A critical reflection on the use of improvement science approaches in public health.

OBJECTIVE: 'Improvement science' is used to describe specific quality improvement methods (including tests of change and statistical process control). The approach is spreading from clinical settings to population-wide interventions and is being extended from supporting the adoption of proven interventions to making generalisable claims about new interventions. The objective of this narrative review is to evaluate the strengths and risks of current improvement science practice, particularly in relation to how they might be used in population health. METHODS: A purposive sampling of published studies to identify how improvement science methods are being used and for what purpose. The setting was Scotland and studies that focused on health and wellbeing outcomes. RESULTS: We have identified a range of improvement science approaches which provide practitioners with accessible tools to assess small-scale changes in policy and practice. The strengths of such approaches are that they facilitate consistent implementation of interventions already known to be effective and motivate and empower staff to make local improvements. However, we also identified a number of potential risks. In particular, their use to assess the effectiveness of new interventions often seems to pay insufficient attention to random variation, measurement bias, confounding and ethical issues. CONCLUSIONS: The use of current improvement science methods to generate evidence of effectiveness for population-wide interventions is problematic and risks unjustified claims of effectiveness, inefficient resource use and harm to those not offered alternative effective interventions. Newer methodological approaches offer alternatives and should be more widely considered.

Impact of COVID-19 on care-home mortality and life expectancy in Scotland.

BACKGROUND: COVID-19 deaths are commoner among care-home residents, but the mortality burden has not been quantified. METHODS: Care-home residency was identified via a national primary care registration database linked to mortality data. Life expectancy was estimated using Makeham-Gompertz models to (i) describe yearly life expectancy from November 2015 to October 2020 (ii) compare life expectancy (during 2016-18) between care-home residents and the wider population and (iii) apply care-home life expectancy estimates to COVID-19 death counts to estimate years of life lost (YLL). RESULTS: Among care-home residents, life expectancy in 2015/16 to 2019/20 ranged from 2.7 to 2.3 years for women and 2.3 to 1.8 years for men. Age-sex-specific life expectancy in 2016-18 in care-home residents was lower than in the Scottish population (10 and 2.5 years in those aged 70 and 90, respectively). Applying care home-specific life expectancies to COVID-19 deaths yield mean YLLs for care-home residents of 2.6 and 2.2 for women and men, respectively. In total YLL care-home residents have lost 3,560 years in women and 2,046 years in men. Approximately half of deaths and a quarter of YLL attributed to COVID-19 were accounted for by the 5% of over-70s who were care-home residents. CONCLUSION: COVID-19 infection has led to the loss of substantial years of life in care-home residents aged 70 years and over in Scotland. Prioritising the 5% of older adults who are care-home residents for vaccination is justified not only in terms of total deaths, but also in terms of YLL.

Trends in incidence and case fatality of acute myocardial infarction, angina and coronary revascularisation in people with and without type 2 diabetes in Scotland between 2006 and 2015.

AIMS/HYPOTHESIS: The aim of the study was to examine trends in the incidence and case fatality of acute myocardial infarction (AMI) and in hospital admissions for angina and coronary revascularisation procedures in people with type 2 diabetes and in people without diabetes in Scotland between 2006 and 2015. METHODS: In this retrospective cohort study, AMI, angina and revascularisation event data were obtained for adults from hospital admissions and death records linked to a population-based diabetes register. Incidence by diabetes status was estimated using negative binomial models with adjustment or stratification by age, sex, deprivation and calendar year. Logistic regression was used to estimate AMI case fatality by diabetes status. RESULTS: There were 129,926 incident AMI events, 41,263 angina admissions and 69,875 coronary revascularisation procedures carried out during 34.9 million person-years of follow-up. The adjusted incidence of AMI, angina and revascularisation procedures declined by 2.0% (95% CI 1.73%, 2.26%), 9.62% (95% CI 9.22%, 10.01%) and 0.35% (95% CI -0.09%, 0.79%) per year, respectively. The rate of decline did not differ materially by diabetes status. RRs of AMI for type 2 diabetes were 1.86 (95% CI 1.74, 1.98) for men and 2.32 (95% CI 2.15, 2.51) for women. Of the 77,211 people admitted to hospital with a first AMI, 7842 (10.2%) died within 30 days of admission. Case fatality was higher in people with type 2 diabetes than in people without diabetes and declined in both groups by 7.93% (95% CI 7.03%, 8.82%) per year. CONCLUSIONS/INTERPRETATION: The incidence of AMI, angina, revascularisation and AMI case fatality has declined over time, but the increased risk associated with type 2 diabetes has remained approximately constant.

