Association between an inflammatory biomarker score and future dementia diagnosis in the population-based UK Biobank cohort of 500,000 people.

This study was designed to investigate the relationship between a systematic inflammatory biomarker measure, concurrent and later cognitive performance, and future dementia risk. The literature has reported the potential involvement of inflammation in cognitive performance as well as Alzheimer's Disease, but not consistently. We used a population-based cohort of 500,000 people in the UK and assessed the association between a composite inflammatory biomarker and cognitive performance measures across five domains measured concurrently and 4-13 years later, taking advantage of the large sample size. We also assessed the same biomarker's association with dementia diagnosis 3-11 years later in the initially dementia-free sample. We report small but significant associations between elevated biomarker levels and worsened cognitive performance at baseline for four cognitive tasks (OR = 1.204, p<0.001 for Prospective memory, ß = -0.366, p<0.001 for Fluid intelligence, ß = 8.819, p<0.001 for Reaction time, and ß = -0.224, p<0.001 for Numeric memory), comparing the highest quartile of the biomarker to the lowest. We also found that for one measure (Pairs matching) higher biomarker levels were associated with fewer errors, i.e. better performance (ß = -0.096, p<0.001). We also report that the 4th quartiles of the baseline biomarker levels were significantly associated with cognitive task scores assessed years later on the p< = 0.002 level, except for the Pair matching test, for which none of the quartiles remained a significant predictor. Finally, the highest biomarker quartile was significantly associated with increased dementia risk compared to the lowest quartile (HR = 1.349, p<0.001). A case-only analysis to assess disease subtype heterogeneity suggested probable differences in the association with the highest biomarker quartile between vascular dementia and Alzheimer disease subtypes (OR = 1.483, p = 0.055). Our results indicate that systemic inflammation may play a small but significant part in dementia pathophysiology, especially in vascular dementia.

Where next for understanding race/ethnic inequalities in severe mental illness? Structural, interpersonal and institutional racism.

In this article we use the example of race/ethnic inequalities in severe mental illness to demonstrate the utility of a novel integrative approach to theorising the role of racism in generating inequality. Ethnic minority people in the UK are at much greater risk than White British people of being diagnosed with a severe - psychosis related - mental illness, and this is particularly the case for those with Black Caribbean or Black African origins. There is entrenched dispute about how we might understand the drivers of this inequality. To address this dispute we build on, and to a certain extent refine, established approaches to theorising structural and institutional racism, and integrate this within a theoretical framework that also incorporates racist/discriminatory interactions (interpersonal racism). We argue that this provides a conceptually robust and thorough analysis of the role of inter-related dimensions of racism in shaping risks of severe mental illness, access to care, and policy and practice responses. This analysis carries implications for a broader, but integrated, understanding of the fundamental drives of race/ethnic inequalities in health and for an anti-racism public health agenda.

Frailty Index associates with GRIN2B in two representative samples from the United States and the United Kingdom.

The concept of frailty has been used in the clinical and research field for more than two decades. It is usually described as a clinical state of heightened vulnerability to poor resolution of homeostasis after a stressor event, which thereby increases the risk of adverse outcomes, including falls, delirium, disability and mortality. Here we report the results of the first genome-wide association scan and comparative gene ontology analyses where we aimed to identify genes and pathways associated with the deficit model of frailty. We used a discovery-replication design with two independent, nationally representative samples of older adults. The square-root transformed Frailty Index (FI) was the outcome variable, and age and sex were included as covariates. We report one hit exceeding genome-wide significance: the rs6765037 A allele was significantly associated with a decrease in the square-root transformed FI score in the Discovery sample (beta = -0.01958, p = 2.14E-08), without confirmation in the Replication sample. We also report a nominal replication: the rs7134291 A allele was significantly associated with a decrease in the square-root transformed FI score (Discovery sample: beta = -0.01021, p = 1.85E-06, Replication sample: beta = -0.005013, p = 0.03433). These hits represent the KBTBD12 and the GRIN2B genes, respectively. Comparative gene ontology analysis identified the pathways 'Neuropathic pain signalling in dorsal horn neurons' and the 'GPCR-Mediated Nutrient Sensing in Enteroendocrine Cells', exceeding the p = 0.01 significance in both samples, although this result does not survive correction for multiple testing. Considering the crucial role of GRIN2B in brain development, synaptic plasticity and cognition, this gene appears to be a potential candidate to play a role in frailty. In conclusion, we conducted genome-wide association scan and pathway analyses and have identified genes and pathways with potential roles in frailty. However, frailty is a complex condition. Therefore, further research is required to confirm our results and more thoroughly identify relevant biological mechanisms.

