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Home > RNJ > 2005 > September/October > Severity of Illness, Functional Status, and HRQOL in Youth with Spina Bifida

Severity of Illness, Functional Status, and HRQOL in Youth with Spina Bifida
Robin R. Leger, PhD MS RN CCRP

Knowledge regarding the health status, functional status, and health-related quality of life (HRQOL) of youths with spina bifida is important in promoting optimal health care and preventing secondary conditions. A descriptive study using a convenience sample of 60 youth (15- to 25-year olds) with spina bifida from the northeastern United States was conducted to examine the relationship among health status (severity of illness), functional status, and HRQOL. The findings indicated that 28% (n = 17) of the youths were healthy other than having spina bifida, 72% (n = 43) reported secondary health conditions, and 32% (n = 19) reported additional comorbid conditions. The sample reported a high level of functional status on the FIM; the mean was 116.8 (SD = 7.07, range = 90–126). Bowel and bladder incontinence, the inability to traverse stairs, and select memory deficits were identified as more frequent functional limitations. The youth reported a high level of HRQOL; mean was 200.8 (SD = 19.54, range = 155–232). A regression analysis was performed, with HRQOL entered as the criterion; the results were not statistically significant (r2 = .02, df = 2, 57, p = .57). The researcher concluded that youths with spina bifida reported a high level of satisfaction with HRQOL, are succeeding at college, participating in recreation, sport activities, and other aspects of young adult living, and yet they are experiencing a number of secondary health conditions that leave them with concerns for their future.

Few primary or specialty health professionals have had training in the care of patients with pediatric-onset neuromuscular conditions, in particular, adults with spina bifida. Therefore, the ability of healthcare providers to suggest preventive measures, anticipatory guidance, and wellness approaches to care for individuals with lifelong chronic illness and disability is limited. Healthcare providers need to collaborate with rehabilitation specialists to promote a life span approach to living well with disability that is based on empirical studies that describe their primary and secondary health conditions over time.

Along with advances in health care and technology, youth with spina bifida in the United States have had advantages over the past few decades such as mainstreaming initiatives, additional opportunities to participate in community activities, and legal policy changes made effective by the Americans with Disability Act of 1990. The promotion of quality of life in patients with chronic health conditions has become a priority focus of healthcare providers and researchers. A consensus statement from the American Academy of Pediatrics, American Academy of Family Physicians, and American College of Physicians–American Society of Internal Medicine (2002) heralds the need for programs of outcomes research and efforts to facilitate the transition to adult healthcare for youth with chronic and disabling conditions. Because of the relative lack of studies on youth with spina bifida, the primary aim of this study was to describe the health status, functional status, and health-related quality of life (HRQOL) of a sample of youth (15–25 years) with spina bifida in the Northeast.

Literature Review

There are few studies in the literature that describe health status, functional status or HRQOL associated with spina bifida. Knowledge is limited in how to prevent secondary conditions of spina bifida and cope with increased disability over a life span. Although 85% of individuals affected typically will have shunted hydrocephalus (Lazzareti & Pearson, 2004) and approximately 40% will have latex allergy (Meeropol, 2001), many will be at risk for developing chronic renal failure, pressure sores, and other chronic disabling conditions that may be preventable (Bryan, 1998; Lollar, 1994; Simeonsson, McMillen, & Huntington, 2002).

A review of the literature on spina bifida reveals that few studies measure its severity or secondary conditions. Kinsman and Doehring (1996) described 353 admissions of patients with spina bifida over an 11-year period and classified the conditions for which they were admitted as potentially preventable and not preventable. In another study of 111 adolescents and adults with spina bifida at three clinics in New England, more than 100 different International Classification of Disease (ICD) codes were identified in patients followed across inpatient and ambulatory settings (Leger, Burke, Dunleavy, & Engelmann, 1998). A need for a comprehensive method and measure of primary and secondary health conditions for this aging population was evident.

In an Australian study, a 3-point severity-of-illness index was used with 46 young people (14–23 years) with spina bifida (Sawyer & Roberts, 1999). A similar severity-of-illness measure was developed from the medical records of 59 children in the United States with spina bifida (Lemanek, Jones, & Lieberman, 2000). This disease parameter scale included the five variables of spinal cord lesion level (four categories), presence or absence of a shunt, number of shunt replacements and surgeries, number of other surgeries, and ambulation status (four categories). The scale was later used as a severity index to categorize children aged 3–16 years into one of three groups—mild, moderate, or severe. Researchers noted that age was statistically correlated with medical severity (r = .37, p < .05; Lemanek, Jones, & Lieberman, 2000). These two severity-of-illness scales have the limitation of being strong in specificity but weak in sensitivity. Both scales overlook less frequently experienced conditions and allow for underreporting of health status and risks for secondary conditions.

