The man allegedly bought earplugs from Bunnings so he could sleep through the screams, court documents say.
In a pre-trial committal hearing in the Melbourne Magistrates Court on Thursday, forensic pathologist David Ranson said the woman had suffered a stroke, but was unable to pinpoint when.
He said she most likely died from aspirating on food after losing the ability to swallow properly following the stroke.
Dr Ranson, who conducted the autopsy, in court documents noted insect eggs were found in the corner of one of her eyes, that she weighed only 34kg, and that a "large number" of skin sores and scabs were present on her body.
Geriatrician Joseph Ibrahim also gave evidence on Thursday, telling the court the woman had previously attended GPs on a monthly basis, a habit that fell away after 2010.
In court documents, he noted that according to family members, six months previously the woman had stopped taking epilepsy medication "because of mood swings" and had many falls.
The pair will reappear in court for a directions hearing on Friday.