<PAGE>   1
                  UNITED STATES SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D.C. 20549
                               ------------------
                                 AMENDMENT NO. 1
                                       TO
                                   FORM 10-K/A

(Mark One)        [X]      Annual report pursuant to Section 13 or 15(d) of the
                           Securities Exchange Act of 1934 for the fiscal year
                           ended December 31, 1998

                  [ ]      Transition report pursuant to Section 13 or 15(d) of
                           the Securities Exchange Act of 1934 For the
                           transition period from ____________to________________

                         Commission File Number 0-21209
                           ADVANCED HEALTH CORPORATION
             (EXACT NAME OF REGISTRANT AS SPECIFIED IN ITS CHARTER)

Delaware                                            13-3893841
(STATE OR OTHER JURISDICTION                        (IRS EMPLOYER IDENTIFICATION
OF INCORPORATION OR ORGANIZATION)                   NUMBER)

555 White Plains Road, Tarrytown, New York          10591
(ADDRESS OF PRINCIPAL EXECUTIVE OFFICES)            (ZIP CODE)

                                 (914) 524-4200
              (REGISTRANTS' TELEPHONE NUMBER, INCLUDING AREA CODE)

        Securities registered pursuant to Section 12(b) of the Act: None

Securities registered pursuant to Section 12(g) of the Act: Common Stock, $.01
par value

         INDICATE BY CHECK MARK WHETHER THE REGISTRANT: (1) HAS FILED ALL
REPORTS REQUIRED TO BE FILED BY SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE
ACT OF 1934 DURING THE PRECEDING 12 MONTHS (OR FOR SUCH SHORTER PERIOD THAT THE
REGISTRANT WAS REQUIRED TO FILE SUCH REPORTS), AND (2) HAS BEEN SUBJECT TO SUCH
FILING REQUIREMENTS FOR THE PAST 90 DAYS.
YES [X] NO [ ]

         INDICATE BY CHECK MARK IF DISCLOSURE OF DELINQUENT FILERS PURSUANT TO
ITEM 405 OF REGULATION S-K IS NOT CONTAINED HEREIN, AND WILL NOT BE CONTAINED,
TO THE BEST OF REGISTRANT'S KNOWLEDGE, IN DEFINITIVE PROXY OR INFORMATION
STATEMENTS INCORPORATED BY REFERENCE IN PART III OF THIS FORM 10-K OR ANY
AMENDMENT TO THIS FORM 10-K: [X]

         THE AGGREGATE MARKET VALUE OF THE SHARES OF COMMON STOCK HELD BY
NON-AFFILIATES OF THE REGISTRANT IS $42,644,126, BASED ON THE CLOSING PRICE OF
THE COMMON STOCK ON MARCH 12, 1999. AS OF MARCH 12, 1999, THERE WERE 10,431,129
SHARES OF COMMON STOCK OUTSTANDING.

                       DOCUMENTS INCORPORATED BY REFERENCE

                                      None

                  STATEMENTS MADE OR INCORPORATED INTO THIS ANNUAL REPORT
INCLUDE A NUMBER OF FORWARD-LOOKING STATEMENTS WITHIN THE MEANING OF SECTION 27A
OF THE SECURITIES ACT OF 1933, AS AMENDED, AND SECTION 21E OF THE SECURITIES
EXCHANGE ACT OF 1934. FORWARD-LOOKING STATEMENTS INCLUDE, WITHOUT LIMITATION,
STATEMENTS CONTAINING THE WORDS "ANTICIPATES," "BELIEVES," "EXPECTS," "INTENDS,"
"FUTURE" AND WORDS OF SIMILAR IMPORT WHICH EXPRESS MANAGEMENT'S BELIEF,
EXPECTATIONS OR INTENT REGARDING THE COMPANY'S FUTURE PERFORMANCE. THE COMPANY'S
ACTUAL RESULTS COULD DIFFER MATERIALLY FROM THOSE SET FORTH IN THE
<PAGE>   2
FORWARD-LOOKING STATEMENTS. FORWARD-LOOKING STATEMENTS, INCLUDING STATEMENTS AS
TO INDUSTRY TRENDS, FUTURE ECONOMIC PERFORMANCE, ANTICIPATED PROFITABILITY,
ANTICIPATED REVENUES AND EXPENSES, AND PRODUCTS OR SERVICE LINE GROWTH MAY BE
SIGNIFICANTLY IMPACTED BY CERTAIN RISKS AND UNCERTAINTIES, INCLUDING, BUT NOT
LIMITED TO, FAILURE OF THE CLINICAL E-COMMERCE INDUSTRY TO DEVELOP AT
ANTICIPATED RATES, FAILURE OF THE COMPANY'S CLINICAL INFORMATION TECHNOLOGY
PRODUCTS AND SERVICES TO GAIN SIGNIFICANT MARKET ACCEPTANCE, FAILURE TO MEET
OPERATING OBJECTIVES OR TO EXECUTE THE OPERATING PLAN, FAILURE TO SUCCESSFULLY
RESTRUCTURE AHT'S BUSINESS UNITS, COMPETITION AND OTHER ECONOMIC FACTORS. NO
ASSURANCES CAN BE GIVEN AS TO THE OUTCOME OF ANY PENDING LAWSUITS AGAINST
ADVANCED HEALTH CORPORATION.

