HP and type 2 diabetes mellitus: During COVID-19, T2DM was associated with a significant and very early increase in haptoglobin in patients younger than 20 years of age compared with non-T2DM patients, both in women (0.25 g/L vs 0.12 g/L) and men (0.14 g/L vs 0.02 g/L) (Figure 17).