Kid­ney fail­ure is such a cat­a­stroph­ic (and expen­sive) dis­ease that Medicare cov­ers treat­ment for any­one, regard­less of age. Since Medicare reim­burse­ment rates are fair­ly low, the dial­y­sis indus­try had to find a way to tweak the sys­tem if they want­ed to make big prof­its. They succeeded.