Serum Leptin Concentration, Body Mass Index and Incident Heart Failure: The Health, Aging, and Body Composition Study

Background: Leptin is produced primarily by adipocytes. Although originally associated with the central regulation of satiety and energy metabolism, increasing evidence indicates that leptin may be an important factor for congestive heart faire (CHF). In the study, we aimed to test the hypothesis that leptin may influence CHF pathophysiology via a pathway of increasing body mass index (BMI). Methods: We studied 2,389 elderly participants aged 70 and older (M; 1161, F: 1228) without CHF and with serum leptin measures at the Health Aging, and Body Composition study. We analyzed the association between serum leptin level and risk of incident CHF using Cox hazard proportional regression models. Elevated leptin level was defined as more than the highest quartile (Q4) of leptin distribution in the total sample for each gender. Adjusted-covariates included demographic, behavior, lipid and inflammation variables (partially-adjusted models), and further included BMI (fully-adjusted models). Results: In a mean 9-year follow-up, 316 participants (13.2%) developed CHF. The partially-adjusted models indicated that men and women with elevated serum leptin levels (>=9.89 ng/ml in men and >=25 ng/ml in women) had significantly higher risks of developing CHF than those with leptin level of less than Q4. The adjusted hazard ratios (95%CI) for incident CHF was 1.49 (1.04 -2.13) in men and 1.71 (1.12 -2.58) in women. However, these associations became non-significant after adjustment for including BMI for each gender. The fully-adjusted hazard ratios (95%CI) were 1.43 (0.94 -2.18) in men and 1.24 (0.77-1.99) in women. Conclusion: Subjects with elevated leptin levels have a higher risk of CHF. The study supports the hypothesis that the influence of leptin level on risk of CHF may be through a pathway related to increasing BMI.

Effort, reward and self-reported mental health: a simulation study on negative affectivity bias.

Background : In the present article, we propose an alternative method for dealing with negative affectivity (NA) biases in research, while investigating the association between a deleterious psychosocial environment at work and poor mental health. First, we investigated how strong NA must be to cause an observed correlation between the independent and dependent variables. Second, we subjectively assessed whether NA can have a large enough impact on a large enough number of subjects to invalidate the observed correlations between dependent and independent variables.Methods : We simulated 10,000 populations of 300 subjects each, using the marginal distribution of workers in an actual population that had answered the Siegrist's questionnaire on effort and reward imbalance (ERI) and the General Health Questionnaire (GHQ).Results : The results of the present study suggested that simulated NA has a minimal effect on the mean scores for effort and reward. However, the correlations between the effort and reward imbalance (ERI) ratio and the GHQ score might be important, even in simulated populations with a limited NA.Conclusions : When investigating the relationship between the ERI ratio and the GHQ score, we suggest the following rules for the interpretation of the results: correlations with an explained variance of 5% and below should be considered with caution; correlations with an explained variance between 5% and 10% may result from NA, although this effect does not seem likely; and correlations with an explained variance of 10% and above are not likely to be the result of NA biases. [Authors]

Structure du temps de travail des infirmières de santé publique: effets de l'âge des patients, de la nature des prestations fournies et du lieu du contact. [Structure of work times of public health nurses: effect of the age of patients, nature of care given and location of contact].

In the framework of health services research sponsored by the Swiss National Science Foundation, a research was undertaken of the activity of the large majority of the public health nurses working in the Swiss cantons of Vaud and Fribourg (total population 700,000). During one week, 130 nurses gathered, with a specially devised instrument, data on 4165 patient visits. Studying the duration of the contacts, one has distinguished contact duration per se (DC), duration of the travel time preceding the contact (DD), and total duration in relation with the contact (DTC-addition of the first two). It was noted that the three durations increased significantly with patient age (as regard travel time, this is explained by the higher proportion of home visits in higher age groups, as compared with visits at a health center). Examined according to location of the visit, contact duration per se (without travel) is higher for visits at home and in nursing homes than for those taking place at a health center. Looked at in respect to the care given (technical care, or basic nursing care, or both simultaneously), our data show that the provision of basic nursing care (alone or with technical care) doubles contact duration (from 20 to 42-45'). The analyses according to patient age shows that, at an advanced age (beyond 80 years particularly), there is an important increase of the visits where both types of care are given. However, contact duration per se shows a significant raise with age only for the group "technical care only"; it can be demonstrated that this is due to the fact that older patients require more complex technical acts (e.g., bladder care, as compared with simpler acts such as injection). A model of the relationships between patient age and contact duration is proposed: it is because of the increase in the proportions of home visits, of visits including basic nursing care, and of more complex technical acts that older persons require more of the working time of public health nurses.

