The effects of infants' illness on mothers' interactions with prematures at 4 and 8 months

INFANT

BEHAVIOR

AND

DEVELOPMENT

12, 25-35 (1989)

The Effects of Infants’ Illness on Mothers’ Interactions with Prematures at 4 and 8 Months PATRICIA A. JARVIS State University of New York, Plattsburgh BARBARA J. MYERS Virginia Commonwealth University GARY L. CREASEY University of Vermont This investigation explored the effects of illness on mother-infant interactions among three groups of prematures: infants with bronchopulmanary dysplasia (BPD), infants with re?piratary distress syndrome (RDS), and infants with no serious medical complications. Mother-infant interactions were coded from videotapes of teaching sessions at 4 and B months (correcting for prematurity). As predicted, BPD infant-mother pairs had less optimal interactions than RDS pairs and healthy preterm infant-mother dyads. The results of the present study demonstrated the importance of severity of illness not only for health status but also far mother-infant interactions.

prematurity

bronchopulmonary

dysplasia

social

interactions

The effect of premature birth on infant development has been a focus of much concern over the past 2 decades as neonatal intensive care procedures have markedly increased the survival rates for such infants. Research on the development of premature infants has been concerned primarily with the physical This article is based on a dissertation submitted to Virginia Commonwealth University by the first author under the direction of the second author in partial fulfillment of the requirements for the doctoral degree. It was funded by a March of Dimes Social and Behavioral Sciences Research Grant #12-l% awarded to the second author. Portions of this research were reported at the 1986 and 1987 meetings of the Eastern Psychological Association. Special gratitude is extended to the families who participated in this research and to the staff at the Medical College of Virginia Hospital for allowing the authors to visit infants artd mothers in the Neonatal Intensive Care Unit there. Gratitude is also extended to the undergraduate lab assistants who participated in coding the data from this study: Susan Hastoglis, Alexandra Spaith, Valerie Brice, Nancy Van de Meulebroecke, Michele Samuels, and Marie Farmer. Correspondence and requests for reprints should be sent to Patricia A. Jarvis, Department of Psychology, State University of New York, Plattsburgh, NY, 12901.

25

26

JARVIS,

MYERS,

AND

CREASEY

and mental development of such infants (Goldberg, 1978). More recently, however, the effects of prematurity on maternal-infant interactions have been examined (Beckwith & Cohen, 1978; Kopp & Krakow, 1983). Generally it has been found that there are more interactional problems in premature than fullterm infant-mother dyads (Field, 1980; Goldberg, 1978). Two major findings have emerged regarding premature infant-mother social interactions. First, premature infants have been found to be less alert, less active, and less responsive than full-term infants through the first few months of infancy (Bakeman & Brown, 1980; DiVitto &Goldberg, 1979; Field, 1977). This finding was consistently obtained in studies utilizing diverse observational measures and situations (e.g., social interactions and feeding episodes) and diverse populations (e.g., black, low-socioeconomic status (SES); white, middle-SES). For most, but not all, investigations, premature and full-term groups were equated on gestational age. Second, although some data exist indicating that mothers of preterms are less actively involved with their infants (DiVitto & Goldberg, 1979), by 4 months, mothers of premature infants have been found to stimulate their infants more than do mothers of full-terms (Bakeman & Brown, 1980; Field, 1979). This latter finding indicates that mothers of prematures increase their efforts to elicit responses from their less active infants. Yet, Field (1977) found that premature infants in her investigations displayed more gaze aversion and inattention than full-term infants, suggesting that greater maternal activity represents overstimulation for these infants. These findings suggest that during early infancy mothers and their premature infants have difficulty striking a balance socially: The actions of one member of the dyad affect the actions of the other in an asynchronous way. In considering a transactional model of development, biological issues must be considered as well as environmental issues (Sameroff & Chandler, 1975). Some research has attempted to view illness status as a mediator in premature outcomes. For example, DiVitto and Goldberg (1979) identified interactional differences between premature infant-mother dyads and full-term infantmother dyads related to illness status. In their study, full-term infants were compared to healthy prematures, sick prematures (with respiratory distress syndrome), and infants of diabetic mothers. Partial support was found for the hypothesis that the groups would order themselves on behavioral competence depending on the severity of newborn illness. This study was important for identifying differences between premature and full-term infants that may have affected subsequent behavior. However, it did not distinguish whether immaturity, illness, or their interaction were most influential in affecting subsequent infant and maternal behavior. Specifically, illness and prematurity were confounded because prematures with respiratory distress syndrome were younger than healthy prematures (i.e., the groups were not matched for gestational age).

