Metabolic Syndrome and the Risk of Mild Cognitive Impairment and Progression to Dementia: Follow-up of the Singapore Longitudinal Ageing Study Cohort.

IMPORTANCE: The association of the metabolic syndrome (MetS) and component cardiovascular risk factors with the risk of developing mild cognitive impairment (MCI) and MCI progression to dementia is not well established. OBJECTIVE: To investigate the association of the MetS and its component cardiovascular risk factors with the incidence of MCI and its progression to dementia. DESIGN, SETTING, AND PARTICIPANTS: Prospective longitudinal study from September 1, 2003, through December 31, 2009, in communities in 5 districts in the South East region of Singapore. Study participants were a population-based sample of 1519 cognitively normal adults 55 years and older. MAIN OUTCOMES AND MEASURES: Prespecified outcomes were incident MCI and MCI progression to dementia. RESULTS: The study cohort comprised 1519 participants. Their mean (SD) age was 64.9 (6.8) years, and 64.8% (n = 984) were female. Baseline characteristics associated with an increased risk of incident MCI were MetS (hazard ratio [HR], 1.46; 95% CI, 1.02-2.09), central obesity (HR, 1.41; 95% CI, 1.01-1.98), diabetes mellitus (HR, 2.84; 95% CI, 1.92-4.19), dyslipidemia (HR, 1.48; 95% CI, 1.01-2.15), and 3 or more component cardiovascular risk factors (HR, 1.58; 95% CI, 1.13-2.33). Baseline characteristics associated with an increased risk of MCI progression to dementia were MetS (HR, 4.25; 95% CI, 1.29-14.00), diabetes mellitus (HR, 2.47; 95% CI, 1.92-4.19), and 3 or more component cardiovascular risk factors (HR, 4.92; 95% CI, 1.39-17.4). CONCLUSIONS AND RELEVANCE: The MetS was associated with an increased incidence of MCI and progression to dementia. Identifying individuals with diabetes mellitus or the MetS with or without MCI is a promising approach in early interventions to prevent or slow progression to dementia.

Novel inflammatory markers associated with cognitive performance: Singapore Longitudinal Ageing Studies.

We identified and validated several novel inflammatory markers of cognitive performance in community-living older persons. An exploratory study (n = 83) correlated 177 inflammatory markers assayed by Luminex with the Mini-Mental State Examination (MMSE) and identified 8 inflammatory markers for enzyme-linked immunosorbent assay (ELISA) and correlations with MMSE, Montreal Cognitive Assessment (MoCA), and cognitive impairment in the validation study (n = 139). The validation study replicated the significant associations of soluble interleukin-2 receptor alpha chain (sIL-2Rα; p = 0.050), soluble tumor necrosis factor receptor 2 (sTNFR2; p = 0.002) and soluble glycoprotein 130 (sgp130; p = 0.026) with MMSE, and sIL-2Rα (p = 0.019) and sgp130 (p < 0.001) with MoCA. Significant trends of associations of tertiles of sgp130, sIL-2Rα, and sTNFR2 were found with cognitive impairment. Highly elevated estimates of association of high versus low tertiles were obtained for sgp130 (odds ratio [OR] = 4.24, 95% confidence interval [CI] 0.96-18.8), sIL-2Rα (OR = 3.94, 95% CI 0.83-18.7), and sTNFR2 (OR = 7.58, 95% CI 1.19-48.1). sgp130, sTNFR2, and sIL-2Rα are promising inflammatory markers of low cognitive performance for further investigation.

Insomnia and daytime neuropsychological test performance in older adults.

OBJECTIVES/BACKGROUND: There is good documentation of the impact of insomnia on daytime cognitive function based on self-reports, but not on neuropsychological test performance. The study investigated the association of difficulty initiating sleep (DIS), difficulty maintaining sleep (DMS), and early morning awakening (EMA) complaints with daytime domain-specific neuropsychological performance in older adults. PARTICIPANTS/METHODS: Participants were 859 older adults (mean 71.9 years) in the Singapore Longitudinal Ageing Studies. They were interviewed and assessed at community-based eldercare activity centres and completed a sleep survey questionnaire and a battery of neuropsychological tests (Digit span, Rey Auditory Verbal Learning Test, Story memory, Brief Visuospatial Memory Test-Revised, Color Trails Test (1 and 2), Block design, and Verbal fluency). RESULTS: Insomnia complaints were present in 18.0% (n = 155) of participants. Controlling for the presence of other insomnia complaints, psychosocial and medical variables, and depression, EMA was independently and significantly associated with worse executive functioning (p = 0.031). DIS and DMS were not independently associated with poorer performance on any cognitive domain. CONCLUSION: The association of EMA among older adults with decreased executive functioning and underlying mechanistic factors should be further investigated.