Genome-wide scan of depressive symptomatology in two representative cohorts in the United States and the United Kingdom.

Unlike the diagnosed Major Depressive Disorder, depressive symptomatology in the general population has received less attention in genome-wide association scan (GWAS) studies. Here we report a GWAS study on depressive symptomatology using a discovery-replication design and the following approaches: To improve the robustness of the phenotypic measure, we used longitudinal data and calculated mean scores for at least 3 observations for each individual. To maximize replicability, we used nearly identical genotyping platforms and identically constructed phenotypic measures in both the Discovery and Replication samples. We report one genome-wide significant hit; rs58682566 in the EPG5 gene was associated (p = 3.25E-08) with the mean of the depression symptom in the Discovery sample, without confirmation in the Replication sample. We also report 4 hits exceeding the genome-wide suggestive significance level with nominal replications. Rs11774887, rs4147527 and rs1379328, close to the SAMD12 gene, were associated with the mean depression symptom score (P-values in Discovery sample: 4.58E-06, 7.65E-06 and 7.66E-06; Replication sample: 0.049, 0.029 and 0.030, respectively). Rs13250896, located in an intergenic region, was associated with the mean score of the three somatic items of the depression symptoms score (p = 3.31E-07 and 0.042 for the Discovery and Replication samples). These results were not supported by evidence in the literature. We conclude that despite the strengths of our approach, using robust phenotypic measures and samples that maximize replicability potential, this study does not provide compelling evidence of a single genetic variant's significant role in depressive symptomatology.

Pathways to Well-Being in Later Life: Socioeconomic and Health Determinants Across the Life Course of Australian Baby Boomers.

In many countries like Australia and the United States, baby boomers are referred to as the 'lucky cohort', yet there has been little research on the origins and extent of inequalities within this cohort. This study uses path analysis to investigate direct and indirect effects of childhood and adult socioeconomic status and health on two subjective well-being measures: quality of life and life satisfaction. Retrospective life course data were obtained for 1,261 people aged 60 to 64 in the 2011-12 Life Histories and Health survey, a sub-study of the Australian 45 and Up Study. Supporting an accumulation model, the number of negative childhood and adult exposures were inversely related to both types of well-being. Consistent with a critical period model, childhood exposures had small but significant effects on subjective well-being and were relatively more important for quality of life than for life satisfaction. However, these childhood effects were largely indirect and significantly mediated by more proximal adult exposures, providing support for a pathway model. A key implication of this research is that the critical period for later life well-being is significant in adulthood rather than childhood, suggesting that there may be key opportunities for improving individuals' later life well-being far beyond the early, formative years. This research highlights the importance of understanding how earlier life exposures impact experiences in later life, and investing in health and socioeconomic opportunities to reduce inequalities across all stages of life.

Proinflammatory genotype is associated with the frailty phenotype in the English Longitudinal Study of Ageing.

