Hormone replacement therapy to maintain cognitive function in women with dementia

BACKGROUND

As estrogens have been shown to have several potentially beneficial effects on the central nervous system, it is biologically plausible that maintaining high levels of estrogens in postmenopausal women by means of estrogen replacement therapy (ERT) could be protective against cognitive decline and the development of Alzheimer's disease (AD) or other dementia syndromes.

OBJECTIVES

To investigate the effects of ERT (estrogens only) or HRT (estrogens combined with a progestagen) compared with placebo in randomized controlled trials (RCTs) on cognitive function of postmenopausal women with dementia.

SEARCH STRATEGY

The CDCIG Specialized Register, which contains up-to-date records from many medical databases was searched using the terms ORT, PORT, ERT, HRT, estrogen*, oestrogen*, progesteron* and Alzheim* on 16th of May 2002. In addition, MEDLINE (1966-2002/01); EMBASE (1985-2002/01); and PsyINFO (1967-2002/01) were searched.

SELECTION CRITERIA

All double-blind randomized controlled trials (RCTs) into the effect of ERT or HRT for cognitive function with a treatment period of at least two weeks in postmenopausal women with AD or other types of dementia.

DATA COLLECTION AND ANALYSIS

Abstracts of the references retrieved by the searches were read by two reviewers (EH and KY) independently in order to discard those that were clearly not eligible for inclusion. The two reviewers studied the full text of the remaining references and independently selected studies for inclusion. Any disparity in the ensuing lists was resolved by discussion with all reviewers in order to arrive at the final list of included studies. The selection criteria ensured that the blinding and randomization of the included studies was adequate. The two reviewers also assessed the quality of other aspects of the included trials. One reviewer (EH) extracted the data from the studies, but was aided and checked by JB from Cochrane.

MAIN RESULTS

A total of five trials including 210 women with AD were analysed. Meta-analyses showed that there was a limited positive effect from low dosage of conjugated equine estrogens (CEE, 0.625 mg once a day) but not from higher dosage (1.25 mg of CEE once a day) on the Mini-Mental Status Examination after 2 months (WMD=1.28, 95% C.I.=0.26 to 2.30, z=2.45, p<0.01) and the effect disappeared after 3, 6 and 12 months of treatment. This effect was small and not clinically relevant as there was only a difference of 1 point on average in comparison with the placebo users (the scale range is 0-30). There were also short-term effects of 1.25 mg of CEE on tests of concentration and executive function, namely the Trail Making Test-B (WMD=-40.90, 95% C.I.-79.29 to -2.51, z=2.09, p<0.05) and Digit Span backward (WMD=0.67, 95% C.I.=-0.01 to 1.34, z=1.94, p<0.05). With regard to memory, only cued delayed recall of a word list was positively affected by 2 months of transdermal diestradiol (E2) (WMD=6.50, 95% C.I.=4.04 to 8.96, z=5.19, p<0.0001). No HRT effects were seen on other word lists, Paragraph Recall or Paired Associate Learning. In addition, no effects were seen on visual memory, language functions, most speeded tests, clinical rating scales or depression. Controls had better performance on the delayed recall of the Paragraph Test (overall WMD=-0.45, 95% C.I.=-0.79 to -0.11, z=2.60, p<0.01) after 1 month and on Finger Tapping after 12 months (WMD=-3.90, 95% C.I.=-7.85 to 0.05, z=1.93, p<0.05). Clinicians also gave controls a better score on a dementia rating scale (CDR, overall WMD=0.35, 95% C.I.=0.01 to 0.69, z=1.99, p<0.05). Positive findings in favour of treatment or placebo could have been random effects caused by multiple analyses. After correction for multiple testing, only the short-term positive treatment effect of E2 on memory remained.

REVIEWER'S CONCLUSIONS

Currently, HRT or ERT for cognitive improvement or maintenance is not indicated for women with AD. As we did not have data on women with other types of dementia (e.g. vascular dementia) this remains to be investigated. As most studies only used CEE and our earlier review in healthy women found effects only after a bolus injection of E2, it remains possible that different preparations or types of ERT or HRT could have a different effects. Several questions are raised in this review, including whether factors such as age, dementia onset (early AD), or the use of a particular preparation for a longer duration of treatment could have different effects. Perhaps the most important question is whether ERT or HRT can delay the time of onset of dementia. For answers to these questions, we have to await the results of the large RCTs currently in progress in the UK, USA, and Canada.

Long-term affective disorder in people with mild learning disability

BACKGROUND

Increased risk of affective disorder in learning disability has been reported, although the extent to which this is due to adverse social and material circumstances is uncertain and there have been potential limitations in the measurement of affective disorder.