Studies on functional status in youths with spina bifida are mostly clinical in nature and have not been used empirically to explore relationships with other factors. One Italian study evaluated the relationship of disability and HRQOL of 12 patients aged 14–18 years with spina bifida using the Functional Independence Measure (FIM; Uniform Data System for Medical Rehabilitation, 1996) and the Barthel Index to assess disability and the Medical Outcomes Study 36-Item Short Form Health Survey (SF-36) to measure HRQOL (Padua, et al., 2002). They were unable to correlate relationships between the main measures or with the independent variables of age, gender, or educational level in this underpowered sample of 12 patients.

Although a growing body of literature exists on the HRQOL among diverse groups of people, only recently have there been publications of studies of populations with congenital or pediatric-onset chronic illness (Drotar, 1998). The self-reported Quality of Life in Spina Bifida Questionnaire Part 2 (QOL in SB, P2) was developed as a disease- and age-specific measure on a random sample of 89 youth aged (13–20 years) in Canada. The scores ranged from 98–225 (mean = 182, SD = 30) with a Cronbach’s alpha of 0.93, and the construct validity correlation was 0.37 (Parkin et al., 1997). In a follow-up study, the newborn neurophysical examination (NPE) was used as a severity of illness measure to assess the relationship of quality of life and parental hope in 137 families of children (aged 5–12 years) and 74 families of adolescents (aged 13–20 years) with spina bifida (Kirpalani et al., 2000). The NPE was obtained from newborn hospital records and included head circumference and percentile at birth, presence or absence of congenital anomalies, and level of spinal cord lesion (judged by references to sensory function, muscle enervation level, muscle power, and the presence or absence of an anal wink). This study did not use a composite score for health status but used only two variables—level of lesion and presence or absence of congenital anomalies for predicting HRQOL. Less frequently associated conditions or comorbidities were not taken into account, thus suggesting that conditions that could affect HRQOL may have been underreported. The two statistically significant associations noted in the sample of 74 youths (aged 13–20 years) with spina bifida were parental hope (r2 = .07, p < .05) with bowel function (control) and HRQOL (r2 = .23, p < .01; Kirpalani et al., 2000). Various patterns of impairments and coexisting disabilities in youths with spina bifida may be predictors of functional status and perceptions of quality of life. The recent publications on the development of spina bifida specific measures (Kirpalani et al., 2000; Lemanek et al., 2000; Parkin et al., 1997; Sawyer & Roberts, 1999) provide a starting point for further research in this area.

Methods

A descriptive correlational design was used to examine the relationships among health status, functional status, and HRQOL in youth with spina bifida. For this study, 60 youth with spina bifida were asked to complete a questionnaire packet containing the QOL in SB P2 (Parkin et al., 1997), the Health Status in Spina Bifida form (Leger, 2003), and the Youth with Spina Bifida Demographic form (Leger, 2003). All participants were assessed using the FIM (Uniform Data System for Medical Rehabilitation, 1996).

Sample

Data were obtained from a convenience sample of 60 youths (aged 15–25 years) with spina bifida who had a congenital thoracic- or lumbar-sacral-level myelomeningocele and were literate in English. Exclusion criteria included youths who were unable to self-report, who were unable to correctly answer two questions on the Mini-Mental State Examination (Folstein, Folstein, & McHugh, 1975), or who were currently experiencing an acute health crisis or receiving inpatient care. Individuals from the Northeast Myelodysplasia Association (NEMA) area (New England, New York, and northern New Jersey) were invited to participate. NEMA is a 20-year-old subcommittee of the Maternal Child Health Bureau’s (MCHB), New England Regional Genetics Group whose members include nurses, other health professionals, and individuals with spina bifida and their families.

Settings

Potential participants received researcher contact information through announcements in state and regional newsletters and meetings. Arrangements were made to meet for the study visit at a mutually agreed-upon time, date, and location; however, the participant’s home was the preferred location (Drotar, 1998). Other locations included quiet areas in college student unions, public libraries, gymnasiums, and tracks. The questionnaires and informed-consent forms were mailed to participants ahead of the visit along with an instruction sheet encouraging their completion in a quiet, comfortable setting. Family members or a friend were allowed to be present during the FIM assessment. The data collection process lasted less than 2 hours.