Vascular Health Indices and Cognitive Domain Function: Singapore Longitudinal Ageing Studies.

BACKGROUND: Few studies have comprehensively evaluated the relationship between vascular disease and cognition of older adults without cardiac disease. OBJECTIVE: We explored the associations of structural atherosclerosis, vascular stiffness, and reactivity with global, memory, attention, language, visuospatial ability, and executive function in community-dwelling, non-demented older Asians without cardiac diseases. METHODS: Cognition was assessed by Mini-Mental State Examination (MMSE) (n = 308) and detailed neuropsychological tests (n = 155). Vascular measures included carotid intima-media thickness; aortic stiffness [carotid-femoral pulse wave velocity (CFPWV), aortic augmentation index (AI), and aortic pulse pressure (PP)]; carotid stiffness [elasticity modulus (Ep), beta index (ß), arterial compliance (AC), carotid AI]; and endothelial function [reactive hyperemia index (RHI)]. Multivariable analyses controlled for potential confounding by demographics, apolipoprotein E genotype and cardiovascular risk factors. RESULTS: The participants' mean age was 63.0 ± 6.1 years. Inverse associations with MMSE were found for AC (ß= 0.128, p = 0.019), Ep (ß= -0.151, p = 0.008), ß index (ß= -0.122, p = 0.029), carotid stiffness z-score (ß= -0.154, p = 0.007); with executive function for CFPWV (ß= -0.209, p = 0.026), AC (ß= 0.214, p = 0.005), Ep (ß= -0.160, p = 0.050), ß index (ß= -0.165, p = 0.041), and both aortic (ß= -0.229, p = 0.010) and carotid (ß= -0.208, p = 0.010) stiffness z-scores; with verbal memory for AI (ß= -0.229, p = 0.004) and aortic (ß= -0.263, p = 0.004) stiffness z-score; with language for AI (ß= -0.155, p = 0.025), aortic stiffness z-score (ß= -0.196, p = 0.011). RHI positively correlated with visuospatial ability (ß= 0.195, p = 0.013) and executive function (ß= 0.151, p = 0.045). CONCLUSION: The results support a link between systemic vascular health and neurocognitive function in older Asian adults. Subclinical noninvasive measures of arterial stiffness and reactivity may identify individuals vulnerable to cognitive impairment.

The Equivalence and Difference between the English and Chinese Language Versions of the Repeatable Battery for the Assessment of Neuropsychological Status.

OBJECTIVE: Chinese is the most commonly spoken language in the world. The availability of Chinese translations of assessment scales is useful for research in multi-ethnic and multinational studies. This study aimed to establish whether each of the Chinese translations (Mandarin, Hokkien, Teochew, and Cantonese) of the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS) achieved measurement equivalence to the English version. METHOD: Participants included 1856 ethnic Chinese, older adults. The RBANS was administered in the language/dialect according to the participants' preference by interviewers who were fluent in that language/dialect. Multiple regression analysis was used to adjust for demographic and clinical differences between participants who spoke different languages/dialects. Equivalence (practical equivalence) was declared if the 90% confidence interval for the adjusted mean difference fell entirely within the pre-specified equivalence margin, ±.2 (±.4) standard deviations. RESULTS: The delayed memory index was at least practically equivalent across languages. The Mandarin, Hokkien, and Teochew versions of the immediate memory, language, and total scale score were practically equivalent to the English version; the Cantonese version showed small differences from the English version. Equivalence was not established for the Hokkien and Teochew versions of the visuospatial/constructional index. The attention index was different across languages. CONCLUSIONS: Data from the English and Chinese versions for the total scale score, language, delayed, and immediate memory indexes may be pooled for analysis. However, analysis of the attention and visuospatial/constructional indexes from the English and Chinese versions should include a covariate that represents the version in the statistical adjustment.

