Title:Aging and immunopathology in primary Sjögren's syndrome
VOLUME: 8 ISSUE: 2
Author(s):Hjalmar R. Bouma, Hendrika Bootsma, Jolien F. van Nimwegen, Erlin A. Haacke, Fred K. Spijkervet, Arjan Vissink and Frans G.M. Kroese
Affiliation:Department of Rheumatology & Clinical Immunology, University of Groningen, University Medical Center Groningen, Hanzeplein 1 (AA21), 9713 GZ, Groningen, The Netherlands.
Keywords:Aging, autoimmunity, autophagy, inflammation, lacrimal gland, salivary gland, sjögren’s syndrome, xerostomia.
Abstract:Sicca complaints (sensation of dry mouth and/or eyes) are present in about a quarter of the individuals above
the age of 65 years old and are mainly due to medication. However, physiological changes that occur during aging might
also lead to a diminished glandular function. These age-related changes are, at least in part, to be the consequence of decreased
androgen levels. In addition to these physiological effects that occur during normal aging, sicca complaints can
also be caused by Sjögren’s syndrome (SS): a systemic auto-inflammatory disorder mainly affecting exocrine glands. Genetic
factors, lowered levels of gonadal hormones and (viral) infections appear to contribute to the etiology of the syndrome.
The incidence of SS is higher among aged individuals, which might be due to earlier diagnosis, as the onset of SS
in an individual with age-related exocrine gland dysfunction lowers the threshold for sicca complaints. On the other hand,
physiological aging might be considered as a risk factor for development of SS, resulting in a faster development of the
syndrome. Differentiating physiological sicca complaints from SS in the elderly can be challenging, since apparently
healthy individuals might present with auto-antibodies and lymphocytic infiltrates in salivary glands might be present as
well. The drop in the level of androgens and estrogens upon aging, immunosenescence and pro-inflammatory features of
the aging immune system may all contribute to the etiology of pSS in the elderly. In this review, we describe the physiological
effects of aging and the influence of SS on exocrine gland morphology and function.