Background: Incidence studies of spinal cord injury (SCI) are important for health-care planning and epidemiological research. This review gives a quantitative update on SCI epidemiology worldwide through a statistical evaluation of incidence rates. Methods: A systematic review was conducted. For each study, the crude rate ratio was calculated and, when possible, age- and gender-adjusted incidence rate ratios with 95% CI were determined by direct adjustment or using Poisson regression. Results: Thirteen studies were included. Annual crude incidence rates in traumatic SCI varied from 12.1 per million in The Netherlands to 57.8 per million in Portugal. Compared to the Portuguese reference study, incidence rates showed a 3-fold variation, with the highest rates in Canada and Portugal. Most traumatic SCI studies showed a bimodal age distribution. The first peak was found in young adults between 15 and 29 years and a second peak in older adults (mostly ≧65 years). Motor vehicle accidents and falls were the most prevalent causes of injury accounting for nearly equal percentages. In contrast, another age pattern in non-traumatic SCI reflected steadily increasing incidence with advancing age. Conclusions: The results show significant variation in SCI incidence with changing epidemiological patterns. A trend towards increased incidence in the elderly was observed, likely due to falls and non-traumatic injury.

Background: Epidemiologic evidence of surgical transmission of sporadic Creutzfeldt-Jakob disease (sCJD) remains controversial. Methods: From Danish and Swedish registries we selected 167 definite and probable sCJD cases (with onset between 1987 and 2003) and 3,059 controls (835 age-, sex-, and residence-matched, and 2,224 unmatched). Independent of case/control status, surgical histories were obtained from National Hospital Discharge Registries. Surgical procedures were categorized by body system group and lag time to onset of sCJD. Exposure frequencies were compared using logistic regression. Results: A history of any major surgery, conducted ≧20 years before sCJD onset, was more common in cases than both matched (OR = 2.44, 95% CI = 1.46–4.07) and unmatched controls (OR = 2.25, 95% CI = 1.48–3.44). This observation was corroborated by a linear increase in risk per surgical discharge (OR = 1.57, 95% CI = 1.13–2.18; OR = 1.50, 95% CI = 1.18–1.91). Surgery of various body systems, including peripheral vessels, digestive system and spleen, and female genital organs, was significantly associated with increased sCJD risk. Conclusions: A variety of major surgical procedures constitute a risk factor for sCJD following an incubation period of many years. A considerable number of sCJD cases may originate from health care-related accidental transmission.

Spinal cord injury (SCI) leading to neurological deficits produces long-term effects that persist over a lifetime. Survival analysis of patients with SCI, at individual and population level, is important for public health management and the assessment of treatment achievements. The current study evaluated survival following traumatic and non-traumatic SCI worldwide. A systematic review was conducted, and all included papers were assessed for quality using a purposely designed assessment form. Survival data were presented in Kaplan-Meier curves and compared using the log-rank test. Sixteen studies were included of which 11 concerned traumatic SCI, four non-traumatic SCI, and one both. Crude standard mortality rates (SMRs) revealed that overall mortality in SCI is up to three times higher than in the general population. Survival rates were statistically significantly lower in non-traumatic SCI than in traumatic SCI (log-rank p = 0.000). Age at injury, neurological level, extent of lesion, and year of injury have been described as predictors of survival. Causes of death stem from secondary complications, with failure of the respiratory system being the leading cause. This is the first systematic literature review on survival analysis following SCI worldwide. An increase in survival over time was found. However, the SMRs of individuals with SCI still exceed those of an age-matched non-disabled population, mainly due to secondary complications. Lower survival rates were observed in non-traumatic SCI compared with traumatic SCI.