Janet Bouttell

Recent cohort effects in suicide in Scotland: a legacy of the 1980s?

Background Mortality rates are higher in Scotland relative to England and Wales, even after accounting for deprivation. This ‘excess’ mortality is partly due to higher mortality from alcohol-related and drug-related deaths, violence and suicide (particularly in young adults). This study investigated whether cohort effects from exposure to neoliberal politics from the 1980s might explain the recent trends in suicide in Scotland. Methods We analysed suicide deaths data from 1974 to 2013 by sex and deprivation using shaded contour plots and intrinsic estimator regression modelling to identify and quantify relative age, period and cohort effects. Results Suicide was most common in young adults (aged around 25–40 years) living in deprived areas, with a younger peak in men. The peak age for suicide fell around 1990, especially for men for whom it dropped quickly from around 50 to 30 years. There was evidence of an increased risk of suicide for the cohort born between 1960 and 1980, especially among men living in the most deprived areas (of around 30%). The cohort at highest risk occurred earlier in the most deprived areas, 1965–1969 compared with 1970–1974. Conclusions The risk of suicide increased in Scotland for those born between 1960 and 1980, especially for men living in the most deprived areas, which resulted in a rise in age-standardised rates for suicide among young adults during the 1990s. This is consistent with the hypothesis that exposure to neoliberal politics created a delayed negative health impact.

Explaining trends in alcohol-related harms in Scotland, 1991–2011 (I): the role of incomes, effects of socio-economic and political adversity and demographic change

OBJECTIVE This paper tests the extent to which differing trends in income, demographic change and the consequences of an earlier period of social, economic and political change might explain differences in the magnitude and trends in alcohol-related mortality between 1991 and 2011 in Scotland compared to England & Wales (E&W). STUDY DESIGN Comparative time trend analyses and arithmetic modelling. METHODS Three approaches were utilised to compare Scotland with E&W: 1. We modelled the impact of changes in income on alcohol-related deaths between 1991-2001 and 2001-2011 by applying plausible assumptions of the effect size through an arithmetic model. 2. We used contour plots, graphical exploration of age-period-cohort interactions and calculation of Intrinsic Estimator coefficients to investigate the effect of earlier exposure to social, economic and political adversity on alcohol-related mortality. 3. We recalculated the trends in alcohol-related deaths using the white population only to make a crude approximation of the maximal impact of changes in ethnic diversity. RESULTS Real incomes increased during the 1990s but declined from around 2004 in the poorest 30% of the population of Great Britain. The decline in incomes for the poorest decile, the proportion of the population in the most deprived decile, and the inequality in alcohol-related deaths, were all greater in Scotland than in E&W. The model predicted less of the observed rise in Scotland (18% of the rise in men and 29% of the rise in women) than that in E&W (where 60% and 68% of the rise in men and women respectively was explained). One-third of the decline observed in alcohol-related mortality in Scottish men between 2001 and 2011 was predicted by the model, and the model was broadly consistent with the observed trends in E&W and amongst women in Scotland. An age-period interaction in alcohol-related mortality was evident for men and women during the 1990s and 2000s who were aged 40-70 years and who experienced rapidly increasing alcohol-related mortality rates. Ethnicity is unlikely to be important in explaining the trends or differences between Scotland and E&W. CONCLUSIONS The decline in alcohol-related mortality in Scotland since the early 2000s and the differing trend to E&W were partly described by a model predicting the impact of declining incomes. Lagged effects from historical social, economic and political change remain plausible from the available data.

