<PAGE>   1
                                                                   EXHIBIT 10.52

                              THIRTEENTH AMENDMENT
                              TO CREDIT AGREEMENT
                                     AMONG
                           BEVERLY ENTERPRISES, INC.,
               BEVERLY HEALTH AND REHABILITATION SERVICES, INC.,
                    THE SUBSIDIARY GUARANTORS LISTED HEREIN,
                           THE LENDERS LISTED HEREIN,
                         BANK OF MONTREAL, AS CO-AGENT,
                                      AND
                    THE LONG-TERM CREDIT BANK OF JAPAN, LTD.
                          LOS ANGELES AGENCY, AS AGENT

                         Dated as of September 29, 1995



               THIS THIRTEENTH AMENDMENT dated as of September 29, 1995  (this
"Amendment"), is entered into by and among BEVERLY ENTERPRISES, INC., a
Delaware corporation ("BEI"), BEVERLY HEALTH AND REHABILITATION SERVICES, INC.
(formerly known as Beverly California Corporation), a California corporation
("Borrower"),  the  SUBSIDIARY  GUARANTORS  listed  on  the signature pages
hereof (together with BEI, the "Guarantors"), the LENDERS listed on the
signature pages hereof  (such lenders, together with each Person that may or
has become a party to the Credit Agreement (as defined below) pursuant to
subsection 10.8 thereof, are referred to herein individually as a "Lender" and
collectively as the "Lenders"), BANK OF MONTREAL as co-agent for the Lenders
(in such capacity, the "Co-Agent"), and THE LONG-TERM CREDIT BANK OF JAPAN,
LTD., Los Angeles Agency ("LTCB"), as agent for the Lenders (in such capacity,
the "Agent").  This Amendment amends the Credit Agreement dated March 24, 1992
by and among BEI, Borrower, Co- Agent, Agent and Lenders, as amended by that
First Amendment to Credit Agreement dated April 7, 1992 by and among BEI,
Borrower, Co-Agent, Agent and the Lenders, as further amended by that Second
Amendment to Credit Agreement dated as of May 11, 1992 by and among BEI,
Borrower, Co-Agent, Agent and the Lenders, as further amended by that Third
Amendment to Credit Agreement dated as of March 1, 1993 by and among BEI,
Borrower, Co-Agent, Agent and the Lenders, as further amended by that Fourth
Amendment to Credit Agreement dated as of November 1, 1993 by and among BEI,
Borrower, Co-Agent, Agent and the Lenders, as further amended by that Fifth
Amendment to Credit Agreement dated as of March 21, 1994 by and among BEI,
Borrower, Co-Agent, Agent and the Lenders, as further amended by that Sixth
Amendment to Credit Agreement dated as of April 22, 1994 by and among BEI,
Borrower, Co-Agent, Agent and the Lenders, as further amended by that Seventh
Amendment to Credit Agreement dated as of May 2, 1994 by and among BEI,
Borrower, Co-Agent, Agent and the Lenders, as further amended by that Eighth
Amendment to Credit Agreement dated as of





<PAGE>   2
November 1, 1994 by and among BEI, Borrower, Co-Agent, Agent and the Lenders,
as further amended by that Ninth Amendment to Credit Agreement dated as of
November 9, 1994 by and among BEI, Borrower, Co-Agent, Agent and the Lenders,
as further amended by that Tenth Amendment to Credit Agreement dated as of
December 6, 1994 by and among BEI, Borrower, Co-Agent, Agent and the Lenders,
as further amended by that Eleventh Amendment to Credit Agreement dated as of
March 27, 1995 by and among BEI, Borrower, Co-Agent, Agent and the Lenders, as
further amended by that Twelfth Amendment to Credit Agreement dated as of
October 23, 1995 by and among BEI, Borrower, Co- Agent, Agent and the Lenders
(said Credit Agreement, as so amended,  the  "Credit Agreement"),  as set
forth herein.  Capitalized terms used herein without definition shall have the
same meanings herein as set forth in the Credit Agreement.