PREMATURITY

AND

ILLNESS

27

Field (1977) compared 12 premature infants with mild to moderate respiratory distress syndrome (RDS) to 12 post-term postmature infants and 12 healthy full-term infants, and found that mothers of healthy infants were less active and modified their level of activity depending on whether the infant was gazeaverting or gaze-attending. The mothers of preterm infants failed to vary their activity on the basis of the infants’ cues. They worked hard trying to get responses whether the infant was receptive to their stimulation or not. This research suggests that sick premature infants are behaviorally less competent and responsive than full-term infants and that parents must compensate for this by working harder in order to sustain the relationship. According to Sostek, Quinn, and Davitt (1979), the added stress of postnatal illness may affect infant behavior as well as the caregiver’s behavior toward the child. For example, Beckwith and Cohen (1978) assessed parentinfant interactions in naturalistic home observations with premature infants at 1 month corrected age who varied in the amount of initial medical complications (as assessed by the Obstetrical Complications Scale and the Postnatal Complications Scale). They found that infants who had more postnatal medical problems received more overall caretaking behavior. In contrast, Minde, Whitelaw, Brown, and Fitzhardinge (1983) observed mother-infant interactions in three groups of premature infants (well, moderately ill, and sick) 1 month after discharge. They found that mothers of sick infants displayed less interactive behavior, whereas mothers of moderately ill infants responded positively to their children. As Greene, Fox, and Lewis (1983) have suggested, it is important to sort out differences in infant and maternal behavior due to transient illness (such as respiratory distress) versus longer-term organic problems. Infants who were ill postnatally but who suffer no apparent handicap may recover behaviorally; mothers of infants who were sick, however, may continue to treat their infants differently because of the initial illness and possibility of handicap. The purpose of the present study was to extend previous research findings regarding mother-infant interactions with prematures and to evaluate the role played by varying degrees of respiratory illness. To accomplish this goal, three groups of premature infants were compared: Severely ill prematures (with bronchopulmonary dysplasia or BPD), moderately ill prematures (with RDS), and healthy preterms (with no serious medical complications). At 4 and 8 months of age (correcting for prematurity), mother-infant interactions were observed in standardized teaching situations which were videotaped for later analyses using the Nursing Child Assessment Teaching Scale (Barnard & Bee, 1979). It was hypothesized that the infants with BPD would show less optimal development and would be poorer participants in interactions with their mothers than infants in the other two groups due to their illness status. This hypothesis was partially based on the fact that such infants were connected to

