A total of 153 individuals with spina bifida aged 12 to 31 years participated in the face-to-face interviews, a completion rate of 75% (10% refused the interview, 8% were unreachable, 5% had severe cognitive limitations²¹ and 2% were deceased). For the current study, we focused on 130 individuals (64 males, 66 females) who were 16 years or older and completed the supplemental questionnaire on substance abuse. To validate the population-based nature of our sample, we applied a previously estimated crude prevalence of spina bifida (3.07 per 10 000 population aged 0–19y; 95% CI 2.96–3.17)²² to the 2005 population of Arkansas aged 15 to 29 years (n=590 333). The expected number of people with spina bifida aged 15 to 29 years in 2005 was 181 (95% CI 174–187), which was comparable with the number in our overall sample plus non-respondents. The mean age of the participants was 23 years (SD 4y 5mo). The demographic characteristics and health-related conditions of participants are presented in Table I. The distributions of participants by these characteristics did not differ significantly among three age groups (16–19y, 20–24y, 25–31y), except for marital status, living arrangement, bowel incontinence and history of shunt surgery (p<0.05). There were no sex differences in the distributions of HRBs (data not shown).

Our study is the first population-based study to examine HRBs among young adults with spina bifida. We observed that a significant proportion of young adults with spina bifida have led unhealthy lifestyles and engaged in one or more risky behaviors. Alcohol abuse was positively associated with major depression. Depression and low self-rated health were highly prevalent. Compared with similar aged adults in the general population, young people with spina bifida tend to eat less healthy diets, do less exercise and engage more in sedentary activities. Also, young people with spina bifida were less likely to abuse tobacco, alcohol and illicit drugs, and when they did, it was at later ages. Nearly 90% of the study participants saw a doctor in the past year indicating a greater opportunity for screening and monitoring of mental health and HRBs. Webb²³ has pointed out that the general healthcare needs of adults with spina bifida (including health risk screening and counseling) are sometimes overlooked because so much emphasis is placed on spina bifida specific care.

That significant proportions of respondents were not engaged in any form of regular physical activity and spend time in sedentary activity may indicate challenges being encountered by young people with spina bifida for access to physical and leisure activities. These challenges may include the lack of facilities adaptive for physical activities of the spina bifida population, transportation issues accessing available facilities and difficulties obtaining personal assistance to engage in these activities.^11,24 Attitudinal and motivational factors²⁵ and medical contraindications may also play a role in the lack of physical activity. Our observation of poor dietary habits among respondents is consistent with a Canadian study of adolescents with physical disabilities that reported a lower likelihood of eating fresh produce but a higher likelihood of eating high-fat foods in comparison with a national sample.¹¹ Poor dietary habits and low levels of regular physical activity may partly explain high prevalence of being overweight reported by respondents. These observations are important because limited physical activity and poor dietary habits, which cause obesity, are modifiable and obesity can be reduced, if not entirely prevented.²⁶ Part of good childcare should include early efforts with family engagement to encourage physical activity and healthy eating to prevent obesity in this population.

The observation of overall and age-specific prevalence of substance abuse among respondents which was lower than national estimates¹⁹ is in agreement with other studies.^11,12 The low level of engagement of smoking, alcohol and illicit drugs among individuals with spina bifida may be partially explained by the high level of parental/family supervision in their social activities²⁷ and/or lack of opportunity resulting from mobility and financial constraints on exposure to the social environment that could potentially influence negative behaviors.^11,12 Although the prevalence of substance abuse among individuals with spina bifida may be low, that participants with major depression were more likely to drink alcohol is a cause for concern because it can lead to worsening of adverse health and social outcomes. Previous studies among young people in the general population have shown that substance use and risky sexual behaviors are often associated with anxiety and depressive disorders.^8,9 As nearly half of young respondents were experiencing depression comparable with other clinic- or community-based studies,^10,28 screening and counseling on both mental health disorders and substance abuse should be a priority for healthcare providers in both primary and specialty care settings.