Instruments

Descriptive data gathered on a precoded spina bifida demographic form (Leger, 2003) included age, gender, educational status, employment status, driving status, social and recreational activities, and living arrangements and were adapted from an instrument developed for a federal MCHB grant to appraise the transition needs of 111 participants with spina bifida aged 17 to 55 years (Leger et al., 1998). Health status was determined by self-reported conditions on the Health Status in Spina Bifida Index (Leger, 2003), which includes 22 conditions identified by reviewing primary and secondary diagnoses (ICD-9s) of 111 participants with spina bifida, followed over a 3-year period in three clinics (Leger et al., 1998). Content validity was established by surveying a 10-nurse expert panel that had > 70% agreement on three condition categories—typical, advanced pathology, or comorbid—and established a total composite score of 1–6 (score of 1 indicating the best health status). The 18-item FIM uses a 1–7 Likert scale to assess disability that can reach a total score of 126; higher scores indicate higher functional status. The QOL in SB P2 is a one-dimensional measure developed for adolescents with spina bifida composed of 47 questions (Likert scale of 1–5, with higher scores indicating a higher quality of life) on health, life, self-concept, skills, and well-being (Parkin, et al., 1997).

Statistical Analysis

The sample size of 60 was determined based on two predictors, severity of illness and functional status, to achieve a median effect size at the 0.05 level of significance. The reliability of each of the study’s instruments was established (Table 1). Data analysis was completed using the SPSS statistical program. Measures of central tendency were computed to determine the normality of the distributions and the possible need for transformation and to examine functional status and HRQOL in youths with spina bifida. Pearson product correlations were computed to examine the relationship of the independent variables to the dependent variable, HRQOL. A multiple regression analysis was performed to examine the contribution of the predictors of HRQOL. An alpha level of 0.05 was chosen as the level of statistical significance for all analyses.

Instrument Reliability

The means, standard deviations, and ranges for the scores and alpha reliability on the psychometric instruments are presented in Table 1. Cronbach’s alpha reliability coefficients were determined to evaluate the internal consistency of the instruments. An alpha coefficient of 0.70 or higher is generally acceptable for social science research (Nunnally, 1978). The alpha coefficient for the FIM was 0.85. The mean of item correlation was 0.48. The corrected item correlations for comprehension (r = .06) and social interactions (r = .07) were the lowest, supporting previous reports that visual acuity, cognition, and social skills may not correlate with independence in physical mobility and bowel and bladder control. Deletion of the FIM items would not have lowered the scale reliability below 0.82. The alpha coefficient for HRQOL was 0.92, indicating high levels of internal consistency and corrected item correlations ranged from 0.06 to 0.71.

Results

Of the 60 youths who participated, the mean age was 18.95 years, SD = 2.8, (range of 15–25 years). Fifty-two percent (n = 31) were male and 48% (n = 29) were female. In terms of ethnicity, 85% (n = 51) were White, 10% (n = 6) Hispanic, and 5% (n = 3) Black. Forty-three percent (n = 26) of the participants had private insurance coverage, 22% (n = 13) had state Medicaid, and 35% (n = 21) reported having other coverage. The majority of the participants (77%; n = 46) lived with at least one parent and another 15% (n = 9) reported they lived at college. A few reported living in other arrangements, for example, one female was married and lived with her spouse. In terms of satisfaction with living arrangements, 52% (n = 31) were very satisfied, 23.3% (n = 14) said that living arrangements were adequate for now, 23.3% (n = 14) said they were thinking of changing. No participants reported that their arrangements were unsatisfactory. Ninety-five percent of participants said their home entries were accessible; however, access to bathrooms, kitchen area, and laundry rooms was limited. Twenty-five percent reported they would be interested in looking for more physically accessible housing in the future.

Seventy-five percent (n = 45) of the youths were in school, with 43% (n = 26) attending high school or vocational programs, and 33% (n = 20) in college. The current or highest grade completed was a bachelor’s degree in college (n = 2), and two participants were enrolled in graduate school. Twenty-six percent (n = 16) were unemployed and not planning to work, 33% (n = 20) worked part time, and 5% (n = 3) worked full time. The usual modes of transportation described were rides with others (72%; n = 43), driving themselves (23%; n = 14), and taking public transportation (5%; n = 3). Eighty percent (n = 48) of the youths were old enough to drive, however, only 36% (n = 17) had driver’s licenses. Reasons why 18% did not have licenses included failing the driver’s test, anxiety, disability limitations, financial limitations, and medical reasons such as seizures.

