ELSEVIER Drug and Alcohol Dependence 45 (1997) 105- 1 I?

Cost-effectiveness of treatment for drug-abusing pregnant women

Date S. Svikis ‘,*, Archie S. Golden a, George R. Huggins ‘, Roy W. Pickens b, Mary E. McCaul ‘, Martha L. Velez d, C. Todd Rosendale ‘, Robert IS. Brooner ‘I,

Preston M. Gazaway a, Maxine L. Stitzer ‘, Carol E. Ball d

’ The Johns Hopkins University School of Medicine, 4940 Eastern Avenue, Baltimore. MD 21224. C’S.4 ’ National Institute on Drug Abuse, Baltimore, MD 21224, USA

’ Maryland State Alcohol and Drug Abuse Administration. Baltimore, MD 21224, USA ’ The Johns Hopkins Bayview Medical Center, 4940 Eastern Avenue. Bultimore. MD 21224. L’SA

Received 31 July 1996; accepted 27 January 1997

Abstract

Neonatal intensive care unit (NICU) and drug treatment costs were compared in two groups of pregnant drug abusing women: 100 admissions to a multidisciplinary treatment program and active in care at the time of delivery and 46 controls not entering drug treatment. Clinical measures included urine toxicology at delivery, infant birthweight, Apgar scores and need for and duration of NICU services. Cost measures included drug treatment and NICU costs. Treatment patients showed better clinical outcome at delivery, with less drug use and higher infant estimated gestational age, birthweight and Apgar scores. Infants of treatment patients were also less likely to require NICU services and, for those that did. had a shorter stay. When total cost was examined (including drug treatment), mean net savings for treatment subjects was $4644 per mother/infant pair. The study demonstrates the cost-effectiveness of treatment for pregnant drug abusing women, with savings in NICU costs exceeding costs of drug treatment. 0 1997 Elsevier Science Ireland Ltd.

Keywords: Pregnancy; Drug dependence; Treatment; Cost-Effectiveness; Outcome

1. Introduction

An estimated 6-24% of women use illicit drugs dur- ing pregnancy (Glantz and Woods, 1993; Matera et al., 1993). While many casual users will respond positively to minimal intervention, others are drug dependent and require drug abuse treatment (Svikis and Huggins, 1996). Drug dependent women often present for treat- ment with a myriad of health and psychosocial prob- lems (Chasnoff, 1992; Jones and Lopez, 1990; Miller and Hyatt, 1992). Compared to women in the general population, they have higher rates of spontaneous abortion, placental abruption and premature labor (Robins and Mills, 1993). Their infants also have in-

* Corresponding author. Tel.: + 1 410 5503023; fax: + 1 410 5503027.

creased rates of medical problems chiefly related to prematurity, but also to Fetal Alcohol Syndrome (FAS), Sudden Infant Death Syndrome (SIDS) and neonatal drug abstinence syndrome (Miller and Hyatt, 1992; Robins and Mills, 1993).

Recently, attention has focused on the high cost of providing treatment for pregnant drug abusing women (Philbbs et al., 1991). Much of this cost is associated with stays of drug-exposed infants in neona- tal intensive care units (NICU). NICU cost in a general hospital setting, exclusive of physician fees, varies from $750-$1,750 per day, depending on nature and scope of services provided (Kandall, 1993). Infants of drug-using mothers are more likely to be admitted to and have longer duration of NICU stay than infants of non-drug-abusing women (Calhoun and Watson, 1991).

0376-8716/97/$17.00 0 1997 Elsevier Science Ireland Ltd. All rights reserved PIISO376-8716(97)01352-5

However, providing drug abuse treatment to drug- dependent women can also be expensive (Goodman et al.. 1992). Nationally, alcohol/drug treatment costs for inpatient care range from $4,000 to $15,000, with stan- dard outpatient care averaging $400 to $1,500 per treatment episode (Holder, 1987; Holder and Hallan, 1986: Miller and Hester, 1986). The median length of stay in drug treatment programs is 28.3 weeks for methadone maintenance. 11 .O weeks for residential/ therapeutic communities and 7.9 weeks for outpatient drug-free treatment (Hubbard et al., 1989). The medical problems associated with drug abuse during pregnancy, as well as the poor outcomes of such women in tradi- tional treatment settings, have suggested the need for comprehensive, multidisciplinary programs, which are more costly to operate and maintain than standard treatment programs (Horgan et al., 1991; Philbbs et al., 1991).

