Author | Country | Study design | Sample size | Age | Male n (%) | Outcomes |
---|---|---|---|---|---|---|
Akesson, 2010 [15] | Sweden | Cross- sectional | 46 T2D 20 Controls | T2D (55.8 ± 43.4) Control (NR) | 38 (83) | Patients with T2D had decreased peripheral natural killer (NK) cells compared to controls. |
Berrou, 2013 [16] | France | Cross- sectional | 51 T2D 54 Controls | T2D (51.3 ± 14.4) Control (NR) | 33 (65) | The levels of NK cells were similar between patients with T2D and healthy controls. |
Guo, 2012 [27] | China | Cross- sectional | 16 T2D 9 Controls | T2D (40 ± 35.7) Control (45 ± 20.4) | 9 (56) | There was no significant difference in the levels of NK cells between T2D patients and control. |
Kim, 2019 [28] | S. Korea | Cross- sectional | 21 T2D, 13 Controls | T2D (60.71 ± 6.99) Control (55 ± 13.76) | 8 (38) | Patients with diabetes had lower NK cell activity compared with participants with controls. Comparable levels of lipid profiles was reported between T2D and controls. |
Lynch, 2009 [35] | Ireland | Cross- sectional | 26 T2D 26 Controls | T2D (45.5 ± 5.8) Control (42.6 ± 9.8) | 7 (27) | The levels of circulating NK cells were decreased in T2D compared to controls. NK cells from T2D, expressed elevated levels of the inhibitory markers NKB1 and CD158b as well as CD69, an activation marker. Comparable levels of high-density lipoprotein (HDL) and low-density lipoprotein (LDL) were observed between T2D patient and control. However, triglycerides levels were higher in T2D group in comparison to controls. |
Medellin-Garibay, 2015 [23] | Mexico | Prospective cohort | 18 T2D 24 Control | T2D (45.4 ± 11.4) Control (35.8 ± 6.6) | 9 (50) | The levels of NK cells in circulation were similar between T2D and the control. Patients with T2D had increased levels of triglycerides, total cholesterol and LDL coupled with decreased Levels of HDL when compared to controls. |
Simar, 2014 [21] | Denmark | Cross- sectional | 6 T2D, 4 Controls | T2D (44.1 ± 6.5) Control (34.8 ± 3) | NR | There were no significant differences observed in the levels of NK cells between T2D groups and controls. |
Nam, 2018 [25] | R. Korea | Cross- sectional | 33 T2D 35 Controls | T2D (61.4 ± 5.9) Control (57.8 ± 5.3) | 21 (64) | The level of NK cells and their functional activity were not different between T2D and control groups. |
Nekoua, 2016 [24] | Benin | Cross- sectional | 45 T2D 43 Controls | NR | 21 (47) | The levels of NK cells were comparable between the T2D patients and the controls. Patients with T2D had lower levels of total cholesterol and triglycerides. However, there was no significant difference in LDL levels. |
Olson, 2015 [20] | USA | Cross- sectional | 154 T2D 775 Controls | T2D (66.9 ± 9.5) Control (65.4 ± 10) | 84 (55) | No significant differences between the levels of NK cells in patients with T2D versus controls. |
Piatkiewicz, 2013 [14] | Poland | Cross- sectional | 18 T2D 18 Controls | T2D (53.6 ± 7.0) Control (52.4 ± 7.0) | 9 (50) | Patients with T2D had significantly increased levels of NK cells in comparison to the healthy controls. However, the cytotoxic activity of NK cells in T2D individuals was reduced compared to controls. |
Singh, 2019 [22] | Sweden | Cross- sectional | 16 T2D, 13 Controls | T2D (64.0 ± 2.0) Control (61.6 ± 2.9) | NR (70) | Patients with T2D and healthy controls had comparable levels of NK cells |
Xiaohong, 2018 [19] | China | Cross- sectional | 41 T2D 30 Controls | NR | NR | Patients with T2D had significantly increased levels of peripheral NK cells compared to controls. |