This petition was rejected

The Government e-Petitions Team gave the following reason:

Petitions need to call on the Government or Parliament to take a specific action.

We're not sure exactly what you'd like the Government or Parliament to do. The Government's guidance on disability under the Equality Act 2010 states that you’re disabled if you have a physical or mental impairment that has a ‘substantial’ and ‘long-term’ negative effect on your ability to do normal daily activities:
www.gov.uk/definition-of-disability-under-equality-act-2010

It is therefore already the case that under the Equality Act, anyone with a physical or a mental condition which has a substantial and long-term impact on your ability to do normal day to day activities is protected under the disability protected characteristic.

The Personal Independence Payment is paid to people who have a health condition or disability which causes difficulties with daily living or getting around. PIP is paid based on the difficulties causes by a health condition or disability, but there are not particular conditions which result in PIP being paid. You can read more about eligibility for PIP here: www.gov.uk/pip/eligibility

You could start a new petition explaining clearly what you would like the Government or Parliament to do.