To date. the cost-effectiveness of providing treatment to drug-dependent women and their offspring has not been systematically studied (Horgan et al., 1991). To address this issue, we compared NICU hospitalization rates for infants of two groups of demographically similar patients. One group was pregnant drug abusing women who had enrolled in a multidisciplinary treat- ment program providing both prenatal medical and drug abuse treatment services and who were active in care at the time of delivery. The other group (control) was pregnant drug abusing women who delivered in the same hospital system prior to opening of the multidisci- plinary treatment program. They were identified as having drug abuse problems either during their initial obstetrical visits or at the time of labor/delivery; how- ever, none received drug abuse treatment during their pregnancy.

The clinical outcomes of infants from these two groups were examined with NICU cost estimated by length of stay abstracted from medical records. Previ- ous research has found that NICU costs are the most significant contributor to total costs for treatment of drug-exposed women and their infants (Calhoun and Watson, 1991). In addition, the cost of providing drug abuse treatment to women in the treatment group was included in the cost analysis. Not included in the analy- sis were prenatal and postnatal maternal care costs, as such care only accounts for a modest amount of total costs and in some studies does not correlate with im- provements in birth outcomes (Calhoun and Watson, 199 1; Fiscella, 1995). Also excluded were costs for pediatric or other medical or drug abuse treatment services following labor and delivery. It was expected that being enrolled in the multidisciplinary treatment program would result in improved infant outcome, which would translate into greater cost effectiveness than not being enrolled in treatment.

2. Materials and methods

2.1. Subj6wt.s

Only women reporting current medical or psychoso- cial problems resulting from inability to control drug use were included in the study. The treatment group (N= 100) was selected from the first 288 pregnant drug-abusing women voluntarily admitted to the Center for Addiction and Pregnancy (CAP). The program provides substance abuse, mental health, obstetrics and gynecology, family planning and pediatric services in a single hospital-based treatment site. Drug abuse treat- ment consisted of 1 week of residential care followed by intensive outpatient (day treatment) services through labor/delivery (Jansson et al., in press). All admissions occurred between April, 1991 and October, 1992. Ex- cluded were women who (1) had less than two prenatal visits or attended less than 2 weeks of treatment (N = 78); (2) had a stillbirth or multiple birth (N = 6); (3) had incomplete outcome data (N = 3) or (4) were not active in treatment at the time of delivery or delivered at another hospital (N = 101).

The control group (N = 46) was selected from 141 pregnant drug abusing women who did not receive drug abuse treatment. All were patients in a sister hospital serving the same catchment area in Baltimore City as the treatment program. Included were (1) women as- sessed as needing drug abuse treatment at the initial prenatal examination but refusing to follow through with referral to drug treatment (N= 34); and (2) women who sought neither prenatal nor drug treatment services during pregnancy and presented unregistered to labor and delivery (drug problem identified at time of delivery) (N = 12). Excluded were women without labor/delivery records who delivered elsewhere (N = 95). There were no multiple or stillbirth cases in the final sample. Control subjects delivered between April, 1989 and September, 1990 immediately prior to open- ing of the treatment program (April, 1991).

The two groups did not differ in race, marital status, type of insurance coverage, and parity (Table 1). How- ever, treatment subjects were approximately 3 years older and averaged 6 months more years of education than controls (P < 0.05). To control for group differ- ences, these measures were employed as covariates in subsequent data analyses.

2.2. Drug use

Perinatal drug use by both treatment and control subjects was evaluated by interventionists similarly trained by clinical psychologist co-investigators (DSS, RKB) using standard drug abuse assessment proce- dures. Assessment occurred on program admission for treatment subjects, or at the time of the first prenatal

D.S. Scikis et (11. /Drug and Alcohol Dependence 45 (1997) 105-- 113 107

Table 1 Demographic and substance use characteristics of subjects

Mean age (years)

Race African American Caucasian

Education (mean year)

Marital Status Single/never married

Insurance Federal medical assistance

Parity Mean full-term births Mean premature births Mean abortions Mean living children

EGA on admission (weeks)

Tobacco use Current, daily

Substance use problems Cocaine Heroin/opiates Alcohol Other

Intravenous drug use

Treatment (N = 100)

21.1

85% 15%

II.2

89%

1 00%

1.5 0.2 1.4 I.6

26.5

99%

77% 43% 16% I 8%

31%

Controls (.I’ = 46)

24.6

85% I5”~:,

IO.6

85’::)