                                    RECITALS


          WHEREAS,  Borrower desires to amend the Credit Agreement in certain
respects;

          WHEREAS, Lenders, Co-Agent and Agent have agreed to approve such
amendments;

          WHEREAS,  Guarantors  desire  to  reaffirm  the effectiveness
respectively  of  the  Subsidiary  Guaranty Agreement and the BEI Guaranty
Agreement;

          NOW, THEREFORE, in consideration of the terms and conditions herein
contained, BEI, Borrower, Guarantors, Co- Agent, Agent and Lenders agree as
follows:


                                  AGREEMENT


SECTION 1.        AMENDMENT TO SUBSECTION 1.1 OF THE CREDIT AGREEMENT

           Subsection 1.1 of the Credit Agreement is hereby amended by deleting
each of the definitions of "Adjusted Eurodollar Rate" and "Eurodollar Margin"
therefrom in their entirety and substituting the following therefor:

          "'Adjusted Eurodollar Rate' means for each Interest Period for any
     Eurodollar Rate Loan, (i) the rate per annum that appears on the display
     page designated as "LIBO Page" on the Reuter Monitor Money Rates Services
     (or such other page as may replace the "LIBO Page" on that service or any
     successor service) for U.S. dollar deposits  of  amounts  comparable  to
     the  outstanding principal amount of such Eurodollar Rate Loan and with






                                       2



<PAGE>   3
     maturities comparable to the Interest Period to be applicable to such
     Eurodollar Rate Loan, determined as of 11:00 A.M.  (London time)  on the
     date which is two Business Days prior to the first day of such Interest
     Period divided by (ii) a number equal to 1.00 minus the maximum rate or
     rates (expressed as a decimal fraction) of reserve requirements in effect
     on the day that is two Business Days prior to the beginning of such
     Interest Period   (including,   without   limitation,   basic,
     supplemental, marginal and emergency reserves under any regulations of the
     Board of Governors of the Federal Reserve System or other governmental
     authority having jurisdiction with respect thereto, as now and from time
     to time in effect) for Eurocurrency funding (currently referred to as
     'Eurocurrency liabilities' in Regulation D of such Board) that are
     required to be maintained by a member bank of such System (such rate to be
     rounded upward, if necessary, to the next higher 1/16 of 1%)."

            "'Eurodollar Margin' means, for any day, the rate per annum set
     forth under the column heading 'Eurodollar Margin' below for the ACD/CC
     Ratio and Cash Coverage Ratio in effect on such day or, if the ACD/CC
     Ratio and Cash Coverage Ratio in effect on such day do not coincide within
     one of the groupings below, the higher rate per annum set forth opposite
     the ACD/CC Ratio and Cash Coverage Ratio in effect on such day under the
     column heading 'Eurodollar Margin' below:

<TABLE>
<CAPTION>
                                                EURODOLLAR
          RATIO                                    MARGIN
<S>                                                <C>
ACD/CC Ratio less than 0.68; 
              and                                  0.750%               
Cash Coverage Ratio greater than or equal to
1.66

ACD/CC Ratio greater than or equal to 0.68 and
less than 0.72;
             and                                   0.875%
Cash Coverage Ratio greater than or equal to
1.56  and less than 1.66


ACD/CC Ratio greater than or equal to 0.68 and
less than 0.72;
             and
Cash Coverage Ratio greater than or equal to       1.125%
1.45 and less than 1.56
</TABLE>





                                       3

<PAGE>   4
<TABLE>
<S>                                                <C>
ACD/CC Ratio greater than or equal to 0.72 and
less than 0.74;
             and
Cash Coverage Ratio greater than or equal to       1.500%
1.40  and less than 1.45


