Table 2

Baseline variables of the included trials

‡Data are participants with hypertension at baseline.

TrialSystolic and diastolic blood pressure (mm Hg)* Cholesterol concentration (mmol/L)*Triglyceride concentration (mmol/L)*No of patients given aspirin, antihypertensive, or lipid lowering treatmentPrevious cardiovascular disease*
Total Low density lipoproteinHigh density lipoprotein
Altuntas et al, 200343NR5.8 (8.0)/5.3 (5.4)3.3 (0.9)/3.1 (4.3)1.3 (0.9)/1.1 (0.9)3.6 (13.0)/2.2 (4.7)NRNR
Avilés-Santa et al, 199948NR5.5 (1.0)/5.6 (1.5)3.1 (0.8)/3.5 (1.1)0.9 (0.3)/0.9 (0.3)2.3 (1.3)/2.5 (2.1)NRNR
Civera et al, 200736146 (26)/78 (10); 152 (23)/81 (11)NRNRNRNRNRNR
Douek et al, 20054146 (20)/84 (11); 145 (19)/84 (11)5.1 (0.96)/5.1 (0.98)NR1.1 (0.22)/1.1 (0.33)2.9 (2.0)/2.5 (1.4)NRNR
Galani et al, 201137136.9/80.7; 136.4/79.8NRNRNRNRNRNR
Giugliano et al, 199249155 (20)/87.5 (10); 155(20)/85 (10)5.9 (0.6)/6.03 (0.6)NR1.05 (0.3)/1.0 (0.3)2.9 (0.9)/2.6 (0.5)NR/5/NR
NR/4/NR		NR
Heine et al, 199529,32,33NRNRNRNRNRNRNR
Hermann et al, 200150155 (17)/84 (8); 153 (17)/88 (9)6.1 (1.2)/6.0 (1.3)3.9 (0.8)/3.7 (1.3)1.2 (0.3)/1.1 (0.3)2.8 (1.7)/2.5 (1.3)NR19% of included participants
Hirsch et al, 199934NRNRNRNRNRNRNR
HOME, 20096,17160 (25)/86 (12); 159 (25)/86 (11)5.5 (1.3)/5.4 (1.2)3.6 (1.1)/3.4 (1.0)1.3 (0.4)/1.3 (0.4)1.7 (1.2)/1.9 (1.5)NR/93/32
NR/75/31		59/53†
Kabadi et al, 200638NRNRNRNRNRNRNR
Kokic et al, 200342NRNRNRNRNRNRNR
Kokic et al, 201045NRNRNRNRNRNRNR
Kvapil et al, 200539NRNRNR1.2 (0.3)/1.2 (0.3)2.8 (2.4)/2.6 (2.5)NRNR
Onuchin et al, 201040161 (22.1)/93.2 (8.5); 161 (23.2)/94.9 (8.3)6.3 (1.4)/6.5 (1.6)NRNR3.4 (1.4)/3.0 (1.5)NRNR
Ponssen et al, 200035NRNRNRNRNRNRNR
Relimpio et al, 199818153.5 (24)/81.6 (10.8); 148.(24.8)/80 (14.4)5.84 (1.0)/5.92 (1.2)3.84 (0.51)/3.71 (1.15)1.36 (0.18)/1.34 (0.35)2.01 (1.1)/2.42(1.53)NR/10/1
NR/7/5		13/13‡
Robinson et al, 1998, study 130138 (16)/78 (9)§6.0 (1.1)3.9 (1.2)1.1 (0.3)2.2 (1.3)NRNR
Robinson et al, 1998, study 230144 (23)/87 (11)§6.4 (1.2)4.1 (1.5)1.2 (0.4)2.5 (2.4)NRNR
Schnack et al, 199631NRNRNRNRNRNRNR
SDDSa, 201144,65NRNRNRNRNRNRNR
SDDSb, 201144,65NRNRNRNRNRNRNR
Strowig et al, 200247NR4.9 (1.1)/4.9 (1.1)2.8 (1.1)/2.8 (0.7)0.8 (0.2)/1.0 (0.3)2.5 (1.8)/2.0 (1.7)NRNR
Ushakova et al, 200741NRNRNRNRNRNRNR
Vähätalo et al, 200746NRNRNRNRNRNRNR
Yilmaz et al, 200751NR4.6 (0.7)/5.4 (1.8)2.5 (0.6)/3.2 (0.5)1.3 (0.4)/1.3 (0.2)1.7 (0.9)/2.5 (2.4)NRNR
Yki-Järvinen et al, 19993,66NR5.9 (1.4)/5.8 (1.5)NR1.2 (0.5)/1.2 (0.5)2.4 (1.9)/0.9 (2.4)NR/2/NRNR

NR=not reported; SDDS=South Danish Diabetes Study; SDDSa=intervention group in the South Danish Diabetes Study prescribed neutral protamine Hagedorn insulin in combination with metformin or placebo; SDDSb=intervention group in the South Danish Diabetes Study prescribed insulin aspart in combination with metformin or placebo; Robinson study 1=participants were exclusively treated with insulin at entry to trial and randomised to metformin or placebo in addition to insulin; Robinson study 2=participants received combination of metformin and insulin at entry to the trial, but after entry to the trial participants were randomised to receive either metformin or placebo.

*Data are intervention group (insulin and metformin)/control group (insulin (and placebo)); data for continuous variables are mean (standard deviation) if reported, unless stated otherwise.

†Data only for participants who completed the trial.

§Data only reported for the total number of participants undergoing randomisation.