I 00%

1.2 0.3 1.2 I.4

~~~ ‘1

‘3

61% 43% I I’%, 24%

37%

P-value

0.0002

N.S.

0.05

N.S.

N.S.

N.S. N.S. N.S. N.S.

0.05 N.S. N.S. N.S.

N.S.

’ Not available.

visit or following labor/delivery for control subjects. Assessment included quantity and frequency of recent drug use, typical route of drug administration and problems associated with drug use. All subjects (both treatment and controls) were actively using illicit drugs at the time of first contact, based either on self-report or urine toxicology results. Almost all treatment sub- jects reported current tobacco use; data on tobacco use was not available for control subjects. Drug use by both groups was similar, except treatment subjects were more likely than controls to have a cocaine problem (P < 0.05); this difference was also statistically con- trolled in data analyses. There were no differences between the groups in lifetime intravenous drug use.

In addition, Addiction Severity Index (ASI) (Third Edition) (McLellan et al., 1980) data were available on 61% of treatment and 44% of control subjects. AS1 assessment was related primarily to staff and patient availability and no subject refused assessment. Subjects with and without AS1 data did not differ in demo- graphics (age, race, education) or birth outcomes (EGA at delivery, infant birthweight) (P > 0.05). The AS1 is a widely used and well validated semi-structured inter- view for assessing lifetime regular alcohol or drug use (use any amount three times or more per week), heavy

alcohol use (used three or more drinks at least three times per week, etc.) and other domains of psychosocial functioning (medical, employment, legal, family/social, psychiatric) in drug abusing populations.

Treatment and control subjects were similar on most AS1 measures of drug use (Table 2). In all cases where group differences were found, treatment subjects had indications of a more severe substance use problem than control subjects. For example, treatment subjects had a younger age of onset of both alcohol (P < 0.03) and marijuana use (P < 0.02) and a longer period of lifetime cocaine use (P < 0.02). The two groups were also similar on 48 of 58 AS1 measures of psychosocial functioning. On nine of the ten measures with differ- ences, treatment subjects had scores that were indicative of more severe problems than control subjects. Only on the medical composite score did control subjects have a higher score than treatment subjects, with scores for both groups being in the low-severity range. Since the patient’s subjective assessment of need for additional medical services is primarily reflected by this scale, lower scores by treatment subjects would be expected due to the ready availability of medical services in the treatment program.

108 D.S. Sciki.s et ul. Drug and Al~hl Depmdence 45 (1997) IOS il.?

Table 2 Alcohol and drug use severity from addiction severity index

--- _--- .--~

Treatment (N = 61) Controls (,Y = 20) P-VdUC

Ilervin 4gc of onset (years) 21.8 23.2 N.S. Regular heroin use, lifetime (no. of months) 18.1 12.4 N.S.

Cocaine Age of onset (years) 21.2 23.2 N.S.

Regular cocaine use, lifetime (no. of months) 34.0 14.9 0.02

Alcohol Age of onset (years) 15.0 17.3 0.03

Regular alcohol use, lifetime (no. of months) 29.8 19.4 N.S.

Regular heavy alcohol use, lifetime (no. of months) 24.1 19.4 N.S.

Marijuana Age of onset (years) 15.2 17.1 0.02

Regular marijuana use, lifetime (no. of months) 26.2 16.4 N.S.

2.3. Cost computations

For both groups, all decisions about NICU admis- sion and length of stay were made by members of the NICU staff; staff of the treatment program and ob- stetrical/delivery services were not involved in these decisions. Protocols for NICU admissions were com- parable for the two sites. For both groups, maternal and infant clinical outcome measures were abstracted from hospital and/or drug abuse treatment records. NICU data (e.g. admission information, length of stay) were abstracted from medical records and/or nursing ledgers. NICU costs were estimated from length of stay of each infant on the unit. Costs were standardized by applying the same NICU daily service rate to each subject. Separate group estimates were calculated for the minimum ($750/day), maximum ($1750) and aver- age ($1200) daily service rates for NICU units that have been reported (Kandall, 1993).

Drug abuse treatment costs were obtained directly from billing records for subjects in the treatment pro- gram. Using rates approved by the State of Maryland Hospital Cost Setting Commission, patient costs were based upon the number of treatment hours attended each day. At the time the study was conducted, treat- ment rates for both residential and outpatient care averaged $179/day for full day attendance; $125/day for half day attendance; and $68 for shorter duration atten- dance (e.g. attending one group therapy session).

Total drug abuse treatment costs for each woman in the treatment program varied with frequency and inten- sity of program participation as well as estimated gesta- tional age (EGA) on admission. That is, women who entered treatment during the first or second trimester had a longer window of opportunity for treatment services than women who enrolled in treatment during the third trimester of pregnancy. Since control subjects