Incidence of Hospitalization for Heart Failure and Case-Fatality Among 3.25 Million People With and Without Diabetes Mellitus.

BACKGROUND: Recent clinical trials of new glucose-lowering treatments have drawn attention to the importance of hospitalization for heart failure as a complication of diabetes mellitus. However, the epidemiology is not well described, particularly for type 1 diabetes mellitus. We examined the incidence and case-fatality of heart failure hospitalizations in the entire population aged ≥30 years resident in Scotland during 2004 to 2013. METHODS: Date and type of diabetes mellitus diagnosis were linked to heart failure hospitalizations and deaths using the national Scottish registers. Incidence rates and case-fatality were estimated in regression models (quasi-Poisson and logistic regression respectively). All estimates are adjusted for age, sex, socioeconomic status, and calendar-year. RESULTS: Over the 10-year period of the study, among 3.25 million people there were 91, 429, 22 959, and 1313 incident heart failure events among those without diabetes mellitus, with type 2, and type 1 diabetes mellitus, respectively. The crude incidence rates of heart failure hospitalization were therefore 2.4, 12.4, and 5.6 per 1000 person-years for these 3 groups. Heart failure hospitalization incidence was higher in people with diabetes mellitus, regardless of type, than in people without. Relative differences were smallest for older men, in whom the difference was nonetheless large (men aged 80, rate ratio 1.78; 95% CI, 1.45-2.19). Rates declined similarly, by 0.2% per calendar-year, in people with type 2 diabetes mellitus and without diabetes mellitus. Rates fell faster, however, in those with type 1 diabetes mellitus (2.2% per calendar-year, rate ratio for type 1/calendar-year interaction 0.978; 95% CI, 0.959-0.998). Thirty-day case-fatality was similar among people with type 2 diabetes mellitus and without diabetes mellitus, but was higher in type 1 diabetes mellitus for men (odds ratio, 0.96; 95% CI, 0.95-0.96) and women (odds ratio, 0.98; 95% CI, 0.97-0.98). Case-fatality declined over time for all groups (3.3% per calendar-year, odds ratio per calendar-year 0.967; 95% CI, 0.961-0.973). CONCLUSIONS: Despite falling incidence, particularly in type 1 diabetes mellitus, heart failure remains ≈2-fold higher than in people without diabetes mellitus, with higher case-fatality in those with type 1 diabetes mellitus. These findings support the view that heart failure is an under-recognized and important complication in diabetes mellitus, particularly for type 1 disease.

Representation of people with comorbidity and multimorbidity in clinical trials of novel drug therapies: an individual-level participant data analysis.

BACKGROUND: Clinicians are less likely to prescribe guideline-recommended treatments to people with multimorbidity than to people with a single condition. Doubts as to the applicability of clinical trials of drug treatments (the gold standard for evidence-based medicine) when people have co-existing diseases (comorbidity) may underlie this apparent reluctance. Therefore, for a range of index conditions, we measured the comorbidity among participants in clinical trials of novel drug therapies and compared this to the comorbidity among patients in the community. METHODS: Data from industry-sponsored phase 3/4 multicentre trials of novel drug therapies for chronic medical conditions were identified from two repositories: Clinical Study Data Request and the Yale University Open Data Access project. We identified 116 trials (n = 122,969 participants) for 22 index conditions. Community patients were identified from a nationally representative sample of 2.3 million patients in Wales, UK. Twenty-one comorbidities were identified from medication use based on pre-specified definitions. We assessed the prevalence of each comorbidity and the total number of comorbidities (level of multimorbidity), for each trial and in community patients. RESULTS: In the trials, the commonest comorbidities in order of declining prevalence were chronic pain, cardiovascular disease, arthritis, affective disorders, acid-related disorders, asthma/COPD and diabetes. These conditions were also common in community-based patients. Mean comorbidity count for trial participants was approximately half that seen in community-based patients. Nonetheless, a substantial proportion of trial participants had a high degree of multimorbidity. For example, in asthma and psoriasis trials, 10-15% of participants had ≥ 3 conditions overall, while in osteoporosis and chronic obstructive pulmonary disease trials 40-60% of participants had ≥ 3 conditions overall. CONCLUSIONS: Comorbidity and multimorbidity are less common in trials than in community populations with the same index condition. Comorbidity and multimorbidity are, nevertheless, common in trials. This suggests that standard, industry-funded clinical trials are an underused resource for investigating treatment effects in people with comorbidity and multimorbidity.