Adolescent Drug Abuse Diagnosis (ADAD) vs. Health of Nation Outcome Scale for Children and Adolescents (HoNOSCA) in clinical outcome measurement.

BACKGROUND: The Adolescent Drug Abuse Diagnosis (ADAD) and Health of Nation Outcome Scales for Children and Adolescents (HoNOSCA) are both measures of outcome for adolescent mental health services. AIMS: To compare the ADAD with HoNOSCA; to examine their clinical usefulness. METHODS: Comparison of the ADAD and HoNOSCA outcome measures of 20 adolescents attending a psychiatric day care unit. RESULTS: ADAD change was positively correlated with HoNOSCA change. HoNOSCA assesses the clinic's day-care programme more positively than the ADAD. The ADAD detects a group for which the mean score remains unchanged whereas HoNOSCA does not. CONCLUSIONS: A good convergent validity emerges between the two assessment tools. The ADAD allows an evidence-based assessment and generally enables a better subject discrimination than HoNOSCA. HoNOSCA gives a less refined evaluation but is more economic in time and possibly more sensitive to change. Both assessment tools give useful information and enabled the Day-care Unit for Adolescents to rethink the process of care and of outcome, which benefited both the institution and the patients.

Public Governance, Health and Foreign Direct Investment in Sub-Saharan Africa

In this paper we diverge from the existing empirical literature on FDI determinants in two ways. First, we decompose the sources of the foreign direct investment (FDI) gap between Sub-Saharan Africa (SSA) and other developing regions. Once market size has been accounted for, we nd that SSA's FDI de cit is mostly explained by insufficient provision of public goods: low human capital accumulation, especially health, in SSA explains 100-140% of the inter-regional FDI gaps. Second, we estimate the indirect effect of infectious diseases on FDI through their direct impact on health. We find that a 1% point rise in HIV prevalence in the adult population is associated with a decrease in net FDI inflows of 3.5%, while a country in which 100% of the population is at risk of contracting deadly malaria receives about 16% less FDI than a similar country located in a malaria-free region.

Longitudinal analysis of income-related health inequality

This paper considers the characterisation and measurement of income-related health inequality using longitudinal data. The paper elucidates the nature of the Jones and Lopez Nicholas (2004) index of “health-related income mobility” and explains the negative values of the index that have been reported in all the empirical applications to date. The paper further questions the value of their index to health policymakers and proposes an alternative index of “income-related health mobility” that measures whether the pattern of health changes is biased in favour of those with initially high or low incomes. We illustrate our work by investigating mobility in the General Health Questionnaire measure of psychological well-being over the first nine waves of the British Household Panel Survey from 1991 to 1999.

Choice of Contracts in the British National Health Service: An Empirical Study

Following major reforms of the British National Health Service (NHS) in 1990, the roles of purchasing and providing health services were separated, with the relationship between purchasers and providers governed by contracts. Using a mixed multinomial logit analysis, we show how this policy shift led to a selection of contracts that is consistent with the predictions of a simple model, based on contract theory, in which the characteristics of the health services being purchased and of the contracting parties influence the choice of contract form. The paper thus provides evidence in support of the practical relevance of theory in understanding health care market reform.

The Effect of Activity-Based Payment on Dentists’ Activity: Evidence from a Natural Experiment in the UK National Health Service

The extent to which remuneration systems affect the behaviour of health care professionals is of considerable importance in the administration of publicly funded heath care systems. Using data across two jurisdictions in the United Kingdom, in only one of which remuneration was changed, we compare the extent of measured dental activity at the dentist level in order to ascertain the impact of moving to activity-based remuneration. We find that there are large and statistically significant increases in activity as dentists moved to the activity-based system and that a dentist’s previous form of contract is an important determinant of the magnitude of the effect. We also explore the extent to which dentists’ professional attitudes can explain differences in their activity and find that some aspects of self-reported attitudes are associated with observable differences in activity.

