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Published on: June 26, 2018
Platelet to Lymphocyte Ratio in Polymyositis as a Marker of Disease Activity
Background:
Platelet to lymphocyte ratio (PLR) has been regarded as a parameter in assessing systemic inflammation. Polymyositis (PM) is a rare connective tissue diseases characterized by chronic muscle inflammation, which led to a hypothesis with respect to PLR in PM patients. Therefore, it is reasonable to investigate the relationship between PLR and PM.
Methods:
The present study included 46 newly diagnosed PM patients and 128 healthy subjects as controls. The muscle weakness of PM patients was measured using the manual muscle test (MMT) to evaluate disease activity in patients with PM.
Results:
Neutrophil to lymphocyte ratio (NLR) and PLR were higher in patients with PM compared with healthy controls (4.1 ± 1.32 vs. 1.6 ± 0.58, p < 0.001, 158.4 ± 86.39 vs. 103.8 ± 29.82, p < 0.001). PLR was positively correlated with NLR, ESR, and platelet counts (r = 0.392, p = 0.008, r = 0.422, p = 0.020, r = 0.366, p < 0.001), and negatively with lymphocyte counts (r = -0.872, p < 0.001) in patients with PM. Interesting, a reverse correlation between PLR and MMT score was observed in patients with PM (r = -0.383, p = 0.010). However, there was no correlation between NLR and MMT score (r = -0.266, p = 0.074). In logistic regression analysis, PLR was independently associated with PM after adjustment for age, gender, ESR, lymphocyte counts, neutrophil counts, leukocyte counts, and NLR. The resulting odds ratio (OR) and 95% confidence interval (95% CI) were 1.017 (95% CI 1.003 - 1.031; p = 0.015) for PLR.
Conclusions:
Our research suggests that PLR is associated with PM, and PLR may be used to estimate disease activity of PM patients.
Insights
The platelet to lymphocyte ratio (PLR) is elevated in polymyositis (PM) patients and correlates with disease activity. This suggests PLR can help assess systemic inflammation and disease severity in PM.
Area of Science:
- Rheumatology
- Immunology
- Biomarkers
Background:
- Systemic inflammation is a key feature in autoimmune diseases.
- Polymyositis (PM) is a rare inflammatory myopathy.
- The platelet to lymphocyte ratio (PLR) is an emerging marker for systemic inflammation.
Purpose of the Study:
- To investigate the association between PLR and polymyositis (PM).
- To explore the utility of PLR in assessing disease activity in PM patients.
Main Methods:
- A case-control study involving 46 newly diagnosed PM patients and 128 healthy controls.
- Muscle weakness assessed using the Manual Muscle Test (MMT).
- Statistical analysis including correlation and logistic regression.
Main Results:
- PM patients exhibited significantly higher PLR and Neutrophil to Lymphocyte Ratio (NLR) compared to controls.
- PLR positively correlated with NLR, ESR, and platelet count, and negatively with lymphocyte count.
- A significant inverse correlation was found between PLR and MMT scores, indicating higher PLR with greater muscle weakness.
Conclusions:
- PLR is significantly associated with polymyositis (PM).
- PLR may serve as a valuable biomarker for estimating disease activity in PM patients.