Evaluating the impact of a national naloxone programme on ambulance attendance at overdose incidents: a controlled time series analysis

Abstract Background and Aims It has been suggested that distributing naloxone to people who inject drugs (PWID) will lead to fewer attendances by emergency medical services at opioid‐related overdose incidents if peer administration of naloxone was perceived to have resuscitated the overdose victim successfully. This study evaluated the impact of a national naloxone programme (NNP) on ambulance attendance at opioid‐related overdose incidents throughout Scotland. Specifically, we aimed to answer the following research questions: is there evidence of an association between ambulance call‐outs to opioid‐related overdose incidents and the cumulative number of ‘take‐home naloxone’ (THN) kits in issue; and is there evidence of an association between ambulance call‐outs to opioid‐related overdose incidents in early adopter (pilot) or later adopting (non‐pilot) regions and the cumulative number of THN kits issued in those areas? Design Controlled time–series analysis. Setting Scotland, UK, 2008–15. Participants Pre‐NNP implementation period for the evaluation was defined as 1 April 2008 to 31 March 2011 and the post‐implementation period as 1 April 2011 to 31 March 2015. In total, 3721 ambulance attendances at opioid‐related overdose were recorded for the pre‐NNP implementation period across 158 weeks (mean 23.6 attendances per week) and 5258 attendances across 212 weeks in the post‐implementation period (mean 24.8 attendances per week). Intervention Scotlands NNP; formally implemented on 1 April 2011. Measurements Primary outcome measure was weekly incidence (counts) of call‐outs to opioid‐related overdoses at national and regional Health Board level. Data were acquired from the Scottish Ambulance Service (SAS). Models were adjusted for opioid replacement therapy using data acquired from the Information Services Division on monthly sums of all dispensed methadone and buprenorphine in the study period. Models were adjusted further for a control group: weekly incidence (counts) of call‐outs to heroin‐related overdose in the London Borough area acquired from the London Ambulance Service. Findings There was no significant association between SAS call‐outs to opioid‐related overdose incidents and THN kits in issue for Scotland as a whole (coefficient 0.009, 95% confidence intervals = −0.01, 0.03, P = 0.39). In addition, the magnitude of association between THN kits and SAS call‐outs did not differ significantly between pilot and non‐pilot regions (interaction test, P = 0.62). Conclusions The supply of take‐home naloxone kits through a National Naloxone Programme in Scotland was not associated clearly with a decrease in ambulance attendance at opioid‐related overdose incidents in the 4‐year period after it was implemented in April 2011.

Explaining trends in alcohol-related harms in Scotland 1991–2011 (II): policy, social norms, the alcohol market, clinical changes and a synthesis

OBJECTIVE To provide a basis for evaluating post-2007 alcohol policy in Scotland, this paper tests the extent to which pre-2007 policy, the alcohol market, culture or clinical changes might explain differences in the magnitude and trends in alcohol-related mortality outcomes in Scotland compared to England & Wales (E&W). STUDY DESIGN Rapid literature reviews, descriptive analysis of routine data and narrative synthesis. METHODS We assessed the impact of pre-2007 Scottish policy and policy in the comparison areas in relation to the literature on effective alcohol policy. Rapid literature reviews were conducted to assess cultural changes and the potential role of substitution effects between alcohol and illicit drugs. The availability of alcohol was assessed by examining the trends in the number of alcohol outlets over time. The impact of clinical changes was assessed in consultation with key informants. The impact of all the identified factors were then summarised and synthesised narratively. RESULTS The companion paper showed that part of the rise and fall in alcohol-related mortality in Scotland, and part of the differing trend to E&W, were predicted by a model linking income trends and alcohol-related mortality. Lagged effects from historical deindustrialisation and socio-economic changes exposures also remain plausible from the available data. This paper shows that policy differences or changes prior to 2007 are unlikely to have been important in explaining the trends. There is some evidence that aspects of alcohol culture in Scotland may be different (more concentrated and home drinking) but it seems unlikely that this has been an important driver of the trends or the differences with E&W other than through interaction with changing incomes and lagged socio-economic effects. Substitution effects with illicit drugs and clinical changes are unlikely to have substantially changed alcohol-related harms: however, the increase in alcohol availability across the UK is likely to partly explain the rise in alcohol-related mortality during the 1990s. CONCLUSIONS Future policy should ensure that alcohol affordability and availability, as well as socio-economic inequality, are reduced, in order to maintain downward trends in alcohol-related mortality in Scotland.

