The Role of the Neutrophil-to-Lymphocyte Ratio and Platelet-to-Lymphocyte Ratio as Markers of Disease Activity in Ankylosing Spondylitis.

Background Ankylosing spondylitis (AS) is a chronic rheumatological condition affecting sacroiliac joint and spine and occurs more often in younger patients than in the elderly population. Objective The purpose of the study was to determine the association of the neutrophil-lymphocyte ratio (NLR) and platelet-lymphocyte ratio (PLR) with the disease activity of AS. Methodology This case-control study was conducted in the rheumatology department at the Pakistan Institute of Medical Sciences (PIMS) hospital in Islamabad from September 2018 to July 2019. The study consisted of two groups of 59 patients per group. We assessed a full blood count with erythrocyte sedimentation rate (ESR) for each participant using the PIMS hospital laboratory. NLR and PLR were calculated. Results The mean age of the participants in the control group and the cases group was the same (32 ± 4 years). The control group NLR was 1.30 ± 0.16, the PLR was 94.98 ± 17.96, and the ESR was 16.88 ± 3.76 mm/hour. For the cases group, the NLR was 3.08 ± 0.91, the PLR was 171.50 ± 38.06, and the ESR was 29.30 ± 9.20 mm/hour. There was a significant increase in cases for NLR, PLR, and ESR as compared to control samples (p<0.05). The mean Bath Ankylosing Spondylitis Disease Activity Index (BASDAI) score of participants with active diseases was 5.91±1.28. In the same group, the mean ESR was 27.65 ± 9.07 mm/hour, the NLR was 3.46 ± 0.80, and the PLR was 184.39 ± 36.13. For those in the inactive disease group, the mean BASDAI score was 2.84 ± 0.46, the ESR was 33.42 ± 8.48 mm/hour, the NLR was 2.17 ± 0.37, and the PLR was 139.71 ± 26.05. NLR and PLR were significantly higher in the active disease group (p<0.05). Conclusion NLR and PLR are good markers of inflammation in AS patients, and higher values indicate more active disease activity.