It is noteworthy that the mode of substance abuse was highest among individuals with spina bifida in their late 20s, though only illegal drug abuse and alcohol drinking showed significant positive trends possibly because of the limited sample size. By contrast, the risk profile among the general population shows a peak in the early 20s.⁷ Young individuals with spina bifida may be experiencing an especially prolonged transition to adult roles and responsibilities with diminished parental supervision and the weakening of the safety net that normally supports adolescents and younger children such as school and quality healthcare, which are important contextual factors associated with unhealthy living and risky behaviors.⁷ Though adolescents with spina bifida are capable of high levels of independent functioning across multiple domains, they are at risk of delays in development of self-management and independence,²⁹ and are therefore less likely to move into marriage, parenthood and employment at the same rates or age as typical young adults. This was reflected in our study where the majority of respondents in their late 20s was not employed (69%), remained unmarried (88%) and still lived with families for their assistance (43%).

Overall delays in social maturation and independence and the lack of traditional supportive systems may explain the late onset of substance abuse among young adults with spina bifida. As with the general population,^8,9 the presence of poor health and depression also add to the risk of substance abuse. The loss of the traditional supports of education and child-specific healthcare,⁷ plus the ambivalence of being dependent on family,³⁰ puts the young adult with spina bifida in a vulnerable position. Feeling less powerful in mastering one’s life and feeling less healthy may magnify depression and threaten the development of independence and self-management of health. Health status is already compromised and slowly starts to decline (data not shown) with accumulation of physical symptoms over time. This may lead to a fatalistic life view⁵ which could be reflected in unhealthy behaviors such as tobacco, drug and alcohol abuse among respondents in their late 20s. Declining health status may also decrease motivation to seek out intimate relationships like marriage. This health status, along with loss of public insurance, transportation challenges and depressive symptoms, may also limit the pursuit of regular employment. To counteract these trends, interventions such as peer support, group counseling and specific skills training may be necessary to help young adults with spina bifida to maintain a more positive and hopeful outlook. Ongoing healthcare is also needed to monitor for specific organ-system progression (e.g. renal function, shoulder girdle overuse).

The strength of our study is that it is based on a statewide population with spina bifida rather than a clinic sample and that it has valuable information to examine unhealthy lifestyles among young adults with spina bifida in their late teens and 20s. However, it has certain limitations. First, the study was cross-sectional and causality could not be assessed. Second, since the ASCC state-based registry is service-oriented, there may be individuals who remained unregistered, although we believe most young people with spina bifida were captured by the system, based on our calculation of the expected number of individuals with spina bifida in Arkansas. Even among those registered, 25% did not complete the interview for a number of reasons. Third, a direct comparison group of healthy peers was not feasible because the sample was obtained from a spinal cord disability registry. Fourth, in addition to recall bias, self-reporting of conditions may change over time because of the maturity of those reporting, e.g. 28-year-olds may report their weight more accurately or honestly than 17-year-olds. Fifth, the sensitive nature of questions such as illicit drug abuse may underestimate usage. Sixth, due to survey exclusion criteria, the results may not be generalizable to those with spina bifida who have a severe cognitive limitation. Lastly, since this supplementary study on HRBs was part of a large survey, only a limited number of questions on HRBs were asked. For example, a distinction between experimental versus habitual abuse of substances was not made. A larger population-based study more focused on HRBs and predisposing psychosocial and environmental factors, could answer these additional questions.

In summary, a notable proportion of young individuals with spina bifida exhibit unhealthy behaviors that continue into their late 20s. To promote healthy behaviors and quality of life in this population, it is necessary to increase awareness of their health risk profile among people with spina bifida and their caregivers. Although substance use is less common than expected for their age among young people with spina bifida, the presence of low self-rated health, depression and its relationship with certain HRBs warrants continued monitoring of physical and mental health by healthcare providers. Discussions should also begin during childhood with a focus on helping the child work toward mastering a fully independent life such as educational and vocational achievement, independent living, healthy lifestyle choices and social participation. Finally, promoting access to accommodative social support and preventive services would increase the chances of successful adult living for individuals with spina bifida.