ACD/CC Ratio greater than or equal to 0.74;
              or
Cash Coverage Ratio less than 1.40                 2.000%
</TABLE>


                 provided, however, that with respect to the period during
                 which the Eurodollar Margin is determined on the basis of a
                 Compliance Certificate delivered in respect of a fiscal
                 quarter ending during the period from and including September
                 30, 1995 through and including June 30, 1996, which period
                 shall in any event not extend beyond July 15, 1996 (the
                 'Relevant Period'), for any day during the Relevant Period,
                 'Eurodollar Margin' means the rate per annum set forth under
                 the column heading 'Eurodollar Margin' below for the ACD/CC
                 Ratio and Cash Coverage Ratio in effect on such day or, if the
                 ACD/CC Ratio and Cash Coverage Ratio in effect on such day do
                 not coincide within one of the groupings below, the higher
                 rate per annum set forth opposite the ACD/CC Ratio and Cash
                 Coverage Ratio in effect on such day under the column heading
                 'Eurodollar Margin' below:

<TABLE>
<CAPTION>
                                                   EURODOLLAR
                            RATIO                     MARGIN
<S>                                                   <C>
ACD/CC Ratio Less than 0.68;
        and                                           0.750%
Cash Coverage Ratio greater than or equal to
1.66

ACD/CC Ratio greater than or equal to 0.68 and
less than 0.72;
         and                                          0.875%
Cash Coverage Ratio greater than or equal to
1.56  and less than 1.66

ACD/CC Ratio greater than or equal to 0.68 and
less than 0.72;
         and
Cash Coverage Ratio greater than or equal to          1.000%
1.50  and less than 1.56
</TABLE>





                                         4
<PAGE>   5
<TABLE>
<S>                                                  <C>
ACD/CC Ratio greater than or equal to 0.68 and
less than 0.72;
          and
Cash Coverage Ratio greater than or equal to         1.125%
1.45  and less than 1.50

ACD/CC Ratio greater than or equal to 0.72 and
less than 0.74;
          and
Cash Coverage Ratio greater than or equal to         1.500%
1.40 and less than 1.45


ACD/CC Ratio greater than or equal to 0.74;
          or
Cash Coverage Ratio less than 1.40                   2.000%
</TABLE>


                      Any change in the Eurodollar Margin shall become
                 effective on the day on which Borrower has delivered a
                 Compliance Certificate pursuant to subsection 5.1D which
                 Compliance Certificate sets forth in reasonable detail the
                 Calculations required to establish a change in the ACD/CC
                 Ratio or Cash Coverage Ratio that requires a Change in the
                 Eurodollar Margin in accordance with this definition."

SECTION 2.     REPRESENTATIONS AND WARRANTIES

          In order to induce Agent, Co-Agent and Lenders to enter into this
Amendment, each of BEI and Borrower represents and warrants to Agent, Co-Agent
and Lenders that:

          (a)  The representations and warranties of each Loan Party contained
in the Credit Agreement are true, correct and complete in all material respects
on and as of the date hereof to the same extent as though made on and as of the
date hereof except to the extent that such representations and warranties
specifically relate to an earlier date, in which case they are true, correct
and complete in all material respects as of such earlier date;

          (b)  No event has occurred and is continuing or would result from the
execution of this Amendment that constitutes an Event of Default or Potential
Event of Default;

          (c)  Each Loan Party has performed in all material respects all
agreements and satisfied all conditions that the Credit Agreement and this
Amendment provide shall be performed by it on or before the date hereof;




                                         5




<PAGE>   6
         (d)  The execution, delivery and performance of this Amendment and
the Credit Agreement as amended by this Amendment, by each Loan Party are
within the corporate power and authority of each such Loan Party and,  as of
the Thirteenth Amendment Effective Date (as hereinafter defined), will be duly
authorized by all necessary corporate action on the part of each Loan Party,
and this Amendment, as of the Thirteenth Amendment Effective Date, is duly
executed and delivered by each of such Loan Parties and will constitute a valid
and binding agreement of each of such Loan Parties, enforceable against such
Loan Parties in accordance with its terms, except as may be limited by
bankruptcy, insolvency, reorganization,  moratorium or similar laws or
equitable principles relating to or limiting creditors' rights generally or by
equitable principles relating to enforceability.  The Credit Agreement
constitutes and,  as of the Thirteenth Amendment Effective Date, the Credit
Agreement, as amended by this Amendment, will Constitute, a valid and binding
agreement of BEI and Borrower, enforceable against BEI and Borrower in
accordance with its terms,  except as may be limited by bankruptcy, insolvency,
reorganization, moratorium or similar laws  or equitable  principles,  relating
to  or  limiting creditors'  rights generally or  by equitable  principles
relating to enforceability;