BACKGROUND: Frailty is a state of increased vulnerability to poor resolution of homeostasis after a stressor event, which increases the risk of adverse outcomes including falls, disability and death. The underlying pathophysiological pathways of frailty are not known but the hypothalamic-pituitary-adrenal axis and heightened chronic systemic inflammation appear to be major contributors. METHODS: We used the English Longitudinal Study of Ageing dataset of 3160 individuals over the age of 50 and assessed their frailty status according to the Fried-criteria. We selected single nucleotide polymorphisms in genes involved in the steroid hormone or inflammatory pathways and performed linear association analysis using age and sex as covariates. To support the biological plausibility of any genetic associations, we selected biomarker levels for further analyses to act as potential endophenotypes of our chosen genetic loci. RESULTS: The strongest association with frailty was observed in the Tumor Necrosis Factor (TNF) (rs1800629, P = 0.001198, ß = 0.0894) and the Protein Tyrosine Phosphatase, Receptor type, J (PTPRJ) (rs1566729, P = 0.001372, ß = 0.09397) genes. Rs1800629 was significantly associated with decreased levels of high-density lipoprotein (HDL) (P = 0.00949) and cholesterol levels (P = 0.00315), whereas rs1566729 was associated with increased levels of HDL (P = 0.01943). After correcting for multiple testing none of the associations remained significant. CONCLUSIONS: We provide potential evidence for the involvement of a multifunctional proinflammatory cytokine gene (TNF) in the frailty phenotype. The implication of this gene is further supported by association with the endophenotype biomarker results.

Ethnic differences in cognitive development in the first 7†years: does maternal generational status matter?

BACKGROUND: Differences in cognitive development have been observed across a variety of ethnic minority groups but relatively little is known about the persistence of these developmental inequalities over time or generations. METHODS: A repeat cross-sectional analysis assessed cognitive ability scores of children aged 3, 5 and 7 years from the longitudinal UK Millennium Cohort Study (white UK born n=7630; Indian n=248; Pakistani n=328; Bangladeshi n=87; black Caribbean n=172; and black African n=136). Linear regression estimated ethnic differences in age normed scores at each time point. Multivariable logistic regression estimated within-group generational differences in test scores at each age adjusting stepwise for sociodemographic factors, maternal health behaviours, indicators of the home learning environment and parenting styles. RESULTS: The majority of ethnic minority groups scored lower than the white UK born reference group at 3 years with these differences narrowing incrementally at ages 5 and 7 years. However, the black Caribbean group scored significantly lower than the white UK born reference group throughout early childhood. At 3 years, Pakistani, black Caribbean and black African children with UK born mothers had significantly higher test scores than those with foreign born mothers after baseline adjustment for maternal age and child gender. Controlling for social, behavioural and parenting factors attenuated this generational advantage. By 7 years there were no significant generational differences in baseline models. CONCLUSIONS: Ethnic differences in cognitive development diminish throughout childhood for the majority of groups. Cumulative exposure to the UK environment may be associated with higher cognitive development scores.

Patterns and causes of health inequalities in later life: a Bourdieusian approach.

This study explores the relationship between social class and health change in older people in a path analysis, using data from the English Longitudinal Study of Ageing (n = 6241) in a Bourdieusian theoretical framework. Bourdieu drew a distinction between the occupational characteristics by which people are classified and the secondary properties of class that relate to lifestyle (economic, cultural and social capitals). Our path model includes both occupational and secondary characteristics of objective social class as well as a measure of subjective social class. We investigate the effects of the predictors on change in three health outcomes (self-rated health, number of symptoms of depression and number of difficulties with the activities of daily living). The analysis adds to Bourdieusian research by showing how the effects of objective social class on health are partially mediated by perceived social status. It also adds to substantive research on the relationship between class and health by suggesting that class-related health inequalities do persist for older people, even for those who are not in paid employment. It suggests that a large amount of the effect of occupation on the health of older people is not direct but indirect; through their personal wealth and lifestyle.

Adapting data collection methods in the Australian Life Histories and Health Survey: a retrospective life course study.

