Table 2.
Differences in MedDiet adherence and in cognitive composites at each time point and in the mean change from baseline between individuals with type 2 diabetes from subgroup 1 (T2D-S1) treated with metformin and not treated with metformin (matched with inverse probability of treatment weights).
| Variable | Time | T2D-S1 No-Metformin | T2D-S1 Metformin | Differences | Differences in the mean change | ||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
| [N = 36]a | [N = 87]b | at each time point | (95%CI) from baseline | ||||||||
| Missing | Mean | Missing | Mean | Cohen's D | Effect | P d | No-Metformin | Metformin | P e | ||
| [N (%)] | (95% CI) | [N (%)] | (95% CI) | (95% CI)* | Sizec | ||||||
| er-MedDiet adherence score | Baseline | 0 (0) | 7.7 (6.8, 8.5) | 0 (0) | 7.7 (7.2, 8.3) | 0.03 (−0.36, 0.41) | VS | 0.752 | |||
| 1 year | 1 (2.8) | 12.1 (10.9, 13.3) | 3 (3.4) | 11.6 (11, 12.2) | −0.16 (−0.56, 0.23) | S | 0.427 | 4.4 (3.4, 5.5) | 3.9 (3.2, 4.6) | 0.476 | |
| 3 years | 1 (2.8) | 12.6 (11.8, 13.4) | 8 (9.2) | 11.5 (10.9, 12.1) | −0.44 (−0.84, −0.02) | S | 0.031 | 4.9 (3.9, 5.9) | 3.9 (3.3, 4.4) | 0.145 | |
| Memory composite (z-score) | Baseline | 1 (2.8) | −0.17 (−0.46, 0.12) | 3 (3.4) | 0.1 (−0.03, 0.23) | 0.38 (−0.02, 0.79) | S | 0.115 | |||
| 1 year | 7 (19.4) | 0.1 (−0.21, 0.41) | 13 (14.9) | 0.18 (0.03, 0.33) | 0.11 (−0.32, 0.54) | VS | 0.795 | 0.2 (−0.03, 0.42) | 0.01 (−0.11, 0.14) | 0.307 | |
| 3 years | 6 (16.7) | 0.33 (0.04, 0.63) | 16 (18.4) | 0.29 (0.14, 0.44) | −0.06 (−0.49, 0.36) | VS | 0.557 | 0.38 (0.15, 0.62) | 0.1 (−0.05, 0.25) | 0.036 | |
| Executive functions composite (z-score)a, b | Baseline | 10 (34.5) | −0.14 (−0.42, 0.14) | 21 (34.4) | 0.13 (−0.02, 0.28) | 0.51 (−0.06, 1.08) | M | 0.086 | |||
| 1 year | 10 (34.5) | −0.13 (−0.47, 0.21) | 14 (23) | 0.09 (−0.04, 0.21) | 0.39 (−0.16, 0.93) | S | 0.333 | 0.08 (0.00, 0.16) | −0.02 (−0.17, 0.13) | 0.293 | |
| 3 years | 14 (48.3) | 0.23 (−0.14, 0.6) | 28 (45.9) | 0.14 (−0.01, 0.28) | −0.18 (−0.79, 0.44) | S | 0.557 | 0.36 (0.13, 0.59) | 0.02 (−0.09, 0.14) | 0.005 | |
| Global cognition composite (z-score)a, b | Baseline | 10 (34.5) | −0.1 (−0.35, 0.14) | 22 (36.1) | 0.13 (−0.02, 0.27) | 0.48 (−0.1, 1.04) | M | 0.124 | |||
| 1 year | 10 (34.5) | 0.02 (−0.34, 0.37) | 15 (24.6) | 0.15 (0.02, 0.29) | 0.23 (−0.31, 0.77) | S | 0.676 | 0.12 (−0.05, 0.29) | 0.12 (0, 0.23) | 0.511 | |
| 3 years | 14 (48.3) | 0.34 (−0.01, 0.69) | 28 (45.9) | 0.19 (0.03, 0.34) | −0.28 (−0.9, 0.34) | S | 0.304 | 0.29 (0.10, 0.49) | −0.02 (−0.11, 0.07) | 0.001 | |
N = 29 and
N = 61 when excluding participants from University of Valencia study site that did not receive all the tests from executive functions and global cognition.
Effect Size: VS = very small (Cohen's d <0.2); S = small [Cohen's d (0.2–0.5)]; M = medium [Cohen's d (0.5–0.8)]; L = large [Cohen's d (0.8–1.2)]; VL = very large (Cohen's d ≥ 1.2).
ANOVA from multivariable-adjusted linear model.
ANOVA from multivariable-adjusted linear mixed effects model.
Inverse probability of treatment weighting (IPTW) was applied to all analyses to weight each individual with his/her inverse probability of being treated with metformin, generating a pseudo-population with (almost) perfect covariate balance. All models were adjusted by diagnosis of sleep apnoea.
Reference group= No-Metformin. Bold values denote statistical significance at the p <0.05 level.