         (e)  The execution and delivery by each Loan Party of this Amendment
and the performance by each Loan Party of the Credit Agreement as amended by
this Amendment, do not and will not  (i)  violate any provision of any law or
any governmental rule or regulation applicable to any Loan Party, the
Certificate or Articles of Incorporation or Bylaws of any Loan Party or any
order, judgment or decree of any court or other agency of government binding on
any Loan Party, (ii) conflict with, result in a breach of or constitute (with
due notice or  lapse of time or both)  a default under any instrument that is
material, individually or in the aggregate, and that is binding on such Loan
Party, (iii) result in or require the creation or imposition of any Lien upon
any of the properties or assets of any Loan Party (other than any Liens created
under any of the Loan Documents in favor of Agent on behalf of Lenders), or
(iv) require any approval or consent of any Person under any instrument that is
material, individually or in the aggregate, and that is binding on such Loan
Party; and

         (f)  The execution and delivery by each Loan Party of this Amendment
and the performance by each Loan Party of the Credit Agreement as amended by
this Amendment, do not and will not require any registration with, consent or
approval of, or notice to, or other action to, with or by, any federal, state
or other governmental authority or regulatory body.






                                       6
<PAGE>   7
SECTION 3.     CONDITIONS TO EFFECTIVENESS

               Section 1 of this Amendment shall become effective only upon 
the satisfaction of all of the following conditions precedent (the date of
satisfaction of such conditions being referred to herein as the "Thirteenth
Amendment Effective Date"):

               A.   On or before the Thirteenth Amendment Effective Date,  BEI,
Borrower and each Subsidiary Guarantor shall deliver to Lenders (or to Agent
for Lenders with sufficient originally executed copies, as appropriate, for
each Lender and its counsel) the following, each, unless otherwise noted, dated
the Thirteenth Amendment Effective Date:

                    (i)  Signature and incumbency certificates of its officers 
        executing this Amendment certified by its secretary or an assist ant 
        secretary; and

                    (ii) Executed counterparts of this Amendment.

               B.   On or before the Thirteenth Amendment Effective Date, all 
Lenders shall have delivered to Agent a counterpart of this Amendment
originally executed by a duly authorized officer of such Lender or by telex or
telephonic confirmation.

SECTION 4.     THE GUARANTIES

               Each Guarantor acknowledges that it has reviewed the terms and 
provisions of the Credit Agreement and this Amendment and consents to the
amendment of the Credit Agreement effected pursuant to this Amendment. Each
Guarantor hereby confirms that the Guaranty Agreement and the Collateral
Documents to which it is a party or otherwise bound and all Collateral
encumbered thereby will continue to guaranty or secure, as the case may be, to
the fullest extent possible the payment  and  performance  of  all 
Obligations, Guarantied Obligations (as defined in the applicable Guaranty
Agreements) and  Secured  Obligations  (as  defined  in  the Collateral
Documents), as the case may be, including, without limitation, the payment and
performance of all Obligations of Borrower now or hereafter existing under or
in respect of the Credit Agreement as amended by this Amendment and the Notes
defined therein.

               Each Guarantor acknowledges and agrees that any of the Guaranty 
Agreements and the Collateral Documents to which it is a party or otherwise
bound shall continue in full force and effect and that all of its obligations
thereunder shall be valid and enforceable and shall not be impaired or limited
by the execution or effectiveness of this Amendment.   Each Guarantor
represents and warrants that all representations and warranties contained in
the Credit Agreement as amended by





                                         7


<PAGE>   8

this Amendment and the Guaranty Agreements and the Collateral Documents to
which it is a party or otherwise bound are true, correct and complete in all
material respects on and as of the Thirteenth Amendment Effective Date to the
same extent as though made on and as of that date except to the extent that
such representations and warranties specifically relate to an earlier date,  in
which case they are true,  correct and complete in all material respects as of
such earlier date.

