |
| DPPOS year 1 | 21.1 | 20.8 | 17.8 | 0.12 | |
| DPPOS year 5 | 37.4 | 39.2 | 32.5 | 0.01‡ |
Data are presented as mean (95%) and percentage as appropriate.
P-value from treatment group comparison using ANOVA is not adjusted for multiple comparisons. P-value from treatment group comparison using ANOVA is not adjusted for multiple comparisons, with pairwise significance indicated by:
(P < 0.01 for placebo vs. metformin);
(P < 0.01 for placebo vs. lifestyle);
(P < 0.01 for metformin vs. placebo).
The visits represent baseline when randomization occurred; last DPP annual with average follow-up of 2.9 years (end of masked phase of the study); DPPOS year 1 with average follow-up of 5 years (start of follow-up study after bridge when all groups were offered group-implemented lifestyle curriculum); and DPPOS year 5 with average follow-up of 9 years (end of first phase of DPPOS after 4 years of group-implemented quarterly lifestyle sessions).
DPP, Diabetes Prevention Program; DPPOS, Diabetes Prevention Program Outcomes Study.