Dame Shirley began writing books after she was diagnosed with myalgic encephalomyelitis (ME) in her late 30s and could no longer work full-time.
In 1975, she wrote acclaimed non-fiction book Superwoman, recognised as a feminist practical guidebook.
Dame Shirley’s first novel titled Lace was published in 1982 and later turned into a TV miniseries in the US starring Bess Armstrong, Brooke Adams and Arielle Dombasle.
Her other novels include Savages, Crimson and Tiger Eyes.
Writing on Twitter, Ms Truss posted: “She was a life force, incredibly generous and a dedicated campaigner for maths education.
“I am very grateful for all the encouragement and support she gave me.”
Last week Sir Kenneth Olisa, the Lord Lieutenant of Greater London, presented Dame Shirley with the honour in hospital.
Sharing two pictures from the ceremony, he wrote on social media: “Yesterday Imperial NHS, surrounded by her family and staff of the Manvers Acute Respiratory Unit I was privileged, on behalf of His Majesty, to invest Dame Shirley Conran as a Dame Commander of the Order of the British Empire for services to Mathematics Education.”
