# Prevalence of Interstitial Lung Disease in Patients with Primary Sjogren’s Syndrome: A Systematic Review and Meta-analysis of Observational Studies: Prevalence of Interstitial Lung Disease in Patients with Primary Sjogren’s Syndrome

## TL;DR

This study finds that about 23.5% of patients with primary Sjogren’s syndrome have interstitial lung disease, with notable differences by gender and age.

## Contribution

The study provides a meta-analysis of observational data to quantify the prevalence of interstitial lung disease in primary Sjogren’s syndrome patients.

## Key findings

- The overall prevalence of ILD in primary Sjogren’s syndrome patients is 23.5%.
- The most common type of ILD is non-specific interstitial pneumonia (NSIP) at 48.8%.
- Prevalence is higher in men (45.5%) compared to women (31.2%).

## Abstract

Interstitial Lung Disease (ILD) is the most common pulmonary manifestation in
patients with primary Sjögren’s syndrome. Therefore, this study aimed to
investigate the prevalence of ILD in patients with primary Sjögren’s
syndrome (pSS) using a systematic review and meta-analysis method.

This study searched databases ProQuest, PubMed, Web of Science, Cochrane,
Embase, and the search engine Google Scholar until February 8, 2025. Studies
were combined using the sample size and variance of each study. The
heterogeneity of the studies was examined using the Q Cochrane test and the
I2 index. The significance level of the tests was considered P0.05.

34 observational studies, with a total of 9535 individuals, showed that the
prevalence of ILD in all patients with pSS was 23.5% (95%CI: 18.6%, 28.4%),
in women 31.2% (95%CI: 18.4%, 44.1%), and in men 45.5% (95%CI: 23.6%,
67.4%). Moreover, the prevalence of ILD in patients with pSS in the age
group of 30 to 39 years was 22.2% (95%CI: 18.9%, 26%), 40 to 49 years 10.8%
(95%CI: 8.7%, 12.9%), 50 to 59 years 27.6% (95%CI: 17.9%, 37.4%), and 60 to
69 years 23.3% (95%CI: 17.9%, 28.7%). Also, the prevalence of ILD in
patients with pSS in case-control studies was 15.6% (95%CI: 7.1%, 24.1%), in
cohort studies 25.7% (95%CI: 19%, 32.4%), and in cross-sectional studies
21.4% (95%CI: 11.9%, 31%). However, the prevalence of non-specific
interstitial pneumonia (NSIP) was 48.8% (95%CI: 41.4%, 56.2%), usual
interstitial pneumonia (UIP) 15% (95%CI: 10.5%, 19.5%), LIP 10.8% (95%CI:
6.6%, 15%), and organizing pneumonia (OP) 9.4% (95%CI: 5.4%, 13.4%).

One out of every four patients with pSS has ILD, and the prevalence of ILD
was higher in men than in women. Moreover, the most common type of ILD was
NSIP, followed by UIP, OP, and LIP, and the highest prevalence of ILD was in
the age group of 50 to 59 years. Evaluating further studies regarding the
impact of various factors on ILD can help in better diagnosing it in
patients.