Adverse events after first, single, mesh and non-mesh surgical procedures for stress urinary incontinence and pelvic organ prolapse in Scotland, 1997-2016: a population-based cohort study.

BACKGROUND: Concerns have been raised about the safety of surgery for stress urinary incontinence and pelvic organ prolapse using transvaginal mesh. We assessed adverse outcomes after first, single mesh procedures and comparable non-mesh procedures. METHODS: We did a cohort study of women in Scotland aged 20 years or older undergoing a first, single incontinence procedure or prolapse procedure during 1997-98 to 2015-16 identified from a national hospital admission database. Primary outcomes were immediate postoperative complications and subsequent (within 5 years) readmissions for later postoperative complications, further incontinence surgery, or further prolapse surgery. Poisson regression models were used to compare outcomes after procedures carried out with and without mesh. FINDINGS: Between April 1, 1997, and March 31, 2016, 16 660 women underwent a first, single incontinence procedure, 13 133 (79%) of which used mesh. Compared with non-mesh open surgery (colposuspension), mesh procedures had a lower risk of immediate complications (adjusted relative risk [aRR] 0·44 [95% CI 0·36-0·55]) and subsequent prolapse surgery (adjusted incidence rate ratio [aIRR] 0·30 [0·24-0·39]), and a similar risk of further incontinence surgery (0·90 [0·73-1·11]) and later complications (1·12 [0·98-1·27]); all ratios are for retropubic mesh. During the same time period, 18 986 women underwent a first, single prolapse procedure, 1279 (7%) of which used mesh. Compared with non-mesh repair, mesh repair of anterior compartment prolapse was associated with a similar risk of immediate complications (aRR 0·93 [95% CI 0·49-1·79]); an increased risk of further incontinence (aIRR 3·20 [2·06-4·96]) and prolapse surgery (1·69 [1·29-2·20]); and a substantially increased risk of later complications (3·15 [2·46-4·04]). Compared with non-mesh repair, mesh repair of posterior compartment prolapse was associated with a similarly increased risk of repeat prolapse surgery and later complications. No difference in any outcome was observed between vaginal and, separately, abdominal mesh repair of vaginal vault prolapse compared with vaginal non-mesh repair. INTERPRETATION: Our results support the use of mesh procedures for incontinence, although further research on longer term outcomes would be beneficial. Mesh procedures for anterior and posterior compartment prolapse cannot be recommended for primary prolapse repair. Both vaginal and abdominal mesh procedures for vaginal vault prolapse repair are associated with similar effectiveness and complication rates to non-mesh vaginal repair. These results therefore do not clearly favour any particular vault repair procedure. FUNDING: None.

The impact of cancer on subsequent chance of pregnancy: a population-based analysis.