did not enter drug abuse treatment, their drug abuse treatment costs were zero.

2.4. Data analysis

The impact of treatment on continuous and categori- cal data was examined using Student’s t-tests and x2 analyses, respectively, with Fisher’s exact test employed when expected cell frequencies were less than 5. To control for differences in treatment and control subjects that existed at the time of hospital admission; analysis of covariance was employed using age, education, and cocaine use as covariates. Alpha level was 0.05 (two- tail).

3. Results

3.1. Clinical outcome

Mean number of prenatal visits was 8.4 for treatment and 4.0 for control subjects (5.6 for clinic registered controls). Control subjects were almost twice as likely to be using illicit drugs at the time of delivery as women in the treatment group (63.2 and 36.8%, respectively, for positive urine drug toxicology) (Table 3). In addi- tion, infants of treatment subjects had better clinical outcomes on a number of measures. Their infants had mean birthweights approximately 400 g higher and an estimated gestational age approximately 3 weeks longer than infants of control subjects. Incidence of low birth- weight ( < 2500 gm) was 2.6 times higher for infants of controls than treatment women, with 17% of control infants being classified as having very low birthweight ( < 1500 g) compared to none of the infants of treat- ment subjects. Infant Apgar scores at 1 and 5 min were also significantly higher for infants of treatment sub-

D.S. Svikis et al. /Drug und Alcohol Dependence 45 (1997) 105 113 109

Table 3 Maternal and infant clinical outcomes

Treatment (N= 100) Controls (N = 46) Adjusted P-value*

Maternal Positive drug screen at delivery

Neonate EGA (mean wk) Birthweight (mean gm) Low birthweight ( < 2500 g) Very low birthweight (< 1500 g) Apgar (mean 1 min) Apgar (mean 5 min) NICU hospitalization

Mean NICU length of stay NICU admissions only All infants

36.8% 63.2% 10.001

38.6 35.4 <O.OOl

2934 2539 <O.OOl 15% 39% <O.OOl 0% 17.4% <o.oot 1.1 6.8 0.004

8.8 8.5 0.004

lo”/11 26% 0.01

6.6 days 38.9 days 0.01 0.8 days 10.2 days 0.01

* Controlling for initial group differences in age, education, and cocaine use.

jects than controls, indicating improved perinatal func- tioning.

Infants of controls were more than twice as likely (26%) to require NICU hospitalization as infants of treatment subjects (10%). The mean length of NICU stay was also significantly different for the two groups. When only infants requiring NICU admission were considered, infants of controls had a mean NICU stay that was almost six times longer (38.9 days) than in- fants of treatment women (6.6 days). When all infants of treatment and control subjects were compared, the mean number of days spent on the NICU by infants of control subjects was almost 12 times longer (10.2 days) than infants of treatment subjects (0.8 days). While most infants in both groups did not require NICU stay (i.e. modal and median length of stay = 0 days for both groups), a larger proportion of controls than treatment subjects required longer NICU stays (Table 4). The mean length of stay for controls was significantly influ- enced by one infant (167 days). However, even when this infant was eliminated from the data analysis, a significant difference between length of NICU stay for infants of treatment and control groups remained (P < 0.004L

Table 4 Length of stay in NICU

No. of days

0 IL4 5--8 9-12 13-16 17+

Infants

Treatment (‘!l) 90 5 3 I I I

Controls (“/;I) I4 2 0 4 2 17

3.2. Cost-effectiveness outcome

Total NICU costs were proportional to the number of days spent in the NICU (Table 5). At an average cost of $1200/NICU day, the mean NICU cost for infants requiring a NICU stay was $7920/infant for treatment subjects compared to $46 700/infant for con- trol subjects. Across all infants, the mean NICU cost per treatment episode was $900/infant for the treatment group compared to $12 183/infant for the control group. Applying the minimum and maximum NICU daily service rates that have been reported (Kandall, 1993), NICU costs were proportionately lower and higher, respectively. Substance abuse treatment costs for subjects in the treatment program varied widely due to differences in EGA on admission and delivery, fre- quency of program attendance, and intensity of services provided (e.g. number of individual and group counsel- ing sessions attended per day). Actual costs ranged from $687 to $20 78llpatient with a mean patient cost of $6639.

Total treatment costs per mother/infant pair was determined by adding mean actual drug abuse treat- ment cost to mean estimated NICU infant cost. For the treatment group, total treatment cost was sig- nificantly less than that for controls (who had NICU infant cost only). The amount of the saving was pro- portional to the NICU daily service rate. At an average NICU service rate of $1200/day, a net cost savings of $4644 per mother/infant pair was as- sociated with being in drug abuse treatment. Cost sav- ings were greatest for the highest NICU daily service rates.