AIMS

To determine risk of affective disorder in those classified with mild learning disability in the British 1946 birth cohort and to investigate whether this risk was accounted for by disadvantage in childhood and adulthood.

METHOD

Learning disability was defined as the equivalent of an IQ < or =69 at age 15 years. The Present State Examination at age 36 years and the Psychiatric Symptom Frequency Scale at age 43 years provided psychiatric outcome measures.

RESULTS

Learning disability was associated with a fourfold increase in risk of affective disorder, not accounted for by social and material disadvantage or by medical disorder.

CONCLUSIONS

Learning disability is strongly associated with risk of affective disorder, persisting well into midlife.

Fatigue in patients with cancers of the breast or prostate undergoing radical radiotherapy

To determine the prevalence, severity, and correlates of fatigue among patients with cancers of the prostate or breast receiving high dose radiotherapy with curative intent, a prospective, questionnaire-based study evaluated a convenience sample of 62 patients who were about to start a course of radiotherapy. Patients were assessed immediately prior to treatment, and again within a week of finishing. Fatigue was assessed using the Fatigue Severity Scale (FSS) and the Bidimensional Fatigue Scale (BFS). Quality of life was assessed using the European Organisation for Research and Treatment of Cancer 30-item Quality of Life Questionnaire (EORTC QLQc30). Psychological distress was assessed using the Hospital Anxiety and Depression Scale (HADS). Personality Traits were assessed using the Eysenck Personality Inventory (EPI). Fatigue severity increased significantly on 3 out of the 5 assessment instruments used. Radiotherapy was associated with a decline in global quality of life, role, cognitive and social functioning, and an increase in nausea/vomiting, pain, insomnia, diarrhea, and financial difficulty. At baseline, 39% of the variation in fatigue scores among the patients could be explained by a combination of measures of their global quality of life and physical functioning. A combination of fatigue and anxiety scores at baseline was able to predict 54% of the variation in fatigue scores at the completion of radiotherapy. These data indicate that fatigue is a significant problem for patients receiving radical radiotherapy, although its severity is relatively modest.

Do the four clades of the mtDNA haplogroup L2 evolve at different rates?

Forty-seven mtDNAs collected in the Dominican Republic and belonging to the African-specific haplogroup L2 were studied by high-resolution RFLP and control-region sequence analyses. Four sets of diagnostic markers that subdivide L2 into four clades (L2a-L2d) were identified, and a survey of published African data sets appears to indicate that these clades encompass all L2 mtDNAs and harbor very different geographic/ethnic distributions. One mtDNA from each of the four clades was completely sequenced by means of a new sequencing protocol that minimizes time and expense. The phylogeny of the L2 complete sequences showed that the two mtDNAs from L2b and L2d seem disproportionately derived, compared with those from L2a and L2c. This result is not consistent with a simple model of neutral evolution with a uniform molecular clock. The pattern of nonsynonymous versus synonymous substitutions hints at a role for selection in the evolution of human mtDNA. Regardless of whether selection is shaping the evolution of modern human mtDNAs, the population screening of L2 mtDNAs for the mutations identified by our complete sequence study should allow the identification of marker motifs of younger age with more restricted geographic distributions, thus providing new clues about African prehistory and the origin and relationships of African ethnic groups.

Creating a career ladder for nursing assistants in long-term care

This article describes the development, implementation, and evaluation of a career ladder for certified nursing assistants in long-term care. A career ladder is an effective way to maximize the use of unlicensed workers without changing the skill mix (eg, no loss of licensed nursing positions) and allow the licensed nurse more time to perform higher-level clinical tasks, such as assessments, patient education, and documentation. Implementation of an unlicensed worker career ladder also can improve nursing assistant retention.

Detecting errors in mtDNA data by phylogenetic analysis

Sequencing and documenting a sample of homologous DNA stretches is prone to copying errors in a way rather analogous to the biological replication process. Previous attempts at obtaining representative mtDNA sequences, typically of the control region, for evolutionary studies or forensic purposes have yielded rather unsatisfactory results in many cases. The key ingredient in pinpointing problems with given data is the phylogenetic analysis of closely related mtDNAs within the framework of an established worldwide phylogeny that is supported by coding region information. We develop some general rules by which likely errors in data tables can readily be detected without rereading whole sequences repeatedly. Following these guidelines, one can expect to lower the error rate by at least an order of magnitude, although it will still be hard to beat the mitochondrial gamma polymerase in precision.

