Objective: To what extent endogenous subclinical thyroid disorders contribute to impaired physical and cognitive function, depression, and mortality in older individuals remains a matter of debate.Design: A population-based, prospective cohort of the Longitudinal Aging Study Amsterdam.Methods: TSH and, if necessary, thyroxine and triiodothyronine levels were measured in individuals aged 65 years or older. Participants were classified according to clinical categories of thyroid function. Participants with overt thyroid disease or use of thyroid medication were excluded, leaving 1219 participants for analyses. Outcome measures were physical and cognitive function, depressive symptoms (cross-sectional), and mortality (longitudinal)Results: Sixty-four (5.3%) individuals had subclinical hypothyroidism and 34 (2.8%) individuals had subclinical hyperthyroidism. Compared with euthyroidism (n=1121), subclinical hypo-, and hyper-thyroidism were not significantly associated with impairment of physical or cognitive function, or depression. On the contrary, participants with subclinical hypothyroidism did less often report more than one activity limitation (odds ratio 0.44, 95% confidence interval (CI) 0.22–0.86). After a median follow-up of 10.7 years, 601 participants were deceased. Subclinical hypo- and hyper-thyroidism were not associated with increased overall mortality risk (hazard ratio 0.89, 95% CI 0.59–1.35 and 0.69, 95% CI 0.40–1.20 respectively).Conclusions: This study does not support disadvantageous effects of subclinical thyroid disorders on physical or cognitive function, depression, or mortality in an older population.

We now have the ability to measure a number of different vitamin D metabolites with very accurate methods. The most abundant vitamin D metabolite, 25-hydroxyvitamin D, is currently the best marker for overall vitamin D status and is therefore most commonly measured in clinical medicine. The added value of measuring metabolites beyond 25-hydroxyvitamin D, like 1,25-, and 24,25-dihydroxyvitamin D is not broadly appreciated. Yet, in some more complicated cases, these metabolites may provide just the information needed for a legitimate diagnosis. The problem at present, is knowing when to measure, what to measure and how to measure. For 25-hydroxyvitamin D, the most frequently used automated immunoassays do not meet the requirements of today’s standards for certain patient groups and liquid chromatography-tandem mass spectrometry is the desired method of choice in these individuals. The less frequently measured 1,25-dihydroxyvitamin D metabolite enables us to identify a number of conditions, including 1α-hydroxylase deficiency, hereditary vitamin D-resistant rickets and a number of granulomatous diseases or lymphoproliferative diseases accompanied by hypercalcaemia. Furthermore, it discriminates between the FGF23-mediated and non-FGF23-mediated hypophosphatemic syndromes. The 24,25-dihydroxyvitamin D metabolite has proven its value in the diagnosis of idiopathic infantile hypercalcaemia and has the potential of having value in identifying other diseases. For both metabolites, the understanding of the origin of differences between assays is limited and requires further attention. Nonetheless, in every way, appropriate measurement of vitamin D metabolism in the clinical laboratory hinges eminently on the comprehension of the value of the different metabolites, and the importance of the choice of method.

Early renal dysfunction is associated with a 38% increased fracture risk in individuals aged 65 years and older. In men but not women, early renal dysfunction is associated with decreased femoral neck bone mineral density (BMD) which can be partially explained by increased parathyroid hormone (PTH) concentrations.

Context: Central adiposity is associated with cardiovascular risk independently of total adiposity. Microvascular dysfunction is thought to contribute to obesity-associated insulin resistance and hypertension and may thus link central adiposity with cardiovascular risk. Objective: Our objective was to investigate how body fat distribution relates to microvascular function and the role of adipocytokines in these relationships. Design, Setting, and Participants: We cross-sectionally studied 51 healthy adults and 29 of their prepubertal children born at the VU University Medical Center in Amsterdam. Main Outcome Measures: We measured visceral and abdominal sc adiposity with magnetic resonance imaging and truncal and peripheral sc adiposity with skinfold thickness. Postocclusive skin capillary recruitment was assessed with videomicroscopy. Concentrations of C-reactive protein, IL-6, and TNF-α were combined in an inflammation score. Results: In adults, visceral adipose tissue and trunk/extremity skinfold ratio were inversely associated with capillary recruitment (partial correlation coefficients, −0.32, P = 0.03, and −0.37, P < 0.01, respectively). The inflammation score was inversely associated with capillary recruitment (r = −0.50; P < 0.01) and statistically explained 41% of the association between visceral adipose tissue and capillary recruitment. In children, trunk/extremity skinfold ratio was inversely associated with capillary recruitment (r = −0.49; P = 0.01), but other measures of adiposity were not. Conclusion: Our data in adults suggest a role for visceral adiposity and its associated proinflammatory state in capillary dysfunction and its possible sequelae such as hypertension and insulin resistance. Also, our findings in children and adults suggest that truncal sc adiposity is detrimental for capillary perfusion and that this process may start before puberty.