I IO D.S. Scikis et ul. Drug and Alwl~~l Dependencr 45 (1997) 105~-1 I.3

Table 5 Economic outcomes (standardized in dollars) based on length of NICU stay -___-. _________ ---___ _ -._.___ Savings* Treatment (N = 100) Controls (!\i = 46) Nrr

NICU Drug Abuse Total NICUTotal

Minimum NICU Cost ($750/day) 600 6639 7239 7650 411 Average NICU Cost ($1200/day) 900 6639 7539 12.183 4644 Maximum NICU Cost ($1750/day) 1400 6639 8039 17,850 9811

* All group differences significant at P<O.Ol controlling for initial group differences in age, education and cocaine use.

4. Discussion

These results suggest that substance abuse treatment during pregnancy has significant health benefits to preg- nant drug abusing women and produces considerable cost savings as well. Although the pregnant drug abus- ing subjects were not randomly assigned to treatment or control groups for ethical reasons, few differences were evident between the groups on first contact with the health system. Where group differences existed, AS1 data (available on approximately half of the subjects in each group) suggested that treatment subjects were more severely affected than controls. Nevertheless, treatment subjects showed more significant reductions in illicit drug use prior by delivery and their infants have significantly fewer medical problems than con- trols.

These results may be due to a number of factors. Since data were not available on women who dropped out of treatment prior to delivery, it is not clear if the findings represent a self-selection bias or a treatment effect. Neither is it clear if the findings are due to increased amount of medical services (e.g. prenatal visits) received by women in the treatment group or to the effects of drug abuse intervention.

Advocacy for specialized programs to meet the di- verse treatment needs of pregnant drug-abusing women has recently occurred at the federal, state, and local levels (Horgan et al., 1991; White House, 1989). Estab- lishing and maintaining such programs is expensive, however. In the present economic climate of shrinking health care dollars, it is important that cost-effective- ness of such models be evaluated. Recent reviews of treatment effectiveness by the National Institute on Drug Abuse (Apsler and Harding, 1991) and other research groups (Cross et al., 1988; Hubbard et al., 1989) have found cost-effectiveness studies of drug abuse treatment to be rare. The present study is one of the first to examine cost-effectiveness of treatment of pregnant drug abusing women, where the health impact is shared by their infants as well.

Treatment effectiveness was demonstrated by lower rates of urine positive drug toxicology in treatment subjects than controls at the time of labor/delivery. While a significant cost savings was associated with

being enrolled in treatment, the data are even more encouraging when it is recognized that many drug- abusing women come into contact with the treatment delivery system relatively late in their pregnancies (e.g. mean EGA on admission 26.5 weeks). Typically, women in the treatment program reported minimal or no prenatal care prior to enrollment. Thus, despite continued drug use during a substantial portion of their pregnancy, significantly better maternal and infant birth outcomes were still demonstrated compared to women who did not enter treatment. This occurred even though the treatment subjects had more severe substance use characteristics than controls. If strategies are developed to encourage more women to enroll in drug treatment earlier in their pregnancies, clinical out- comes (and savings) may be further enhanced. Long term infant prognosis is closely linked to the child’s receiving early assessment and intervention.

The costs for treating control subjects were similar to the costs reported for treating drug-exposed infants in another study. That study reported 30% of infants of cocaine-using mothers required NICU hospitalization (vs. 26% in the present study), a mean length of NICU stay of 11 days (vs. 10.2 days in the present study), and an average NICU cost of $13 222 per infant (vs. $12 183 in the present study) (Calhoun and Watson, 1991). The demonstrated cost savings of approximately $4644 per mother/infant pair is a conservative estimate based on an average NICU cost of $1200/day. Given the higher prevalence of serious complications (e.g. very low birth- weight infants) for infants of control subjects, the net savings for the women in the treatment group would be expected to be even greater if actual costs were used.

The cost-benefit analysis in this study was conserva- tive since it did not include several relevant but unmea- sured aspects of infant and maternal outcomes. For example, Philbbs et al. (1991) found that the costs of keeping cocaine-exposed infants in hospital nurseries while awaiting evaluation or foster care placement in- creased cost by more than $3500 per case. In addition to high rates of NICU hospitalization, infants of un- treated drug abusing women are likely to require inten- sive pediatric medical care following NICU discharge. Infants exposed to drugs in utero are known to have higher rates of learning disabilities, cognitive impair-

