Ellena Badrick

Work stress and coronary heart disease: what are the mechanisms?

AIMSnTo determine the biological and behavioural factors linking work stress with coronary heart disease (CHD).nnnMETHODS AND RESULTSnA total of 10 308 London-based male and female civil servants aged 35-55 at phase 1 (1985-88) of the Whitehall II study were studied. Exposures included work stress (assessed at phases 1 and 2), and outcomes included behavioural risk factors (phase 3), the metabolic syndrome (phase 3), heart rate variability, morning rise in cortisol (phase 7), and incident CHD (phases 2-7) on the basis of CHD death, non-fatal myocardial infarction, or definite angina. Chronic work stress was associated with CHD and this association was stronger among participants aged under 50 (RR 1.68, 95% CI 1.17-2.42). There were similar associations between work stress and low physical activity, poor diet, the metabolic syndrome, its components, and lower heart rate variability. Cross-sectionally, work stress was associated with a higher morning rise in cortisol. Around 32% of the effect of work stress on CHD was attributable to its effect on health behaviours and the metabolic syndrome.nnnCONCLUSIONnWork stress may be an important determinant of CHD among working-age populations, which is mediated through indirect effects on health behaviours and direct effects on neuroendocrine stress pathways.

Self-Reported Sleep Duration and Sleep Disturbance Are Independently Associated with Cortisol Secretion in the Whitehall II Study

CONTEXTnThe association of short sleep duration with cortisol secretion has not been thoroughly examined in large community dwelling populations and the relative importance of short sleep duration and sleep disturbance is unclear.nnnOBJECTIVEnThe objective of the study was to assess the relationships between self-reported sleep duration, sleep disturbance, and salivary cortisol secretion.nnnDESIGNnThis was a cross-sectional analysis using data from phase 7 (2002-2004) of the Whitehall II study. Sleep disturbances were assessed using a modified version of the Jenkins Scale.nnnSETTINGnThe occupational cohort was originally recruited in 1985-1989.nnnPARTICIPANTSnAnalyses included 2751 participants with complete cortisol measures and who collected their first sample within 15 min of waking, were not on medication affecting cortisol secretion, and had complete information for all covariates.nnnOUTCOME MEASUREnSix saliva samples were taken on waking, waking + 0.5, 2.5, 8, and 12 h and bedtime for the assessment of the cortisol awakening response and the slope in cortisol secretion across the day.nnnRESULTSnIn mutually adjusted analyses, both sleep duration and disturbances were independently associated with a flatter diurnal slope in cortisol secretion, such that evening cortisol secretion was raised in those reporting short sleep duration and high sleep disturbance. Short sleep duration was also associated with the cortisol awakening response. These effects were independent of a number of covariates, including waking time on day of sampling and stress on the day of cortisol assessment.nnnCONCLUSIONnShort sleep duration and increased sleep disturbances are independently associated with diurnal slope in cortisol secretion of a large community-based cohort of middle-aged men and women.

Psychological coping styles and cortisol over the day in healthy older adults.

Patterns of psychological coping are associated with a variety of health outcomes but the underlying pathways are not yet established. The purpose of this study was to assess the relationship between salivary cortisol output over the course of a day and coping style. Data were available from 350 men and 192 women with an average age of 60.9 years. Participants were drawn from the Whitehall II cohort, and had no history of cardiovascular disease. Individuals who were taking medication that might affect cortisol levels were also excluded. Saliva samples were provided on waking, then 0.5, 2.5, 8 and 12h after waking, and just before the participant went to sleep. Coping style was measured with a standard instrument, the COPE, and data were factor analysed to generate three factors: seeking social support, problem engagement and problem avoidance. The relationships between these factors and the cortisol awakening response (CAR), the slope of cortisol change over the day and total cortisol output over the day (excluding the waking period) were assessed using multiple linear regression. Cortisol output over the day was inversely associated with coping with stress by seeking social support (p=0.034) and by problem engagement (p=0.003), independently of age, gender, body mass index, smoking, depression, self-rated health, time of waking and income. Individuals who coped by problem engagement and seeking support had lower cortisol levels. Additionally, gender, BMI, smoking, self-rated health and time of waking were independently related to cortisol output over the day. There were no significant associations between coping and the CAR or cortisol slope over the day. The results indicate that adaptive coping styles are related to low levels of cortisol over the day, suggesting that neuroendocrine pathways may partly mediate relationships between psychological coping and health.

