Table 2.
Characteristics of study populations and trial designs of four influential trials of angiotensin converting enzyme inhibitors and angiotensin II receptor antagonists in patients with diabetic nephropathy. Values are means (standard deviations) unless stated otherwise
| Variable | Micro-HOPE 20004 | Lewis et al 19935 | Brenner et al 20017 | Lewis et al 20018 |
|---|---|---|---|---|
| Treatments | Ramipril v placebo | Captopril v placebo | Losartan v placebo | Irbesartan v placebo |
| Characteristics of patients at baseline*: | ||||
| Age (years) | 65.6 (6.6) | 35.0 (7.0) | 60.0 (7.0) | 58.3 (8.2) |
| No (%) with type 2 diabetes | 3 | 0 | 100 | 100 |
| Hypertension | Yes | Yes | Yes | Yes |
| Systolic blood pressure (mm Hg) | 142.3 (19.5) | 140.0 (20.0) | 153.0 (20.0) | 158.0 (20.0) |
| Diastolic blood pressure (mm Hg) | 79.3 (10.7) | 86.0 (12.0) | 82.0 (11.0) | 87.0 (11.0) |
| Arterial pressure (mm Hg) | NA | 104.0 (13.0) | 106.0 (11.6) | NA |
| Serum creatinine concentration (μmol/l) | 94.0 (27.6) | 114.4 (35.2) | 167.2 (44.0) | 148.7 (50.12) |
| Glomerular filtration rate (ml/min) | NA | 79.0 (35.0) | NA | NA |
| Urinary protein excretion (g/24 h) | NA | 3.0 (2.6) | NA | 2.9 (1.8-5.2)† |
| Stage of nephropathy | Microalbuminuria | Macroalbuminuria | Macroalbuminuria | Macroalbuminuria |
| Percentage of patients with cardiac disease (definition) | 80% (history of coronary artery disease, stroke, or peripheral vascular disease) | Excluded if scored >111 on criteria for New York Heart Association >III; no other data available | 10% (angina, myocardial infarction, stroke, or coronary revascularisation) | 27% (none) |
| Trial design and event rates (placebo group): | ||||
| Run-in phase‡ | Yes | No | No | No |
| Equalisation of blood pressure | No | Yes | No | Yes |
| Target blood pressure (systolic/diastolic, mm Hg) | NA | 140/90 | NA | <135/85 |
| Active v placebo group blood pressure (systolic/diastolic) at end of treatment (mm Hg) | 139.8/76.7 v 142.9/77.0 | 134.0/82.0 v 136.0/84.0 | 140.0/74.0 v 142.0/74.0 | 140.0/77.0 v 141.0/77.0 |
| Duration of study (months) | 54 | 48 | 48 | 52 |
| Mortality (%) | 20.7 | 6.9 | 20.3 | 16.3 |
| End stage renal disease (%) | 4.3 | 15.3 | 25.5 | 15.3 |
| Doubling of serum creatinine concentration (%) | 9.3 | 21.3 | 25.6 | 21.3 |
| Progression from microalbuminuria to macroalbuminuria (%) | 21.6 | NA | NA | NA |
| Regression from microalbuminuria to normoalbuminuria (%) | 13.1 | NA | NA | NA |
| Trial quality: | ||||
| Allocation concealment | Adequate | Unclear | Unclear | Adequate |
| Blinding of participants | Yes | Yes | Yes | Yes |
| Blinding of investigators | Yes | Yes | Yes | Yes |
| Blinding of outcome assessors | Yes | No | No | Yes |
| Intention to treat analysis | Yes | Yes | Yes | Yes |
| Lost to follow up (%) | 1.0 | 1.0 | 0.2 | 1.0 |
NA=not applicable.
*
Mean values provided for placebo group.
†
Data given as median (interquartile range).
‡
To test compliance and toxicity.