The singer and actress died in her home city of Fremont in California following years of crack cocaine abuse .
Ms Matthews, who was a protege of pop icon Prince, had several hits in the early 1980s as lead singer of the group Vanity 6.
Her friend MC Hammer tweeted last night: "She absolute loved God unto salvation.
I sing to Jesus for Jesus now. This gives me pure joy ... worship!
"She fell ill during the night [and] ended up on life support."
Ms Matthews, who began her career as a model, met Prince backstage at the American Music Awards in 1980, and the pair started a romantic relationship.
Her biggest hit was 1982’s “Nasty Girl”, which is a synth-funk single with very sexual lyrics.
It has now become a dance floor classic.
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Ms Matthews signed with Motown Records in 1984, under which she released two solo records, Wild Animal and Skin on Skin.
She also embarked on an acting career, which saw her star in the Last Dragon in 1985.
She had a reputation as a hard partier in her early years of fame, which included various rocker boyfriends and she developed a dangerous addiction to crack cocaine.
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Following a near-fatal renal failure, she became sober and a born-again Christian.
She had a kidney transplant in 1997.
In an interview with Rolling Stone last year, Vanity said: "I don't listen to my old music of Vanity's unless I have to hear it playing in a mall or something place like that.
"I sing to Jesus for Jesus now. This gives me pure joy ... worship! I apologize profusely to those I have offended deeply a million times over."
Last year, she was diagnosed with sclerosis encapsulating peritonitis, a severely painful kidney condition.
She set up a crowdfunding effort to pay for her treatment and raised $6,599 of the $50,000 she had sought.