OBJECTIVE: Ideally, life course data are collected prospectively through an ongoing longitudinal study. We report adaptive multimethod fieldwork procedures that gathered life history data by mail survey and telephone interview, comparable with the face-to-face methods employed in the English Longitudinal Study on Ageing (ELSA). DESIGN: The Australian Life Histories and Health (LHH) Survey was a substudy of the Australian 45 and Up Study, with data collection methods modified from the ELSA Study. A self-complete questionnaire and life history calendar were completed by the participants, followed by a computer-assisted telephone interview recording key life events. RESULTS: The LHH survey developed and tested procedures and instruments that gathered rich life history data within an ongoing Australian longitudinal survey on ageing. Data collection proved to be economical. The use of a self-complete questionnaire in conjunction with a life history calendar and coordinated computer-assisted telephone interview was successful in collecting retrospective life course information, in terms of being thorough, practical and efficient. This study has a diverse collection of data covering the life course, starting with early life experiences and continuing with socioeconomic and health exposures and outcomes during adult life. CONCLUSIONS: Mail and telephone methodology can accurately and economically add a life history dimension to an ongoing longitudinal survey. The method is particularly valuable for surveying widely dispersed populations. The results will facilitate understanding of the social determinants of health by gathering data on earlier life exposures as well as comparative data across geographical and societal contexts.

Facilitators and barriers to help-seeking for breast and cervical cancer symptoms: a qualitative study with an ethnically diverse sample in London.

OBJECTIVE: Earlier diagnosis of cancer has become a policy priority. There is evidence that minority ethnic groups are more likely to delay help-seeking for cancer symptoms, but few studies have explored reasons for delay in these groups. The present study explored facilitators and barriers to help-seeking for breast and cervical cancer in an ethnically diverse sample of women. METHODS: Semi-structured interviews were carried out with 54 healthy women from a range of ethnic backgrounds; Indian, Pakistani, Bangladeshi, Caribbean, African, Black British, Black other, White British and White other. Framework analysis was used to identify themes. RESULTS: Appraising a symptom as possibly due to cancer was an important facilitator of help-seeking, although for some the prospect of a cancer diagnosis was a deterrent. Women believed that earlier diagnosis improved the chance of survival, and this facilitated prompt help-seeking. A sympathetic GP facilitated help-seeking, and an unsympathetic GP was a deterrent. Some ethnic minority women described the use of alternative medicine and prayer as a first-line strategy that might delay help-seeking. Language barriers, racism and a tendency to 'soldier on' were also mentioned by these women. CONCLUSIONS: Models of delay in presentation for early cancer symptoms are likely to transfer across different ethnic groups. Encouraging open discussion about cancer among minority communities could help raise awareness about the importance of early detection and promote help-seeking as a priority response to a possible cancer symptom.

Impact of ethnic density on adult mental disorders: narrative review.

BACKGROUND: The 'ethnic density hypothesis' is a proposition that members of ethnic minority groups may have better mental health when they live in areas with higher proportions of people of the same ethnicity. Investigations into this hypothesis have resulted in a complex and sometimes disparate literature. AIMS: To systematically identify relevant studies, summarise their findings and discuss potential explanations of the associations found between ethnic density and mental disorders. METHOD: A narrative review of studies published up to January 2011, identified through a systematic search strategy. Studies included have a defined ethnic minority sample; some measure of ethnic density defined at a geographical scale smaller than a nation or a US state; and a measure ascertaining mental health or disorder. RESULTS: A total of 34 papers from 29 data-sets were identified. Protective associations between ethnic density and diagnosis of mental disorders were most consistent in older US ecological studies of admission rates. Among more recent multilevel studies, there was some evidence of ethnic density being protective against depression and anxiety for African American people and Hispanic adults in the USA. However, Hispanic, Asian-American and Canadian 'visible minority' adolescents have higher levels of depression at higher ethnic densities. Studies in the UK showed mixed results, with evidence for protective associations most consistent for psychoses. CONCLUSIONS: The most consistent associations with ethnic density are found for psychoses. Ethnic density may also protect against other mental disorders, but presently, as most studies of ethnic density have limited statistical power, and given the heterogeneity of their study designs, our conclusions can only be tentative.