Eighty-five percent (n = 51) of the youths reported they were completely independent in self care, and 15% (n = 9) said they needed assistance in morning or evening care. Identified caregivers were parents in all cases, with one also using a personal-care attendant. All participants were satisfied with this arrangement.

Participants identified a variety of leisure activities they enjoyed, such as watching television or videos (95%), listening to music (90%), spending time with friends (90%), and using a computer (87%). Other activities included hunting, singing, dancing, acting, cooking, socializing on the phone, shopping, bicycling, church activities, collecting baseball cards, puzzle books, studying, and going to clubs and bars. In general, the participants expressed satisfaction with opportunities for social and recreational activities (range of 65%–95%).

Health Status in Spina Bifida Index (Severity of Illness)

Seventy-two percent (n = 43) of youth reported having a lumbar-sacral-level lesion, (sub-score of 1), and 28% (n = 17) reported having a thoracic level lesion (score of 2) which was validated during the FIM assessment. Twenty-eight percent (n = 17) of the youths reported conditions typical for their congenital anomaly, and therefore stated they were primarily healthy. Seventy-two percent (n = 43) identified conditions of advanced pathology, and 32% (n = 19) reported having comorbid conditions. Twenty-three percent (n = 14) had both advanced pathology and comorbidity, while 8% (n = 5) had comorbidity alone (Table 2). The final rankings for the Health Status Score resulted in a range of scores from 1 to 6 and an overall mean score of 3.38, SD = 1.33 (Table 3).

Functional Status (FIM)

The individual FIM item means ranged from 4.61 to 7 (possible range 1–7), indicating that youth in the study had a moderately high functional status level. The lower item means were in areas of bowel control (x = 5.44), bladder sphincter control (x = 4.61), and ability to traverse 14 stairs independently (x = 5.98). The domains where the group scored the highest in functional independence were in the areas of self-care, and transfers, while the lowest scores for functional independence were in the area of sphincter control, primarily due to neurogenic incontinence issues rather than the physical ability to toilet oneself. The comprehension score of the communication domain was lower due to the high percent (62%) of youths who needed to wear eyeglasses. The mean of the total scores of the FIM 116.8 (SD = 7.07, range 90–126, and skewness of –2.59; Table 4). The negative skewness reflects that the majority of the FIM scores fell at the higher end of the scale, which indicated that the youth were fairly independent in functional status.

Health-Related Quality of Life

The 47 items were used as a total score for HRQOL and the individual items were analyzed for central tendencies. There were six items with means lower than 4, indicating lower HRQOL: (1) feelings of being “treated different,” (2) not “satisfied with their school program,” (3) not “able to participate in group activities,” (4) not “challenged through sports,” (5) not “able to have children in the future,” and (6) did not “have someone with spina bifida to look up to as a role model.” The item for which there was the least agreement was whether the participant had considerable pain (mean = 1.53, SD = .77) indicating few participants acknowledged pain symptoms. The mean of total scores for HRQOL was 200.8 (SD = 19.54, range of 155–232, and skewness –0.43). The negative skewness reflects that the majority of the scores for HRQOL fell at the higher end of the scale, suggesting that the participants as a group were fairly positive about their quality of life.

Relationships Among the Variables

A Pearson correlation was performed on the variables of health status and functional status. Health status had a significant negative correlation with functional status (r = –0.32, p < .05), indicating that as participants reported problems with health; their functional status score or level of independence was lower. Neither health status (r = –0.14, p = .29) nor functional status (r = 0.07, p = 0.62) was correlated with HRQOL. A regression analysis was performed, with HRQOL entered as the criterion variable and functional status and health status entered simultaneously on step 1 in the regression equation (Table 5). The regression analysis, however, did not show significance (r2 = 0.02, df = 2, 57, p = 0.57). Based on these results, the combination of health status and functional status was not a good predictor of variance of HRQOL. This may be due to the statistically significant correlation between these two independent variables (r = –0.32, p < 0.05) indicating multicollinearity. In other words, this may be occurring because the instruments may be measuring the same attributes that would predict responses to questions about HRQOL.