28

JARVIS,

MYERS,

AND

CREASEY

several life-support systems for a long period of time and thus their physical confinement would affect their ability to actively participate in teaching interactions. It was hypothesized that the RDS and healthy preterm infant-mother pairs would also differ, with healthy preterm infants being slightly better participants in interactions than RDS infants. This difference was expected to lessen from 4 to 8 months as RDS infants were expected to “catch-up” to healthy preterms. However, BPD infants were not expected to improve significantly enough to be equated with either of the other two groups from 4 to 8 months due to the severity and length of their illness. METHOD Subjects Three groups of premature infants were assessed in the present study: (a) infants with BPD (n = 19); (b) infants with RDS (n = 16); and (c) healthy preterms with no serious medical complications (n = 13). Prematurity was defined as a birth weight of less than 2500 gms and a gestational age of less than 37 weeks (determined by Dubowitz exam). Infants were not included in the study if they had physical anomalies present at birth, if their parents were unable to visit them at the hospital, if they had neurological or sensory handicaps, or if they suffered Grade IV (very serious) intraventricular hemorrhage. Diagnosis of BPD included the following criteria: (a) primary lung disease requiring positive pressure ventilation within the first 3 days of life; (b) continued respiratory insufficiency because of pulmonary pathology requiring oxygen supplementation to maintain pa02 > 50 mm Hg beyond 30 days of life; and (c) radiographic changes progressing to a pattern of alternating areas of focal emphysema and atelectasis persisting for at least 30 days (Northway, Rosan, & Porter, 1967). Premature infants with RDS required mechanical ventilation for at least the first 3 days of life but did not go on to develop BPD. The RDS infants were diagnosed by the neonatologist on the basis of hypoareation, air bronchograms, and radiologic findings indicating a ground-glass appearance to the parenchyma. The healthy preterms were premature infants whose hospital course was free of major complications (i.e., respiratory distress, intracranial hemorrhage, necrotizing enterocolitis, physical anomalies, etc.). This group served as a control group because there is evidence that general developmental outcomes (including quality of mother-infant interactions) of healthy prernatures are similar to those or normal full-term infants (Eaves, Nuttall, Klonoff, 8c Dunn, 1970; Hunt dc Rhodes, 1977; Sigman & Parmelee, 1979; Weiner, Rider, Oppel, Fischer, & Harper, 1965). Only the smallest well prematures were recruited for the study to keep the gestational ages and birth weights across the three groups as close as possible. The group was the hardest to establish, as infants who are born verv early with low birth weight generally do develop medical complications.

PREMATURITY

AND

ILLNESS

29

The well group was smaller from the start, then, as appropriate infants were not available. It also experienced more subject attrition (from 12 infants at 4 months to 7 infants at 8 months) despite repeated attempts at scheduling appointments. Because these infants recovered so well medically from their premature birth, their parents were less motivated to maintain ties with the medical staff or our research team. Subject recruitment occurred as the infants approached term age and once group membership became clear. A neonatologist in the Neonatal Intensive Care Unit (NICU) identified potential subjects, invited participation, and obtained informed consent. The NICU facility in the present study is a 48-bed unit which serves over 800 infants a year. The demographic backgrounds of the patients are diverse because the NICU is a regional center serving a large portion of central Virginia. Although a complete case-matching procedure was not possible due to an insufficient patient population, an attempt was made to keep all three groups as near equal as possible on (a) birth weight, (b) gestational age, (c) maternal marital status, (d) race, (e) maternal age (mothers less than 17 years of age were not included), (f) maternal education, and (g) socioeconomic status, as measured by the Hollingshead Scale (Hollingshead, 1975). Table 1 gives the means and standard deviations for the matching variables and the ANOVA results. Mean Family Hollingshead scores were 3.0 for the BPD group, 2.9 for the RDS group, and 2.8 for the healthy preterm group. The groups were not signficantly different on any of these variables except birth weight. The healthy preterms had higher birth weights than the BPD group. Birth weight was confounded with illness for the BPD group in that BPD infants had lower birth weights than their matched well controls. This was because perfect oneto-one matching was not always possible and birth weight was the variable most difficult to equate between well and sick infants. Small for gestational age infants were not included in the study. Materials The Nursing Child Assessment Teaching Scale (NCATS; Barnard & Bee, 1979) was administered to all infant-mother dyads at 4 and 8 months of age (correcting for prematurity). This scale gives a global measure of the reciprocity of the mother-infant pair in a brief (5-min) episode. The scale consists of 73 yes-no items organized into 6 subscales, 4 of which describe the mother’s behavior and 2 of which describe the infant’s behavior. The first subscaleis parent’s sensitivity to child’s cues, and the items deal with the parent’s ability to accurately read the cues given by the infant. A sample item from this subscaleis: Parent pauses when child initiates behavibrs during the teachingepisode.The

secondsubscaleis parent’sresponseto child’s distress,and the items dealwith the parent’s abilities to recognize that distress is occurring, determine the appropriateaction which will alleviate distress,and then do that action. A sample item is: Rearrangesthe child’s position and/or task materials. The third

Note.

