Graeme McLaren, who skewered James Small with the walking aid at his flat in Weir Street, Greenock, leaving him with horrific internal injuries in June this year, was jailed for life by Judge Rita Rae, QC.
At his trial at the High Court in Glasgow, McLaren sought to smear the character of his victim by making false sexual allegations about him.
Judge Rae told McLaren, 47, from Greenock: "You have been convicted unanimously of a most brutal and depraved attack on a defenceless and vulnerable elderly man. Not satisfied with this, you set out to blacken his character with false allegations.
"This was inflicted in a most demeaning way and you put him in fear of being reported to the police for a wholly fabricated offence. Mr Simpson died in agony and alone. He must have been in excruciating pain.
"You have done your best to blacken the character of the deceased and made a serious, but false allegation against him and have shown no remorse."
Mr Simpson died days later in his flat after the assault by McLaren who then boasted and joked about what he had done.
On Monday a jury unanimously found McLaren guilty of murder. During a trial at the High Court in Glasgow, McLaren, 47, of Greenock, denied attacking his neighbour Mr Small on June 5 this year.
Mr Small suffered damage to his bowel and liver. Pathologist Dr Julie McAdam said that considerable force would have been used to inflict the injuries.
Advocate depute Douglas Fairley, QC, told the court McLaren had a catalogue of previous convictions including violence, drug dealing and carrying weapons.