The SCottish Alcoholic Liver disease Evaluation: A Population-Level Matched Cohort Study of Hospital-Based Costs, 1991-2011.

Studies assessing the costs of alcoholic liver disease are lacking. We aimed to calculate the costs of hospitalisations before and after diagnosis compared to population controls matched by age, sex and socio-economic deprivation. We aimed to use population level data to identify a cohort of individuals hospitalised for the first time with alcoholic liver disease in Scotland between 1991 and 2011.Incident cases were classified by disease severity, sex, age group, socio-economic deprivation and year of index admission. 5 matched controls for every incident case were identified from the Scottish population level primary care database. Hospital costs were calculated for both cases and controls using length of stay from morbidity records and hospital-specific daily rates by specialty. Remaining lifetime costs were estimated using parametric survival models and predicted annual costs. 35,208 incident alcoholic liver disease hospitalisations were identified. Mean annual hospital costs for cases were 2.3 times that of controls pre diagnosis (£804 higher) and 10.2 times (£12,774 higher) post diagnosis. Mean incident admission cost was £6,663. Remaining lifetime cost for a male, 50–59 years old, living in the most deprived area diagnosed with acoholic liver disease was estimated to be £65,999 higher than the matched controls (£12,474 for 7.43 years remaining life compared to £1,224 for 21.8 years). In Scotland, alcoholic liver disease diagnosis is associated with significant increases in admissions to hospital both before and after diagnosis. Our results provide robust population level estimates of costs of alcoholic liver disease for the purposes of health-care delivery, planning and future cost-effectiveness analyses.

Synthetic control methodology as a tool for evaluating population-level health interventions

Background Many public health interventions cannot be evaluated using randomised controlled trials so they rely on the assessment of observational data. Techniques for evaluating public health interventions using observational data include interrupted time series analysis, panel data regression-based approaches, regression discontinuity and instrumental variable approaches. The inclusion of a counterfactual improves causal inference for approaches based on time series analysis, but the selection of a suitable counterfactual or control area can be problematic. The synthetic control method builds a counterfactual using a weighted combination of potential control units. Methods We explain the synthetic control method, summarise its use in health research to date, set out its advantages, assumptions and limitations and describe its implementation through a case study of life expectancy following German reunification. Results Advantages of the synthetic control method are that it offers an approach suitable when there is a small number of treated units and control units and it does not rely on parallel preimplementation trends like difference in difference methods. The credibility of the result relies on achieving a good preimplementation fit for the outcome of interest between treated unit and synthetic control. If a good preimplementation fit is established over an extended period of time, a discrepancy in the outcome variable following the intervention can be interpreted as an intervention effect. It is critical that the synthetic control is built from a pool of potential controls that are similar to the treated unit. There is currently no consensus on what constitutes a ‘good fit’ or how to judge similarity. Traditional statistical inference is not appropriate with this approach, although alternatives are available. From our review, we noted that the synthetic control method has been underused in public health. Conclusions Synthetic control methods are a valuable addition to the range of approaches for evaluating public health interventions when randomisation is impractical. They deserve to be more widely applied, ideally in combination with other methods so that the dependence of findings on particular assumptions can be assessed.

