Abstract
Purpose :
Exfoliation syndrome (XFS) is a complex, inherited disorder of extracellular matrix (ECM) metabolism characterized by an accumulation of fibrillary material in many tissues. XFS has a strong genetic association with the LOXL1 locus. LOXL1 is widely expressed in connective tissues containing elastin, and integral to elastin synthesis. XFS appears to be associated with dysregulated connective tissue repair and may contribute to progressive weakening and tissue failure, recently reported in pelvic organ prolapse (POP) (Wirostko et al Jama, 2016). We addressed the hypothesis that XFS may similarly increase susceptibility to a similar condition, IH, in male patients in the Utah Population Database (UPD).
Methods :
International Classification of Diseases, 9th Revision (ICD-9) diagnosis and Current Procedural Terminology (CPT) codes in medical records linked to the UPD were used to identify subjects in a large healthcare system with a diagnosis of XFS (365.52 and 366.11) and/or IH (ICD9: 17.1, 53.0-53.1, 550; CPT: 49505, 49507, 49520-21, 49525, 49650-51). Unconditional logistic regression models adjusted for age, race/ethnicity, BMI, and smoking status estimated the risk of XFS in males age > 40 on 1/1/1996 (when electronic records became available) with an IH diagnosis compared to 5:1 age-matched controls using a cross-sectional approach.
Results :
Of 2,419 male patients identified with IH (385 direct inguinal, 454 indirect inguinal, and 1580 undetermined inguinal hernia), 27 patients had an XFS diagnosis. Of 12,092 controls, 60 subjects had an XFS diagnosis. Subjects with indirect inguinal hernia had a 3.35-fold risk for an XFS diagnosis compared with controls (95%CI=1.04-10.80, p<0.04). The risk of IH in all subjects was 2.23-fold for patients with an XFS diagnosis (95%CI=1.39-3.76, p=0.001) compared to those without an XFS diagnosis. There was no association with XFS and direct inguinal hernia.
Conclusions :
An XFS diagnosis appears to increase risk for IH in men in this UPEXS study. We previously reported that XFS increases risk of POP in women, another systemic connective tissue disorder. Risk for both of these conditions may be secondary to altered ECM and elastin metabolism. Further work is needed to better understand the pathophysiology of these diseases and to determine the contributions made by genetic, environmental, and molecular factors related to XFS.
This is an abstract that was submitted for the 2017 ARVO Annual Meeting, held in Baltimore, MD, May 7-11, 2017.