D.S. Saikis et al. /Drug and Alcohol Dependence 45 (1997) 105-l 13 111

ments and neurological problems (Finnegan and Kan- dall, 1992; Kolar et al., 1994; Robins and Mills, 1993; Zuckerman and Bresnahan, 1991). The impact of drug abuse treatment on such problems is at present un- known, but to the extent reducing prenatal drug use reduces such problems, treatment should have addi- tional cost-effectiveness. Long-term follow-up studies are needed to examine the impact of drug treatment on developmental outcomes for these high-risk infants (Bauman and Levine, 1986; Kandall, 1993).

In general, drug abusing women have higher rates of medical complications during pregnancy (Glantz and Woods, 1993; Imaizumi, 1992; Jones and Lopez, 1990; MacGregor et al., 1987; Robins and Mills, 1993), which translate into higher medical care costs. However, it should be noted that the impact of prenatal care costs on total costs of treatment are minimal compared to costs of care for low birthweight infants. For example, in the present study the mean number of prenatal visits was 8.4 for treatment and 4.0 for control subjects (5.6 for clinic registered controls). The costs of additional prenatal visits by treatment subjects do not contribute significantly to net costs. In addition, the additional cost of prenatal care would be expected to be offset by savings that will occur from reduced maternal medical procedures at labor/delivery and postpartum.

Other medical services provided in the treatment program are expected to yield additional unrecognized cost savings. For example, women in the comprehensive program had a mean of 1.7 other children. Thus, for many family planning was a desired treatment option. Unfortunately, pregnant drug abusing women in gen- eral are relatively non-compliant with family planning approaches (Armstrong et al., 1991). For women in the comprehensive program, 51% selected Norplant inser- tion after delivery as their method for subsequent fam- ily planning, with an additional 26% selecting tubal ligation (Jansson et al., in press). Effective long-term contraception can be expected to increase cost savings by increasing the interval between subsequent pregnan- cies.

Finally, additional benefits of drug treatment to mother and infant are expected that were not included in the present cost-benefit analysis. Previous research has estimated the extent to which drug treatment is associated with reductions in crime and acute and chronic illnesses (particularly HIV infection) (DesJar- lais et al., 1985). In the treatment group, 49% of women reported having engaged in prostitution (within 30 days of treatment enrollment) and 9% were HIV seroposi- tive. Thus, abstinence from drugs and safer sexual practices may further enhance cost savings through decreased risk behaviors for transmission of HIV infec- tion.

The present study also identified a number of clinical differences between treatment seeking and nontreat-

ment seeking pregnant drug abusing women. On aver- age, treatment seekers were older and better educated than nontreatment seekers, which has previously been reported by other investigators (Finnegan, 1994). Since substance abuse is a chronic relapsing disorder, this age difference suggests women may progress to a certain point in their addiction career before entering treat- ment. The educational difference, while statistically sig- nificant, may not be clinically significant (e.g. mean of 11.2 years for treatment subjects and 10.6 years for controls), as both groups on average presented with less than a high school education. In the future, it may be useful for treatment programs to examine the utility of incorporating GED education/instruction and job skills training programs in their general curriculum (Silver- man et al., 1996). Lack of such skills may limit long- term treatment success for this high-risk population.

4.1. Limitations

Several methodological issues suggest data from this study be interpreted with caution. First, women were not randomly assigned to treatment or no treatment. Ethically, random assignment cannot be implemented due to the risks associated with continued drug use during pregnancy. Although the treatment subjects were demographically similar to controls, the two groups differed on several important variables, with controls being younger, less educated and less likely to have used cocaine than treatment subjects. While ma- ternal and infant outcome was significantly different for the two groups even after statistically controlling for these initial differences, other differences may have existed between the two groups that were not assessed in the study. To the extent that such characteristics correlate with maternal and/or infant outcomes, they could account for some of the observed differences in outcome.