Resilience, stressful life events, and depressive symptomatology among older Chinese adults.

OBJECTIVE: The association between exposure to stressful life events (SLEs) and late-life depression is well-documented. However, the role of resilience as a buffer against the adverse mental health effects of SLEs in late life has not been convincingly demonstrated. In this paper, the moderating effect of resilience in the relationship between SLEs and depressive symptomatology in older Chinese adults is investigated. METHOD: A population sample of 385 community-dwelling older Chinese adults aged ≥60 years responded to questionnaires on resilience (Connor-Davidson resilience scale), depressive symptomatology (Geriatric Depression Scale, GDS-15) and SLEs. RESULTS: Increased numbers of SLEs (ß = 0.343, p < .001) and lower levels of resilience (ß = -0.137, p < 0.001) were significantly associated with higher levels of depressive symptomatology. There was a significant interaction of resilience and number of SLEs on depressive symptomatology (p = 0.003). The sense of personal competence and optimism was the principal underlying resilience dimension moderating the relationship for both the young-old (aged 60-69) and the old-old (aged 70 and above). CONCLUSION: The finding of significant interaction supported the role of resilience in moderating the adverse effect of SLEs in terms of depressive symptoms among older Chinese adults.

Single versus combination tocolytic regimen in the prevention of preterm births in women: a prospective cohort study.

OBJECTIVE: Our objective is to compare the efficacy of combination regimen (salbutamol and nifedipine) against single regimen (nifedipine alone) in preventing preterm births among women with preterm labor. RESULTS: A total of 76 women with gestational age (GA) ranging from 24+0 to 35+6 weeks, who sought treatment for preterm labor with or without cervical dilatation, were recruited for the prospective cohort study. Of these, 38 (50%) had single tocolytic regimen and 38 (50%) had combination tocolytic regimen. The mean GAs at admission were similar for both groups at 31 weeks (±2.93) for Group 1 and 30.9 weeks (±2.88) for Group 2 (P=0.873). The mean GAs at delivery were 37.8 weeks (±1.98) for the single regimen and 36.2 weeks (±3.26) for the combined regimen (P=0.011). The mean tocolytic to delivery interval for the single regimen was longer at 6.74 weeks (±3.13) as compared with 5.21 weeks (±3.61) for the combination regimen (P<0.05). Those on the combination regimen complained of more adverse effects (P<0.001). CONCLUSION: Our study results suggested that the use of nifedipine as a single tocolytic regimen is as effective as the combination regimen in the delay of preterm births and has much less side effects. Hence, we recommend the sole use of nifedipine for the management of preterm labor.

Normative data for the repeatable battery for the assessment of neuropsychological status in elderly Chinese.

Asia will experience a surge in dementia prevalence within the next 20-40 years, but there is a dearth of well-normed neuropsychological tests that could assist with dementia diagnosis. Here, we report normative data for the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS) in Elderly ethnic Chinese Singaporeans aged 55-91 years of age. A total of 1,165 male and female community-dwelling, cognitively normal elderly Chinese persons in Singapore, with varying levels of education and range of languages, were tested with the RBANS version A. The effects of age, education, language and gender on RBANS performance were examined. Negative effects of increased age and positive effects of education on the RBANS subtests, Index and Total Scale scores were found suggesting differential associations between age-related cognitive decline and education that vary according to the specific cognitive ability measured. The findings indicate that unique cultural and educational profile of elderly Chinese should be considered when applying the RBANS in this population.

Depression and anxiety in Singaporean high-risk pregnancies - prevalence and screening.

