The results are supported by an RCT in 80 infants with heart failure [41] and mean 25OHD levels of 35 nmol/L, in which treatment with 1000 IU vitamin D daily suppressed PTH levels, the proinflammatory cytokines interleukin-6 and tumor necrosis factor-α, and increased the anti-inflammatory cytokine interleukin-10 as well as left ventricular ejection fraction significantly. Here, PTH is linked to heart failure.