Nicola Bulley had suffered “significant issues with alcohol” in the past, Lancashire Police said.
The police previously said Nicola is a “high-risk” missing person due to suffering “specific vulnerabilities”, but did not clarify what those were.
A subsequent statement by Lancashire Police said: "Nicola had in the past suffered with some significant issues with alcohol which were brought on by her ongoing struggles with the menopause and that these struggles had resurfaced over recent months.
"This caused some real challenges for Paul and the family," the force said in a reference to Paul Ansell, Nicola’s partner.
They added that a response car with police and health professionals inside “attended a report of concern for welfare” at Nicola’s home on 10 January.
“No one has been arrested in relation to this incident, but it is being investigated”, Lancashire Police said.
The 45-year-old was last seen on Friday 27 January while walking her dog on a footpath by the River Wyre.
Her phone, still connected to a work call for her job as a mortgage adviser, was found just over 20 minutes later on a bench overlooking the riverbank, with her dog running loose.
Since she vanished, huge public and media interest has resulted in what police described as “false information, accusations and rumours” and an “unprecedented” search of both the River Wyre, downstream to Morecambe Bay and miles of neighbouring farmland.
Nearly 40 detectives have sifted through hundreds of hours of CCTV, dashcam footage and tip-offs from the public.
Earlier on Wednesday, Detective Superintendent Rebecca Smith, the lead investigator for Lancashire Police in the case, told reporters at a packed press conference at force HQ: “As soon as she was reported missing, following the information that was provided to the police by her partner Paul, and based on a number of specific vulnerabilities that we were made aware of, Nicola was graded as high-risk.
“It’s normal in any missing person investigation that you obviously gather as much information at an early stage about the person in question, which is no different, and we did that with Paul.
“I’m not going to go into the details of those individual vulnerabilities. I’ve asked you to respect the family, who are going through unimaginable pain and distress at this moment.
“But those vulnerabilities based our decision-making in terms of grading Nicola as high-risk, and have continued to form part of my investigation throughout.”
At that time, police would not be drawn further on the exact nature of Ms Bulley’s “individual vulnerabilities”.
Senior officers were at pains to stress they did not believe anyone had attacked or abducted Ms Bulley, that they believe she had gone into the water without anyone else being involved, and to quash the “persistent myths” around the case.
Assistant Chief Constable Peter Lawson said: “There is no evidence to indicate a criminal aspect or third-party involvement in Nicola’s disappearance.”
The search for Nicola Bulley has become a widescale police operation
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Friends and family of Nicola Bulley are urgently appealing for information
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