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P Houx

Publications and source records attributed to P Houx.

8 recordsLinked to original sources
PubMed2003

Interaction of atherosclerosis and inflammation in elderly subjects with poor cognitive function.

OBJECTIVE: To test the hypothesis that a pro-inflammatory response is associated with cognitive impairment among individuals with cardiovascular disease. METHOD: All 85-year-old inhabitants of Leiden (n = 599) were visited at their place of residence. A history of cardiovascular disease and an EKG were used as indicators of atherosclerosis. Production of the pro-inflammatory cytokine tumor necrosis factor-alpha and the anti-inflammatory cytokine interleukin-10 was assessed in a whole-blood assay using lipopolysaccharide as a stimulus. Global cognitive functioning was determined with the Mini-Mental State Examination (MMSE); attention, cognitive speed, and memory were determined with four neuropsychological tests; and a history of dementia was obtained. RESULTS: In subjects with cardiovascular disease, median MMSE scores were lower in those with a pro-inflammatory response when compared with those with an anti-inflammatory response (p = 0.02). Similar associations were found for the Stroop Test, measuring attention (p < 0.01), the Coding Test measuring cognitive speed (p = 0.02), the Word Learning Test measuring memory (p < 0.01), and the presence of dementia (p = 0.04). The associations remained unaltered after adjustments for possible confounders such as gender, level of education, use of nonsteroidal anti-inflammatory drugs, use of cardiovascular drugs, and cardiovascular risk factors. In contrast, outcomes of the cognitive tests and presence of dementia were not dependent on the inflammatory response when cardiovascular disease was absent. CONCLUSION: The combination of cardiovascular disease and a pro-inflammatory cytokine response may be associated with cognitive impairment and dementia.

Aged↗
PubMed2002

Atherosclerosis and cognitive impairment are linked in the elderly. The Leiden 85-plus Study.

Post-mortem analyses suggest that atherosclerosis more often contributes to late-onset dementia than hitherto expected. We set out to further unravel the relation between atherosclerosis and cognitive impairment. We therefore tested the hypothesis that the number of cardiovascular pathologies is positively associated with cognitive impairment in elderly subjects, and that the smaller number of cardiovascular pathologies in women explains the better cognitive function of elderly women. Within the Leiden 85-plus Study, we assessed the atherosclerotic burden by counting the number of cardiovascular pathologies in the medical histories of a population-based sample of 599 subjects aged 85 years (response 87%). Significantly more men than women had a history of cardiovascular pathologies (67% compared to 59%, P<0.001). In addition, cognitive function was assessed. All subjects completed the Mini-Mental State Examination (MMSE). Cognitive speed and memory were determined with specific neuro-psychological tests in those with a MMSE-score above 18 points. There was a highly significant dose-response relationship between the number of cardiovascular pathologies and cognitive impairment for both men and women. The median MMSE-score was 26 points in subjects without cardiovascular disease and decreased to 25 points for subjects who had two or more cardiovascular pathologies (P for trend =0.003). Similar associations were found for cognitive speed but not for memory. Our data confirm that in old age atherosclerosis significantly contributes to cognitive impairment. Since treatments for atherosclerosis appear to be particularly effective in elderly people, we consider our finding of utmost clinical importance in possibly preventing cognitive impairment and late-onset dementia.

Aged↗
PubMed2001

The assessment of postoperative cognitive function.

Postoperative cognitive function (POCD) has been subject to extensive research. In the literature, large differences are apparent in methodology such as the test batteries, the interval between sessions, the endpoints to be analysed, statistical methods, and how neuropsychological deficits are defined. Traditionally, intelligence tests or tests developed for clinical neuropsychology have been used. The tests for detecting POCD should be based on well-described sensitivity and suitability in relation to surgical patients. In tests using scores, floor/ceiling effects may compromise the evaluation if the tests are either too easy or to difficult. Uncontrolled testing facilities and change of test personnel may affect the test performance. Practice effects are pronounced in neuropsychological tests but have generally been ignored. The use of a suitable normative population is essential to allow correction for practice effects and variability between sessions. Missing follow-up may severely compromise valid conclusions since subjects unable or unwilling to be examined are particularly prone to suffer from POCD. In the statistical analysis of the test results, the evaluation should be based on differences between pre- and postoperative performance. Parametric statistical tests are not relevant unless the appropriate Gaussian distributions are present, perhaps after transformation of data. The definition of cognitive dysfunction should be restrictive and the criteria should be fulfilled in only a small proportion of volunteers. In the literature, these requirements often have not been fulfilled. This precludes a reasonable estimation of the incidence of POCD and the conclusions of comparative studies should be interpreted with great caution. In this review article, we present a number of recommendations for the design and execution of studies within this area. In addition, the critical reader may use these recommendations in the evaluation of the literature.

