The association of glycogen synthase kinase-3beta (GSK-3β) gene polymorphism with kidney function in long-term lithium-treated bipolar patients

International Journal of Bipolar Disorders

Table 3 Analysis of genotype differences in relation to kidney function

	T/T	T/C	C/C	T/T vs. T/C vs. C/C	T/T vs. T/C + C/C	T/T + T/C vs. C/C
	N= 34	N= 37	N= 7	(ANOVA)	t test	t test
Urine specific gravity	1,012 ± 0.007	1,013 ± 0.007	1,019 ± 0.008	p = 0.052	p = 0.215	p = 0.035
Serum creatinine, total (mg/dl)	0.89 ± 0.20	0.99 ± 0.28	0.98 ± 0.23	p = 0.448	p = 0.074	p = 0.603
Male	1.19 ± 0.25	1.16 ± 0.32	1.22 ± 0.10	p = 0.939	p = 0.884	p = 0.781
Male	N = 6	N = 16	N = 3	p = 0.939	p = 0.884	p = 0.781
Female	0.83 ± 0.12	0.85 ± 0.14	0.80 ± 0.06	p = 0.774	p = 0.772	p = 0.515
Female	N = 28	N = 21	N = 4	p = 0.774	p = 0.772	p = 0.515
Estimated glomerular filtration rate (ml/min/1.73 m²)	71 ± 13	71 ± 16	68 ± 9	p = 0.977	p = 1.000	p = 0.606
Serum neutrophil gelatinase-associated lipocalin (ng/ml)	288 ± 89	321 ± 142	248 ± 81	p = 0.441	p = 0436	p = 0.216
Urine beta2-microglobulin (μg/ml)	0.22 ± 0.24	0.16 ± 0.14	0.13 ± 0.05	p = 0.279	p = 0.162	p = 0.410

The p values of the differences in kidney function values are expressed as means ± SD. Italicized p value indicates urine specific gravity significantly higher in C/C patients compared to remaining genotypes combined.