Observed Observed

Frequency

There

were

in hospital at home

no significant

differences

20 2 between

2.6

13.5

Maternal

education

2.7 405 5.9

(weeks)

1186 24.5

Gestational

31.2

age

BPD (n=19) M SD

Birth weight (grams) Maternal age

Variable

the

three

16 2

12.7

1516 26.5

31.1

groups.

1.8

591 2.9

2.9

RDS (n=17) M SD

TABLE 1 Matching Variables

2.1

11.6

8 5

2.2 254 6.2

SD

1616 25.2

(n=13)

32.6

Well M

(252)

cw3 PM) C&W (239)

Between-Group df

2.99

0.83

0.94 0.31

1.35

F

.059

.443

.396 .736

.269

Differences p-value

PREMATURITY

AND

ILLNESS

31

subscale is social-emotional growth fostering, and the items deal with global parent adaptation in terms of providing social reinforcement of desirable behaviors. A sample item is: Parent praises child’s efforts or behaviors broadly (in general) at least once during the episode. The fourth subscale is cognitive growth fostering, and the items deal with the parent providing cognitive stimulation for the child. A sample item is: Parent praises child’s efforts or behaviors broadly (in general) at least once during the episode. The fourth subscale is cognitive growth fostering, and the items deal with the parent providing cognitive stimulation for the child. A sample item is: Parent uses both verbal description and modeling simultaneously in teaching any part of the task. The fifth subscale is clarity of cues, and the items deal with the child’s skill and clarity in sending cues to the parent. A sample item is: Child vocalizes while looking at the task materials. The last subscale is responsiveness to parent, and the items deal with the child’s ability to respond to behavioral cues of the parent. A sample items is: The child looks at the parent’s face or eyes when parent attempts to establsh eye-to-eye contact. The score is a raw score and the subscales were summed for a total interaction score for the dyad. In developing this instrument, the test developers assessed a pilot sample of 922 infant-mother dyads. A reliability rate of 85% agreement with a partner was readily achieved by trainees. Internal consistency using Cronbach’s alpha for the total score is .73 for the Teaching Scale for infants under 12 months (Barnard & Bee, 1979; Barnard, Eyres, Lobo, & Snyder, 1983). This scale was used in the present sudy because it was judged to be the best available standardized instrument for measuring both the infant’s and the caretaker’s contribution to a dyadic relationship. Procedure Mother-infant dyads were filmed for 5-min teaching sessions when infants were 4 and 8 months corrected age. At each observation, the mother was asked to hold the child in her lap and to teach the child two tasks (a red ring and a bell) chosen from the Bayley Scales of Infant Development (Bayley, 1969). The first task was age-appropriate and the second task was several months in advance of the child’s age (see Barnard, Bee, & Hammond, 1984). The filming took place at the Medical College of Virginia Hospital or during home visits with those families who were unable to come to the hospital. Eighty-two percent of the observations were made at the hospital. The three groups were not significantly different with respect to hospital versus home testing (see Table 1 for ANOVA results). All videotapes were scored using the. NCATS by two or more trained observers blind to infants’ group status. Interrater reliability was assessed by subtracting the number of items two observers disagreed on from the total number of items and dividing by the total number of items (as described by Barnard & Eyres, 1979). A reliability rate of better than 93% agreement with a partner was achieved.

32

JARVIS,

Group

Meons

for

MYERS,

the

TABLE Teaching

AND

CREASEY

2 Scales

(4 ond

8 Months) 4 Months

Subscales 1) Sensitivity to cues 2) Response to distress 3) Social-emotional growth 4) Cognitive growth 5) Clarity of cues 6) Responsiveness Total

fostering

fostering to parent

score

BPD M

(n=16)

SD

M

9.2 0.0 8.1

1.3 2.5 2.0

11.1 8.1 0.5

2.6 0.9 2.1

52.4

7.0

RDS

(n=lB) SD

Well M

(n=12) SD

10.0 qo.1

1.1 1.3

9.0 10.0

1.1 1.6

9.1 12.2 8.1

1.8 3.1 1.5

7.0 10.0 7.5

1.9 3.1 2.1

8.2

3.3

6.0

3.8

57.0

0.3

51.1

10.3

8 Months BPD

(n=15)

