A comparison of salivary gland hypofunction in primary and secondary Sjogren's syndrome

OBJECTIVE: A commonly held view by clinicians is that the salivary gland hy pofunction associated with primary Sjogren's syndrome (SS-I) is more severe than that associated with secondary Sjogren's syndrome (SS-2), This study aimed to determine if this view could be substantiated, when applied to a l arge sample group. METHOD: Unstimulated and paraffin wax-stimulated whole salivary flow rates were retrospectively compared for age and gender matched, patients diagnose d with SSI or SS-2 according to the preliminary European criteria, The pati ents bad attended the Xerostomia Clinic, in the Oral Medicine Department, a t the Liverpool University Dental Hospital. RESULTS: Sixty-seven patients with SS-I (average age 57.1 years) were match ed with 67 patients with SS-2 (average age 57.6 years), according to gender and age, within 5 years, The mean unstimulated whole salivary flow rates ( +/-s.d.) for patients with SS-I and SS-2 were 0.11 (+/-0.15) and 0,12 (+/-0 .18) mL min(-1) respectively, The mean paraffin wax stimulated, whole saliv ary flow rates (+/-s.d.) for patients with SS-I and SS-22 were 0.45 (+/-0.0 2) and 0.47 (+/-0,49) mL/ min(-1) respectively. No significant differences, in either stimulated (P = 0.54) or unstimulated (P = 0.60) whole salivary flow rates were found between individuals with SS-I or SS-2, CONCLUSION: The severity of salivary gland hypofunction does not appear to be related to the clinical variant of Sjogren's syndrome.