Apolipoprotein E genotype, vascular risk and early cognitive impairment in an African Caribbean population

A reduced risk of Alzheimer's disease (AD) associated with the apolipoprotein E (APOE) epsilon4 allele is reported in populations of African origin. In order to clarify possible reasons for this, we examined the association between APOE genotype and early cognitive impairment in a community-based African Caribbean UK population aged 55-75 years. APOE genotype was available for 202 participants, 57 (28%) of whom were classified as having relative cognitive impairment on a battery of neuropsychological tests. Cognitive impairment was negatively associated with epsilon2 and positively but more weakly associated with epsilon4. Effects of both alleles increased markedly after age 70. The effect of epsilon4 was increased in combination with hypertension, diabetes or lower educational attainment, but these factors did not influence epsilon2 effects. Cholesterol and triglyceride levels partially explained effects of epsilon2, but did not account for those of epsilon4. A reduced association between epsilon4 and later AD in populations of African origin is unlikely to be explained by reduced cognitive effects or by differential mortality. However, it may be accounted for by vascular comorbidity. The different patterns of association between epsilon2 and epsilon4 alleles suggest different pathways of effect.

Air pollution and birth weight in Britain in 1946

Recent studies suggested that air pollution might be related to low birth weight. We tested this hypothesis on data from the British 1946 birth cohort. We found a strong association between birth weight and an air pollution index based on coal consumption. Babies born in the most polluted areas were on average 87 grams lighter than those born in the areas with the cleanest air. Adjustment for a number of sociodemographic factors did not change these estimates. While confounding by unmeasured factors cannot be ruled out, these historical data support the hypothesis that birth weight could be affected by air pollution.

Cognitive function in UK community-dwelling African Caribbean elders: normative data for a test battery

Many 'first generation' African Caribbean residents in the UK have now reached ages where risk of cognitive impairment and dementia starts to increase. In addition, conditions which may impair cognitive function, such as hypertension, diabetes and stroke, have high prevalence rates in African Caribbean populations. However, there is a lack of normative data for cognitive tests in this ethnic group. Cognitive assessment was carried out in a south London community population of 285 African Caribbean participants aged 55-75 years. Tests were drawn principally from the consortium to establish a registry for Alzheimer's disease (CERAD) battery (Boston Naming Test, verbal fluency, word list recall, and Trailmaking Tests A and B) and also included orientation items from the Mini-Mental State Examination (MMSE) and the Clock Drawing Test. Independent effects of age, sex, education and occupation were identified on scores for most but not all cognitive tests. Compared with normative data for African American populations, lower scores on verbal fluency and the Boston Naming Test were observed but scores on memory tests were comparable. Normative data for the tests are presented, stratified by level of education.

Genetic evidence for different male and female roles during cultural transitions in the British Isles

Human history is punctuated by periods of rapid cultural change. Although archeologists have developed a range of models to describe cultural transitions, in most real examples we do not know whether the processes involved the movement of people or the movement of culture only. With a series of relatively well defined cultural transitions, the British Isles present an ideal opportunity to assess the demographic context of cultural change. Important transitions after the first Paleolithic settlements include the Neolithic, the development of Iron Age cultures, and various historical invasions from continental Europe. Here we show that patterns of Y-chromosome variation indicate that the Neolithic and Iron Age transitions in the British Isles occurred without large-scale male movements. The more recent invasions from Scandinavia, on the other hand, appear to have left a significant paternal genetic legacy. In contrast, patterns of mtDNA and X-chromosome variation indicate that one or more of these pre-Anglo-Saxon cultural revolutions had a major effect on the maternal genetic heritage of the British Isles.

Elevated plasma cholecystokinin at high altitude: metabolic implications for the anorexia of acute mountain sickness