OBJECTIVE: Data on psychiatric morbidity in high-risk pregnant Singaporean women are limited. This study aimed to establish the prevalence of antenatal depression and anxiety in high-risk pregnancies, compare the prevalence of antenatal depression in high-risk pregnancies vs. pregnancies of unspecified obstetric risk and examine the Edinburgh Postnatal Depression Scale (EPDS) and State Trait Anxiety Inventory (STAI) as screening tools for these disorders. METHOD: Two hundred high-risk pregnant inpatients at a national public maternity hospital were included. Three psychometric assessment tools were used to evaluate all participants: the diagnostic Mini International Neuropsychiatric Interview and the screening EPDS and STAI. RESULTS: Rates of major depression, minor depression, anxiety disorder (agoraphobia, generalized anxiety disorder, panic disorder), and comorbid depression and anxiety were 11%, 7%, 12.5% and 5%, respectively. Major depression was more prevalent in high-risk pregnancies than in the historical cohort of unspecified obstetric risk (11% versus 4.3%). EPDS (cutoff 8/9) screens well for depression and anxiety in high-risk pregnancies (area under the receiver operating characteristic curve=0.82-0.87). CONCLUSION: Antenatal depression and anxiety are highly prevalent in a sample of high-risk pregnant Singaporean women. EPDS performs well in screening for depression and anxiety in high-risk pregnant women, with further psychiatric assessment recommended for women with score ≥ 9.

Pulmonary function and cognitive decline in an older Chinese population in Singapore.

INTRODUCTION: Various cognitive deficits associated with reduced pulmonary function are reported in different studies, but the pattern of cognitive deficits across multiple domains and its associated everyday functional disability remain unclear. METHODS: We analyzed neuropsychological functioning, cognitive impairment and accompanying disability in instrumental activities of daily living (IADL) associated with reduced pulmonary function in community-living middle-aged and older adults in Singapore. Performance on a comprehensive battery of neuropsychological tests, spirometry and cognitively demanding IADLs were assessed in the population-based Singapore Longitudinal Ageing Studies. RESULTS: Consecutive 10% increase in forced expiratory volume in 1 s (FEV1) as percent of predicted was positively associated with 0.18 points increase in Mini-mental state examination (MMSE) and 0.04 points increase in executive function, independent of age, education and other variables. Subjects with moderate-to-severe airway obstruction showed significantly poorer MMSE score (p for linear trend = 0.001), and information processing speed (p for linear trend < 0.001). FEV1 (per 10% of predicted) was significantly associated with lower risk of cognitive impairment (OR = 0.92, 95% CI: 0.87-0.98, P = 0.005) and cognitive IADL disability (OR = 0.86,95% CI:0.79-0.93, P < 0.001). Pulmonary restriction was associated with greater risk of cognitive impairment (OR = 1.98, 95% CI: 1.26-3.11, P = 0.003) and cognitive IADL disability (OR = 2.43, 95% CI: 1.31-4.53, P = 0.005). Moderate-to-severe airway obstruction (OR = 2.04, 95% CI: 1.11-3.74, P = 0.022) was positively associated with cognitive IADL disability. CONCLUSION: The findings suggest a measurable but modest cognitive effect of low pulmonary function that was accompanied by corresponding disability in living activities. The effect on executive functioning should be further investigated in longitudinal studies.

Changes in depressive symptoms and functional disability among community-dwelling depressive older adults.

BACKGROUND: Previous studies have shown that the presence of depressive symptoms among older persons was evidently associated with subsequent physical and functional decline. However, few studies have directly examined the impact of changes in depressive symptoms or depressed mood on changes in functional ability. The present prospective study examined whether changes in the levels and remission of depressive symptoms were associated with changes in functional ability among community-living older persons who were treated for depressive symptoms in a primary care setting. METHODS: Older persons aged 60 and above with depressive symptoms (N = 267) were followed up in a primary care treatment program over 12 months. Geriatric Depression Scale (GDS-15), and instrumental and basic activities of daily living (IADL and ADL) were measured at baseline and at 12-month follow-up. The associations of GDS change scores and conversion to non-depressed status with ADL and IADL change scores, controlling for baseline covariates including chronic medical comorbidity and Mini-Mental State Examination (MMSE), were examined in multiple regression analyses. RESULTS: An improvement in GDS scores (baseline score minus 12-month score) was significantly associated with improvement (12-month score minus baseline score) in ADL (ß = 0.355, p < 0.001) and IADL scores (ß = 0.165, p = 0.018) after adjusting for baseline functional status, MMSE, chronic medical comorbidities, and other variables. In particular, conversion in GDS status to "non-depressive" state (GDS ≤4) was associated with an improvement in ADL change scores (ß = 0.281, p = 0.019). CONCLUSION: In depressed older persons, an improvement in depressive symptoms was associated with improved functional ability.

Long-term digital mobile phone use and cognitive decline in the elderly.