The effects of acculturation on obesity rates in ethnic minorities in England: evidence from the Health Survey for England.

OBJECTIVES: To investigate the extent of generational differences in adult health-related lifestyles and socio-economic circumstances, and explore whether these differences might explain changing patterns of obesity in ethnic minorities in England. METHODS: Seven ethnic minority groups were selected from the ethnically boosted 1999 and 2004 Health Survey for England (Indian n = 1580; Pakistani n = 1858; Bangladeshi n = 1549; Black Caribbean n = 1472; Black African n = 587; Chinese n = 1559; and Irish n = 889). Age and sex adjusted odds of being obese in the second generation when compared with the first were estimated before and after adjusting for generational differences in health-related behaviours (snacking, eating cakes and fried foods, low levels of physical exercise, any drinking, current smoker, etc.) and socio-economic factors (social class, equivalized income and highest qualification). RESULTS: Indian [OR: 1.76 (1.14-2.71)] and Chinese [OR: 3.65 (1.37-9.78)] groups were more likely to be obese in the second generation than the first after adjusting for age and sex, with no significant differences observed in all other groups. However, the risk of obesity in all groups converged between generations to the risk observed in the White reference group, with exception to the Black Caribbean group. Adjusting independently for the mixed patterns of acculturative changes and the uniform upward social mobility in all groups increased the risk of obesity in the second generation. CONCLUSIONS: Obesity converged to the risk in the majority population following acculturation. Future research needs to consider generation and trans-cultural identities as a fundamental variable in determining the causes of ethnic health inequalities.

Subgroup differences in psychosocial factors relating to coronary heart disease in the UK South Asian population.

OBJECTIVES: To explore the differences in psychosocial risk factors related to coronary heart disease (CHD) between South Asian subgroups in the UK. South Asian people suffer significantly higher rates of CHD than other ethnic groups, but vulnerability varies between South Asian subgroups, in terms of both CHD rates and risk profiles. Psychosocial factors may contribute to the excess CHD propensity that is observed; however, subgroup heterogeneity in psychosocial disadvantage has not previously been systematically explored. METHODS: With a cross-sectional design, 1065 healthy South Asian and 818 white men and women from West London, UK, completed psychosocial questionnaires. Psychosocial profiles were compared between South Asian religious groups and the white sample, using analyses of covariance and post hoc tests. RESULTS: Of the South Asian sample, 50.5% was Sikh, 28.0% was Hindu, and 15.8% was Muslim. Muslim participants were more socioeconomically deprived and experienced higher levels of chronic stress, including financial strain, low social cohesion, and racial discrimination, compared with other South Asian religious groups. In terms of health behaviors, Muslim men smoked more than Sikhs and Hindus, and Muslims also reported lower alcohol consumption and were less physically active than other groups. CONCLUSION: This study found that Muslims were exposed to more psychosocial and behavioral adversity than Sikhs and Hindus, and highlights the importance of investigating subgroup heterogeneity in South Asian CHD risk.

Religious and ethnic differences in health: evidence from the Health Surveys for England 1999 and 2004.

