Table 1.
Descriptive characteristics of included articles
| References | Participants | n | Age | Duration, design | Intervention | Control | Available Outcomes | Limitation |
| Szwejkowski et al [22], 2013 |
Patients with hyperuricemia and T2DM |
66 (59 completers) |
64.63±8.79 years |
9 months, RCT |
Allopurinol 600 mg twice per day (n=33) |
Placebo (n=33) | Difference 600 mg allopurinol versus control (95% CI): UA (µmo/l): -251.00 [-313.02, -188.98] FPG (mmol/l): -0.43 [-2.39, 1.53] FINS (µU/ml): 4.77 [-4.27, 13.81] |
Not adjusted for diabetes duration, kinds or dosage of hypoglycemic agents. Not aims to evaluate the effect of uric acid-lowering therapy on β-cell function or insulin sensitivity. |
| Perez-Pozo et al [23], 2010 |
Participants were administered fructose 200 g daily |
83 (74 completers) |
40.65 years (mean 51± 1.3 years) |
2 weeks, RCT | Allopurinol 200 mg/d (n=38) |
No treatment (n=36) |
Difference 100mg allopurinol versus control (95% CI) UA (µmo/l): -178.00 [-182.29, -173.71] FPG (mmol/l) : 0.10 [0.07, 0.13] (µU/ml): -0.58 [-0.85,-0.31] HOMA-IR : -0.39 [-0.85, 0.07] |
Participates were induced to hypeluricemia by fructose. Not adjusted for diabetes duration, kinds or dosage of hypoglycemic agents. Not to evaluate the effect of uric acid-lowering therapy on β-cell function or insulin sensitivity. |
| Takir et al [24], 2014 |
Patients with hyperuricemia |
73 | 50.76 ± 13.78 years |
3 months, RCT | Allopurinol 300 mg/d (n=40) |
No treatment (n=33) |
Difference 300 mg allopurinol versus control (95% CI): UA (µmo/l): -72.00 [-95.86, -48.14] FPG (mmol/l) :-0.40 [-0.61,-0.19] FINS (µU/ml): -2.00 [-3.99,-0.01] HOMA-IR : -3.40 [-5.22, -1.58] |
Choice of allopurinol versus control was performed by the treating physician. Hence, it was not a pure randomization. |
| Liu et al [25], 2015 |
Patients with T2DM and hyperuricemia |
176 (152 completers) |
50.5 ± 10.49 years |
3 years, RCT | Allopurinol (starting from 100 mg/day) adjust to SUA (n=88) |
No treatment when the SUA was less than 476 µmol/L (n=88) |
Difference allopurinol versus control (95% CI) UA (µmo/l): -138.00 [-142.13, -133.87] FPG (mmol/l) : 0.01 [-0.11, 0.13] FINS (µU/ml): -0.51 [-0.73, -0.29] HOMA-IR : -0.67 [-0.99, -0.34] |
Open-label design and the lack of a placebo control. Not adjusted for diabetes duration, kinds or dosage of hypoglycemic agents. Not aims to evaluate the effect of uric acid-lowering therapy on β-cell function or insulin sensitivity. |
| Ding et al [26], 2012 |
Patients with hyperuricemia |
60 | 48.0±11.7 years | 3 ∼ 8 months (mean 4.3 months), RCT |
Allopurinol 100 mg twice a day (n=30) |
No treatment (n=30) |
Difference 200mg allopurinol versus control (95% CI): UA (µmo/l): -140.6 [-2.63,-1.69] FPG (mmol/l) : 0.17 [-0.17,0.51] FINS (µU/ml): 7.28 [5.62, 8.94] HOMA-IR: 0.16 [-0.34, 0.67] |
Unclear for random sequence generation or double-blind design. Not adjusted for kinds or dosage of hypoglycemic agents. |
| Le et al [27], 2013 |
Patients with hyperuricemia and IGT |
40 | 44.65±2.27 years |
6 months, RCT | allopurinol 100 mg three times a day (n=20) |
Low purine and diabetes diet (n=20) |
Difference 300mg allopurinol versus control (95% CI) UA (µmo/l): -203.00 [-221.97, -184.03] FPG (mmol/l) : -0.66 [-0.86, -0.46] FINS (µU/ml): -10.56 [-13.39, -7.73] HOMA-IR : -3.56 4.59, -2.53] |
Unclear for random sequence generation or double-blind design. Not adjusted for kinds or dosage of hypoglycemic agents. |
| Ogino al [28], 2016 |
Patients with hyperuricemia |
14 | 60±5 years | 8 weeks, randomized crossover study |
Benzbromarone 50 mg/d (n=7) |
Placebo (n=7) | Difference 50 mg benzbromarone versus control (95% CI): UA (µmo/l): -128.90 [-156.88, -100.92] FPG (mmol/l): -0.33 [-0.56, -0.10] FINS (µU/ml): -7.80 [-9.26, -6.34] HOMA-IR : -1.22 [-1.72, -0.72] |
Participates are patients with CHF and under the treatment of ACEIs, which may affect insulin sensitivity. Excluded diabetes mellitus and antidiabetic therapy. Short duration and small sample size. Not aims to evaluate the effect of uric acid-lowering therapy on β-cell function or insulin sensitivity. |
Abbreviations: T2DM, Type 2 diabetes mellitus; RCT, randomized controlled trial; UA, uric acid; FPG. fasting plasma glucose; FINS, fasting insulin; HOMA-IR, homeostasis model assessment of insulin resistance; IGT, impaired glucose tolerance; CHF, chronic heart failure; ACEIs, angiotensin converting enzyme inhibitors.