               Each Guarantor acknowledges and agrees that (i) notwithstanding
the conditions to effectiveness set forth in this Amendment, such Guarantor is
not required by the terms of the Credit Agreement or any other Loan Document to
consent to the amendments to the Credit Agreement effected pursuant to this
Amendment or any other Loan Document and (ii) that neither the terms of the
Credit Agreement, any other Loan Document nor this Amendment shall be deemed to
require the consent of any Guarantor to any future amendments to the Credit
Agreement.


SECTION 5.     COUNTERPARTS; EFFECTIVENESS

               This Amendment may be executed in any number of counterparts, 
and by different parties hereto in separate Counterparts, each of which when so
executed and delivered shall be deemed an original,  but all such counterparts
together shall constitute but one and the same instrument.  This Amendment
(other than the provisions of Section 1 hereof) shall become effective upon the
execution of a counterpart hereof by all Lenders and each of the Loan Parties
and receipt of written or telephonic notification of such execution and
authorization of delivery thereof.

SECTION 6.     FEES AND EXPENSES

               Borrower acknowledges that all costs,  fees and expenses as 
described in subsection 10.4 of the Credit Agreement incurred by Agent and its
counsel with respect to this Amendment and the documents and transactions
contemplated hereby shall be for the account of Borrower.


SECTION 7.     EFFECT OF AMENDMENT

               It is hereby agreed that, except as specifically provided 
herein, this Amendment does not in any way affect or impair the terms and
conditions of the Credit Agreement, and all terms and conditions of the Credit
Agreement are to remain in full force and effect unless otherwise specifically
amended or changed pursuant to the terms and conditions of this Amendment.

                                        8


<PAGE>   9
SECTION 8.     APPLICABLE LAW

               This Amendment and the rights and obligations of the parties 
hereto and all other aspects hereof shall be deemed to be made under, shall be
governed by, and shall be construed and enforced in accordance with, the laws
of the State of New York without regard to principles of conflicts of laws.

                                        9




<PAGE>   10
          WITNESS the due execution hereof by the respective duly authorized 
officers of the undersigned as of the date first written above.


                                        BEI:
                                        
                                        BEVERLY ENTERPRISES, INC.
                                        
                                        
                                        
                                        By:
                                        Title   Sr. Vice President
                                        
                                        
                                        
                                        Borrower:


                                        BEVERLY  HEALTH  AND  REHABILITATION
                                        SERVICES,  INC.  (formerly known as
                                        Beverly California Corporation)
                                        
                                        
                                        
                                        By: 
                                            ----------------------------------
                                        Title:
                                        
                                        
                                        Agent, Co-Agent and Lenders.
                                        
                                        THE LONG-TERM CREDIT BANK OF JAPAN,
                                        LOS ANGELES AGENCY,
                                        as Agent and as a Lender
                                        


                                        By: 
                                            ----------------------------------
                                        Title:  
                                               -------------------------------


                                        BANK OF MONTREAL,
                                        as Co-Agent and as a Lender
                                        
                                        By:
                                        Title: 
                                               -------------------------------




                                   S-1


<PAGE>   11
                                        Lenders:
                                        
                                        INTERNATIONALE NEDERLANDEN (U.S.)
                                        CAPITAL CORPORATION
                                        
                                        
                                        
                                        By: 
                                            ----------------------------------
                                        Title: 
                                               -------------------------------
                                        
                                        
                                        U.S. NATIONAL BANK OF OREGON
                                        
                                        
                                        
                                        
                                        
                                        By: 
                                            ----------------------------------
                                        Title:      Jonathan A. Horton
                                                    Vice President





              The Subsidiary Guarantors:


                   Beverly Enterprises - Alabama, Inc.

                   Beverly Enterprises - Arkansas, Inc.

                   Beverly Enterprises - Florida, Inc.