Research on long-term exposure to electromagnetic fields on cognition is lacking. We investigated the associations between frequent digital mobile phone use and global and domain-specific cognitive changes in older persons, a vulnerable group experiencing age-associated cognitive decline. We assessed 871 non-demented Chinese participants in the Singapore Longitudinal Ageing Studies cohort on the frequency of digital mobile phone use, neurocognitive performance and confounding variables at baseline, and neurocognitive performance at the 4-year follow-up. Findings showed that digital mobile phone users were typically self-selected to possess characteristics favoring better cognitive functioning and concomitantly demonstrate better performance on cognitive tasks. There was evidently no significant deleterious effect of digital mobile phone use on cognitive functioning in older people. Findings suggest, however, that digital mobile phone use may have an independent facilitating effect on global and executive functioning.

Maternal and fetal best interests in day-to-day obstetrics.

In medicine, it is the physician's obligation to promote and protect the patient's interest. In obstetrics, the ethical principles of beneficence and autonomy provide the fundamental framework which guides the management of all pregnant patients. As there is the need for consideration of the fetus, autonomy can become a complex issue giving rise to what is sometimes called "maternal-fetal conflict." In this paper, we aim to discuss some scenarios we encounter in our day-to-day obstetric practice such as pre-eclampsia, fetal growth restriction and labour induction when the best interests of the mother and fetus may be conflicted. We hope to illustrate that logical consideration for maternal and fetal best interests is only possible when there is adequate knowledge to support clinical practice. Certainly, with the rapid availability of newer knowledge and technology, it is the duty of the physician to be educated continuously so as to protect the patient from harm.

Cross-cultural application of the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS): performances of elderly Chinese Singaporeans.

There is a paucity of normative studies outside of North America and on elderly populations with very low education level. In the present study we examined the performance of poorly educated elderly on the Repeatable Battery Assessment of Neuropsychological Status (RBANS) with 352 cognitively normal elderly Chinese persons living in the community in Singapore who were enrolled in the Singapore Longitudinal Ageing Study (SLAS). Those with no formal education performed significantly less well than those with some years of formal education across four of five RBANS indices as well as the Total Scale score. Age- and education-adjusted normative data for the RBANS were established for the sample. The means and standard deviations of each of 12 subtests raw scores, five Index scores and the Total Scale score were calculated and stratified by age and education. Data from the present study should considerably advance the clinical utility of the RBANS in Chinese geriatric evaluations in Singapore, and can serve as a reference source for poorly educated elderly Chinese from around the region and beyond.

Obstetric outcomes of influenza A H1N1 (2009) infection in pregnancy--experience of a Singapore tertiary hospital.

INTRODUCTION: Influenza A H1N1 (2009) pandemic has affected countries worldwide including Singapore. Data on obstetric outcomes of women with H1N1 (2009) in pregnancy are lacking. MATERIALS AND METHODS: This was an observational study analysing the obstetric outcomes of pregnant women with influenza A H1N1 (2009) infection who had delivered at a viable gestation (24 weeks or more) in our centre. RESULTS: Between 23 June 2009 and 30 September 2009, 235 pregnant women were diagnosed with influenza A H1N1 (2009) at our centre, with 42 having delivered and comprising the study cohort. Median age was 27.5 years (range, 16 to 42). Multiparous women comprised 59.5% (25/42) whilst 40.5% (17/42) were primiparous. In terms of ethnicity, 61.9% were Malays, 26.2% Chinese, 4.8% Indians and 7.1% Others. All women received oseltamivir. All had shown recovery from the acute influenza infection. There were no respiratory complications. Twenty-nine women (69.0%) delivered at term. Twenty-fi ve women (59.5%) had spontaneous labour whilst 15 (35.7%) had labour induction. Two women (4.8%) did not labour. Thirty-six women (85.7%) had vaginal delivery, of whom 3 were instrumental deliveries. Apgar scores of greater than 8 at 1 min and 5 min were documented in babies of 95.2% (40/42) women, respectively. Thirty-two women (76.2%) delivered babies with birthweights greater than 2500 g. Compared with historical data from 2008, the H1N1 cohort had comparable mean birthweight and average gestational age at delivery of 38 weeks. CONCLUSION: Our study suggested that obstetric outcomes were not adversely affected by influenza A H1N1 (2009) infection.