Global shares hit a one-month low on Tuesday as investors refrained from placing strong bets before a Fed meeting that could adjust expectations about how soon the U.S. The MSCI world equity index, which tracks shares in 45 countries, was down 0.2 percent by 1047 GMT after hitting its lowest since mid-August earlier in the day in Europe. Speculation that the Federal Reserve could raise interest rates sooner and faster than previously predicted has rattled share markets around the globe and supported the U.S.