Previous studies have identified many biomarkers that are associated with aging and related outcomes, but the relevance of these markers for underlying processes and their relationship to hypothesized systemic dysregulation is not clear. We address this gap by presenting a novel method for measuring dysregulation via the joint distribution of multiple biomarkers and assessing associations of dysregulation with age and mortality. Using longitudinal data from the Women's Health and Aging Study, we selected a 14-marker subset from 63 blood measures: those that diverged from the baseline population mean with age. For the 14 markers and all combinatorial sub-subsets we calculated a multivariate distance called the Mahalanobis distance (MHBD)2 for all observations, indicating how “strange” each individual's biomarker profile was relative to the baseline population mean. In most models, MHBD correlated positively with age, MHBD increased within individuals over time, and higher MHBD predicted higher risk of subsequent mortality. Predictive power increased as more variables were incorporated into the calculation of MHBD. Biomarkers from multiple systems were implicated. These results support hypotheses of simultaneous dysregulation in multiple systems and confirm the need for longitudinal, multivariate approaches to understanding biomarkers in aging.

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Background Long-term survivors of pediatric cancer are at risk for life-threatening late effects of their cancer. Previous studies have shown excesses in long-term mortality within high-risk groups defined by demographic and treatment characteristics. Methods To investigate conditional survival in a pediatric cancer population, we performed an analysis of conditional survival in the original Childhood Cancer Survivor Study (CCSS) cohort and the Surveillance, Epidemiology and End Results (SEER) database registry. The overall probability of death for patients in 5 years and 10 years after they survived 5, 10, 15, and 20 years since cancer diagnosis, and cause-specific death in 10 years for 5-year survivors were estimated using the cumulative incidence method. Results Among CCSS and SEER patients who were alive 5 years post cancer diagnosis, within each diagnosis group at least 92% are alive in the subsequent 5 years, except leukemia patients of whom only 88% of 5-year survivors remain alive in the subsequent 5 years. The probability of all-cause mortality in the next 10 years on patients who survived at least 5 years after diagnosis, was 8.8% in CCSS and 10.6% in SEER, approximately three quarter of which were due to neoplasms as causes of death. Conclusion The risk of death of pediatric cancer survivors in 10 years can vary between diagnosis groups by at most 12% even up to 20 years post diagnosis. This information is clinically important in counseling patients on their conditional survival, particularly when survivors are seen in long-term follow-up.

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SYNOPSIS A very rapid method of agar gel electrophoresis on glass slides, together with a superior visualization technique employing simultaneous coupling of a hydrolysed naphthol substrate, have been developed for the identification of the tissues of origin of serum alkaline phosphatase. Combined with L-phenylalanine inhibition, specific for the intestinal enzyme, and heat inactivation, specific for the placental enzyme, the heterogeneity of serum alkaline phosphatase has been demonstrated. Normal adult serum contains predominantly liver-type alkaline phosphatase with a small but variable quantity of intestinal enzyme, and little or no bone enzyme.In childhood and in infancy there is in addition a bone isoenzyme present, the amount gradually falling to adult levels with age. In pregnancy, the rise in serum alkaline phosphatase is due to the placental enzyme.A study of nearly 2,000 sera has been undertaken and it is found that the bone enzyme is increased in osteoblastic bone diseases while in hepato-biliary disorders there is an increase in liver type enzyme. The main theories explaining the rise in serum alkaline phosphatase are examined.The origin of serum alkaline phosphatase has interested many workers ever since Kay (1929) and Roberts (1930) first demonstrated that increased serum activity was found in certain bone and hepatobiliary disorders. The problem of the origin of the enzyme is intricately bound up with that of the mechanisms by which the serum activity is increased or decreased in health and in disease. It has long been realized that serum alkaline phosphatase arises from tissues rich in the enzyme (Kay, 1932). Previous attempts at identification of the tissues of origin were handicapped not only by lack of direct methods, but also by the influence of the work of Robison and his associates linking alkaline phosphatase with calcification (