Subscoles

M

SD

RDS M

(n=14) SD

Well M

(n=7) SD

1) Sensitivity to cues 2) Response to distress 3) Social-emotional growth

8.3 a.4 6.6

1.6 2.0 2.3

9.6 10.7 9.0

1.2 0.9 1.9

9.4 10.0 7.5

0.9 1.9 2.2

4) Cognitive growth fostering 5) Clarity of cues 6) Responsiveness to porent

10.0 a.7 7.3

3.6 1.2 2.9

12.4 8.9 9.0

3.4 1.3 4.1

11.2 0.0 7.1

3.4 1.1 2.6

Total

49.4

9.2

59.7

0.0

53.4

0.2

score

fostering

RESULTS

Total interaction scores for the NCATS were calculated as well as subscale interaction scores for each dyad in each of the three groups (BPD, RDS, and healthy preterms). The group means and standard deviations are shown in Table 2. Total scores for the Teaching Scale in the present study were analyzed using a multivariate 3 (Group: BPD, RDS, and Well) x2 (Time: 4 and 8 months) analysis of variance which revealed a significant Group effect, F(2,77) = 3.64, pC .03. Post-hoc comparisons revealed that mothers and infants in the BPD group and in the healthy preterm group scored lower on the NCATS than mother-infant dyads in the RDS group, p< .05. Based on the Group effect found for total scores, individual subscale scores were analyzed. For Subscale 1, parent’s sensitivity to child’s cues, a significant Group effect was obtained, F(2,77) = 3.24, p< .04. Analyses of the total interaction scores revealed a significant Group effect, F(2,77) = 3.64, pC .03. Post-hoc test revealed that mothers with infants in the BPD group were less sensitive to their infant’s cues than mother-infant dyads in the other two groups, pC .05.

PREMATURITY

AND

ILLNESS

33

For Subscale 2, parent’s response to child’s distress, a significant Group effect was again obtained, F(2,77) = 5.38,~~ .007. Neuman-Keuls post-hoc tests of the means revealed that mothers of BPD infants were less responsive to their infant’s distress than mothers of either RDS or healthy preterms on both subscales, p< .05. Neither the Time effects nor the interaction effects were significant for these subscales. For Subscale 3, social-emotional growth fostering, a significant Group effect, F(2,77)=3.84, p< .02, and a significant Time effect, F(2,77) =4.85, p< .03, were obtained. Post-hoc analysis of the Group effect revealed that mothers of BPD infants fostered their infant’s social and emotional growth less than mothers in the other two groups, p< .05. Similar analysis of the Time effect indicated that mothers of BPD infants worsened in their social-emotional growth fostering from 4 to 8 months, whereas mothers of RDS infants improved in their social-emotional growth fostering from 4 to 8 months, p< .05. Mothers of well infants neither improved nor worsened from 4 to 8 months in their scores on this subscale. The interaction effect failed to reach significance. There were no significant differences between the groups on Subscales 4, 5, and 6. DISCUSSION The results of the present study indicated that degree of illness in premature infants did make a difference in how mothers and infants interacted at 4 and 8 months. The sickest group of infants (BPD infants) generally had lower scores on the NCATS than the other two groups (RDS or well infants) on this scale. These differences were restricted to scales reflecting the mothers’ behaviors as opposed to the children’s behaviors. Mothers of the sickest infants were less sensitive to their infants’ cues, did not respond as well as mothers in the other two groups to their infants’ distress, and did not foster social-emotional growth in their infants as much as mothers in the other two groups. In addition, mothers of BPD infants showed a consistent decline in these behaviors from 4 to 8 months, whereas mothers of RDS infants (moderately sick infants) improved on these behaviors from 4 to 8 months. These results may be interpreted as indicating that mothers of moderately ill premature (RDS) infants try harder to interact with their infants regardless of the infants’ responses to their efforts. Such was the interpretation of Field (1977) who found that mothers of RDS compared to mothers of well prematures failed to adjust their activity on the basis of their infants’ cues. This was supported in the present study. The consistent finding that mother-infant dyads in the RDS group performed better on the NCATS than such dyads in the healthy preterm group may be due to a possible hidden variable such as more frequent visits to the hospital by mothers in the RDS group than mothers in the healthy preterm