Cortisol secretion and fatigue: associations in a community based cohort.

The association between fatigue and reduced activity in the hypothalamo-pituitary-adrenal (HPA) axis has been described. However the temporal association between fatigue and HPA activity is under debate. We examine whether alterations in cortisol secretion play a role in the development of fatigue or whether changes occur later as a consequence of fatigue in a longitudinal cohort study of 4299 community dwelling adults (mean age 61). Cortisol secretion was measured from saliva samples collected waking, waking + 0.5, 2.5, 8, 12 h and bedtime at phase 7 (2003-2004) of the Whitehall II study. Fatigue was measured at phase 6 (2001), phase 7 and phase 8 (2006) of the Whitehall II study. Three elements of secretion were examined: waking cortisol, the cortisol awakening response and diurnal slope in cortisol secretion. Fatigue was determined using the vitality sub-scale of the Short Form-36. A wide variety of co-variates were measured. We find that fatigue measured at phase 6 was not associated with cortisol secretion at phase 7. At phase 7, low waking cortisol levels and a flat slope in diurnal cortisol secretion were associated with fatigue independently of co-variates. In participants low or free of fatigue at phase 7 low waking cortisol and flatter slope in cortisol secretion were associated with new-onset fatigue at phase 8 (for example, odds ratio for lowest vs. highest tertile of waking cortisol 1.50; 95% confidence intervals, 1.08, 2.09 after adjusting for all co-variates). In conclusion, we find that low waking salivary cortisol and a flat slope in cortisol secretion is associated with fatigue. Cortisol is also associated with future onset of fatigue suggesting that changes in cortisol secretion are etiologic or occur early in the genesis of fatigue.

Identifying patterns in cortisol secretion in an older population. Findings from the Whitehall II study

Alterations in the patterning of diurnal cortisol secretion are associated with poor health in clinical populations with flat patterns a particular risk. Flatter patterns in cortisol secretion may reflect impaired negative feedback in the hypothalamic-pituitary-adrenal axis. The correlates of discrete clusters of patterns in the diurnal secretion of cortisol have not been well described in large community dwelling populations. We describe discrete clusters of patterns of cortisol secretion and examine the correlates of these patterns using a latent variable mixture modelling approach. Analyses use data from 2802 participants with complete information on cortisol secretion, age, walking/gait speed, stress, waking up time and sleep duration. Cortisol was assessed from six saliva samples collected at waking, waking plus 30 min, 2.5h, 8h, 12h and bedtime. We find two patterns (curves) of diurnal cortisol secretion. These curves are described as normative [prevalence 73%] and a raised [27%] curve differentiated by a lower cortisol awakening response in the normative group, a higher diurnal cortisol and flatter pattern of release in the raised group. Older age, being male, a smoker, stress on the day of sampling, slower walking speed and shorter sleep duration increased the odds of being in the raised curve, relative to the normative curve. In conclusion, two patterns of cortisol secretion occur in middle aged men and women. Raised pattern of secretion, which occurs in 27% of our participants is associated with demographic variables, adverse health behaviours, psychosocial environment and impaired physical functioning.

