Gerontology

<b><i>Background:</i></b> In the last decade, an increasing body of empirical evidence has gathered to establish an association between higher cognitive ability in youth and later mortality, less morbidity and better health. This field of research is known as cognitive epidemiology. The causes of these associations are not understood. <b><i>Objective:</i></b> Among the possible explanations for the associations is the suggestion that they might, in part, be accounted for by general bodily ‘system integrity’. That is, scoring well on cognitive ability tests might be an indicator of a more general tendency for complex systems in the body to be efficient. The construct of system integrity is critically assessed. <b><i>Method:</i></b> This viewpoint provides a critical presentation and an empirical and theoretical evaluation of the construct of system integrity as it is used in cognitive epidemiology. <b><i>Results:</i></b> A precedent of the system integrity suggestion is discovered. The empirical tests of the system integrity idea to date are critically evaluated. Other possible routes to testing system integrity are suggested. There is a critical re-evaluation of the idea and other, related concepts. <b><i>Conclusion:</i></b> The construct of system integrity is distinct from related constructs. It is still underdeveloped theoretically, and undertested empirically within cognitive epidemiology.

The Atherosclerosis Risk in Communities Study administered cognitive function tests to more than 14,000 middle-aged adults in 1990–1992. The battery included the Delayed Word Recall test, the Digit Symbol Subtest of the Wechsler Adult Intelligence Scale-Revised, and the Controlled Oral Word Association (Word Fluency) test. Test performance was correlated positively with education level, negatively with age, was better in women than in men, and better in managers/professionals compared with other occupations. After controlling for these factors, race and community, the findings most consistent for both sexes were that Delayed Word Recall was negatively associated with depressive symptoms, diabetes, and fibrinogen level; the Digit Symbol Subtest was associated with marital status, negatively associated with depressive symptoms, smoking status, fibrinogen level, and carotid intima-media thickness, and positively associated with alcohol drinking and FEV₁; and the Word Fluency test was positively associated with marital status, alcohol drinking, sports participation, and FEV₁. Most of these cross-sectional results were in the predicted direction and have biologic plausibility, but mean differences between extreme categories were small (generally on the order of 0.1 to 0.2 of a standard deviation). Longitudinal study is warranted to evaluate whether small differences in middle-age lead to larger, clinically meaningful deficits with aging.

<i>Background:</i> Acute myocardial infarction (AMI) in elderly patients is often unrecognized and associated with poor prognosis. <i>Objectives:</i> To investigate management and efficacy of reperfusion therapy to the elderly patients with AMI. <i>Methods: </i>From the January 1, 2001 to October 31, 2002, 964 patients with AMI were included in the French regional RICO survey. The patients were divided into three groups: younger (<70 years old), elderly (70–79 years old) and very elderly (≧80 years old). <i>Results:</i> Distribution of groups was 56, 27, and 16%, respectively. The longest time delay to first request for medical attention was found in the very elderly group (30 and 55 vs. 90 min, respectively, p < 0.05). Rate of lysis fell significantly with increasing age (35, 22 and 9%, respectively, p < 0.001) but the time delay to lysis was similar for the 3 groups. The proportion of patients who benefited from primary percutaneaous transluminal coronary angioplasty decreased with age (21, 15, 11%, respectively, p < 0.001), but time delay to balloon angioplasty was similar and no difference in mortality rate was observed between the three groups after reperfusion. The incidence of in-hospital cardiovascular events (cardiogenic shock and recurrent myocardial infarction/ischemia) and in-hospital mortality increased with age (5, 13, 17%, respectively, p < 0.001). Moreover, multivariate analysis showed that only ejection fraction and Killip >1 were independent predictive factors for in-hospital cardiovascular mortality, respectively (OR 5.15, 95% CI 2.08–12.74, p < 0.0001 and OR 3.81, 95% CI 1.90–7.65, p < 0.0001), whereas age, sex, diabetes and anterior location were not significant. <i>Conclusion:</i> Our data in an unselected population indicate that very elderly patients were characterized by increased pre-hospital delays and less frequent utilization of reperfusion therapy, although no difference in the mortality in reperfused patients could be observed between the three age groups.

Effect of ageing on insulinemia, determined by radio-immunological method, has been studied in male rats aged 3, 12 and During the intravenous hyperglycemia test, the coefficient of glucose assimilation decreases significantly with age, whereas a hype insulinemia is to be seen. This becomes apparent at the moment of the hyperglycemic peak and still persists 20 min after the beginning of the test. Senescence in the rat is, therefore, accompanied by early decrease in glucose tolerance and abnormally high IRI (immunoreactive insulin) level in the blood.

