Scottish Keep Well health check programme: an interrupted time series analysis

Interrupted time series analysis on first cardiovascular disease hospitalization for adherence to lipid-lowering therapy

PURPOSE

We analysed lipid-lowering medication adherence before and after the first hospitalization for cardiovascular disease (CVD) to explore the influence hospitalization has on patient medication adherence.

METHODS

We extracted a sub-cohort for analysis from 313,207 patients who had primary CVD risk assessment. Adherence was assessed as proportion of days covered (PDC) ≥ 80% based on community dispensing records. Adherence in the 4 quarters (360 days) before the first CVD hospitalization and 8 quarters (720 days) after hospital discharge was assessed for each individual in the sub-cohort. An interrupted time series design using generalized estimating equations was applied to compare the differences of population-level medication adherence rates before and after the first CVD hospitalization.

RESULTS

Overall, a significant improvement in medication adherence rate from before to after the hospitalization was observed (odds ratio (OR) 2.49 [1.74-3.57]) among the 946 patients included in the analysis. Patients having diabetes history had a higher OR of adherence before the hospitalization than patients without diabetes (1.50 [1.03-2.22]) but no significant difference after the hospitalization (OR 1.13 [0.89-1.43]). Before the first hospitalization, we observed that quarterly medication adherence rate was steady at around 55% (OR 0.97 [0.93-1.01), whereas the trend in adherence over the post-hospitalization period decreased significantly per quarter (OR 0.97 [0.94-0.99]).

CONCLUSIONS

Patients were more likely to adhere to lipid-lowering therapy after experiencing a first CVD hospitalization. The change in medication adherence rate is consistent with patients having heightened perception of disease severity following the hospitalization.

Effectiveness of the Mobile Emergency Medical Services (SAMU): use of interrupted time series

OBJECTIVE

To evaluate the performance of the Mobile Emergency Medical Services (SAMU) in the ABC Region, using myocardial infarction as tracer condition.

METHODS

The analysis of interrupted time series was the approach chosen to test immediate and gradual effects of the intervention on the study population. The research comprised adjusted monthly time series of the hospital mortality rate by myocardial infarction in the period between 2000 and 2011. Data were extracted from the Mortality Information System (SIM), using segmented regression analysis to evaluate the level and trend of the intervention before and after its implementation. To strengthen the internal validity of the study, a control region was included.

RESULTS

The analysis of interrupted time series showed a reduction of 0.04 deaths per 100,000 inhabitants in the mortality rate compared to the underlying trend since the implementation of the Emergency Medical Services (p = 0.0040; 95%CI: -0.0816 - -0.0162) and a reduction in the level of 2.89 deaths per 100,000 inhabitants (p = 0.0001; 95%CI: -4.3293 - -1.4623), both with statistical significance. Regarding the control region, Baixada Santista, the difference in the result trend between intervention outcome and post-intervention control of -0.0639 deaths per 100,000 inhabitants was statistically significant (p = 0.0031; 95%CI: -0.1060 - -0.0219). We cannot exclude confounders, but we limited their presence in the study by including control region series.

CONCLUSIONS

Although the analysis of interrupted time series has limitations, this modeling can be useful for analyzing the performance of policies and programs. Even though the intervention studied is not a condition that in itself implies effectiveness, the latter would not be present without the former, which, integrated with other conditions, generates a positive result. SAMU is a strategy that must be expanded when formulating and consolidating policies focusing on emergency care.

Do cardiovascular disease prevention programs in northern Sweden impact on population health? An interrupted time series analysis

BACKGROUND

Cardiovascular disease (CVD) is the main cause of morbidity and mortality in Sweden. This study aims to assess the impact of a CVD intervention implemented in 1993 in northern Sweden on the reduction of premature ischemic heart disease (IHD) morbidity and mortality in women and men during the period 1987-2013.

METHODS

An ecological controlled interrupted time series design, with pre-intervention period defined as 1987-1993 and post-intervention period 1994-2013 was carried out. For each year, IHD events, stratified by sex, were retrieved from national registers.

RESULTS

Impressive reductions on IHD premature morbidity and mortality were observed to a similar degree in both the intervention county and the other comparison counties across the last 27 years. Significant differences in the pre-post intervention trends indicating the intervention group had smaller reductions than expected from its pre-intervention trend and the trend of control counties were found among men for both IHD morbidity and mortality. A similar pattern was observed among women but without significant differences.

CONCLUSIONS

Taken together, the data do not support that the intervention has contributed to an additional reduction on IHD morbidity and mortality, above and beyond that which is already seen in neighbouring counties without similar programs.

The effect of cardiorespiratory fitness assessment in preventive health checks: a randomised controlled trial

Background

Poor cardiorespiratory fitness (CRF) increases morbidity and mortality risks. Routine CRF assessment in clinical practice has thus been advocated, but little is known about the effect. In this study, we investigated the effect of CRF assessment on CRF in a preventive health check programme.

