TABLE 3.

Relationships between biofluid lithium levels and blood chemistry

Serum analyte (n)	Unadjusted (r, p)			Adjusted for covariates a (r, p)
	Saliva lithium	Serum lithium	Ratio	Saliva lithium	Serum lithium	Ratio
Na+ (85)	0.04, 0.71	−0.07, 0.51	0.05, 0.65	0.03, 0.80	−0.06, 0.60	0.01, 0.91
K+ (82)	0.26, 0.02	0.30, 0.007	−0.08, 0.47	0.25, 0.03	0.32, 0.004	−0.16, 0.17
Cre (85)	0.03, 0.76	0.00, 0.98	0.07, 0.57	0.10, 0.37	0.16, 0.16	−0.09, 0.44
TSH (80)	0.14, 0.23	0.09, 0.45	0.07, 0.57	0.17, 0.15	0.07, 0.56	0.11, 0.35
WBC (32)	0.13, 0.48	0.12, 0.53	0.09, 0.63	0.06, 0.78	−0.05, 0.82	0.21, 0.31

Abbreviations: Na+, sodium; K+, potassium; Cre, creatinine; TSH, thyroid‐stimulating hormone; WBC, white blood cell count.

Values in bold are statistically significant (p < 0.05).

^a Covariates: daily lithium dose, dosing schedule, recruitment site, diabetes, smoking.