                   Beverly Enterprises - Georgia, Inc.

                   Beverly Enterprises - Maryland, Inc.

                   Beverly Enterprises - Massachusetts, Inc.

                   Beverly Enterprises - Minnesota, Inc.

                   Beverly Enterprises - Mississippi, Inc.

                   Beverly Enterprises - Missouri, Inc.

                   Beverly Enterprises - Nebraska, Inc.

                   Beverly Enterprises - North Carolina, Inc.

                   Beverly Enterprises - Oregon

                   Beverly Enterprises - Wisconsin, Inc.




                                      S-2





<PAGE>   12
   Commercial Management, Inc.

   Hallmark Convalescent Homes, Inc.

   Hospital Facilities Corporation

   Moderncare of Lumberton, Inc.

   Nebraska City S-C-H, Inc.

   South Dakota - Beverly Enterprises, Inc.

   Vantage Healthcare Corporation

   AGI-Camelot, Inc.

   AGI-McDonald County Health Care, Inc.

   Beverly Enterprises - Arizona, Inc.

   Beverly Enterprises - California, Inc.

   Beverly Enterprises - Colorado, Inc.

   Beverly Enterprises - Connecticut, Inc.

   Beverly Enterprises - Garden Terrace, Inc.

   Beverly Enterprises - Hawaii, Inc.

   Beverly Enterprises - Idaho, Inc.

   Beverly Enterprises - Illinois, Inc.

   Beverly Enterprises - Indiana, Inc.

   Beverly Enterprises - Kansas, Inc.

   Beverly Enterprises - Kentucky, Inc.

   Beverly Enterprises - Louisiana, Inc.

   Beverly Enterprises - Michigan, Inc.

   Beverly Enterprises - New Jersey, Inc.

   Beverly Enterprises - Ohio, Inc.

   Beverly Enterprises - Pennsylvania, Inc.

   Beverly Enterprises - South Carolina, Inc.

   Beverly Enterprises - Tennessee, Inc.




                                     S-3



<PAGE>   13
         Beverly Enterprises - Texas, Inc.

         Beverly Enterprises - Utah, Inc.

         Beverly Enterprises - Virginia, Inc.

         Beverly Enterprises - Washington, Inc.

         Beverly Enterprises - West Virginia, Inc.

         Beverly Indemnity, Ltd.

         Beverly Manor Inc. of Hawaii

         Beverly Savana Cay Manor, Inc.

         Columbia-Valley Nursing Home, Inc.

         Computran Systems, Inc.

         Continental Care Centers of Council
           Bluffs, Inc.

         Forest City Building Ltd.

         Home Medical Systems,Inc.

         Kenwood View Nursing Home, Inc.

         Liberty Nursing Homes, Incorporated

         Medical Arts Health Facility of
           Lawrenceville, Inc.

         Nursing Home Operators, Inc.

         Petersen Health Care, Inc.

         Pharmacy Corporation of America

         Salem No. 1, Inc.

         South Alabama Nursing Home, Inc.

         American Transitional Care Centers of
           Texas, Inc.

         American Transitional Care Dallas-Ft.
           Worth, Inc.

         American Transitional Health Care, Inc.

         American Transitional Hospitals, Inc.





                                     S-4



<PAGE>   14
         American Transitional Hospitals of
           Indiana, Inc.

         American Transitional Hospitals of
           Oklahoma, Inc.

         American Transitional Hospitals of
           Tennessee, Inc.

         ATH Del Oro, Inc.

         ATH Heights, Inc.

         ATH Tuscon, Inc.

         Beverly Enterprises Japan Limited

         AdviNet, Inc.

         Beverly Crest Corporation

         Beverly Enterprises-Distribution Services,
           Inc.

         Hospice Preferred Choice, Inc.

         Beverly Rehabilitation Services, Inc.

         Synergos, Inc.

         Synergos-Scottsdale, Inc .

         Synergos-Pleasanthill, Inc.

         Synergos-North Hollywood, Inc.

                                  By:

                                  Title:  



                                     S-5