Ancillary Data

There was a statistically significant, moderate, negative correlation between level of lesion and functional status (r = –0.42, p < .01): indicating that the youths with higher spinal cord lesions in the thoracic area had a decrease in functional independence, as would be anticipated. The participants were asked a global question on whether they felt that they had unresolved emotional needs, for example, feeling sad or depressed, that was coded as a dichotomous variable, emotional health issues. Of note is that one-third of the group, 33% (n = 20), reported having emotional issues that were unresolved. HRQOL (r = –0.48, p < 0.01) had a statistically significant correlation with emotional health issues, indicating that the youths who reported unresolved emotional issues also reported a lower HRQOL. To a global question regarding self-perceived health, 22% of the youths reported that they were in excellent health, 50% said they were in good health, and 30% said they had occasional or chronic health problems. None of the participants reported that they were in poor health. Thirty- two percent of the participants reported that they were currently experiencing health problems, which further supports the research on aging and health severity in youth by Lamenek, Jones, and Lieberman (2001). Self-perceived health correlated with their health status score (r = 0.42, p < 0.01), thus providing an indicator of validity for the Health Status in Spina Bifida Index (Leger, 2003). There was a trend for males in this study to report having more health problems, but this was not statistically significant. There was a statistically significant, positive correlation between age and self-perceived health (r = 0.29, p < 0.05), indicating that the older youths reported having more health problems. The participants’ self-perceived health had significant negative correlation with their self-perceived HRQOL (r = –0.29, p < 0.05), indicating that participants who reported health problems also reported a lower HRQOL. The correlation matrix of the main variables and ancillary data is reported in Table 6.

Discussion

In several ways, this study was both a pilot and feasibility study. Because of the lack of literature on the use of these measures with youths with spina bifida, a power analysis was not calculated for the sample size. Calculating one would be recommended for future studies. Although a continuous measure of health status and severity of illness was not attainable, there remains a need for further development and testing of a health status measure in spina bifida that includes primary, secondary, and comorbid conditions. This study supports earlier literature findings, as 80% of the sample had shunted hydrocephalus (Lazaretti & Pearson, 2004) and 60% had latex allergy, as compared with 73% reported by Meeropol (2001). This study begins to contribute to the literature by describing other potentially preventable conditions experienced by youth with spina bifida. The effect of these secondary conditions may impede function and quality of life as youths with spina bifida reach adulthood. One youth in this study reported that he had received a kidney transplant at age 21 after 5 years on renal dialysis. The additional effect of comorbid conditions also needs to be addressed. For example, there was one participant who reported having insulin-dependent diabetes mellitus, and another who reported having Tourette’s syndrome in addition to spina bifida. The ability to analyze the impact of the individual conditions on HRQOL was not undertaken in this study.

As noted earlier, the FIM for Children (WeeFIM) and FIM are being used in clinical arenas that provide care to patients with spina bifida. There is a need for clinicians to translate research findings to aid in developing practice standards. These research efforts can be used to assess the effects of therapies, assistive technology, pharmacological and surgical interventions, and educational and health programs. Rehabilitation nurses are uniquely trained in a comprehensive approach to care for people living with disabilities and thus are ideally suited to work as consultants, collaborators, and researchers in this effort. Rehabilitation centers have multidisciplinary teams that can provide comprehensive clinical approaches to care and can conduct long-term programs of clinical research with these patients. A new center at the Center for Disease Control and Prevention (2002) has a major life-span initiative devoted to living well with a disability and preventing secondary conditions. In this study, it was realized that youth with spina bifida report a high level of satisfaction with their HRQOL, are entering and succeeding at college life, are participating in recreation, sports activities, and other aspects of young adult living. Yet they are experiencing a number of secondary health conditions that leave them concerned for their futures.

Acknowledgments

The author thanks nursing colleagues in NEMA who added the content validity of the Health Status in Spina Bifida Index and aided in the recruitment of study participants. Thanks also to the NYU dissertation committee: Deborah Sherman, PhD RN; Elizabeth Ayello, PhD RN; and Mary Donohue, PhD OTRL. A special thank you is given to all the youth and their families who shred their stories and participated in this study.

About the Author

Robin R. Leger, PhD MS RN CCRP, is an assistant professor in the Department of Orthopaedic Surgery, GCRC # RR06192, of the University of Connecticut Health Center in Farmington, CT. Questions or comments about this article may be directed to Robin Leger, UCONN Health Center MARB room 0411, Farmington, CT, 06030-3805, or via e-mail to rleger@uchc.edu.

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