Mass affluent Americans have become much more worried about their retirement preparations over the last five years, but remain hesitant about investing in the stock market as a way of achieving required capital growth, the latest research by Prudential shows.

According to the survey, 2006 to 2011: Changing Attitudes About Retirement Income, six in ten people are concerned about how much income they will need when they retire. Compared with just 11 per cent in 2006, over half (56 per cent) now question whether their retirement strategies are sufficient to reach their goals, while 68 per cent said they are more cautious than ever before. The respondents were part of "The Retirement Red Zone," or those aged within the critical years before and after retirement.

Meanwhile, 47 per cent remain hesitant to enter the stock market, with 60 per cent saying that investing too aggressively might pose a greater risk to retirement security than staying conservative – with the possible risk of not achieving enough capital growth.

However, the survey also found 84 per cent of the Americans polled said they would stay in the stock market even if they were to experience short-term losses, provided their retirement investment products have guaranteed income. Seventy-six per cent said they would stay invested in stocks for the longer-term.

Prudential says there is an increased awareness of guaranteed retirement income products and a strong interest in them, according to its findings. Seventy-five per cent of investors think these products are appealing, while 82 per cent see them as a valuable addition to their portfolio. More than half, 52 per cent, say having a stable income in retirement is a leading concern.

"When investors take risk off the table by getting out of the stock market, they potentially increase the risk that they will not be able to generate the returns they need to achieve their retirement goals. This research demonstrates that the likes of annuities and related products are more likely to keep people invested in the stock market - with the potential for higher returns, protection from market declines and benefits to the economy overall," said Stephen Pelletier, the president of Prudential Annuities.

The results were based on the responses of 1,001 Americans aged 45 to 75 through an online survey conducted in 4 to 12 May 2011. The participants were heads of mass affluent households with investable assets of at least $100,000, or $50,000 if retired and with retirement savings of at least $100,000.