THE cause of death of a college cleaner who was found unresponsive in her home is still unknown, an inquest has heard.

Susan Smith, 68, was found dead in her flat in Headley Way, Headington, on Monday, January 15 after last being seen by her neighbour four days prior.

Her daughter, who had last received a message back from her mum before the weekend, found Ms Smith face down in her kitchen.

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An inquest was held into the college cleaner’s death at Oxford Coroner’s Court on Monday (June 24) where it was heard that a medical cause of death is listed as ‘unascertained’.

Area coroner Nicholas Graham said there is ‘limited evidence’ to what may have caused her death, ruling out morphine poisoning and chronic obstructive pulmonary disease (COPD) as ‘unlikely’.

Inquests are held at Old County Hall He provided a narrative conclusion which included the circumstances surrounding her death.

During the inquest, it was heard that Ms Smith had been suffering from consistent pins and needles in her hands and feet which was causing her pain from December.

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She had called her GP and was referred to the medical team at the John Radcliffe Hospital.

Ms Smith was prescribed morphine tablets which were later increased in January after the symptoms continued.

In a toxicology report taken during the post-mortem examination, it was discovered that Ms Smith had 1,000ng/l of morphine in her blood which ‘could be considered excessive depending on the tolerance’ of the user.

The pathologist stated they could ‘not rule out’ morphine poisoning as a cause of death.

However, coroner Mr Graham told the inquest that Ms Smith’s GP believed morphine poisoning was ‘unlikely’ due to her having taken the medication for a while meaning she would have slowly built up a tolerance.

During the post-mortem examination, it was also established that she had a ‘small bruise’ on the front of her head but no fractures or haemorrhages meaning a potential fall being the cause of death was also considered unlikely.

A statement from police officers who attended her home also concluded that there were ‘no signs of a disturbance’ and ruled out a potential burglary.

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Writing about her mum, Ms Smith’s daughter said: “She was generally a poorly lady but tried her best not to let it get her down.

“She loved popping out every day on the bus to go to the shops and also used to go on organised holidays.”

Concluding the inquest, Mr Graham said: “There are very distressing circumstances and I don’t think there’s anything I can say to give much comfort.”