GDF15 and diabetes mellitus: Having very high GDF-15 (T3) levels in our study participants was independently associated with an elevated likelihood of having both DM and poor physical function and high GDF-15 (T2) with having DM no poor physical function when no DM no poor physical function was used as reference requires further validation in larger prospective studies taking into account the protective role of metformin which can also be associated with elevated GDF-15 levels [6].