Somatic comorbidity of epilepsy in the general population in Canada.

PURPOSE: There is a notion that people with epilepsy have substantial and often unrecognized comorbidity of chronic conditions. However, most studies focus on selected patient groups; population-based studies are scarce. We compared the prevalence of chronic somatic conditions in people with epilepsy with that in the general population using Canadian, nationwide, population-based health data. METHOD: We examined epilepsy-specific and general population health data obtained through two previously validated, independently performed, door-to-door Canadian health surveys, the National Population Health Survey (NPHS, N = 49,000) and the Community Health Survey (CHS, N = 130882), which represent 98% of the Canadian population. The prevalence of epilepsy and 19 other chronic conditions was ascertained through direct inquiry from respondents about physician-diagnosed illnesses. Weighted prevalence, prevalence ratios (PR), and 95% confidence intervals were obtained for the entire population and for males and females separately. Multivariate analyses assessed the strength of association of comorbid conditions with epilepsy as compared with the general population. RESULTS: People with epilepsy had a statistically significant higher prevalence of most chronic conditions than the general population. Conditions with particularly high prevalence in epilepsy (prevalence ratio > or = 2.0) include stomach/intestinal ulcers (PR, CHS 2.5, NPHS 2.7), stroke (PR, CHS 3.9, NPHS 4.7), urinary incontinence (PR, CHS 3.2, NPHS 4.4), bowel disorders (PR, CHS 2.0, NPHS 3.3), migraine (PR, CHS 2.0, NPHS 2.6), Alzheimer's disease (PR, NPHS 4.3), and chronic fatigue (PR, CHS 4.1). There were no gender-specific differences in prevalence of chronic conditions among people with epilepsy. CONCLUSIONS: People with epilepsy in the general population, not only those actively seeking medical care, have a high prevalence of chronic somatic comorbid conditions. The findings are consistent across two independent surveys, which show that people with epilepsy in the general population have a two- to five-fold risk of somatic comorbid conditions, as compared with people without epilepsy. This patient-centered comorbidity profile reflects health aspects that are important to people with epilepsy, and indicate the need for a more integrated approach to people with epilepsy. The impact of epilepsy relative to other comorbid conditions requires further analysis, as does the contribution of comorbidity to epilepsy intractability and to differential health care needs. Similarly, it remains to be determined whether the observed comorbidity patterns are specific to epilepsy or simply reflect a pattern that is common to chronic illnesses in general.

National and regional prevalence of self-reported epilepsy in Canada.

PURPOSE: To assess the point prevalence of self-described epilepsy in the general population nationally, provincially, and in different groups of interest. METHODS: We analyzed data from two national health surveys, the National Population Health Survey (NPHS, N=49,000) and the Community Health Survey (CHS, N=130,882). Both surveys captured sociodemographic information, as well as age, sex, education, ethnicity, household income, and labor force status of participants. Epilepsy was ascertained with only one question in both surveys. "Do you have epilepsy diagnosed by a health professional?" (NPHS) and "Do you have epilepsy?" (CHS). Prevalences were age-adjusted by using national standard populations at the time of each survey. Exact 95% confidence intervals were obtained. RESULTS: In the NPHS, 241 of 49,026 subjects described themselves as having been diagnosed with epilepsy, yielding a weighted point prevalence of 5.2 per 1,000 [95% confidence interval (CI), 4.9-5.4]. In the CHS, 835 of 130,822 subjects described themselves as having epilepsy, yielding a weighted point prevalence of 5.6 per 1,000 (95% CI, 5.1-6.0). Trends in differences in prevalence among some Canadian provinces were observed. Prevalence was statistically significantly higher in groups with the lowest educational level, lowest income, and in those unemployed in the previous year. Prevalence also was higher in nonimmigrants than in immigrants. CONCLUSIONS: The overall and group-specific results are in keeping with those obtained in other developed countries by using different ascertainment methods. We discuss methodologic aspects related to the ascertainment of epilepsy in both surveys, and to the validity and implications of our findings.

Comparative responsiveness of generic and specific quality-of-life instruments.

We assessed the relative responsiveness of generic and specific quality of life instruments in 43 randomized controlled trials that compared head-to-head 31 generic and 84 specific instruments. Using weighted effect size as the metric of responsiveness, we assessed the impact of instrument type, disease category, and magnitude of underlying therapeutic effect on responsiveness, and assessed the responsiveness of specific instruments relative to the corresponding domains of generic measures. In studies with a nonzero therapeutic effect, specific instruments (mean = 0.57) were significantly more responsive than generic instruments (mean = 0.39, P =.01), and than the corresponding domains of generic instruments (mean = 0.40, P =.03). Studies with low, medium, and high therapeutic effects showed a corresponding gradation in responsiveness differences between specific and generic instruments. We conclude that, overall, specific instruments are more responsive than generic tools, and that investigators may come to misleading conclusions about relative instrument responsiveness if they include studies in which the magnitude of the underlying therapeutic effect is zero.

An epilepsy questionnaire study of knowledge and attitudes in Canadian college students.

PURPOSE: Controversy exists about the relation of societal knowledge and attitudes regarding epilepsy. We conducted a survey to examine knowledge and attitudes, to note gender and occupational influences, and to examine the effect of an informational brochure. METHODS: We administered a standardized questionnaire that noted demographics and examined knowledge and attitudes regarding epilepsy and persons with epilepsy, respectively, to a wide variety of Canadian college students. In a separate class we gave every other student a brochure regarding epilepsy and then administered the questionnaire to both the naïve and brochure-exposed students. RESULTS: Knowledge was patchy and weakest for the approximate prevalence of epilepsy in the population, hereditary epilepsy and several other etiologies, recognition of nonconvulsive seizures as a type of epilepsy, and knowledge of antiepileptic drug-induced teratogenicity. In contrast, attitudes were more uniformly favorable. However, 11 and 14%, respectively, showed negative bias against persons with epilepsy having children and equal opportunity for occupational employment. Women were slightly but significantly more tolerant than men. The brochure-exposed group showed better knowledge but equivalent attitudes compared with the naïve group. CONCLUSIONS: Results compare favorably with surveys in other countries. Although knowledge was patchy, it could be easily improved on with an educational brochure. Attitudes were positive but show some discrepancies from knowledge and a gender effect.