Convergence insufficiency in patients with post-concussion syndrome is accompanied by a higher symptom load: a cross-sectional study.

OBJECTIVE: To estimate the prevalence of convergence insufficiency (CI) in adult patients with post-concussion syndrome and determine the impact of CI on symptom load. METHODS: Cross-sectional study of 103 patients with neurological symptoms 2-6 months after a concussion. Symptoms were assessed with the Rivermead Post Concussion Symptoms Questionnaire (RPQ), and CI was diagnosed using near point of convergence, vergence facility, and the Convergence Insufficiency Symptom Survey. The RPQ score for patients with and without CI was compared, and sensitivity, specificity, and area under the receiver operating characteristic curve for the two visually related RPQ questions as indicators of CI were calculated. RESULTS: The proportion of patients diagnosed with symptomatic CI was 20.4% (95% confidence interval: 13.1-29.5%). The RPQ score was significantly higher for patients with symptomatic CI both before (p = .01) and after removal of the two visually related questions in the RPQ-questionnaire (p = .03). The two visually related RPQ questions were unable to detect CI. CONCLUSION: In patients with post-concussion syndrome, the load of nonvisual symptoms is higher in the presence of CI. A prospective interventional study on CI is required to study the relationship between CI and other post-concussion symptoms.

Accidental deaths among persons with schizophrenia: A nationwide population-based cohort study.

OBJECTIVES: Persons with schizophrenia have a shorter life expectancy by 15-20years compared to the background population, but little is known about deaths caused by accidents. We aimed to investigate the rates of accidental death among persons with schizophrenia and compare these rates with those of the background population. METHODS: We conducted a national register-based cohort study of all persons born in Denmark between 1955 and 2011. The cohort included 2,703,307 persons, representing 56,845,085 person years at risk. We compared rates of accidental death between persons with schizophrenia and those without by using Cox regression analysis. The main outcome measure was hazard ratio (HR) for accidental death. RESULTS: A total of 12,425 accidental deaths were identified, including 371 accidental deaths among persons with schizophrenia. We found an increased HR for both women with schizophrenia (10.47; 95% CI=8.07-13.58) and men with schizophrenia (8.33; 95% CI=7.44-9.33) compared to the background population. After adjusting for substance abuse, we found attenuated HRs for both women (HR=3.22; 95% CI=2.46-4.20) and men (HR=3.23; 95% CI=2.87-3.63). CONCLUSIONS: Schizophrenia is a strong independent risk factor for accidental deaths. Substance abuse seems to constitute a substantial part of the association.