STUDY QUESTION: What is the impact of cancer in females aged ≤39 years on subsequent chance of pregnancy? SUMMARY ANSWER: Cancer survivors achieved fewer pregnancies across all cancer types, and the chance of achieving a first pregnancy was also lower. WHAT IS KNOWN ALREADY: The diagnosis and treatment of cancer in young females may be associated with reduced fertility but the true pregnancy deficit in a population is unknown. STUDY DESIGN, SIZE, DURATION: We performed a retrospective cohort study relating first incident cancer diagnosed between 1981 and 2012 to subsequent pregnancy in all female patients in Scotland aged 39 years or less at cancer diagnosis (n = 23 201). Pregnancies were included up to end of 2014. Females from the exposed group not pregnant before cancer diagnosis (n = 10 271) were compared with general population controls matched for age, deprivation quintile and year of diagnosis. PARTICIPANTS/MATERIALS, SETTING, METHODS: Scottish Cancer Registry records were linked to hospital discharge records to calculate standardized incidence ratios (SIR) for pregnancy, standardized for age and year of diagnosis. Linkage to death records was also performed. We also selected women from the exposed group who had not been pregnant prior to their cancer diagnosis who were compared with a matched control group from the general population. Additional analyses were performed for breast cancer, Hodgkin lymphoma, leukaemia, cervical cancer and brain/CNS cancers. MAIN RESULTS AND THE ROLE OF CHANCE: Cancer survivors achieved fewer pregnancies: SIR 0.62 (95% CI: 0.60, 0.63). Reduced SIR was observed for all cancer types. The chance of achieving a first pregnancy was also lower, adjusted hazard ratio = 0.57 (95% CI: 0.53, 0.61) for women >5 years after diagnosis, with marked reductions in women with breast, cervical and brain/CNS tumours, and leukaemia. The effect was reduced with more recent treatment period overall and in cervical cancer, breast cancer and Hodgkin lymphoma, but was unchanged for leukaemia or brain/CNS cancers. The proportion of pregnancies that ended in termination was lower after a cancer diagnosis, and the proportion ending in live birth was higher (78.7 vs 75.6%, CI of difference: 1.1, 5.0). LIMITATIONS, REASONS FOR CAUTION: Details of treatments received were not available, so the impact of specific treatment regimens on fertility could not be assessed. Limited duration of follow-up was available for women diagnosed in the most recent time period. WIDER IMPLICATIONS OF THE FINDINGS: This analysis provides population-based quantification by cancer type of the effect of cancer and its treatment on subsequent pregnancy across the reproductive age range, and how this has changed in recent decades. The demonstration of a reduced chance of pregnancy across all cancer types and the changing impact in some but not other common cancers highlights the need for appropriate fertility counselling of all females of reproductive age at diagnosis. STUDY FUNDING/COMPETING INTEREST(S): This study was funded by NHS Lothian Cancer and Leukaemia Endowments Fund. Part of this work was undertaken in the MRC Centre for Reproductive Health which is funded by the MRC Centre grant MR/N022556/1. RAA has participated in Advisory Boards and/or received speaker's fees from Beckman Coulter, IBSA, Merck and Roche Diagnostics. He has received research support from Roche Diagnostics, Ansh labs and Ferring. The other authors have no conflicts to declare.

Trends in type 2 diabetes incidence and mortality in Scotland between 2004 and 2013.

AIMS/HYPOTHESIS: The relative contribution of increasing incidence and declining mortality to increasing prevalence of type 2 diabetes in Scotland is unclear. Trends in incidence and mortality rates are described for type 2 diabetes in Scotland between 2004 and 2013 by age, sex and socioeconomic deprivation. METHODS: Data for incident and prevalent cases of type 2 diabetes were obtained from the Scottish national diabetes register with number of deaths identified from linkage to mortality records. Population size and death data for Scotland by age, sex and socioeconomic deprivation were obtained from National Records of Scotland. Age- and sex-specific incidence and mortality rates stratified by year and deciles of socioeconomic status were calculated using Poisson models. RESULTS: There were 180,290 incident cases of type 2 diabetes in Scotland between 2004 and 2013. Overall, incidence of type 2 diabetes remained stable over time and was 4.88 (95% CI 4.84, 4.90) and 3.33 (3.28, 3.32) per 1000 in men and women, respectively. However, incidence increased among young men, remained stable in young women, and declined in older men and women. Incidence rates declined in all socioeconomic groups but increased after 2008 in the most deprived groups. Standardised mortality ratios associated with diabetes, adjusted for age and socioeconomic group, were 1.38 (1.36, 1.41) in men and 1.49 (1.45, 1.52) in women, and remained constant over time. CONCLUSIONS/INTERPRETATION: Incidence of type 2 diabetes has stabilised in recent years suggesting that increasing prevalence may be primarily attributed to declining mortality. Prevention of type 2 diabetes remains important, particularly among socioeconomically deprived populations.

Type 2 diabetes and risk of hospital admission or death for chronic liver diseases.