Second, data on subjects were collected from two different hospitals. While it is possible that differences in outcome in part reflect differences in hospital proce- dures (e.g. admission and discharge criteria, data collec- tion techniques), such differences are unlikely, given that the two hospitals are sister institutions within the same hospital system and protocols for NICU admis- sions were comparable for the two sites. Geographically the two hospitals are located three miles apart on the eastern side of Baltimore City and draw patients from the same catchment area. More importantly, all profes- sional staff in the NICU unit serving the treatment program hold joint academic appointments and con- duct clinical rotations at the sister hospital. In addition, all training of drug assessment specialists at the two hospitals was conducted by co-investigators in the present project. When non-drug primary admissions were compared at the two NICUs during the subject

113 D.S. Suikis et ~1. i Drug and Alcohol Dependence 45 (1997) 105- 1 I?

recruitment period, no significant difference was found in length of stay for neonates with the same range of birthweights (1265-3867 g), with mean length of stay of 14.75 days (S.D. 16.6) at the treatment NICU and 10.7 days (S.D. 8.2) at the control NICU.

Third, although demographic and drug assessment data were obtained on all treatment and control sub- jects during routine clinical assessment, more detailed information on drug use severity and psychosocial functioning was obtained for only half of each group. For both groups, administration of the detailed assess- ment battery was determined primarily by staff and patient availability and no subject refused the assess- ment if requested. No differences were found in demo- graphic and substance use characteristics of women receiving and not receiving the more detailed assess- ment battery. In particular, data on tobacco use by controls is needed. In a recent study, adverse neonatal outcomes were more closely associated with prenatal tobacco than prenatal cocaine, marijuana, or opiate use (Yawn et al., 1994). However, it is unlikely tobacco use explains the present results since almost all subjects in the treatment group (99%) were regular tobacco users at program admission. Patients were also excluded as subjects if the had less than two prenatal visits or attended less than 2 weeks of treatment (N= 78). Out- come data were available on 18 of these patients, with the remainder delivering elsewhere with no outcome data available. For these 18 patients, NICU admission rate was 26% (compared to loo/o for treatment subjects and 26% for control subjects). Mean length of NICU stay for all of their infants was 1.2 days (compared to 0.8 days for the treatment subjects and 10.2 days for the control subjects).

Finally, treatment subjects consisted of women who were active in treatment at the time of delivery. NICU data were not available for women who were enrolled in the treatment program but delivered at another hospital. Thus, it is unknown if women inactive in treatment at the time of delivery more closely resemble the control subjects. It is possible that some treatment is better than no treatment, with program dropouts showing improved outcomes relative to no treatment controls. Alternatively, it is also possible that treatment dropouts relapse to substance use and have outcomes similar to those of the no treatment control group. Additional research is needed to address this issue.

In summary, the study suggests that providing com- prehensive drug treatment and obstetrical care services for drug abusing pregnant women is associated with substantial cost savings in the care and treatment of the infants born to this high-risk population of women. For an investment of an estimated $6639 in drug treatment services during pregnancy, a net savings of an estimated $4644 in NICU costs per mother/infant pair per treat- ment episode was attained based on NICU costs of

$1200/day. More substantial savings would be made in hospitals that have higher NICU rates. Future research must address some of the methodological shortcomings of the present research. In particular, it is critical to determine if the amount of time in treatment affects cost savings.

Acknowledgements

This research was supported in part by Public Health Service grant NIDA P50 DA 09258 (Behavior Therapy Treatment Research Center) and NIDA Intramural Research funds. The authors wish to thank Lauren Jansson, MD, Cynthia Peterson, PhD and Patricia Paluzzi, CNM, MPH for their assistance in the devel- opment and implementation of the services in the treat- ment program. The authors also wish to thank Peter Rutigliano for the creation and maintenance of the treatment database.

References

Apsler, R. and Harding, W. (1991) Cost-effectiveness analysis of drug abuse treatment: Current status and recommendations for future research. Drug Abuse Services Research Series. Background Pa- pers on Drug Abuse Financing and Services Research, pp. 58-81. Washington, D.C, US Government Printing Office.

