Tests were expected to find the BBC daytime host suffocated while deliberately starving himself of oxygen to heighten sexual arousal.
The extremely dangerous practice of auto-erotic asphyxiation is said to increase sexual pleasure and participants employ masks, ligatures or even plastic bags to achieve the desired effect.
Officers said they were officially treating the circumstances of his death as "unexplained".
In a statement his relatives said: "The family are saddened and in a state of shock at the loss of Kristian who they loved very much."
Digby was pronounced dead at his home in Richford Road, Newham, east London, after an ambulance crew was called shortly before 8am yesterday.
Colleagues and friends have reacted with shock, describing the To Buy Or Not To Buy host as a "lovely guy" who brought a "real sense of energy and warmth to all the shows he presented".
Liam Keelan, Controller of BBC Daytime, said the 32-year-old would be "very much missed".
"Kristian was without doubt one of the most popular and talented presenters on BBC Daytime," he said.
"He cared passionately about the programmes he presented and viewers loved the charm and warmth he brought to every one of his shows.
"He will be very much missed by all those who knew him. Our thoughts are with his family at this very sad time."
The property expert worked on a string of shows including Double Agents, Living In The Sun, House Swap and Buy It, Sell It, Bank It.
Digby's agent and friend Jo Wander said: "I am devastated by the loss. He was a lovely guy and a very talented presenter and director.
"I will miss him hugely and my thoughts at this time are with his family and his many friends. He will be sorely missed."
A BBC spokesman said: "Kristian was a much-loved and talented presenter for BBC Daytime.
"He brought a real sense of energy and warmth to all the shows he presented for us and will be sorely missed. Our thoughts are with his family at this very difficult time."
Neighbour Shirley Shannon, 64, said Digby moved in around 10 years ago.
It is believed that after initially living in an end-of-terrace two-storey house, he built and moved into his "dream home" in land adjacent to the property.
Ms Shannon said: "He said to us it was his dream home and we joked 'How can it be your dream home when you've built it in your own garden?'," Ms Shannon said.
A neighbour told of the work he did to improve life for people in the area.
He said Digby arranged for trees to be planted along the street and rubbish to be collected.
He added: "He made it look nice. Everybody knew him. It is a sad loss."
Digby presented the BBC's Holiday Show and was the series director on The Million Pound Property Experiment for BBC2.
He also directed films and television programmes. He won a junior Bafta in 1997 for his short film Words Of Deception and directed programmes such as Home Front, Fantasy Rooms, She's Gotta Have It, Girls On Top and The Ozone.
A Scotland Yard spokesman said: "Police were called to reports of a body of a man in his 30s found at an address in Richford Road, E15.
"Ambulance services attended and life was pronounced extinct. Next of kin were informed and we await formal identification."
Despite being condemned by police and medical experts, auto-erotic asphyxiation continues to claim lives.
Kill Bill film star David Carradine and INXS singer Michael Hutchence died in similar circumstances, although questions remain over their final moments.
A Metropolitan Police spokeswoman said the results of a post-mortem examination were "inconclusive" and officers await further tests.
She said: "An inquest will be opened and adjourned in due course. The death is still being treated as unexplained.
"We await formal identification. We are satisfied there was no third-party involvement."