Recruitment and retention incentives in health labour markets: an analysis of participation in NHS Scotland following Dental Vocational

This paper uses a unique individual level administrative data set to analyse the participation of health professionals in the NHS after training. The data set contains information on over 1,000 dentists who received Dental Vocational Training in Scotland between 1995 and 2006. Using a dynamic nonlinear panel data model, we estimate the determinants of post-training participation. We nd there is signi cant persistence in these data and are able to show that the persistence arises from state dependence and individual heterogeneity. This finding has implications for the structure of policies designed to increase participation rates. We apply this empirical framework to assess the accuracy of predictions for workforce forecasting, and to provide a preliminary estimate of the impact of one of the recruitment and retention policies available to dentists in Scotland.

Paper 2: EUROCAT public health indicators for congenital anomalies in Europe.

OBJECTIVE: The purpose of this article is to present the specific public health indicators recently developed by EUROCAT that aim to summarize important aspects of the public health impact of congenital anomalies in a few quantitative measures. METHODS: The six indicators are: (1) congenital anomaly perinatal mortality, (2) congenital anomaly prenatal diagnosis prevalence, (3) congenital anomaly termination of pregnancy, (4) Down syndrome livebirth prevalence, (5) congenital anomaly pediatric surgery, and (6) neural tube defects (NTD) total prevalence. Data presented for this report pertained to all cases (livebirths, fetal deaths, or stillbirths after 20 weeks of gestation and terminations of pregnancy for fetal anomaly [TOPFA]) of congenital anomaly from 27 full member registries of EUROCAT that could provide data for at least 3 years during the period 2004 to 2008. Prevalence of anomalies, prenatal diagnosis, TOPFA, pediatric surgery, and perinatal mortality were calculated per 1000 births. RESULTS: The overall perinatal mortality was approximately 1.0 per 1000 births for EUROCAT registries with almost half due to fetal and the other half due to first week deaths. There were wide variations in perinatal mortality across the registries with the highest rates observed in Dublin and Malta, registries in countries where TOPFA are illegal, and in Ukraine. The overall perinatal mortality across EUROCAT registries slightly decreased between 2004 and 2008 due to a decrease in first week deaths. The prevalence of TOPFA was fairly stable at about 4 per 1000 births. There were variations in livebirth prevalence of cases typically requiring surgery across the registries; however, for most registries this prevalence was between 3 and 5 per 1000 births. Prevalence of NTD decreased by about 10% from 1.05 in 2004 to 0.94 per 1000 in 2008. CONCLUSION: It is hoped that by publishing the data on EUROCAT indicators, the public health importance of congenital anomalies can be clearly summarized to policy makers, the need for accurate data from registries emphasized, the need for primary prevention and treatment services highlighted, and the impact of current services measured.

Measuring Avoidable Health Inequality with Realization of Conditional Potential Life Years (RCPLY)

In a series of papers (Tang, Chin and Rao, 2008; and Tang, Petrie and Rao 2006 & 2007), we have tried to improve on a mortality-based health status indicator, namely age-at-death (AAD), and its associated health inequality indicators that measure the distribution of AAD. The main contribution of these papers is to propose a frontier method to separate avoidable and unavoidable mortality risks. This has facilitated the development of a new indicator of health status, namely the Realization of Potential Life Years (RePLY). The RePLY measure is based on the concept of a “frontier country” that, by construction, has the lowest mortality risks for each age-sex group amongst all countries. The mortality rates of the frontier country are used as a proxy for the unavoidable mortality rates, and the residual between the observed mortality rates and the unavoidable mortality rates are considered as avoidable morality rates. In this approach, however, countries at different levels of development are benchmarked against the same frontier country without considering their heterogeneity. The main objective of the current paper is to control for national resources in estimating (conditional) unavoidable and avoidable mortality risks for individual countries. This allows us to construct a new indicator of health status – Realization of Conditional Potential Life Years (RCPLY). The paper presents empirical results from a dataset of life tables for 167 countries from the year 2000, compiled and updated by the World Health Organization. Measures of national average health status and health inequality based on RePLY and RCPLY are presented and compared.

What Belongs Where? Variable Selection for Zero-Inflated Count Models with an Application to the Demand for Health Care

This paper develops stochastic search variable selection (SSVS) for zero-inflated count models which are commonly used in health economics. This allows for either model averaging or model selection in situations with many potential regressors. The proposed techniques are applied to a data set from Germany considering the demand for health care. A package for the free statistical software environment R is provided.