IL1B and chronic obstructive pulmonary disease: Subgroup analyses showed both Sprague Dawley rats (SMD = -2.26 95% CI: -3.76 to -0.76, z = -2.946, p = 0.003 < 0.05) and C57B1/6 mice (SMD = -4.85, 95% CI: -6.44 to -3.27, z = -5.998, p = 0.000 < 0.05) displayed probiotics significantly decreased IL-1β in COPD animals.