The number of vulnerable adults thought to be at risk of harm or abuse in Glasgow has more than doubled in just three years.

New figures show the numbers referred to social work services by other agencies, including the police, health services and members of the public, have soared since the implementation of the Adult Support and Protection Act in 2008.

A report from the City's Adult Protection Committee submitted to the Scottish Government shows that 1200 adults at risk of possible abuse or mistreatment were referred to social work services in the city during 2009/10. This rose to nearly 1600 in 2010/11, and rose further during 2011/12 when 2633 cases were logged.

The second biennial report from the Glasgow Adult Protection Committee is the first chance experts have had to analyse any changes over time since new laws gave local authorities the power and a duty to make inquiries about the wellbeing or financial affairs of an adult at risk. The rules are designed to protect people whose finances, health or safety could be at risk or who may face exploitation due to infirmity, dementia, learning disabilities or mental health problems, for example.

The committee is now calling for more detailed analysis of the trends their report reveals.

The findings are thought to be similar to those of Scotland's other 28 Adult Protection Committees, each of which has also submitted a report to ministers.

However, the report's lead author and the committee's independent chair Bill Gorman warns that the steep rise in the number of cases considered may not reflect an increase in actual abuse.

"It is a fact that we are seeing a year-on-year increase," he said. "The question is how to explain that.

"It could be that more referrals mean more people are being abused and harmed. Or it could be about better awareness. We can't answer that yet."

Increases could be due to more professionals and members of the public having concerns, he said. It is also notable that despite the high number of referrals, there are a much smaller number of open cases under the Act.

He is concerned, however, that the numbers of people causing concern could be far higher, if awareness of the legislation was better and agencies were more vigilant.

While a high number of referrals (70-80%) are made by police, a small proportion are made by hospital A&E departments. This is surprising because experts in child protection see a high number of cases picked up when children are taken to casualty departments with unexplained injuries.

Meanwhile there appears to be a a wide variation in vigilance of private care homes in the city. While the figuers show a year-on-year increase in the level of referrals from care homes for older people, the bulk of these comes from just 10 care providers.

"Where are all the referrals from other establishments?" Mr Gorman asks.

"The committee has been provided with information that shows a year-on-year increase in the number of referrals from care homes for older people and in particular the concentration of a significant number on a small group of providers."

The fact that the majority of providers is not making referrals is a worry, he suggests. "On a national level there are 30,000 people in Scotland in registered care homes. Our feeling as a society that because someone is in a care home, and subject to 24-hour care, their needs are being taken care of is a falsehood. The Winterbourne View case in England clearly exposed that."

The Act also provided for orders to protect adults deemed at risk, which can be directed at those who might be a danger to them.

There have only been 11 of these in Glasgow since 2009, and of those, five related to one perpetrator.

Mr Gorman says: "The number of orders is not a good measure of the influence of the Act," pointing out that if agencies working with vulnerable people are alert to the risks, orders may not be necessary.

In some cases the low level of reporting from NHS settings could be because that, while cases are picked up in hospital or other settings, police are called and it is police officers who make a referral. However, comparisons with child protection figures suggest this is not sufficient explanation on its own.

"If a child is brought in with a fracture or bruising, that often provokes questions about child protection. We need to look carefully if an adult who is elderly or has learning disabilities is brought into A&E in the same way," points out Mr Gorman.

Detailed statistics in the report allow the way the legislation is being implemented in different parts of the city to be examined, and also shows a breakdown of those affected. Around a third of the cases it covers relates to older people, with those aged 65-plus being disproportionately reflected in the statistics. Meanwhile, one fifth of the cases related to people with addiction problems and self-harm was a prominent problem, featuring in around 25% of all cases.

While 63% of those cases brought to the attention of the committee were from people living in deprived areas, analysts believe older people are in increased need of protection whatever their income. By contrast, adults and children appear to be more likely to need protection the poorer they are.

In a small number of serious cases, there should be a proper review, Mr Gorman adds. While two serious case reviews are currently under way in the city, there are problems in finding staff with the expertise and time to carry them out, he says.

The committee is also asking social workers, the NHS and the care inspectorate to clarify what procedures they have in place for sharing information. It is asking key agencies in social work, the NHS and the Care Inspectorate to do this by February 2013.