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ITEM 10. EXECUTIVE COMPENSATION

The following table sets forth a summary of the compensation of the Company's
Chief Executive Officer and each other executive officer of the Company who
earned in excess of $100,000 in annual salary and bonus during the Company's
fiscal year ended December 31, 1998 (collectively, the "Named Executive
Officers"), for services rendered in all capacities to the Company during the
Company's fiscal years ended December 31,1998, 1997, and 1996.

                           SUMMARY COMPENSATION TABLE

                             Long-Term Compensation
                           Annual Compensation Awards

<TABLE>
<CAPTION>
                                                                       Securities Underlying
                                                                       Options/SARs
Name and Principal Position                          Year              ($)Salary                 (#)
--------------------------------------------------------------------------------------------------------
<S>                                                  <C>               <C>                       <C>
Jonathan Edelson, M.D, Chairman,                     1998              298,589
Chief Executive Officer, and President               1997              269,079                   150,000
                                                     1996              220,224
Robert J. Alger, Executive Vice President            1998              178,431                   25,000
and Chief Information Officer                        1997              169,261                   60,000
                                                     1996              154,854
Jeffrey M. Sauerhoff                                 1998              172,902                   50,731
Chief Financial Officer                              1997              130,319                   22,255
                                                     1996              112,671
Eddy W. Friedfeld, Senior Vice President-            1998              152,566                   55,000
Business & Legal Affairs, General Counsel            1997              52,333                    22,500
and Secretary

Alan B. Masarek, President and COO (1)               1998              238,576
                                                     1997              224,693                   112,500
                                                     1996              200,198
</TABLE>

(1) Resigned Effective 3/31/99

<PAGE>   4
ITEM 11. SECURITY OWNERSHIP OF CERTAIN BENEFICIAL OWNERS AND MANAGEMENT


         The following table sets forth certain information regarding the
ownership of Common Stock as of May 1, 1999 with respect to (i) each person
known by the Company to own beneficially more than 5% of the outstanding shares
of Common Stock, (ii) each of the Company's directors, (iii) certain executive
officers of the Company and (iv) all directors and officers as a group. Unless
otherwise indicated, the address for each stockholder is c/o the Company, 555
White Plains Road, Tarrytown, New York 10591.


<TABLE>
<CAPTION>
                                                                      SHARES OF
                                                                      COMMON
NAME AND ADDRESS                                                      STOCK(1)               PERCENT(1)
-------------------------------------------------------------------------------------------------------
<S>                                                                  <C>                       <C>
David M. Knott
  485 Underhill Blvd., Suite 205, Syosset, NY 11791-3419              859,500                   8.1
Nationsbank Corp.
  Nationsbank Plaza, Charlotte, NC 28255                              785,600                   7.4
Dimensional Fund Advisors
  1299 Ocean Avenue, 11th Floor, Santa Monica, CA 90401               702,900                   6.6
Tudor Investment Corporation
  One Post Office Square, Boston, MA 02109                            723,000                   6.8
Jonathan Edelson, MD (2)                                              524,042                   4.9
Robert J. Alger (3)                                                    51,241                   *
Jeffrey M. Sauerhoff (4)                                               26,178                   *
Eddy W. Friedfeld (5)                                                   8,750                   *
James Carney (6)                                                       15,000                   *
Barry Kurokawa (7)                                                     19,507                   *
Alan B. Masarek (8)                                                   150,136                   1.4
Arthur M. Southam, MD                                                      *                    *

All directors and executive officers as a group (7 persons) (9)       794,854                   7.5
</TABLE>

* Represents less than 1% of the outstanding shares of Common Stock.

(1) Beneficial ownership is determined in accordance with the rules of the
Securities and Exchange Commission (the "Commission") and generally includes
voting or investment power with respect to securities and includes options
exercisable within 60 days of May 1, 1999. Except as indicated by footnote, and
subject to community property laws where applicable, the persons named in the
table above have sole voting and investment power with respect to all shares of
Common Stock shown as beneficially owned by them. Percentage of beneficial
ownership is based on 10,644,244 shares of Common Stock outstanding as of May 1,
1999.

(2) Includes currently exercisable options to purchase 128,816 shares of Common
Stock.

(3) Includes currently exercisable options to purchase 51,241 shares of Common
Stock.

(4) Includes currently exercisable options to purchase 26,178 shares of Common
Stock.

(5) Includes currently exercisable options to purchase 8,750 shares of Common
Stock.