The aims of the present study were to measure the satiety neuropeptide cholecystokinin (CCK) in humans at terrestrial high altitude to investigate its possible role in the pathophysiology of anorexia, cachexia, and acute mountain sickness (AMS). Nineteen male mountaineers aged 38 +/- 12 years participated in a 20 +/- 5 day trek to Mt. Kanchenjunga basecamp (BC) located at 5,100 m, where they remained for 7 +/- 5 days. Subjects were examined at rest and during a maximal exercise test at sea-level before/after the expedition (SL1/SL2) and during the BC sojourn. There was a mild increase in Lake Louise AMS score from 1.1 +/- 1.2 points at SL1 to 2.3 +/- 2.3 points by the end of the first day at BC (P < 0.05). A marked increase in resting plasma CCK was observed on the morning of the second day at BC relative to sea-level control values (62.9 +/- 42.2 pmol/L(-1) vs. SL1: 4.3 +/- 8.3 pmol/L(-1), P < 0.05 vs. SL2: 26.5 +/- 25.2 pmol/L(-1), P < 0.05). Maximal exercise increased CCK by 78.5 +/- 24.8 pmol/L(-1), (P < 0.05 vs. resting value) during the SL1 test and increased the plasma concentration of non-esterified fatty acids and glycerol at BC (P < 0.05 vs. SL1/SL2). The CCK response was not different in five subjects who presented with anorexia on Day 2 compared with those with a normal appetite. While there was no relationship between the increase in CCK and AMS score at BC, a more pronounced increase in resting CCK was observed in subjects with AMS (> or =3 points at the end of Day 1 at BC) compared with those without (+98.9 +/- 1.4 pmol/L(-1) vs. +67.6 +/- 37.2 pmol/L(-1), P < 0.05). Caloric intake remained remarkably low during the stay at BC (8.9 +/- 1.4 MJ.d(-1)) despite a progressive decrease in total body mass (-4.5 +/- 2.1 kg after 31 +/- 13 h at BC, P < 0.05 vs. SL1/SL2), which appeared to be due to a selective loss of torso adipose tissue. These findings suggest that the satiogenic effects of CCK may have contributed to the observed caloric deficit and subsequent cachexia at high altitude despite adequate availability of palatable foods. The metabolic implications of elevated CCK in AMS remain to be elucidated.

Depression, APOE genotype and subjective memory impairment: a cross-sectional study in an African-Caribbean population

BACKGROUND

Subjective memory impairment (SMI) is common in older populations but its aetiology and clinical significance is uncertain. Depression has been reported to be strongly associated with SMI. Associations with objective cognitive impairment are less clear cut. Other factors suggested to be associated with SMI include poor physical health and the apolipoprotein E (APOE) epsilon4 allele. Studies of SMI have been predominantly confined to white Caucasian populations.

METHOD

A community study was carried out in a UK African-Caribbean population aged 55-75, sampled from primary care lists. Twenty-three per cent were classified with SMI. Depression was defined using the 10-item Geriatric Depression Scale. Other aetiological factors investigated were education, objective cognitive function, APOE genotype, disablement and vascular disease/risk. The principal analysis was restricted to 243 participants scoring > 20 on the Mini-Mental State Examination (85%). A second analysis included all 290 participants.

RESULTS

Depression, self-reported physical impairment and APOE epsilon4 were associated with SMI. The association between SMI and physical impairment was not explained by depression, vascular disease/risk, or disability/handicap. The association between epsilon4 and SMI increased as MMSE scores decreased and was particularly strong in those with depression. The epsilon4 allele was present in 69% (95% CI 41-89%) of those with depression and SMI compared with 28% (20-36%) of those with neither.

CONCLUSIONS

Depression may not be a sufficient explanation for subjective memory complaints. Memory complaints in the presence of depression are associated with high prevalence of epsilon4 and therefore, presumably, a raised risk of subsequent dementia.

Identification and management of intravagal parathyroid adenoma

Intravagal parathyroid adenomas are rare, with only three cases reported in the English literature. The objective of this report is to describe two additional patients with hyperfunctioning parathyroid glands found within the vagus nerve and to define the anatomy of this finding. Both patients presented with a history of persistent hyperparathyroidism despite multiple therapeutic interventions. A high cervical localization was established in both cases by selective venous sampling. In each patient successful removal of the intravagal parathyroid gland was achieved with subsequent resolution of calcium and parathyroid levels. Each adenoma was located within the vagus nerve below the level of the carotid bifurcation and was enucleated without sacrificing the vagus nerve. In our cases and those reported previously, the parathyroid glands were supernumerary, representing parathyroid tissue embryologically derived from the third branchial pouch. Exploration for hyperparathyroidism requires a complete, meticulous surgical dissection to identify all parathyroid glands and to search for possible accessory tissue in selected cases. Our experience and a review of the literature serve to emphasize that, although rare, intravagal parathyroid adenomas do occur. Examination of the vagus nerve should therefore be strongly considered when four normal glands are found, as intravagal adenomas appear to represent accessory ectopically located parathyroid tissue.

