Hi lucyrf Ford,
The double taxation agreement between the UK and USA, advises that full relief is available for State Pension, Incapacity Benefit and ‘trivial commutation lump sum’.
EIM76009 advises ""There is no liability to income tax in respect of the full amount of any other foreign benefit that is not a taxable foreign benefit if it is substantially similar in character to a UK social security benefit listed in Section 677 Table B ITEPA 2003
Please see EIM76100.
EIM76100 - Social security benefits: list of non-taxable social security benefits
If social security disability insurance has an equivalent non taxable UK benefit, then it would not be taxable in the UK.
The foreign dividends are taxable in the UK and would need to be reported on a self assessment tax return every year.