Abstract
OBJECTIVE: To examine whether the availability of primary medical care on-site at addiction treatment programs or off-site by referral improves patients’ addiction severity and medical outcomes, compared to programs that offer no primary care.
DESIGN: Secondary analysis of a prospective cohort study of patients admitted to a purposive national sample of substance abuse treatment programs.
SETTING: Substance abuse treatment programs in major U.S. metropolitan areas eligible for demonstration grant funding from the federal Substance Abuse and Mental Health Services Administration.
RESPONDENTS: Administrators at 52 substance abuse treatment programs, and 2,878 of their patients who completed treatment intake, discharge, and follow-up interviews.
MEASUREMENTS: Program administrators reported whether the program had primary medical care available on-site, only off-site, or not at all. Patients responded to multiple questions regarding their addiction and medical status in intake and 12-month follow-up interviews. These items were combined into multi-item composite scores of addiction and medical severity. The addiction severity score includes items measuring alcohol and drug use, employment, illegal activities, legal supervision, family and other social support, housing, physical conditions, and psychiatric status. The medical severity score includes measures of perceived health, functional limitations, and comorbid physical conditions.
MAIN RESULTS: After controlling for treatment modality, geographic region, and multiple patient-level characteristics, patients who attended programs with on-site primary medical care experienced significantly less addiction severity at 12-month follow-up (regression coefficient, −25.9; 95% confidence interval [95% CI], −43.2 to −8.5), compared with patients who attended programs with no primary medical care. However, on-site care did not significantly influence medical severity at follow-up (coefficient, −0.28; 95% CI, −0.69 to 0.14). Referral to off-site primary care exerted no detectable effects on either addiction severity (coefficient, −9.0; 95% CI, −26.5 to 8.5) or medical severity (coefficient, −0.03; 95% CI, −0.37 to 0.44).
CONCLUSIONS: On-site primary medical care improves substance abuse treatment patients’ addiction-related outcomes, but not necessarily their health-related outcomes. Further study is needed to discern the mechanism through which on-site primary care might improve the addiction-related outcomes of substance abuse treatment.
Similar content being viewed by others
References
Gerstein DR, Datta AR, Ingels JS, et al. National Treatment Improvement Evaluation Study. Final Report. Rockville, Md: Center for Substance Abuse Treatment, Substance Abuse and Mental Health Services Administration; 1997.
Friedmann PD, Lemon S, Anderson BJ, Stein MD. Predictors of follow-up health status in the Drug Abuse Treatment Outcome Study (DATOS). Drug Alcohol Depend. In press.
Stein MD. Medical consequences of substance abuse. Psychiatr Clin N America. 1999;22:351–70.
Simpson DD, Sells SB. Effectiveness of treatment of drug abuse: an overview of the DARP research program. Adv Alcohol Subst Abuse. 1982;2:7–29.
Hubbard RL, Marsden ME, Rachal JV, Harwood HJ, Cavanaugh ER, Ginzburg HM. Drug Abuse Treatment: A National Study of Effectiveness. Chapel Hill: The University of North Carolina Press; 1989.
Laine C, Hauck WW, Gourevitch MN, Rothman J, Cohen A, Turner BJ. Regular outpatient medical and drug abuse care and subsequent hospitalization of persons who use illicit drugs. JAMA. 2001;285:2355–62.
Levin SM, Trumble JG, Edmunds M, Statman JM, Peterson RC. Perspectives on linkage of primary health care and substance abuse treatment. J Addict Dis. 1993;12:1–8.
D’Aunno TA. Linking substance abuse treatment and primary health care. In: Egertson JA, Fox DM, Leshner AI, eds. Treating Drug Abusers Effectively. Malden, Mass: Blackwell Publishers; 1997:311–51.
Samet JH, Friedmann P, Saitz R. Benefits of linking primary medical care and substance abuse services: patient, provider, and societal perspectives. Arch Intern Med. 2001;161:85–91.
Umbricht-Schneiter A, Ginn DH, Pabst KM, Bigelow GE. Providing medical care to methadone clinic patients: referral vs on-site care. Am J Public Health. 1994;84:207–10.
Friedmann PD, Alexander JA, Jin L, D’Aunno TA. On-site primary care and mental health services in outpatient drug abuse treatment units. J Behav Health Serv Res. 1999;26:80–94.
Gerstein DR, Harwood HJ. eds. Treatment of Drug Problems: A Study of the Evolution, Effectiveness and Financing of Public and Private Drug Treatment Systems. Report of the Committee for the Substance Abuse Coverage Study, Division of Health Care Services, Institute of Medicine. Washington D.C.: National Academy Press; 1990.
McLellan AT, Kushner H, Metzger D, et al. The fifth edition of the Addiction Severity Index. J Subst Abuse Treat. 1992;9:199–213.
Nunally JC. Psychometric theory. 2nd ed. New York: McGraw Hill; 1978.
Susmilch CE, Johnson WT. Factor scores for constructing linear composites. Do different techniques make a difference? Sociol Meth Res. 1975;4:166–88.
Bryk A, Raudenbush S. Hierarchical Linear Models. Newbury Park: Sage; 1992.
Littell RC, Milliken GA, Stroup W, Wolfinger RD. SAS System For Mixed Models. Cary, NC: SAS Institute, Inc.; 1996.
Weisner C, Mertens J, Parthasarathy S, Moore C, Lu Y. Integrating primary medical care with addiction treatment: a randomized controlled trial. JAMA. 2001;286:1715–23.
Walsh DC, Hingson RW, Merrigan DM, Levenson SM, Coffman GA, Heeren T. The impact of a physician’s warning on recovery after alcoholism treatment. JAMA. 1992;267:663–7.
McLellan AT, Arndt IO, Metzger DS, Woody GE, O’Brien CP. The effects of psychosocial services in substance abuse treatment. JAMA. 1993;269:1953–9.
Broome KM, Simpson DD, Joe GW. Patient and program attributes related to treatment process indicators in DATOS. Drug Alcohol Depend. 1999;57:127–35.
Author information
Authors and Affiliations
Corresponding author
Additional information
This research was supported by National Institute on Drug Abuse (NIDA) grants K08 DA00320 and R01 DA13615. Dr. Friedmann is a Robert Wood Johnson Foundation Generalist Physician Faculty Scholar. The National Opinion Research Center of the University of Chicago in collaboration with the Research Triangle Institute collected the NTIES data under Contract No. ADM 270-92-0002 from Substance Abuse and Mental Health Services Administration/Center for Substance Abuse Treatment (SAMHSA/CSAT). The views expressed in this article are the authors’ and not necessarily those of the NIDA, SAMHSA/CSAT, or the Department of Health and Human Services.
Rights and permissions
About this article
Cite this article
Friedmann, P.D., Zhang, Z., Hendrickson, J. et al. Effect of primary medical care on addiction and medical severity in substance abuse treatment programs. J GEN INTERN MED 18, 1–8 (2003). https://doi.org/10.1046/j.1525-1497.2003.10601.x
Issue Date:
DOI: https://doi.org/10.1046/j.1525-1497.2003.10601.x