Neuronal sodium-channel alpha1-subunit mutations in generalized epilepsy with febrile seizures plus

Generalized epilepsy with febrile seizures plus (GEFS+) is a familial epilepsy syndrome characterized by the presence of febrile and afebrile seizures. The first gene, GEFS1, was mapped to chromosome 19q and was identified as the sodium-channel beta1-subunit, SCN1B. A second locus on chromosome 2q, GEFS2, was recently identified as the sodium-channel alpha1-subunit, SCN1A. Single-stranded conformation analysis (SSCA) of SCN1A was performed in 53 unrelated index cases to estimate the frequency of mutations in patients with GEFS+. No mutations were found in 17 isolated cases of GEFS+. Three novel SCN1A mutations-D188V, V1353L, and I1656M-were found in 36 familial cases; of the remaining 33 families, 3 had mutations in SCN1B. On the basis of SSCA, the combined frequency of SCN1A and SCN1B mutations in familial cases of GEFS+ was found to be 17%.

Vascular risk and cognitive impairment in an older, British, African-Caribbean population

OBJECTIVES

In an older, British, African-Caribbean population with high prevalence rates of hypertension and diabetes mellitus, we ascertained clinical vascular disease (stroke or ischemic heart disease) and vascular risk (including hypertension, diabetes, and lipid profile) and investigated their associations with cognitive impairment.

DESIGN

Cross-sectional community-based study.

SETTING

The sample was drawn from registration lists for seven primary care services in south London, United Kingdom.

PARTICIPANTS

278 individuals, age 55 to 75, who were born in a Caribbean nation.

MEASUREMENTS

Participants were interviewed and examined for cardiovascular risk factors, including a blood test for lipid profile and fibrinogen. A battery of 11 psychometric tests was administered blind to medical status. Cognitive impairment was defined on the basis of a composite measure derived from individual test scores.

RESULTS

Seventy-nine (28%) subjects were classified as having relative cognitive impairment and were compared with the remainder of the sample. Marked differences were seen between low and normal/high educational levels in the strength of associations between measures of vascular risk and cognitive impairment. Hypertension, diabetes, and raised triglycerides were significant factors in those with lower levels of education. Low fibrinogen (negatively associated), high cholesterol, and manual occupation were significant factors in those with normal/high levels of education. Physical exercise was negatively associated with cognitive impairment: an association that persisted after adjustment for age, occupation, depression, and physical disability and after excluding subjects with the most severe imipairment.

CONCLUSION

Measures of vascular risk were associated with relative cognitive impairment in this population. These associations were modified by previous educational attainment. Physical activity was negatively associated with cognitive impairment.

Birth weight and cognitive function in the British 1946 birth cohort: longitudinal population based study

OBJECTIVE

To examine the association between birth weight and cognitive function in the normal population.

DESIGN

A longitudinal, population based, birth cohort study.

PARTICIPANTS

3900 males and females born in 1946.

MAIN OUTCOME MEASURES

Cognitive function from childhood to middle life (measured at ages 8, 11, 15, 26, and 43 years).

RESULTS

Birth weight was significantly and positively associated with cognitive ability at age 8 (with an estimated standard deviation score of 0.44 (95% confidence interval 0.28 to 0.59)) between the lowest and highest birthweight categories after sex, father's social class, mother's education, and birth order were controlled for. This association was evident across the normal birthweight range (>2.5 kg) and so was not accounted for exclusively by low birth weight. The association was also observed at ages 11, 15, and 26, and weakly at age 43, although these associations were dependent on the association at age 8. Birth weight was also associated with education, with those of higher birth weight more likely to have achieved higher qualifications, and this effect was accounted for partly by cognitive function at age 8.

CONCLUSIONS

Birth weight was associated with cognitive ability at age 8 in the general population, and in the normal birthweight range. The effect at this age largely explains associations between birth weight and cognitive function at subsequent ages. Similarly, the association between birth weight and education was accounted for partly by earlier cognitive scores.

C-type natriuretic peptide expression in olfactory regions of rat brain is modulated by acute water deprivation, salt loading and central angiotensin II

To elucidate the central role of c-type natriuretic peptide (CNP), levels of CNP mRNA in control rat brain were compared with levels following acute water deprivation, salt loading and central administration of angiotensin II (AII), using Northern blot and in situ hybridisation. Rats with water deprivation (WD) had no access to water for 48 h, rats with salt loading (SL) had access to 2% saline for 48 h, and control rats had free access to water. Both WD and SL significantly raised plasma sodium (Na). Levels of CNP mRNA in olfactory regions were significantly decreased in WD and increased in SL. In the medulla, WD and SL both increased CNP mRNA, but levels of CNP mRNA elsewhere in the brain were not significantly altered. Intracerebroventricular AII (500 ng) increased water intake, and induced a significant increase in CNP expression at 4 h in olfactory regions, but not in other brain sites. In summary, CNP expression is regulated in olfactory regions of the rat brain in response to acute challenges to water and salt balance and by central AII.