Financially independant parents can they settle in UK?

Hi,
My parents are financially independent - father is 68 years old and mother is 58 years old. They are settled in Bangladesh at the moment but are financially secure. However both me and my sister live in the UK. I am a British citizen and my sister has Indefinite Leave to Remain (ILR) due to apply for citizenship next year. We both would like to bring our parents here. I am married and have a child and it would be nice for my daughter to have her grandparents around growing up as my wife’s parents are sadly no more. Is there any way I can sponsor to bring my parents over? My father suffers from depression and there are not many good psychological treatment facilities he can benefit from in Bangladesh but in the UK there seems to be a lot more options. It is common for many retired men to go through depression at an elderly age and being close to his family and his grandchild would be beneficial to him so I am wondering if there is any option for us to bring them to the UK to live here permanently? Thank You.

Not under the new rules unfortunately. These are the strict requirements which it seems your parent's situation doesn't meet;
You must prove that:
you need long-term care to do everyday personal and household tasks
the care you need is not available or affordable in the country you live in
the person you’ll be joining in the UK will be able to support, accommodate and care for you without claiming public funds for at least 5 years
you’re 18 or over