Table 1.

The diagnosis and classification of control groups (unit: case)

Secondary SS	Rheumatic arthritis	5
	Systemic lupus erythematosus	5
	Systemic lupus Erythematosus overlapping with Rheumatic arthritis	2
	Rheumatic arthritis overlapping with polymyoitis	1
	Systemic sclerosis	1
Non-SS	IgG4 related disease	2
	Systemic lupus erythematosus	7
	Rheumatic disease	7
	Askylosing spondylitis	1
	Undifferent connective disease	5
	Mutiple connective disease	2
	Autoimmune hepatitis	1
	Primary biliary cirrhosis	1
	Antiphospholipid syndrome	1
	Diabetes mellitus and gout	1
	Xerostomia	3
	Xerophthalmia	1
	Osteoporosis	1
	Osteoarthritis	3