BACKGROUND & AIMS: The impact of type 2 diabetes (T2DM) on hospital admissions and deaths due to common chronic liver diseases (CLDs) is uncertain. Our aim was to investigate associations between T2DM and CLDs in a national retrospective cohort study and to investigate the role of sex and socio-economic status (SES). METHODS: We used International Classification of Disease codes to identify incident alcoholic liver disease (ALD), autoimmune liver disease, haemochromatosis, hepatocellular carcinoma, non-alcoholic fatty liver disease (NAFLD) and viral liver disease from linked diabetes, hospital, cancer and death records for people of 40-89years of age in Scotland 2004-2013. We used quasi Poisson regression to estimate rate ratios (RR). RESULTS: There were 6667 and 33624 first mentions of CLD in hospital, cancer and death records over ∼1.8 and 24million person-years in people with and without T2DM, respectively. The most common liver disease was ALD among people without diabetes and was NAFLD among people with T2DM. Age-adjusted RR for T2DM compared to the non-diabetic population (95% confidence intervals) varied between 1.27 (1.04-1.55) for autoimmune liver disease and 5.36 (4.41-6.51) for NAFLD. RRs were lower for men than women and for more compared to less deprived populations for both ALD and NAFLD. CONCLUSIONS: T2DM is associated with increased risk of hospital admission or death for all common CLDs and the strength of the association varies by type of CLD, sex and SES. Increasing prevalence of T2DM is likely to result in increasing burden of all CLDs.

Ethnic variations in asthma hospital admission, readmission and death: a retrospective, national cohort study of 4.62 million people in Scotland.

BACKGROUND: Our previous meta-analysis found that South Asians and Blacks in the UK were at a substantially increased risk of hospital admission from asthma. These estimates were, however, derived from pooling data from a limited number of now dated studies, confined to only three very broad ethnic groups (i.e. Whites, South Asians and Blacks) and failed to take account of possible sex-related differences in outcomes within these ethnic groups. We undertook the first study investigating ethnic variations in asthma outcomes across an entire population. METHODS: This retrospective 9-year cohort study linked Scotland's hospitalisation/death records on asthma to the 2001 census (providing ethnic group). We calculated age, country of birth and Scottish Index of Multiple Deprivation adjusted incident rate ratios (IRRs) for hospitalisation or death by sex for the period May 2001-2010. We calculated hazard ratios (HRs) for asthma readmission and subsequent asthma death. RESULTS: We were able to link data on 4.62 million people (91.8% of the Scottish population), yielding over 38 million patient-years of data, 1,845 asthma deaths, 113,795 first asthma admissions, and 107,710 readmissions (40,075 of which were for asthma). There were substantial ethnic variations in the rate of hospitalisation/death in both males and females. When compared to the reference Scottish White population, the highest age-adjusted rates were in Pakistani males (IRR = 1.59; 95% CI, 1.30-1.94) and females (IRR = 1.50; 95% CI, 1.06-2.11) and Indian males (IRR = 1.34; 95% CI, 1.16-1.54), and the lowest were seen in Chinese males (IRR = 0.62; 95% CI, 0.41-0.94) and females (IRR = 0.49; 95% CI, 0.39-0.61). CONCLUSION: There are very substantial ethnic variations in hospital admission/deaths from asthma in Scotland, with Pakistanis having the worst and Chinese having the best outcomes. Cultural factors, including self-management and health seeking behaviours, and variations in the quality of primary care provision are the most likely explanations for these differences and these now need to be formally investigated.

The epidemiology, healthcare and societal burden and costs of asthma in the UK and its member nations: analyses of standalone and linked national databases.

BACKGROUND: There are a lack of reliable data on the epidemiology and associated burden and costs of asthma. We sought to provide the first UK-wide estimates of the epidemiology, healthcare utilisation and costs of asthma. METHODS: We obtained and analysed asthma-relevant data from 27 datasets: these comprised national health surveys for 2010-11, and routine administrative, health and social care datasets for 2011-12; 2011-12 costs were estimated in pounds sterling using economic modelling. RESULTS: The prevalence of asthma depended on the definition and data source used. The UK lifetime prevalence of patient-reported symptoms suggestive of asthma was 29.5 % (95 % CI, 27.7-31.3; n = 18.5 million (m) people) and 15.6 % (14.3-16.9, n = 9.8 m) for patient-reported clinician-diagnosed asthma. The annual prevalence of patient-reported clinician-diagnosed-and-treated asthma was 9.6 % (8.9-10.3, n = 6.0 m) and of clinician-reported, diagnosed-and-treated asthma 5.7 % (5.7-5.7; n = 3.6 m). Asthma resulted in at least 6.3 m primary care consultations, 93,000 hospital in-patient episodes, 1800 intensive-care unit episodes and 36,800 disability living allowance claims. The costs of asthma were estimated at least £1.1 billion: 74 % of these costs were for provision of primary care services (60 % prescribing, 14 % consultations), 13 % for disability claims, and 12 % for hospital care. There were 1160 asthma deaths. CONCLUSIONS: Asthma is very common and is responsible for considerable morbidity, healthcare utilisation and financial costs to the UK public sector. Greater policy focus on primary care provision is needed to reduce the risk of asthma exacerbations, hospitalisations and deaths, and reduce costs.