OBJECTIVES: To examine the role of religion in the patterning of health inequities, and how this is related to ethnicity and socioeconomic status. DESIGN: Multivariate analyses using nationally representative data on self-assessed fair or poor health, longstanding limiting illness, diagnosed diabetes, diagnosed hypertension, waist-hip ratio, body mass index, current tobacco use and participating in no regular physical activity from 14,924 Christians, 4337 Muslims, 656 Sikhs, 1197 Hindus and 2682 people reporting not identifying with any religion with different ethnic backgrounds, who were interviewed as part of the Health Survey for England in either 1999 or 2004, adjusted for age, gender and socioeconomic status and periodicity. RESULTS: Odds ratios for general health, hypertension, diabetes, waist-hip ratio, tobacco use and physical activity speak to the importance of ethnicity in the patterning of health inequalities. But there is also evidence of an important, independent role for religion, with risks for the different health indicators varying between people with the same ethnic, but different religious, identifications. Adjusting for socioeconomic status attenuated the ethnic/religious patterning of, particularly, self-assessed health, longstanding activity-limiting illness, waist-hip ratio, body mass index and tobacco use. CONCLUSIONS: This evidence enables greater understanding of the complexities of the relationship between ethnicity, religion and health, recognising the need to understand the heterogeneity underlying both ethnic and religious group membership and the processes producing the structural disadvantage facing certain religious and ethnic groups in the mediation of the relationship between health and ethnicity/religion.

Ethnic variation in childhood asthma and wheezing illnesses: findings from the Millennium Cohort Study.

BACKGROUND: It is not clear how respiratory morbidity during early childhood varies across ethnic groups in the UK. This article seeks to determine whether asthma and wheeze illnesses during early childhood differ across ethnic groups and what factors explain observed differences. METHODS: Data from the UK Millennium Cohort Study on 14,630 children were analyzed from the second sweep of interviews. Parental interviews were conducted when the cohort member was aged approximately 3(1/2) years. Data collected included the occurrence of asthma and wheezing symptoms, biological and socio-economic factors and markers of cultural tradition. RESULTS: At age 3, 12.3% (n = 1,902) of children had ever had asthma and 20.0% (n = 3,030) had wheezed in the last 12 months. 18.2% of Black Caribbean children and 5.0% of Bangladeshi children reported ever asthma compared with 11.6% of White children. 25.5% of Black Caribbean children and 8.7% of Bangladeshi reported recent wheeze compared with 19.4% of White children. After adjustments, the disadvantage in asthma and recent wheeze for Black Caribbeans was mostly explained by socio-economic factors (adjusted odds ratios (OR) for asthma 1.42, 95% confidence interval (CI) 0.96-2.09; recent wheeze 1.18, 0.85-1.64). The Bangladeshi advantage lost statistical significance, mostly due to adjustment for markers of cultural tradition (adjusted OR for asthma 0.40, 95% CI 0.15-1.09; recent wheeze 0.44, 0.18-1.19). CONCLUSION: Our results point to the need to locate child health within the unique context of each ethnic group and to recognize that potential explanations for observed differences do not necessarily hold for all groups.

Racial/ethnic differences in breastfeeding initiation and continuation in the United kingdom and comparison with findings in the United States.

OBJECTIVE: Patterns of breastfeeding vary considerably across different racial/ethnic groups; however, little is known about factors that might explain differences across and within different racial/ethnic groups. Here we examine patterns of breastfeeding initiation and continuation among a racially/ethnically diverse sample of new mothers and compare this with patterns seen in the United States. The effects of demographic, social, economic, and cultural factors on racial/ethnic differences in breastfeeding practices are assessed. METHODS: The sample includes all singleton infants whose mothers participated in the first survey of the United Kingdom Millennium Cohort Study. Missing data reduced the sample to 17,474 (96%) infants with complete data. RESULTS: After adjustment for demographic, economic, and psychosocial factors, logistic regression models showed that Indian, Pakistani, Bangladeshi, black Caribbean, and black African mothers were more likely to initiate breastfeeding compared with white mothers. Further adjustment for a marker of cultural tradition attenuated these relationships, but all remained statistically significant, suggesting that some of the difference was a consequence of cultural factors. After adjustment for demographic, economic, and psychosocial factors, Indian, Pakistani, Bangladeshi, black Caribbean, and black African mothers were more likely to continue breastfeeding at 3 months compared with white mothers. Additional adjustment for a marker of cultural tradition attenuated the relationship for Indian, Pakistani, Bangladeshi, and black African mothers, but all remained statistically significant. Models run for breastfeeding continuation at 4 and 6 months were consistent with these results. CONCLUSIONS: We have shown that in the United Kingdom the highest breastfeeding rates are among black and Asian mothers, which is in stark contrast to patterns in the United States, where the lowest rate is seen among non-Hispanic black mothers. The contrasting racial/ethnic patterns of breastfeeding in the United Kingdom and United States necessitate very different public health approaches to reach national targets on breastfeeding and reduce health disparities. Those who implement future policies aimed at increasing breastfeeding rates need to pay attention to different social, economic, and cultural profiles of all racial/ethnic groups.