(6) Includes currently exercisable options to purchase 15,000 shares of Common
Stock.

(7) Includes currently exercisable options to purchase 17,507 shares of Common
Stock.

(8) Includes currently exercisable options to purchase 150,136 shares of Common
Stock

(9) See notes (2), (3), (4), (5), (6), and (7).


<PAGE>   5
ITEM 12. CERTAIN RELATIONSHIPS AND RELATED TRANSACTIONS

         In 1996, 1997 and 1998, in accordance with the Company's Senior
Executive Loan Policy, which is administered by the Compensation Committee of
the Board of Directors, the Company made loans in the aggregate amounts of
$800,000 and $145,000 to each of Dr. Edelson, and Mr. Alger, respectively. These
loans are due three years from the loan date with interest payable monthly at a
rate of 6% per annum.

         The Company entered into a separation agreement in 1999 with Alan
Masarek, the Company's former President and Chief Operating Officer, whose
resignation was effective March 31, 1999, which provides for the following: (i)
a one-year continuation of salary at $250,000 and benefits from April 1, 1999 to
March 31, 2000, payable monthly; (ii) an additional $250,000 (less applicable
withholding) payment in exchange for consulting forup to 24 business days in a
form and manner reasonably requested by the Company's Board of Directors, which
has already been paid; (iii) requirement of repayment of current outstanding
loans, principal ($467,475) and interest (at the rate of 6% per annum),
beginning May 1, 2000 at the rate of $15,000 per month with the balance due of
all outstanding loans, including principal and interest on May 1, 2001; (iv)
vesting of 150,136 options to acquire Company stock that will remain fully
exercisable for up to five years; and (v) a success bonus for the sale of the
management services division of the Company that occurred on May 14, 1999 ("the
Sale"), equal to $40,000 plus 2.5% of the net proceeds of the Sale, which has
already been paid.

         The Company believes that all of the transactions set forth above were
made on terms no less favorable to the Company than could have been obtained
from unaffiliated third parties. All transactions, including loans, between the
Company and its officers, directors and principal stockholders and their
affiliates are approved by a majority of the Board of Directors, including a
majority of the independent and disinterested outside directors of the Board of
Directors.


<PAGE>   6
                                   SIGNATURES


         Pursuant to the requirements of the Securities Exchange Act of 1934,
the Registrant has duly caused this report to be signed on its behalf by the
undersigned thereunto duly authorized.



                                    ADVANCED HEALTH  CORPORATION



Date: June 10, 1999
                                    By:  /s/ Jeffrey M. Sauerhoff

                                    Jeffrey M. Sauerhoff
                                    Chief Financial Officer


<PAGE>   7
                                  EXHIBIT INDEX

EXHIBIT NO.       DESCRIPTION OF EXHIBIT

**3.1             Restated Certificate of Incorporation of the Registrant

**3.2             By-laws of the Registrant

**10.7            Tarrytown, New York Office Lease Agreement dated November 30,
                  1995, between Tarrytown Corporate Center IV, L.P. and the
                  Registrant.

**10.8            First Amendment to Lease Agreement between Reckon Operating
                  Partnership, LP, as Owner, and the Registrant, as Tenant

**10.9            Chicago Office Lease Agreement dated December 8, 1995, between
                  Adams Family, LLC and the Registrant

**10.10           Fort Washington Lease Agreement dated November 13, 1997,
                  between Comdrive Associates, L.P. and Registrant as Tenant

**10.11           Hawthorne Lease Agreement dated January 8, 1998, between
                  United Parcel Service, Inc. and Registrant as Tenant

**10.12           Malvern Lease dated October 6, 1997

**10.13           Tarrytown Sublease

**10.14           Form of Director Indemnification Agreement

 *10.15           Employment Agreement between the Registrant and Jonathan
                  Edelson, M.D.

 *10.16           Employment Agreement between the Registrant and Robert Alger

**10.17           Employment Agreement between the Registrant and Jeffrey M.
                  Sauerhoff

**10.18           Employment Agreement between the Registrant and Eddy W.
                  Friedfeld

 *10.19           Separation Agreement between the Registrant and Alan B.
                  Masarek

**10.20           Amended and Restated Advanced Health Corporation 1995 Stock
                  Option Plan

**10.21           Employee Stock Purchase Plan

**11.1            Earnings Per Common Share Computation

**21              List of Subsidiaries

**23.2            Consent of Arthur Andersen LLP

**27              Financial Data Schedule

*                 Filed herewith.
<PAGE>   8

**       Filed as an exhibit to the Registrant's Registration Statement on Form
S-1, as amended Registration No. 333-06283), Registrant's Registration Statement
on Form S-1, as amended (Registration No. 333-35115), Registrant's Forms 10-K,
dated March 30, 1997, March 31, 1998, and April 2, 1999, incorporated herein by
reference.