Affect↗
PubMed2001

Cognitive function in the oldest old: women perform better than men.

OBJECTIVE: Limited formal education is associated with poor cognitive function. This could explain sex differences in cognitive function in the oldest old. Whether limited formal education explains differences in cognitive function between elderly women and men was explored. METHODS: The Leiden 85-plus Study is a population based study investigating all 85 year old inhabitants of Leiden with an overall response rate of 87%. A sample of 599 participants were visited at their place of residence. The mini mental state examination was completed by all participants. Cognitive speed and memory were determined with four neuropsychological tests in participants with a mini mental state examination score higher than 18 points. RESULTS: The proportion of women with limited formal education was significantly higher than that of men (70% v 53%, p=0.001), but women had better scores for cognitive speed and memory than men (p<0.05). After adjustment for differences in limited formal education and the presence of depressive symptoms, the odds ratio for women to have a higher cognitive speed than men was 1.7 (95% CI; 1.0 to 2.6), and for them to have a better memory the odds ratio was 1.8 (95%CI; 1.2 to 2.7). CONCLUSION: Women have a better cognitive function than men, despite their lower level of formal education. Limited formal education alone, therefore, cannot explain the differences in cognitive function in women and men. These findings support the alternative hypothesis that biological differences, such as atherosclerosis, between women and men account for the sex differences in cognitive decline.

Aged↗
PubMed1998

Long-term postoperative cognitive dysfunction in the elderly ISPOCD1 study. ISPOCD investigators. International Study of Post-Operative Cognitive Dysfunction.

BACKGROUND: Long-term postoperative cognitive dysfunction may occur in the elderly. Age may be a risk factor and hypoxaemia and arterial hypotension causative factors. We investigated these hypotheses in an international multicentre study. METHODS: 1218 patients aged at least 60 years completed neuropsychological tests before and 1 week and 3 months after major non-cardiac surgery. We measured oxygen saturation by continuous pulse oximetry before surgery and throughout the day of and the first 3 nights after surgery. We recorded blood pressure every 3 min by oscillometry during the operation and every 15-30 min for the rest of that day and night. We identified postoperative cognitive dysfunction with neuropsychological tests compared with controls recruited from the UK (n=176) and the same countries as study centres (n=145). FINDINGS: Postoperative cognitive dysfunction was present in 266 (25.8% [95% CI 23.1-28.5]) of patients 1 week after surgery and in 94 (9.9% [8.1-12.0]) 3 months after surgery, compared with 3.4% and 2.8%, respectively, of UK controls (p<0.0001 and p=0.0037, respectively). Increasing age and duration of anaesthesia, little education, a second operation, postoperative infections, and respiratory complications were risk factors for early postoperative cognitive dysfunction, but only age was a risk factor for late postoperative cognitive dysfunction. Hypoxaemia and hypotension were not significant risk factors at any time. INTERPRETATION: Our findings have implications for studies of the causes of cognitive decline and, in clinical practice, for the information given to patients before surgery.

Abdomen↗
PubMed1990

Cortisol reactivity and cognitive performance in a continuous mental task paradigm.

The after-effects of fatigue or stress on the performance of cognitive tests have been particularly difficult to demonstrate. In this study we examined whether salivary cortisol, used as an index of stress evoked by the continuous performance of mental tasks, reflected individual differences in cognitive performance. In a within-subject experiment in which 24 subjects were exposed to 4 hours of continuous mental activity and to a control session, significantly higher cortisol levels were found during the continuous task session. Cognitive performance was assessed before and after each session. The relevant test parameters involved aspects of verbal memory, concept shifting and divided attention. When subjects were divided into two groups based on the magnitude of individual cortisol responses to the continuous tasks, it was found that the subgroup with higher cortisol responses decreased in attention compared with their attention after the control session. In contrast, the performance of the subgroup with no or lower cortisol responses did not differ between the two sessions. There was no evidence of similar effects on verbal memory or concept shifting.

Adult↗
PubMed1989

Effects of an overnight fluid infusion on cognitive functions in preoperative patients.

The results of the present study show that subjects who received an overnight infusion of isotonic fluid did significantly less well at particular neuropsychological tests than controls who did not receive such an infusion. The relevant test parameters involved aspects of word list learning, and concept shifting on a complex speed task. Potentially biasing factors such as anxiety, disturbed sleep, education and age could be discarded. With respect to the physiological mechanism involved, the results suggest that a relatively expanded extracellular volume without dilutional hyponatremia might underlie the diminished performance. The experimental group did not lose weight overnight, and the hemoglobin and haematocrit level of the experimental group were significantly different from those of the control group; the blood pressure, plasma electrolytes and osmolality were not different. The present results provide evidence that disturbances in fluid homeostasis may affect cognitive performance.

Adult↗