The terms "medically determinable physical or mental impairment" and
"substantial gainful activity" shall have the meanings ascribed to them in the
federal Social Security Act, as now or hereafter amended, and the
regulations issued thereunder.
The disability retirement annuity payment period shall begin immediately
following the expiration of the disability benefit payments under clause
(6) of Section 15-152 and shall be discontinued for a recipient of a disability retirement annuity when (1) the physical or
mental impairment no longer prevents the participant from engaging in any
substantial gainful activity, (2) the participant dies or (3) the participant
elects to receive a retirement annuity under Sections 15-135 and 15-136.
If a person's disability retirement annuity is discontinued under clause
(1), all rights and credits accrued in the system on the date that the
disability retirement annuity began shall be restored, and the disability
retirement annuity paid shall be considered as disability payments under
clause (6) of Section 15-152.
(Source: P.A. 97-933, eff. 8-10-12; 97-968, eff. 8-16-12.)