34

JARVIS,

MYERS,

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CREASEY

group. Data on the number of visits to the hospital were not obtained in the present study. However, it might be a reasonable hypothesis that if mothers of RDS infants more frequently visited their infants, they might be more familiar with the infants’ cues and score higher on interaction measures such as the NCATS than even mothers of healthy preterm infants. That there were more differences for the mothers’ behaviors than for the infants’ behaviors overall supports this. However, the lack of infant differences in this study may have been due to the fact that there are fewer scales assessing infant behaviors compared to those assessing mother behaviors (6:2). This research is essential for determining the behavioral significance of early illness on later social and cognitive development which has been hypothesized so often in previous research. Longitudinal research comparing very sick, moderately sick, and healthy preterms (and healthy full-term infants) is necessary for assessing the long-term consequences of illness on behavior. This study has revealed that, although a BPD infant may be medically stable enough to go home from the hospital, the mother of such an infant is behaviorally not the same as the mother of a healthy preterm infant or even a moderately sick infant. Social interactions by the mother will be different. These variations in mother-child interactions persist beyond the neonatal period and in the present study were still present at 8 months for the BPD group.

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Field, T.M. (1979). Interaction patterns of preterm and term infants. In T.M. Field, A.M. Sostek, S. Goldberg, & H.H. Schuman (Eds.), Infonts born af risk: Behavior and development. New York: Spectrum. Field, T.M. (1980). Interactions of high risk infants: Quantitative and qualitative differences. In D.B. Sawin, R.C. Hawkins, L.P. Walker, & J.H. Penticuff (Eds.). Excepfionul infun!. (Vol. 4): Psychologicul risks in infunt-environmental trunsuctions. New York: Brunner/ Mazel. Goldberg, S. (1978). Prematurity: Effects on parent-infant interaction. Journul of Pediutric Psychology, 3, 137-144. Greene, J.G., Fox, N.A., & Lewis, M. (1983). The relationship between neonatal characteristics and three-month mother-infant interaction in high-risk infants. Child Developmenf, 54, 1286-1296. Holhngshead, A.B. (1975). Four-Factor Index of Social Status. Unpublished Manuscript. Yale University, Department of Sociology, New Haven, CT. Hunt, J.V., & Rhodes, L. (1977). Mental development of preterm infants during the first year. Child Development, 48, 204-210. Kopp, C.B., & Krakow, J.B. (1983). The developmentalist and the study of biological risk: A view of the past with an eye toward the future. Child Development, 54, 1086-1108. Minde, K., Whitelaw, A., Brown, J., & Fitzhardinge, P. (1983). Effect of neonatal complications in premature infants on early parent-infant interactions. Developmentul Medicine and Child Neurology, 25, 763-777. Northway, W.H., Jr., Rosan, R.C., &Porter, D.Y. (1967). Pulmonary disease following respirator therapy of hyaline membrane disease. New England Journal of Medicine, 276, 357. S.ameroff, A.J., & Chandler, M.J. (1975). Reproductive risk and the continuum of caretaking casualty. In F.D. Horwitz (Ed.), Review of child development reseurch. Chicago: University of Chicago Press. Sigman, M., & Parmelee, A.H. (1979). Longitudinal evaluation of the preterm infant. In T.M. Field, A.M. Sostek, S. Goldberg, & H.H. Shuman (Eds.), Infonts born at risk: Behuvior and development. New York: Spectrum. Sostek, A.M., Quinn, P.O., & Davitt, M.K. (1979). In T.M. Field, A.M. Sostek, S. Goldberg, & H.H. Shuman (Eds.), Infunls born al risk: Behavior und Development, New York: Spectrum. Wiener, G., Rider, R.V., Oppel, W.C., Fischer, L.K., & Harper, P.A. (1965). Correlates of low birth weight: Psychological status at six to seven years of age, Pe&ztrics, 43~. 6 April

1988;

Revised

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1988

n