[13] Further, vitamin D has been reported to attenuate inflammation in periodontal tissue induced by Porphyromonus gingivalis, again a strong triggering event for development of RA.[14] Such associations of low vitamin D state with many other systemic autoimmune diseases, including lupus, are also well known and readers will have no difficulty in finding selleckchem enough, and convincing, publications in this regard.[15, 16] Apart from its osteoimmunological implications, vitamin D deficiency and the renin angiotensin system (RAS) activity may represent two sides of the same

coin which is responsible for metabolic syndrome and high cardiovascular mortality, as hypothesized and reported by some.[17] This is all the more relevant as vitamin D is also reported to have a protective role against metabolic syndrome in RA.[18] An inverse relationship between vitamin D levels and C-reactive protein is yet another factor in imparting cardiovascular protection in RA.[19] In contrast, there is a query if vitamin D levels should be tested indiscriminately for every ache and pain in rheumatology and this was addressed in a study from Kuwait published in this issue of IJRD. While the authors report otherwise in this study, there are some elements of truth in the other school of thought too. Most of these studies have methodological flaws, heterogeneous cohort, smaller sample

size and are underpowered to address this issue. However, the majority of the reports from different populations have documented lower vitamin D levels in vague aches and pain than reference populations.[20-22] Correlation between low back pain in people learn more with modic changes and vitamin D insufficiency also

do exist in the literature.[23] A randomized controlled trial conducted among non-Western immigrants with nonspecific musculoskeletal pain in the Netherlands suggests modest benefit of vitamin D.[24] Low Ketotifen vitamin D state in a cohort of fibromyalgia patients and good response to corrective treatment have been documented both in veiled, conservatively dressed, as well as in non-veiled subsets alike.[25] Even in the elderly, post-menopausal, as well as in mixed cohorts of patients with different rheumatic diseases, vitamin D showed clear improvement in musculoskeletal pain[26-28] and negative studies have been reported only occasionally.[29] To add further, vitamin D deficiency leading to hypersensitivity to pain in muscles via nerve endings has been described.[30] And finally, what is non-specific musculoskeletal pain (NSMP)? Is it a harbinger of evolving early inflammatory arthritis at least in a subset of patients, especially in view of its strong association with deficiency of vitamin D in many studies? Can the onset of inflammatory arthritis be delayed by treating a low vitamin D state in this setting? These questions have no answers at this moment.