<i>Background:</i> With today’s 21st century technological advancements, it is expected that individuals will either retain their natural teeth or obtain functional tooth replacements throughout their entire life. Modern dental therapies for the replacement of missing teeth largely utilize partial or complete dentures and titanium implants capped with prosthetic crowns. Although these prostheses serve a purpose, they are not equivalent, neither in function nor aesthetics, to natural teeth. Recent progress in dental tissue engineering has lent significant credibility to the concept that biological replacement teeth therapies may soon be available to replace missing teeth. <i>Objective:</i> In this review, we summarize the emerging concepts of whole-tooth replacement strategies, using postnatal dental stem cells (DSCs) and dental tissue engineering approaches. <i>Methods:</i> We provide a thorough and extensive review of the literature. <i>Results:</i> Current approaches to achieve clinically relevant biological replacement tooth therapies rely on the cultivation of DSCs capable of relaying odontogenic induction signals, through dental epithelial-mesenchymal cell interactions. DSC expansion and differentiation can be achieved by programming progenitor stem cells to adopt dental lineages, using instructive, bioengineered scaffold materials. Periodontal ligament regeneration in particular has demonstrated significant progress recently, despite the somewhat unpredictable clinical outcomes, with regard to its capacity to augment conventional metallic dental implants and as an important component for whole-tooth tissue engineering. Following recent advances made in DSC and tissue engineering research, various research groups are in the midst of performing ‘proof of principle’ experiments for whole-tooth regeneration, with associated functional periodontal tissues. This mini-review focuses on recent and promising developments in the fields of pulp and periodontal tissue DSCs that are of particular relevance for dental tissue and whole-tooth regeneration. <i>Conclusion:</i> Continued advances in the derivation of useable DSC populations and optimally designed scaffold materials unequivocally support the feasibility of dental tissue and whole-tooth tissue engineering.

<b><i>Background:</i></b> The preservation of physical functions such as muscle strength, balance and mobility is fundamental to maintaining independence in activities of daily living (ADL). The physical activity level of most nursing home residents is very low, which implies that they are often subject to a decline in health, mobility, autonomy and social contacts and are also at risk of suffering a decline in mental well-being. In a previous study, we demonstrated that transfers, balance and physical activity level improved after 3 months of individually tailored intervention in nursing home residents. <b><i>Objective:</i></b> To evaluate the long-term effects on ADL, balance function, physical activity level, physical performance, falls-related self-efficacy, well-being and cognitive function 3 months after the completion of our intervention in nursing home residents. <b><i>Methods:</i></b> The study was a multicenter randomized, controlled clinical trial with a parallel-group design. It was conducted in nursing homes in Sweden, Norway and Denmark, with an intervention period lasting 3 months and a follow-up at 6 months. Initially, 322 nursing home residents with a mean age of 85 years were included; 85 from Sweden, 171 from Norway and 66 from Denmark. Of these, 241 [129 intervention group (IG), 112 control group (CG)] were eligible for the 6-month follow-up tests. The level of dependence in ADL, physical activity level, several dimensions of physical function, well-being, falls-related self-efficacy and cognitive function were assessed with reliable and valid instruments at baseline, immediately after 3 months of intervention and 3 months later at the 6-month follow-up. <b><i>Results:</i></b> After 3 months of intervention and an additional period of 3 months without intervention, only the following 2 variables demonstrated significant group differences: social and cognitive function, measured by the Functional Independence Measure n-r, where the IG deteriorated while the CG was almost stable. However, regarding transfers, the IG deteriorated significantly less than the CG. <b><i>Conclusion:</i></b> Without supervised physical exercise that challenged the individuals' capability, gains in ADL function, balance and transfer ability deteriorated during the 3 months following the intervention period. Thus, continuous, individually adjusted and supported physical activity seems crucial for the maintenance of physical functions in these vulnerable elderly persons.

<b><i>Background:</i></b> Nursing home residents are extremely inactive and deterioration in health and an increasing dependence in activities of daily living (ADL) are common. Physical activity and exercise play a major role in the preservation of physical function and quality of life late in life. However, evidence for the benefit of rehabilitation in nursing home residents is conflicting and inconclusive. <b><i>Objective:</i></b> To evaluate the effect of an individually tailored intervention program of 3 months, for nursing home residents, on ADL, balance, physical activity level, mobility and muscle strength. <b><i>Methods:</i></b> In this single-blind randomized clinical trial with parallel groups, nursing home residents >64 years of age from three Nordic countries were included. The intervention group (IG) was assigned to individually tailored physical and daily activities, while the control group (CG) received ordinary care. Primary outcomes were ADL and balance, and secondary outcomes physical activity level, mobility and muscle strength. <b><i>Results:</i></b> At baseline, 322 nursing home residents were included, of whom 266 were assessed after 3 months of intervention. Following the intervention, a significant difference was found between participants in the IG and CG on measures of balance, physical activity and transfers. The IG significantly improved walking/wheelchair speed and functional leg muscle strength. The CG had significantly deteriorated in ADL, balance and transfers. Persons who had taken part in the intervention for more than 150 min/week significantly improved their balance and physical activity level. Participation in more than 10 weeks of intervention significantly improved physical activity and walking/wheelchair speed, while a deterioration was seen in those who had participated less. <b><i>Conclusion:</i></b> Individually tailored intervention in nursing home residents focusing on physical and daily activities is effective in improving transfers, balance and physical activity level compared to usual care. The effect of the intervention is dependent on the total activity time.