Cardiovascular multimorbidity: the effect of ethnicity on prevalence and risk factor management

BACKGROUNDnMultimorbidity is common in primary care populations. Within cardiovascular disease, important differences in disease prevalence and risk factor management by ethnicity are recognised.nnnAIMnTo examine the population burden of cardiovascular multimorbidity and the management of modifiable risk factors by ethnicity.nnnDESIGN AND SETTINGnCross-sectional study of general practices (148/151) in the east London primary care trusts of Tower Hamlets, City and Hackney, and Newham, with a total population size of 843 720.nnnMETHODnUsing MIQUEST, patient data were extracted from five cardiovascular registers. Logistic regression analysis was used to examine the risk of being multimorbid by ethnic group, and the control of risk factors by ethnicity and burden of cardiovascular multimorbidity.nnnRESULTSnThe crude prevalence of cardiovascular multimorbidity among patients with at least one cardiovascular condition was 34%. People of non-white ethnicity are more likely to be multimorbid than groups of white ethnicity, with adjusted odds ratios of 2.04 (95% confidence interval [CI] = 1.94 to 2.15) for South Asians and 1.23 (95% CI = 1.18 to 1.29) for groups of black ethnicity. Achievement of targets for blood pressure, cholesterol, and glycated haemoglobin (HbA(1c)) was higher for patients who were multimorbid than unimorbid. For cholesterol and blood pressure, South Asian patients achieved better control than those of white and black ethnicity. For HbA(1c) levels, patients of white ethnicity had an advantage over other groups as the morbidity burden increased.nnnCONCLUSIONnThe burden of multiple disease varies by ethnicity. Risk factor management improves with increasing levels of cardiovascular multimorbidity, but clinically important differences by ethnicity remain and contribute to health inequalities.

Ethnic and social disparity in glycaemic control in type 2 diabetes; cohort study in general practice 2004-9.

Objective To determine whether ethnic group differences in glycated haemoglobin (HbA1c) changed over a 5-year period in people on medication for type 2 diabetes. Design Open cohort in 2004–9. Setting Electronic records of 100 of the 101 general practices in two inner London boroughs. Participants People aged 35 to 74 years on medication for type 2 diabetes. Main outcome measures Mean HbA1c and proportion with HbA1c controlled to ≤7.5%. Results In this cohort of 24,111 people, 22% were White, 58% South Asian and 17% Black African/Caribbean. From 2004 to 2009 mean HbA1c improved from 8.2% to 7.8% for White, from 8.5% to 8.0% for Black African/Caribbean and from 8.5% to 8.0% for South Asian people. The proportion with HbA1c controlled to 7.5% or less, increased from 44% to 56% in White, 38% to 53% in Black African/Caribbean and 34% to 48% in South Asian people. Ethnic group and social deprivation were independently associated with HbA1c. South Asian and Black African/Caribbean people were treated more intensively than White people. Conclusion HbA1c control improved for all ethnic groups between 2004–9. However, South Asian and Black African/Caribbean people had persistently worse control despite more intensive treatment and significantly more improvement than White people. Higher social deprivation was independently associated with worse control.

The relationship of ethnicity to the prevalence and management of hypertension and associated chronic kidney disease.

BackgroundThe effect of ethnicity on the prevalence and management of hypertension and associated chronic kidney (CKD) disease in the UK is unknown.MethodsWe performed a cross sectional study of 49,203 adults with hypertension to establish the prevalence and management of hypertension and associated CKD by ethnicity. Routinely collected data from general practice hypertension registers in 148 practices in London between 1/1/07 and 31/3/08 were analysed.ResultsThe crude prevalence of hypertension was 9.5%, and by ethnicity was 8.2% for White, 11.3% for South Asian and 11.1% for Black groups. The prevalence of CKD stages 3-5 among those with hypertension was 22%. Stage 3 CKD was less prevalent in South Asian groups (OR 0.77, 95% CI 0.67 - 0.88) compared to Whites (reference population) with Black groups having similar rates to Whites. The prevalence of severe CKD (stages 4-5) was higher in the South Asian group (OR 1.53, 95% CI 1.17 - 2.0) compared to Whites, but did not differ between Black and White groups. In the whole hypertension cohort, achievement of target blood pressure (< 140/90 mmHg) was better in South Asian (OR 1.43, 95% CI 1.28 - 1.60) and worse in Black groups (OR 0.79, 95% CI 0.74 - 0.84) compared to White patients. Hypertensive medication was prescribed unequally among ethnic groups for any degree of blood pressure control.ConclusionsSignificant variations exist in the prevalence of hypertension and associated CKD and its management between the major ethnic groups. Among those with CKD less than 50% were treated to a target BP of ≤ 130/80 mmHg. Rates of ACE-I/ARB prescribing for those with CKD were less than optimal, with the lowest rates (58.5%) among Black groups.

