Evidence-based nutritional and pharmacological interventions targeting chronic low-grade inflammation in middle-age and older adults: A systematic review and meta-analysis

• Published in: Ageing research reviews Vol. 46; pp. 42 - 59
• Main Authors: Custodero, C, Mankowski, R T, Lee, S A, Chen, Z, Wu, S, Manini, T M, Hincapie Echeverri, J, Sabbà, C, Beavers, D P, Cauley, J A, Espeland, M A, Fielding, R A, Kritchevsky, S B, Liu, C K, McDermott, M M, Miller, M E, Tracy, R P, Newman, A B, Ambrosius, W T, Pahor, M, Anton, S D
• Format: Journal Article
• Language: English
• Published: England 01-09-2018
• Subjects: Nutrient; Adults; C-reactive protein; Pharmaceutical; Chronic inflammation; Interleukin-6
• ISSN: 1568-1637; 1872-9649
• DOI: 10.1016/j.arr.2018.05.004

Growing evidence suggests chronic low-grade inflammation (LGI) as a possible mechanism underlying the aging process. Some biological and pharmaceutical compounds may reduce systemic inflammation and potentially avert functional decline occurring with aging. The aim of the present meta-analysis was to examine the association of pre-selected interventions on two established biomarkers of inflammation, interleukin-6 (IL-6), and C-reactive protein (CRP) in middle-age and older adults with chronic LGI. We reviewed the literature on potential anti-inflammatory compounds, selecting them based on safety, tolerability, acceptability, innovation, affordability, and evidence from randomized controlled trials. Six compounds met all five inclusion criteria for our systematic review and meta-analysis: angiotensin II receptor blockers (ARBs), metformin, omega-3, probiotics, resveratrol and vitamin D. We searched in MEDLINE, PubMed and EMBASE database until January 2017. A total of 49 articles fulfilled the selection criteria. Effect size of each study and pooled effect size for each compound were measured by the standardized mean difference. I
was computed to measure heterogeneity of effects across studies. The following compounds showed a significant small to large effect in reducing IL-6 levels: probiotics (-0.68 pg/ml), ARBs (-0.37 pg/ml) and omega-3 (-0.19 pg/ml). For CRP, a significant small to medium effect was observed with probiotics (-0.43 mg/L), ARBs (-0.2 mg/L), omega-3 (-0.17 mg/L) and metformin (-0.16 mg/L). Resveratrol and vitamin D were not associated with any significant reductions in either biomarker. These results suggest that nutritional and pharmaceutical compounds can significantly reduce established biomarkers of systemic inflammation in middle-age and older adults. The findings should be interpreted with caution, however, due to the evidence of heterogeneity across the studies.