Ethnicity and risk of cardiovascular disease (CVD): 4.8 year follow-up of patients with type 2 diabetes living in Scotland.

AIMS/HYPOTHESIS: Potential differences in cardiovascular risk by ethnicity remain uncertain. We evaluated the association of ethnicity with cardiovascular disease (CVD) incidence in a large cohort of people with type 2 diabetes living in Scotland. METHODS: Data from Scottish Care Information-Diabetes (SCI-Diabetes) were linked to Scottish Morbidity Records (SMR01) and National Records of Scotland data for mortality for dates between 2005 and 2011. Of 156,991 people with type 2 diabetes with coded ethnicity, 121,535 (77.4%) had no CVD at baseline (White: 114,461; Multiple Ethnic: 2,554; Indian: 797; Other Asian: 319; Pakistani: 2,250; Chinese: 387; African-Caribbean: 301 and Other: 466) and were followed up (mean ± SD: 4.8 ± 2.3 years) for the development of fatal and non-fatal CVD. RESULTS: During follow-up, 16,265 (13.4%) patients developed CVD (ischaemic heart or cerebrovascular diseases). At baseline, Pakistanis were younger and had developed diabetes earlier, had higher HbA1c and longer duration of diabetes, but had lower BP, BMI, creatinine, proportion of smokers and proportion on antihypertensive therapy than whites. The age and sex adjusted HRs for CVD were HR 1.31 (CI 1.17, 1.47), p < 0.001 in Pakistanis and HR 0.66 (CI 0.47, 0.92), p = 0.014 in Chinese compared with whites. Adjusting additionally for an area measure of deprivation, duration of diabetes, conventional CVD and other risk factors, the HR for Pakistanis (HR 1.45 [CI 1.14, 1.85], p = 0.002) was significantly higher, and that for Chinese (HR = 0.58 [CI 0.24, 1.40], p = 0.228) lower, compared with whites. CONCLUSIONS/INTERPRETATION: Compared with whites with type 2 diabetes, those of Pakistani ethnicity in Scotland were at increased risk of CVD, whereas Chinese were at lower risk, with these differences unexplained by known risk factors.

Understanding extreme mortality among prisoners: a national cohort study in Scotland using data linkage.

BACKGROUND: Mortality is known to be extremely high among people who have been imprisoned, but there is limited information about the factors that explain this increased risk. METHODS: Standard record linkage methods were used to link Scottish prison records and mortality data for all individuals imprisoned in Scotland for the first time between 1 January 1996 and 31 December 2007. RESULTS: Among 76 627 individuals there were 4414 deaths (3982 in men). When compared with the general population, the age-standardized mortality rate ratio for those imprisoned was 3.3 (95% CI: 3.2, 3.4) for men and 7.6 (6.9, 8.3) for women. Further adjustment for an area measure of deprivation accounted for part but not all of this excess risk [adjusted rate ratio 2.3 (2.2, 2.4) and 5.7 (5.1, 6.2) for men and women, respectively]. Relative risks were highest for drug and alcohol related causes, suicide and homicide and were markedly higher among women than men. Out of prison deaths were most frequent in the first 2 weeks after release from prison. Mortality rates were lower in those with longer total duration in prison and higher in those with multiple short episodes in prison. CONCLUSION: People who have been imprisoned in Scotland experience substantial excess mortality from a range of causes that is only partly explained by deprivation. The association of increased mortality with multiple periods in prison and the concentration of deaths in the early period after prison release both have implications for policy and practice.

Risk of respiratory hospitalization and death, readmission and subsequent mortality: scottish health and ethnicity linkage study.