Effect of ethnicity on the prevalence, severity, and management of COPD in general practice

BACKGROUNDnChronic obstructive pulmonary disease (COPD) remains a major cause of mortality and hospital use. Little is known in the UK about the variation in COPD prevalence, severity, and management depending on ethnicity.nnnAIMnTo examine differences by ethnicity in COPD prevalence, severity, and management.nnnDESIGN & SETTINGnCross-sectional study using routinely collected computerised data from general practice in three east-London primary care trusts (Newham, Tower Hamlets, and City and Hackney) with multiethnic populations of people who are socially deprived.nnnMETHODnRoutine demographic, clinical, and hospital admission data from 140 practices were collected.nnnRESULTSnCrude COPD prevalence was 0.9%; the highest recorded rates were in the white population. Severity of COPD, measured by percentage-predicted forced expiratory volume in 1 second, did not vary by ethnicity. South Asians and black patients were less likely than white patients to have breathlessness, indicated by a Medical Research Council dyspnoea grade of ≥4 (odds ratio [OR] 0.7 [95% confidence interval (CI) = 0.6 to 0.9] and 0.6 [95% CI = 0.4 to 0.8]). Black patients were less likely than white patients to receive inhaled medications. Influenza and pneumococcal vaccine rates were highest among groups of South Asians (OR 3.0 [95% CI = 2.1 to 4.3] and 1.8 [95% CI = 1.4 to 2.3] respectively). Both minority ethnic groups had low referral rates to pulmonary rehabilitation. In Tower Hamlets, black patients were more likely to be admitted to hospital for respiratory causes.nnnCONCLUSIONnDifferences in COPD prevalence and severity by ethnicity were identified, and significant differences in drug and non-drug management and hospital admissions observed. Systematic ethnicity recording in general practice is needed to be able to explore such differences and monitor inequalities in healthcare by ethnicity.

Prescribing in general practice for people with coronary heart disease; equity by age, sex, ethnic group and deprivation.

Objective. Differences in drug prescribing for coronary heart disease have previously been identified by age, sex and ethnic group. Set in the UK, our study utilises routinely collected data from 98 general practices serving a socially diverse population in inner East London, to examine differences in prescribing rates among patients aged 35 years and over with coronary heart disease. Design. 10,933 patients aged 35 years or more, with recorded coronary heart disease, from 98 practices in two Primary Care Trusts (PCT) in East London during 2009/2010 were included for this cross-sectional study. Multivariable logistic regression was used to assess the odds of prescribing for recommended coronary heart disease drugs by age, sex, ethnicity, social deprivation, co-morbidity and recorded reasons for not prescribing. Results. Women are prescribed fewer recommended coronary heart disease drugs than men; Black African/Caribbean patients are prescribed fewer lipid modifying drugs and other cardiovascular drugs than White patients. Patients over age 84 are prescribed fewer lipid modifying drugs and beta blockers than patients aged 45–54. South Asian patients had the highest levels of prescribing and higher prevalence of coronary heart disease and diabetes co-morbidity. No difference in prescribing rates by social deprivation was found. Discussion. Overall levels of prescribing are high but small differences between sex and ethnic groups remain and prescribing may be inequitable for women, for Black/African Caribbeans and at older ages. These differences were not explained by recorded intolerance, contraindications or declining treatment.