Methods

We used a randomised design, in which we invited 4153 middle-aged adults and included 2201 participants who received a preventive health check with CRF assessment (intervention) or without CRF assessment (control). After 1 year, participants were examined. The primary outcomes were adjusted absolute (l/min), relative (ml/kg/min), and poor (%) CRF assessed by the Astrand-Ryhming test. We adjusted for baseline physical activity and intra-cluster correlation within general practices.

Results

A total of 901 attended the 1-year follow-up. In the intervention group, absolute CRF, relative CRF, and poor CRF were 2.7 l/min (95% confidence interval [CI]: 2.6; 2.8), 34.5 ml/kg/min (95% CI: 33.5; 35.4), and 31.0% (95% CI: 26.8; 35.2). In the control group, the corresponding figures were 2.8 l/min (95% CI: 2.7; 2.9), 35.2 ml/kg/min (95% CI: 34.2; 36.1), and 25.9% (95% CI: 21.8; 30.0). Adjusted absolute CRF was lower in the intervention group (-0.1 l/min [95% CI: -0.2; -0.01]). Adjusted relative CRF (-0.7 ml/kg/min [95% CI: -2.0; 0.6]) and poor CRF (5.0% [95% CI: -0.002; 10.1]) did not differ between groups. No differences were found when adjusting for potential confounding factors.

Conclusion

Preventive health checks with CRF assessment did not provide higher CRF levels at 1-year follow-up than preventive health checks without CRF assessment.

Allostatic load as a predictor of all-cause and cause-specific mortality in the general population: Evidence from the Scottish Health Survey

Allostatic load is a multiple biomarker measure of physiological ‘wear and tear’ that has shown some promise as marker of overall physiological health, but its power as a risk predictor for mortality and morbidity is less well known. This study has used data from the 2003 Scottish Health Survey (SHeS) (nationally representative sample of Scottish population) linked to mortality records to assess how well allostatic load predicts all-cause and cause-specific mortality. From the sample, data from 4,488 men and women were available with mortality status at 5 and 9.5 (rounded to 10) years after sampling in 2003. Cox proportional hazard models estimated the risk of death (all-cause and the five major causes of death in the population) according to allostatic load score. Multiple imputation was used to address missing values in the dataset. Analyses were also adjusted for potential confounders (sex, age and deprivation). There were 258 and 618 deaths over the 5-year and 10-year follow-up period, respectively. In the fully-adjusted model, higher allostatic load (poorer physiological ‘health’) was not associated with an increased risk of all-cause mortality after 5 years (HR = 1.07, 95% CI 0.94 to 1.22; p = 0.269), but it was after 10 years (HR = 1.08, 95% CI 1.01 to 1.16; p = 0.026). Allostatic load was not associated with specific causes of death over the same follow-up period. In conclusions, greater physiological wear and tear across multiple physiological systems, as measured by allostatic load, is associated with an increased risk of death, but may not be as useful as a predictor for specific causes of death.

NHS Health Check comorbidity and management: an observational matched study in primary care

BACKGROUND

The NHS Health Check programme completed its first 5 years in 2014, identifying those at highest risk of cardiovascular disease and new comorbidities, and offering behavioural change support and treatment.

AIM

To describe the coverage and impact of this programme on cardiovascular risk management and identification of new comorbidities.

DESIGN AND SETTING

Observational 5-year study from April 2009 to March 2014, in 139 of 143 general practices in three clinical commissioning groups (CCGs) in east London.

METHOD

A matched analysis compared comorbidity in NHS Health Check attendees and non-attendees.

RESULTS

A total of 252 259 adults aged 40-74 years were eligible for an NHS Health Check and, of these, 85 122 attended in 5 years. Attendance increased from 7.3% (10 900/149 867) in 2009 to 17.0% (18 459/108 525) in 2013 to 2014, representing increasing coverage from 36.4% to 85.0%. Attendance was higher in the more deprived quintiles and among South Asians. Statins were prescribed to 11.5% of attendees and 8.2% of non-attendees. In a matched analysis, newly-diagnosed comorbidity was more likely in attendees than non-attendees, with odds ratios for new diabetes 1.30 (95% confidence interval [CI] = 1.21 to 1.39), hypertension 1.50 (95% CI = 1.43 to 1.57), and chronic kidney disease 1.83 (95% CI = 1.52 to 2.21).

CONCLUSION

The NHS Health Check programme provision in these CCGs was equitable, with recent coverage of 85%. Statins were 40% more likely to be prescribed to attendees than non-attendees, providing estimated absolute benefits of public health importance. More new cases of diabetes, hypertension, and chronic kidney disease were identified among attendees than a matched group of non-attendees.