The short‐term impact of the alcohol act on alcohol‐related deaths and hospital admissions in Scotland: a natural experiment

Abstract Background and aim The introduction of the Alcohol Act in Scotland on 1 October 2011, which included a ban on multi‐buy promotions, was probably associated with a fall in off‐trade alcohol sales in the year after its implementation. The aim of this study was to test if the same legislation was associated with reduced levels of alcohol‐related deaths and hospital admissions in the 3‐year period after its introduction. Design A natural experiment design using time–series data to assess the impact of the Alcohol Act legislation in Scotland. Comparisons were made with unexposed populations in the rest of Great Britain. Setting Scotland with comparable data obtained for geographical control groups in other parts of Great Britain. Participants For alcohol‐related deaths, a total of 17 732 in Scotland and 88 001 in England and Wales throughout 169 4‐week periods between January 2001 and December 2013 and for alcohol‐related hospital admissions, a total of 121 314 in Scotland and 696 892 in England throughout 182 4‐week periods between January 2001 and December 2014. Measurements Deaths and hospital admissions in Scotland and control groups that were wholly attributable to alcohol for consecutive 4‐week periods between January 2001 and December 2014. Data were obtained by age, sex and area‐based socio‐economic position. Findings There was no evidence to suggest that the Alcohol Act was associated with changes in the overall rate of alcohol‐related deaths [incidence rate ratio (IRR) = 0.99, 95% confidence interval (CI) = 0.91–1.07)] or hospital admissions (IRR = 0.98, 95% CI = 0.95–1.02) in Scotland. In control group analyses, the pseudo intervention variable was not associated with a change in alcohol‐related death rates in England/Wales (IRR = 0.99, 95% CI = 0.95–1.02), but was associated with an increase in alcohol‐related hospital admission rates in England (IRR = 1.05, 95% CI = 1.03–1.07). In combined models, the interaction analysis did not provide support for a ‘net effect’ of the legislation on alcohol‐related deaths in Scotland compared with England/Wales (IRR 0.99, 95% CI = 0.95–1.04), but suggested a net reduction in hospital admissions for Scotland compared with England (IRR = 0.93, 95% CI = 0.87–0.98). Conclusion The implementation of the Alcohol Act in Scotland has not been associated clearly with a reduction in alcohol‐related deaths or hospital admissions in the 3‐year period after it was implemented in October 2011.

Investigation of age, period, and cohort effects to understand Scotland's excess mortality: use of Lexis diagrams and intrinsic estimator regression modelling

Abstract Background Mortality rates are higher in Scotland than in England and Wales, even after accounting for deprivation. This excess mortality is partly due to higher mortality from suicide, alcohol-related deaths, and drug-related deaths. We investigated whether age, period, or cohort effects from exposure to adversity from the 1980s might explain the recent trends in these outcomes in Scotland. Methods Data on registered alcohol-related deaths (36 635) and suicide (31 061) for 1974–2013, and drug-related deaths (15 427) for 1979–2013 were obtained from the National Records of Scotland. To identify and quantify relative age–period–cohort effects, data were analysed by sex and deprivation using line plots, shaded contour plots (Lexis diagrams commonly used in demography but limited in epidemiology and health sciences), and intrinsic estimator regression modelling. Findings Cohort effects were identified for people born between 1960 and 1980 for both drug-related deaths and suicide. The 1960–80 birth cohort had roughly a 30% higher risk of suicide than other generations, and the increase in risk of drug-related deaths was at least twice as high. Both cohort effects were largely driven by male sex and people living in the most deprived areas, but the birth cohort most affected by suicide occurred slightly earlier than for drug-related deaths. The timing of the cohort at highest risk also differed by deprivation for both suicide and drug-related deaths, being earlier for men in the most deprived group. By contrast, an age–period effect for working-age adults, particularly in the most deprived areas, helped explain the trends in alcohol-related deaths; the risk of these deaths increased at least two times from 1990 to the mid-2000s. Interpretation The results for drug-related deaths and suicide are consistent with the hypothesis that exposure to the changing socioeconomic and political contexts of the 1980s created a delayed negative health impact because the populations most affected were the same as those subsequently with higher risks of mortality. Limitations include definition of death outcomes, changes to coding, the use of year of registration, difficulties in disentangling age–period–cohort effects, and only having a partial view of each birth cohort. The use of several methods in triangulation added strength to the findings. Funding None.