Osteoprotective Knowledge in a Multiethnic Epilepsy Population

John O. Elliott, MPH; Brenda F. Seals, PhD, MPH; Mercedes P. Jacobson, MD


J Neurosci Nurs. 2008;40(1):14-24. 

In This Article



This study examined an adult epilepsy population with a mean age of 45 years (SD = 12.9, range 19 to 78 years); 28 (30%) were male and 66 (70%) female. Males were underrepresented based on a demographic analysis of inpatient and outpatient contacts for 2002–2004, where 54% of patients being seen for seizures or epilepsy were male and 46% were female. Participants included both young and old people and those newly diagnosed with epilepsy. Age and yearly income were recoded into three groups for analysis, and number of years of education was recoded into two groups. Fifty participants were Caucasian, 32 were African American, and 12 were Latino. The average length of AED exposure was 20 years (SD = 13.9, range 1 to 50). Forty-one participants (44%) reported taking a calcium supplement. Demographic variables are summarized in Table 2 .

Osteoporosis Knowledge

A one-way analysis of variance (ANOVA) of the subscales for the OKT was performed based on various demographic factors ( Table 3 ). Ethnicity was recoded as Caucasian or non-Caucasian for this analysis. No significant differences related to age or gender for either exercise or calcium knowledge were found. One-way ANOVA of ethnicity found non-Caucasians had much lower knowledge for calcium (F = 8.15, p = .005) and exercise (F = 7.71, p = .007). Participants reporting more than 12 years of education had higher knowledge scores for calcium (F = 39.25, p = .000) and exercise (F = 17.09, p = .000). Participants reporting an income above $30,000 had higher levels of knowledge for calcium (F = 3.93, p = .024) and exercise (F = 3.46, p = .037).

Participants who were seizure-free for longer than 1 year also had higher knowledge related to calcium (F = 6.76, p = .002) and exercise (F = 3.59, p = .032) compared to those reporting seizures within the past year. Significant differences in calcium knowledge were noted for individuals previously diagnosed with bone loss (F = 4.98, p = .028). In addition, for those reporting a family history of osteoporosis, knowledge was higher for calcium (F = 5.58, p = .005) and exercise (F = 6.23, p = .003). Participants taking calcium supplements had higher knowledge for calcium (F = 5.35, p = .023) but not for exercise. No significant differences were found related to fracture history.

OKT Results in Previous Studies

Table 4 displays the results of previous studies using the OKT in various populations as a means of comparison. The descriptive statistics for the current study found mean (standard deviation) scores of 7.16 (3.39) for the OKT exercise subscale, 8 (3.68) for the OKT calcium subscale, and 11.71 (4.92) for the total score. The mean OKT total score corresponds to a correct response rate of 48.8%. The mean scores displayed in Table 4 are significantly lower than those for all but two of the previous studies in nonepilepsy participants (N = 790).

Bivariate Pearson Correlation Analysis

Pearson correlations were performed to determine the relationship between the osteoporosis knowledge subscales and various demographic and clinical factors. Ethnicity was negatively correlated with both exercise (r = –.28, p = .007) and calcium (r = –.29, p = .005) knowledge. Education was positively correlated with exercise (r = .40, p = .000) and calcium (r = .55, p = .000) knowledge. Yearly income was also positively correlated with exercise (r = .28, p = .017) and calcium (r = .28, p = .015) knowledge. A diagnosis of bone loss (r = .23, p = .028) and calcium supplement use (r = .23, p = .023) were also positively correlated with calcium knowledge.

Knowledge by Ethnicity

Although education and income were more strongly correlated with knowledge than was ethnicity, the following discussion focuses on ethnicity because the ultimate goal is to tailor clinic educational messages, and it is recommended that such customization efforts focus on cultural differences. Therefore, we chose to do analyses using two-tailed independent Student's t tests to review correct answers on the OKT in relation to ethnicity (coded as Caucasian and non-Caucasian; see Table 1 ). For all but two knowledge questions (numbers 10 and 20), fewer non-Caucasians answered correctly. More Caucasians (66%) than non-Caucasians (45%) answered question 1 correctly, namely, that eating a diet low in milk products is a risk factor for osteoporosis (t = 2.03, p = .046). For question 2, regarding whether a woman in menopause is at greater risk, 64% of Caucasians answered correctly versus only 17% of the non-Caucasians (t = 2.51, p = .014). More Caucasians (68%) than non-Caucasians (48%) correctly identified, on question 5, that having a grandmother or mother with osteoporosis is a risk factor (t = 2.01, p = .047).

For question 9, knowledge of exercise as a protective factor, 74% of Caucasians versus only 43% of non-Caucasians answered correctly (t = 3.17, p = .002). For question 11, only 14% of non-Caucasians versus 29% of Caucasians identified bicycling as a more protective form of exercise compared to yoga or housecleaning (t = 2.61, p = .011). For question 22, significantly more Caucasians (42%) versus non-Caucasians (11%) correctly identified 800 mg or more a day as the recommended amount of daily calcium (t = 3.49, p = .001). For question 24, more Caucasians (74%) identified the best reason for taking a calcium supplement ("If a person does not get enough calcium from the diet") compared to non-Caucasians (52%), based on the Student's t test (t = 2.22, p = .029).

Overall Knowledge Deficiencies

In the identification of risk factors, few participants in either group recognized that having "big bones" was protective (question 3) or that white women (question 6) and women who have who have had their ovaries removed (question 7) are at an increased risk for osteoporosis. Exercise knowledge, overall, was low in both groups. Deficiencies are apparent in identifying exercises that are weight bearing (questions 10–16), such as walking, bicycling, and aerobic dancing, as well as the appropriate length and intensity of exercise. Overall, participants performed fairly well in identifying foods high in calcium, with the exception of question 18, "Which of these is a good source of calcium: watermelon, corn, or canned sardines": less than 25% identified sardines as the correct answer. Also, few individuals were aware of the recommended daily amounts of calcium (>800 mg) or how many glasses of milk an adult must drink to meet the recommended amount of calcium (two or more glasses daily).