BACKGROUND: Limited and dated evidence shows ethnic inequalities in health status and health care in respiratory diseases. METHODS: This retrospective, cohort study linked Scotland's hospitalization/death records on respiratory disorders to 4.65 million people in the 2001 census (providing ethnic group). For all-respiratory diseases and chronic obstructive pulmonary disease (COPD) from April 2001 to 2010 we calculated age, country of birth and Scottish Index of Multiple Deprivation (SIMD) adjusted risk ratios (RRs), by sex. We calculated hazard ratios (HRs) for death following hospitalization and for readmission. We multiplied ratios and confidence intervals (CIs) by 100, so the reference Scottish White population's RR/HR = 100. RESULTS: RRs were comparatively low for all-respiratory diseases in Other White British (84.0, 95% CI 79.6, 88.6) and Chinese (67.4, 95% CI 55.2, 82.3) men and high in Pakistani men (138.1, 95% CI 125.5, 151.9) and women (132.7, 95% CI 108.8, 161.8). For COPD, White Irish men (142.5, 95% CI 125.3, 162.1) and women (141.9, CI 124.8, 161.3) and any Mixed Background men (161, CI 127.1, 203.9) and women (215.4, CI 158.2, 293.3) had high RRs, while Indian men (54.5, CI 41.9, 70.9) and Chinese women (50.5, CI 31.4, 81.1) had low RRs. In most non-White groups, mortality following hospitalization and readmission was similar or lower than the reference. CONCLUSIONS: The pattern of ethnic variations in these respiratory disorders was complex and did not merely reflect smoking patterns. Readmission and death after hospitalization data did not signal inequity in services for ethnic minority groups.

Ethnicity and first birth: age, smoking, delivery, gestation, weight and feeding: Scottish Health and Ethnicity Linkage Study.

BACKGROUND: We linked census and health service data sets to address the shortage of information comparing maternal characteristics and pregnancy outcomes by ethnic group in Scotland. METHODS: Retrospective cohort study linking the 2001 National Census for Scotland and hospital obstetric data (2001-08), comparing maternal age, smoking status, gestational age, caesarean section rates, birthweight, preterm birth and breastfeeding rates by ethnic group. RESULTS: In all, 144 344 women were identified as having had a first birth between 1 May 2001 and 30 April 2008. White Scottish mothers were younger [mean age 27.3 years; 95% confidence interval (CI): 27.3, 27.4] than other white groups and most non-white groups. They had the highest smoking rates (25.8%; CI: 25.5, 26.0) and the lowest rates of breastfeeding at 6-8 weeks (23.4%; CI: 23.1, 23.6), with most of the other groups being around 40%. Women from non-white minority ethnic groups in Scotland tended to have babies of lower birthweight (e.g. Pakistani mean birthweight-3105 g, white Scottish-3356 g), even after adjustment for gestational age, maternal age, education, smoking and housing tenure. This effect was more noticeable for women born in the UK. White English, Irish and other white babies tended to have higher birthweights. There was little variation between groups in caesarean section rates. CONCLUSIONS: Pregnant women from ethnic minority populations in Scotland have more favourable health behaviour than the white Scottish, although the non-white groups tend to have lower birthweight. Further exploration of the reasons for these differences has potential to benefit women from the majority population.

Smoke-free legislation and hospitalizations for childhood asthma.

BACKGROUND: Previous studies have shown that after the adoption of comprehensive smoke-free legislation, there is a reduction in respiratory symptoms among workers in bars. However, it is not known whether respiratory disease is also reduced among people who do not have occupational exposure to environmental tobacco smoke. The aim of our study was to determine whether the ban on smoking in public places in Scotland, which was initiated in March 2006, influenced the rate of hospital admissions for childhood asthma. METHODS: Routine hospital administrative data were used to identify all hospital admissions for asthma in Scotland from January 2000 through October 2009 among children younger than 15 years of age. A negative binomial regression model was fitted, with adjustment for age group, sex, quintile of socioeconomic status, urban or rural residence, month, and year. Tests for interactions were also performed. RESULTS: Before the legislation was implemented, admissions for asthma were increasing at a mean rate of 5.2% per year (95% confidence interval [CI], 3.9 to 6.6). After implementation of the legislation, there was a mean reduction in the rate of admissions of 18.2% per year relative to the rate on March 26, 2006 (95% CI, 14.7 to 21.8; P<0.001). The reduction was apparent among both preschool and school-age children. There were no significant interactions between hospital admissions for asthma and age group, sex, urban or rural residence, region, or quintile of socioeconomic status. CONCLUSIONS: In Scotland, passage of smoke-free legislation in 2006 was associated with a subsequent reduction in the rate of respiratory disease in populations other than those with occupational exposure to environmental tobacco smoke. (Funded by NHS Health Scotland.)