Armstrong, K.A., Kenen, R. and Samost, L. (1991) Barriers to family planning services among patients in drug treatment programs. Fam. Plann. Perspect. 23, 264271.

Bauman, P.S. and Levine, S.A. (1986) The development of children of drug addicts. Int. J. Addict. 21, 849-863.

Calhoun, B.C. and Watson, P.T. (1991) The cost of maternal cocaine abuse: I. Perinatal cost. Obstet. Gynecol. 78, 731-734.

Chasnoff, I.J. (1992) Cocaine, pregnancy and the growing child. Curr. Probl. Pediatr. 22, 302-321.

Cross, T., Saxe, L. and Hack, M. (1988) The effectiveness of treat- ment settings for cocaine and other non-opiate drugs. Bigel Institute for Health Policy.

DesJarlais, D.C., Joseph, H., Dole, V.P. and Nyswander, M.E. (1985) Medical maintenance feasibility study. In: Progress in the Devel- opment of Cost-effective Treatment for Drug Abusers (Ashery, R.S. ed.), NIDA Research Monograph 58, Washington, DC, Government Printing Office.

Finnegan, L. and Kandall, S. (1992) Maternal and neonatal effects of alcohol and drugs. In: Substance Abuse: A Comprehensive Text- book (2nd edition) (Lowinson, J., Ruiz, P., Milman, R. and Langrad, J., eds.), Williams and Wilkens, Baltimore, MD, pp. 628-656.

Finnegan, L. (1994) NIDA Perinatal 20: Treatment Outcome Find- ings. NIDA Technical Review Meeting, Palm Beach, Florida, June, 1994.

Fiscella, K. (1995) Does prenatal care improve birth outcomes? A critical review. Obstet. Gynecol. 85, 468-479.

Glantz, J.K. and Woods, J.R. (1993) Cocaine, heroin, and phency- clidine: obstetric perspectives. Clin. Obstet. Gynecol. 36, 2799301.

Goodman, A.C., Holder, H.D., Nishiura, E. and Hankin, J.R. (1992) An analysis of short-term alcoholism treatment cost functions. Med. Care 30, 7955810.

D.S. Svikis et al. /Drug and Alcohol Dependence 45 (1997) 105-l 13 113

Holder, H.D. (1987) Alcoholism treatment and potential health car cost saving. Med. Care 25, 52-71.

Holder, H.D. and Hallan, J.B. (1986) Impact of alcoholism treatment on total health care costs: A six-year study. Adv. Alcohol. Subst. Abuse Fall (6), I - 15.

Horgan, C., Rosenback, M., Ostby, E. and Butrica, B. (1991) Target- ing populations with drug abuse problems: Pregnant women. NIDA drug abuse services research series, pp. 1233 144, Washing- ton, DC.

Hubbard, R.L., Marsden, M.E., Rachal, J.V., Harwood, H.J., Ca- vanaugh, E.R. and Ginzburg, H.M. (1989) Drug abuse treatment. A national study of effectiveness. Chapel Hill: University of North Carolina Press.

Imaizumi, S. (1992) Perinatal factors that influence neonatal out- come. Identifing the needs of drug affected children: Public Policy Issues, pp. I l-23, Office of Substance Abuse Prevention Mono- graph, Washington, DC.

Jansson, L., Svikis, D., Lee, J., Paluzzi, P., Rutigliano, P. and Hackerman, F. (1997) Pregnancy and addiction: A comprehensive care model. J. Subst. Abuse Treat (in press).

Jones, C. and Lopez, R. (1990) Drug Abuse and Pregnancy. in: New Perspectives on Prenatal Care (Merkatz, I. and Thompson, J., eds.) Elsevier, New York, pp. 2733310.

Kandall, S.R. (1993) Improving treatment for drug-exposed infants. U.S. Department of Health and Human Services. U.S. Govern- ment Printing Office, Rockville, MD.

Kolar, A.F., Brown, B.S., Haertzen, CA. and Michaelsen, B.S. (1994) The life experiences of children of opiate addicts in metha- done maintenance. Am. J. Drug Alcohol Abuse 20, 59- I7 I.

MacGregor, S., Keith, L. and Chasnoff, I.J. (1987) Cocaine use during pregnancy: Adverse perinatal outcomes. Am. J. Obstet. Gynecol. 157, 686-690.

Matera, C., Warren, W.B., Moomjy, M., Fink, D.J. and Fox, H.E. (1993) Prevalence of use of cocaine and other substances in an obstetric population. Am. J. Obstet. Gynecol. 163. 7977801.

McLellan, A.T., Laborski, L., O’Brien, C.P. and Woody, G.E. (1980) An improved evaluation instrument for substance abuse patients: The Addiction Severity Index. J. Nerv. Ment. Dis. 168, 26633.

Miller, W.H. and Hyatt, M.C. (1992) Perinatal substance abuse. Am. J. Drug Alcohol Abuse IS, 247 -261.

Miller, W.R. and Hester, R.K. (1986) Inpatient alcoholism treatment: Who benefits? Am. Psychol. 41, 7944805.

Philbbs, C.S., Batema, D.A. and Schwartz. R.M. (1991) The neonatal costs of maternal cocaine use. J. Am. Med. Assoc. Ii, 52l- 1526.

Robins, L. and Mills, J.L. (1993) Effects of in-utero exposure to street drugs. Am. J. Public Health, 83.

Silverman, K., Chutuape, M.A., Svikis. D.S., Bigelow, G.E. and Stitzer, M.L. (1996) Incongruity between occupational interests and academic skills in drug abusing women. Drug Alcohol De- pend. 40, I I55 123.

Svikis, D.S. and Huggins, G. (1996) Substance Abuse in Pregnancy: Screening and Intervention. Contemporary OB/Gyn. 41, 32- 52.

White House (1989) National Drug Control Strategy US Government Printing Office, Washington, DC.

Yawn, B.P., Thompson, L.R., Lupo, V.R., Googins, M.K. and Yawn, R.A. (1994) Prenatal drug use in Minneapolis-St. Paul, MI. A four year trend. Arch. Fam. Med. 3, 520 527.

Zuckerman, B. and Bresnahan, K. (1991) Developmental and behav- ioral consequences of prenatal drug and alcohol exposure. Pedi- atr. Clin. North Am. 38, 1387 -1407.