Greater numbers of the innate immune cells known as neutrophils are characteristic of inflammation, whether transient or chronic. A complete blood count of different immune cell populations in circulation can be used to derive the neutrophil to lymphocyte ratio, and this can be used as a measure of chronic inflammation in older individuals. While there is a lot of variety from individual to individual, on balance either significantly more neutrophils than the average (common) or significantly fewer lymphocytes than the average (uncommon) indicates a worse prognosis for health in the years ahead. Chronic inflammation is disruptive to tissue structure and function, and drives the onset and progression of all of the major age-related conditions, including the progressive loss of muscle mass leading to sarcopenia. Thus one might expect to see correlations like the one noted here, between pace of muscle loss and neutrophil to lymphocyte ratio in older individuals.
Inflammation plays a pivotal role in the age-related decline of skeletal muscle mass, leading to sarcopenia in the elderly. The prevalence of sarcopenia notably increases among males aged ≥ 70. However, it remains unclear whether inflammatory indexes are associated with the reduction in skeletal muscle mass in the elderly population. Thirty-one males aged ≥ 70, without severe diseases or dementia, were enrolled in the study. They underwent muscle mass measurements, physical measurements, and hematological tests at the onset of the study and after a one-year follow-up.
Twenty-eight participants were successfully followed for one year. Appendicular skeletal muscle mass index (ASMI) decreased by 3.30 ± 2.41% in 14 participants and increased by 2.66 ± 1.61% in the other 14 participants compared to baseline levels. The baseline neutrophil-to-lymphocyte ratio (NLR) was 2.14 ± 0.56 in the ASMI-decreased group and 1.66 ± 0.62 in the ASMI-increased group. A statistically significant negative correlation was found between baseline NLR and the change in ASMI in linear regression analyses. NLR emerged as a potential prognostic marker for ASMI reduction in elderly males. However, further studies are necessary to assess its clinical utility.
Link: https://doi.org/10.18632/aging.206217
View the full article at FightAging