Socioeconomic deprivation increases the effect of winter on admissions to hospital with COPD: retrospective analysis of 10 years of national hospitalisation data.

BACKGROUND: Admission to hospital with chronic obstructive pulmonary disease (COPD) is associated with deprivation and season. However, it is not known whether deprivation and seasonality act synergistically to influence the risk of hospital admission with COPD. AIMS: To investigate whether the relationship between season/temperature and admission to hospital with COPD differs with deprivation. METHODS: All COPD admissions (ICD10 codes J40-J44 and J47) were obtained for the decade 2001-2010 for all Scottish residents by month of admission and 2009 Scottish Index of Multiple Deprivation (SIMD) quintile. Confidence intervals for rates and absolute differences in rates were calculated and the proportion of risk during winter attributable to main effects and interactions were estimated. Monthly rates of admission by average daily minimum temperatures were plotted for each quintile of SIMD. RESULTS: Absolute differences in admission rates between winter and summer increased with greater deprivation. In the most deprived quintile, in winter 19.4% (95% CI 17.3% to 21.4%) of admissions were attributable to season/deprivation interaction, 61.2% (95% CI 59.5% to 63.0%) to deprivation alone, and 5.2% (95% CI 4.3% to 6.0%) to winter alone. Lower average daily minimum temperatures over a month were associated with higher admission rates, with stronger associations evident in the more deprived quintiles. CONCLUSIONS: Winter and socioeconomic deprivation-related factors appear to act synergistically, increasing the rate of COPD admissions to hospital more among deprived people than among affluent people in winter than in the summer months. Similar associations were observed for admission rates and temperatures. Interventions effective at reducing winter admissions for COPD may have potential for greater benefit if delivered to more deprived groups.

Cardiovascular disease and air pollution in Scotland: no association or insufficient data and study design?

BACKGROUND: Coronary heart disease and stroke are leading causes of mortality and ill health in Scotland, and clear associations have been found in previous studies between air pollution and cardiovascular disease. This study aimed to use routinely available data to examine whether there is any evidence of an association between short-term exposure to particulate matter (measured as PM10, particles less than 10 micrograms per cubic metre) and hospital admissions due to cardiovascular disease, in the two largest cities in Scotland during the years 2000 to 2006. METHODS: The study utilised an ecological time series design, and the analysis was based on overdispersed Poisson log-linear models. RESULTS: No consistent associations were found between PM10 concentrations and cardiovascular hospital admissions in either of the cities studied, as all of the estimated relative risks were close to one, and all but one of the associated 95% confidence intervals contained the null risk of one. CONCLUSIONS: This study suggests that in small cities, where air quality is relatively good, then either PM10 concentrations have no effect on cardiovascular ill health, or that the routinely available data and the corresponding study design are not sufficient to detect an association.

Measuring disability-adjusted life years (DALYs) due to COVID-19 in Scotland, 2020.

BACKGROUND: Disability-adjusted life years (DALYs) combine the impact of morbidity and mortality and can enable comprehensive, and comparable, assessments of direct and indirect health harms due to COVID-19. Our aim was to estimate DALYs directly due to COVID-19 in Scotland, during 2020; and contextualise its population impact relative to other causes of disease and injury. METHODS: National deaths and daily case data were used. Deaths were based on underlying and contributory causes recorded on death certificates. We calculated DALYs based on the COVID-19 consensus model and methods outlined by the European Burden of Disease Network. DALYs were presented as a range, using a sensitivity analysis based on Years of Life Lost estimates using: cause-specific; and COVID-19 related deaths. All COVID-19 estimates were for 2020. RESULTS: In 2020, estimates of COVID-19 DALYs in Scotland ranged from 96,500 to 108,200. Direct COVID-19 DALYs were substantial enough to be framed as the second leading cause of disease and injury, with only ischaemic heart disease having a larger impact on population health. Mortality contributed 98% of total DALYs. CONCLUSIONS: The direct population health impact of COVID-19 has been very substantial. Despite unprecedented mitigation efforts, COVID-19 developed from a single identified case in early 2020 to a condition with an impact in Scotland second only to ischaemic heart disease. Periodic estimation of DALYs during 2021, and beyond, will provide indications of the impact of DALYs averted due to the national rollout of the vaccination programme and other continued mitigation efforts, although new variants may pose significant challenges.