Role of Salivary Biomarkers in Cystic Fibrosis: A Systematic Review

Table 1

Characteristics and outcomes of the included studies.

Author, year	Type of study	Quality	Characteristics of participants		Saliva parameters	Outcomes in the CF group compared to the control group
			CF group	Control group
Aps et al., 2002 [14]	Case control	B	CF homozygotes; CF heterozygotes		Chloride	Increased^β
					Potassium	Increased^α
					Sodium	Increased^α
					Phosphate	Increased^α
					Osmolarity	Increased^α
					Bicarbonate	Increased^β
					Calcium	Decreased^β
Minarowska et al., 2007 [16]	Case control		(12 F, 14 M)	(15 F, 13 M)	Cathepsin D	Increased^α
					Proteins	Increased^α
					Glycoprotein	Increased^β
Minarowski et al., 2008 [21]	Case control	C	Not reported	(i) Healthy nonsmokers; (ii) Healthy smokers	Thiocyanate (SCN-)	Decreased^α
Livnat et al., 2010 [15]	Case control	B	(9 F, 13 M)	Non-CF bronchiectasis; (6 F, 8 M); Healthy; (6 F, 8 M)	Salivary flow rates	Reported that it is NS compared with CF patients
					pH	Exactly the same^β
					Iron, albumin, potassium	Increased^β
					Calcium	Decreased^β
					Magnesium	Decreased^β
					Lactate dehydrogenase	Decreased^α
					Total protein	Increased^β
					α-Amylase	Increased^β
					Oral peroxidase	Decreased^β
					Superoxide dismutase	Increased^β
					Uric acid	Increased^β
					Total antioxidant status	Increased^β
Gonçalves et al., 2013 [18]	Case control	B			Salivary volume and pH	Decreased^α
					Na, Cl, K	Increased^α
					Calcium	Decreased^β
					Glucose, lactate, bicarbonate	Increased^β
da Silva Modesto et al., 2015 [17]	Case control	B	(47.6% F, 52.4% M)	(64.3% F, 35.7% M)	Salivary flow rate	Decreased^α
					pH	Increased^β
					Buffering capacity	Decreased^α only in pH range 6.9–6.0
					Total protein	Increased^α
					α-Amylase activity	Decreased^α
					Peroxidase activity	Decreased^α
					Sialic acid concentration	Decreased^α
Nie et al., 2015 [5]	Cross-sectional	A	Microarray; (39 F, 32 M); SDReader; (58 F, 59 M)	Microarray; (34 F, 22 M); SDReader; (30 F, 20 M)		Microarray	SDReader
					VEGF	Increased^α	Increased^β
					IP-10	Increased^α	Increased^α
					IL-8	Increased^α	Increased^α
					EGF	Increased^α	Increased^β
					MMP-9	Decreased^α	Decreased^α
					IL-1β	Decreased^β	Decreased^α
Gonçalves et al., 2019 [20]	Case control	B	(30 F, 27 M)	(54 F, 49 M)	Salivary sodium, salivary chloride	Increased^α
Malkovskiy et al., 2019 [19]	Case control	B	(13 F, 12 M) (14 with stimulated and 11 with unstimulated saliva); CF patients with CFTR modulators; (4 F, 7 M) (2 with stimulated and 9 with unstimulated saliva)	(9 F, 6 M, 8 unknown) (11 with stimulated and 12 with unstimulated saliva)	SCN− using colorimetry	Decreased^β
					SCN− using Raman spectroscopy	Decreased^α

^αSignificant difference; ^βnonsignificant difference.