* Healthcare stocks drop after Clinton comments
* Gloomy earnings weigh on European shares
* Oil slumps after build in U.S. crude inventories (Updates to close of European markets)
By Sam Forgione
NEW YORK, Oct 21 (Reuters) - U.S. shares slipped on Wednesday on a tumble in healthcare stocks, while oil prices slumped after a build in U.S. crude inventories added to worries about oversupply.
Health insurers fell after Democratic presidential candidate Hillary Clinton said she has "serious concerns" about health insurer Aetna (N:AET) Inc's AET.N plan to acquire Humana Inc (N:HUM) HUM.N and Anthem Inc's ANTM.N proposal to buy Cigna Corp (N:CI) CI.N . The S&P healthcare index .SPXHC was last down 2 percent. urn:newsml:reuters.com:*:nL1N12L0XG
Valeant Pharmaceutical's VRX.N U.S.-listed shares lost a fourth of their value after short-seller Citron Research released a critical report on the company, while gains by General Motors (N:GM) GM.N and technology stocks capped losses in U.S. shares. urn:newsml:reuters.com:*:nL1N12L1OH
Gloomy quarterly reports dragged on European shares, but were offset by confidence over a positive close to the year and continued central bank support ahead of a European Central Bank meeting. urn:newsml:reuters.com:*:nL8N12L3XR
"During the course of the third quarter, we actually saw consensus estimates drop for both revenue and earnings," said Eric Weigand, senior portfolio manager at the Private Client Reserve at U.S. Bank.
"You could make the point that there is a low hurdle for companies to exceed on these diminished expectations."
Chinese bourses gave up earlier gains to close down 3 percent, the biggest fall since Sept. 15. urn:newsml:reuters.com:*:nZZN2RKR00
MSCI's all-country world equity index .MIWD00000PUS was last down 0.32 percent. Europe's broad FTSEurofirst 300 index .FTEU3 ended 0.02 percent lower at 1,431.61.
The Dow Jones industrial average .DJI was last up 0.15 percent, at 17,243.13. The S&P 500 .SPX was down 0.35 percent, at 2,023.69. The Nasdaq Composite .IXIC was down 0.72 percent, at 4,845.74.
Brent crude prices LCOc1 hit $47.50 a barrel, while U.S. crude CLc1 prices hit $44.86, their lowest levels since Oct. 2. The American Petroleum Institute on Tuesday reported a rise in U.S. commercial crude stocks of 7.1 million barrels to 473 million barrels in the week to Oct. 16, trumping expectations for an increase of 3.9 million barrels. urn:newsml:reuters.com:*:nL3N12L1GE
Rising supply from the largest-producing countries, along with slowing demand from emerging nations, has cut the price of oil in half over the last year.
"There is a surplus everywhere," Torbjorn Tornqvist, chief executive of Gunvor, told the Reuters Commodities Summit.
U.S. Treasury yields slumped after disappointing Japanese exports revived worries about sputtering world growth and dimmed prospects for a quick hike in U.S. interest rates. U.S. 30-year Treasury bonds US30YT=RR were last up 1-6/32 in price to yield 2.86 percent, from a yield of 2.92 percent late Tuesday.
The dollar rose against emerging-market and commodity-linked currencies as Chinese stocks slid, but dipped against the euro ahead of the ECB meeting. urn:newsml:reuters.com:*:nL1N12L15F
The dollar was last 0.56 percent higher against the Mexican peso MXN= at 16.65 pesos and was 0.8 percent higher against the Brazilian real at 3.94 reals BRL= . The euro was last up 0.08 percent against the greenback at $1.13540 EUR=EBS .
The dollar index, which measures the greenback against a basket of six major currencies, was last mostly flat at 94.926 .DXY .
Spot gold prices XAU= were last down $9.24, or 0.79 percent, at $1,166.46 an ounce.