Is Helicobacter pylori the usual suspect behind gastroesophageal reflux disease and dacryostenosis?

Lacrimal Drainage Obstruction and Gastroesophageal Reflux Disease: A Nationwide Longitudinal Cohort Study

GOALS

This study aimed to evaluate the association between gastroesophageal reflux disease (GERD) and development of lacrimal drainage obstruction (LDO).

BACKGROUND

It has been hypothesized that GERD may contribute toward the development of LDO.

STUDY

This was a retrospective study of Koreans aged 40 to 79 years registered in the Korean National Health Screening Cohort from 2002 to 2013. Incident cases of LDO were identified according to the Korean Classification of Disease. We compared hazard ratios (HRs) for LDO between 22,570 patients with GERD and 112,850 patients without GERD by 1:5 propensity score-matched analysis.

RESULTS

A total of 135,420 patients, representing 1,237,909 person-years, were evaluated. LDO developed in 1998 (8.9%) patients with GERD and 8565 (7.6%) patients without GERD (P<0.001). The incidence of LDO per 1000 person-years in patients with GERD was 9.7 and 8.3 in those without GERD; the age-adjusted and sex-adjusted HR was 1.17 (95% confidence interval, 1.11-1.23). This association between GERD and LDO was more pronounced among younger individuals (HR, 1.20 for patients 40 to 59-y old; HR, 1.12 for patients 60 to 79-y old) and among men (HR, 1.20 for men; HR, 1.14 for women). Patients with GERD had a higher risk of LDO than those without GERD, irrespective of history of proton-pump inhibitor use. In the sensitivity analysis, GERD patients with esophagitis had a higher risk of LDO than those without esophagitis.

CONCLUSIONS

Our findings suggest that GERD is associated with an increased risk of subsequent LDO and that this effect is more pronounced among adults aged 40 to 59-years old and men.

A proposed role of human defensins in Helicobacter pylori-related neurodegenerative disorders

Cationic host defence peptides (CHDPs), also known as antimicrobial peptides (AMPs), are essential components of the innate immunity with antimicrobial and pleiotropic immunomodulatory properties. In mammals the two major families of CHDPs are defensins and cathelicidins that comprise an arsenal of innate regulators of principal importance in the host tissues. Research in the last decade has demonstrated that defensins are crucial effectors of both innate and adaptive immunity. Defensins can modulate immune responses, either by stimulation or suppression, thereby controlling inflammatory processes and infections. Currently only few data, mostly hypothetical, focus on the role of defensins in central nervous system (CNS) physiopathology and neurodegeneration. Defensins may function as an initial line of defense within the CNS either as an antimicrobial, immunomodulator, or both. A dysregulation of brain expression of specific defensins might either exacerbate or ameliorate the inflammatory response within the CNS depending upon which extracellular conditions predominate. It is proposed that reduction or abnormal elevation of AMP expression by cerebral microglia, astrocytes or choroid plexus epithelium might contribute to loss of AMP-induced regulation of immune responses, thereby promoting neuronal cell injury and death observed in Alzheimer's disease and possibly in other neurodegenerative disorders. Nevertheless, whether certain AMPs play a crucial role in the onset or promotion of the neuroinflammatory process and neurodegeneration is currently unknown, thereby emphasizing the necessity of further investigation into the regulatory mechanisms that control innate and adaptive immunity within the brain. Recent data indicate that Helicobacter pylori (H. pylori) induces defensins' release associated with chronic inflammatory tissue damage. However, it remains unclear whether and how H. pylori evades the attack by defensins. Moreover, recent evidence indicates that H. pylori infection might contribute to the pathogenesis of neurodegenerative diseases, by releasing several inflammatory mediators that could induce blood-brain barrier breakdown, thereby being involved in the pathogenesis of neurodegeneration. However, currently there are no data regarding the potential impact of human defensins on H. pylori-related neurodegenerative disorders. We herein propose that human defensins might contribute to the pathophysiology of H. pylori-related neurodegenerative disorders by modulating variably innate and adaptive immune system responses. Better understanding of the mechanisms regarding human defensins' possible involvement in H. pylori-induced neurodegeneration might help develop novel therapeutic strategies against H. pylori-related neurodegenerative disorders.