Table 4.
Characteristics of included studies considering only quantitative assessments of saliva.
| Author, Year | Setting | Study Group (F/M); Age | Control Group (F/M); Age | AITD Diagnosis | Inclusion Criteria | Exclusion Criteria | Smoking Status | Pharmacological Treatment | Method of Salivation Assessment |
|---|---|---|---|---|---|---|---|---|---|
| Agha-Hosseini et al., 2016 [32] | Iran | 40 (40/0); 39.20 ± 13.8 |
40 (40/0); 38.95 ± 14.2 |
HT | Diagnosed with HT; euthyroidism at the time of the study | Smoking; neurologic drugs; steroids therapy; pregnancy; breast feeding; taking xerogenic medical agents; oral candidiasis; unfavorable oral health conditions (PPD > 3 mm); history of head and neck radiation; diagnosis of an immunological disorder, diabetes, any infectious disease, any malignancy, or any other systemic disease | Non-smokers | LT4 | The flow rate calculated in milliliters per minute (under resting conditions in a quiet room between 8 a.m. and 9 a.m.); unstimulated (by expectoration without chewing movements) and stimulated (by chewing a piece of paraffin of identical size, after 60 s of pre-stimulation and swallowing the saliva present in the mouth) whole saliva collected over a period of 5 min in a calibrated and dry plastic tube |
| Chang et al., 2003 [33] | Taiwan | 120 (67/53); 35–75 |
36 (13/23); 37–75 |
HT | History of autoimmune thyroiditis for more than 10 years from the time of diagnosis | Smoking; bad blood sugar control; autonomic neuropathy; immunorheumatic, other endocrine, gastrointestinal, hepatobiliary, renal diseases | Non-smokers | NR | Quantitative salivary scintigraphy after intravenous injection of 5 mCi Tc-99m pertechnetate (including the bilateral parotid and submandibular glands) for 30 min; at 15 min, stimulation with a 200 mg ascorbic acid tablet placed on the dorsal surface of the tongue |
| Changlai et al., 2002 [34] | Taiwan | 40 (17/23); 41–70 |
Xerostomia (−): 36 (13/23); 37–75; Xerostomia (+): 25 (7/18); 35–76 |
HT | History of autoimmune thyroiditis for more than 10 years | Smoking; bad blood sugar control; autonomic neuropathy; immunorheumatic, other endocrine, gastrointestinal, hepatobiliary, renal diseases | Non-smokers | NR | Quantitative salivary scintigraphy after intravenous injection of 5 mCi Tc-99 m pertechnetate (including the four major salivary glands) for 30 min; at 15 min, stimulation with a 200 mg ascorbic acid tablet given orally |
| Coll et al., 1997 [35] | Spain | 176 (152/24); 18–85 (49.3) |
NA | GD, HT | Diagnosed with AITD | NR | NR | NR | Salivary gland scintigraphy |
| Jung et al., 2017 [36] | Republic of Korea | 173 (144/29); 53.3 ± 13.3 |
NA | GD, HT | Symptoms of xerostomia | Drug-induced xerostomia; history of radiation therapy, surgery for head and neck tumors (including thyroid cancer) | NR | NR | Salivary gland scintigraphy after the intravenous injection of 370 MBq Tc-99 m pertechnetate (including the major salivary glands and the thyroid gland) over a 20-min period; then 10 min after the stimulation with a sialagogue the same acquisition time |
| Pang et al., 2021 [37] | China | 32 (32/0); 36 ± 12 |
28 (28/0); 40 ± 12 |
HT accompanied by DTC. | Undergone thyroidectomy for differentiated thyroid cancer; no history of radioiodine treatment; xerostomia symptoms; hypothyroidism at the time of the study | Sjogren’ syndrome or other immunopathy; external radiotherapy to the head and neck; smoking; intake of medications that may cause xerostomia | Non-smokers | Radioiodine treatment preparation with LT4 medication (discontinued for at least one month) | Salivary gland scintigraphy after the intravenous injection of 185 MBq (5mCi) Tc-99 m pertechnetate (including the parotid glands, submandibular glands, and upper neck) over a 15-min period; at 10 min, stimulation with a 300 mg vitamin C tablet placed on the dorsal surface of the tongue |
| Warfvinge et al., 1992 [38] | Sweden | 19 (16/3); 46–61 (54.5) |
12 (8/4); 56–73 (66.8) |
HT | Diagnosed with autoimmune thyroiditis | NR | NR | NR | Unstimulated whole sialometry (abnormal if ≤1.5 mL saliva in 15 min); salivary gland scintigraphy |
Legend: F, females; M, males; AITD, autoimmune thyroid disease; GD, Graves’ disease; HT, Hashimoto’s thyroiditis; NR, not reported; NA, not applicable; DTC, differentiated thyroid cancer; PPD, periodontal probing depth; LT4, levothyroxine.