Racism, psychosis and common mental disorder among ethnic minority groups in England.

BACKGROUND: The aim of this study was to explore the relationship between risk of psychosis, common mental disorder (CMD) and indicators of racism among ethnic minority groups in England and how this relationship may vary by particular ethnic groups. METHOD: A multivariate analysis was carried out of quantitative, cross-sectional data from a nationally representative community sample of people aged between 16 and 74 years from the largest ethnic minority groups in England: those of Caribbean, Indian, Pakistani, Bangladeshi and Irish origin. RESULTS: Experience of interpersonal racism and perceiving racism in the wider society each have independent effects on the risk of CMD and psychosis, after controlling for the effects of gender, age and socio-economic status. There was some variation in the findings when they were conducted for separate ethnic and gender groups. CONCLUSIONS: An understanding of the relationship between racism and mental health may go some way towards explaining the ethnic variations found in both CMD and, particularly, psychosis.

The structuring of ethnic inequalities in health: economic position, racial discrimination, and racism.

Differences in health across ethnic groups have been documented in the United States and the United Kingdom. The extent to which socioeconomic inequalities underlie such differences remains contested, with many instead focusing on cultural or genetic explanations. In both the United States and the United Kingdom, data limitations have greatly hampered investigations of ethnic inequalities in health. Perhaps foremost of these is the inadequate measurement of ethnicity, but also important is the lack of good data on socioeconomic position, particularly data that address life-course issues. Other elements of social disadvantage, particularly experiences of racism, are also neglected. The author reviews existing evidence and presents new evidence to suggest that social and economic inequalities, underpinned by racism, are fundamental causes of ethnic inequalities in health.

Ethnicity, environment and health: putting ethnic inequalities in health in their place.

We set out to explore the influence of environment on ethnic inequalities in health. Studies exploring the relationship between environment and health have tended to ignore the role of ethnicity, and the health impact of the residential concentration of ethnic minority groups in disadvantaged areas. Those that have explored the role of ethnicity tend to focus on the way in which residential concentration may promote a sense of community among ethnic minority groups, and, consequently, may be protective of health (the 'ethnic density effect'). Again, they have tended to ignore the health impact of the concentration of ethnic minority groups in areas of social and economic disadvantage. We undertook a factor analysis to determine aspects of perception of 'quality' of the local environment, followed by multi-level analyses to explore the relationship between self-reported fair or poor health and individual- and ward-level characteristics among four ethnic groups (Caribbean, Indian, Pakistani and Bangladeshi, and white) in the UK. Results of the factor analysis suggested three underlying dimensions of perception of quality of the local area, related to the quality of the local environment, the provision of local amenities and local problems of crime and nuisance. These factors were entered into the multi-level models at level 2, along with indicators of ward-level ethnic density and Townsend's deprivation score, with age, gender and household social class entered at level 1. In general, there was a residual random ward-level effect suggesting an area influence on self-assessed health. However, on the whole, none of the ward-level indicators showed any statistically significant association with self-assessed health, making it difficult to precisely determine the mechanisms operating. These findings suggest, though, that there is no ethnic density effect on self-assessed health for ethnic minority groups.