Background
Amid improvements in cardiovascular disease (CVD) related mortality, risk factors remain high in adult Australians. Age-adjusted case fatality rates from CVD have fallen from 55% of all deaths in the late 1960s to 34% in 2007 [
1]. This is attributable to better CVD prevention, detection and clinical management. Nevertheless, CVD (notably coronary heart disease) ranks second highest in healthy years of life lost, representing 16% of the overall disease burden [
1]. Inevitably, the burden of CVD will inexorably rise within Australia’s ageing population [
2]. Despite some encouraging trends in respect to the declining prevalence of major risk factors [
1,
3], there are equally cautionary data in respect to sustained, and in some cases increasing levels of hypertension [
4,
5], dyslipidaemia [
1,
6] and metabolic risk factors (e.g. physical inactivity/sedentary behavior[
1] and obesity [
3,
7]). When coupled with increasing longevity, it is therefore imperative that heart health be improved by mitigating elevated risk factors [
8] through pharmacological and/or non-pharmacological recommendations embedded within evidence-based guidelines.
Any focus on reducing cardiovascular risk levels has to consider higher risk populations. People living in regional, rural or remote locations consistently fare worse than their metropolitan counterparts [
5,
9,
10] with mortality rates rising in accord with remoteness [
1]. Unfortunately, reliable (measured) population data, especially for biomedical health risk factors, are over 10 years old and limited in respect to regional data. This extends to the AusDiab Study and local Crossroads Undiagnosed Disease Study. Therefore, the overall aim of the
Healthy Hearts Beyond City Limits program was two-fold; firstly to confirm elevated levels of cardiovascular risk in key regional Victorian communities according to age and sex and to simultaneously determine the scope to engage such communities and individuals to reduce elevated levels of risk (if confirmed) through regional risk management clinics.
Discussion
The Healthy Hearts Beyond City Limits program, involving over 2,000 adults from four diverse regional locations, is the largest surveillance study of CVD-related risk factors and associated lifestyle and health behaviors utilizing measured results in regional Victoria, Australia. Overall, high levels of risk factors for CVD were common in all age groups. The proportion of participants outside individualized recommended levels ranged from 68% for elevated LDL-C to 11% for smoking, with abnormal cholesterol levels, raised BP and excess weight affecting half of participants. Younger adults more frequently reported smoking and increased alcohol consumption as well as depressive symptoms, the latter being more evident in women from most regional communities. Independent of regional location, men lagged behind women in many CVD risk indicators. Alternatively, more women were obese and physically inactive. Inter-community differences were evident with participants from the larger community and surrounding areas of Geelong having more favorable risk profiles compared to Colac who had the worst, yet those living in Shepparton were more obese and had excess alcohol consumption. High levels of risk confirmed a persistent problem in these communities. Alternatively, high levels of engagement reaffirmed the potential value of an extended program combining surveillance and active prevention.
The unadjusted prevalence of elevated BP, TC and LDL-C observed in this cohort was substantially higher than previous reports [
9,
10,
36,
37] but probably reflects participant self-selection and application of individualized (treatment) targets. Our older study cohort may partially, although not completely, explain the higher proportion of hypertension found in the rural Greater Green Triangle Risk Factor Study [
37]. Alternatively, it is possible that BP levels are rising [
5]. In the absence of (representative) population data, it is difficult to truly quantify the problem of elevated BP in regional Victorians. The (predominantly urban) AusDiab study found a lower prevalence of elevated TC [
9] based on a cut-off of 5.5 mmol/L, but in the absence of regional differentials, there are no recent population data to compare our findings to assess whether they parallel national declining trends in primary care [
6] and indeed global patterns [
38]. Equally concerning were the high rates of overweight and obesity, a trend now seen world-wide [
39]. Compared to contemporary regional estimates (78% for men and 52% for women) [
3], our findings were slightly lower for men yet higher for women and generally overestimated compared to state statistics [
10]. However, other studies have relied upon self-reported and therefore underestimated BMI [
40]. Of concern, one in four adults reported depression. This appeared higher than the latest population estimates but confirmed that women were more likely affected than men [
9]. In the latest National Health Survey, regional Australians were 16% more likely to report a mental health problem [
41].
Despite highly prevalent CVD risk factors, absolute CVD risk scores were not congruently elevated emphasizing the well known limitation of risk classification for “low risk” who demonstrate coronary atherosclerosis [
42]. Unfortunately, the introduction of new biomarkers [
43] and non-invasive tests [
42] are yet to improve the predictive ability of risk equations in asymptomatic individuals from a practical perspective. The end point of what to predict (e.g. CVD or coronary heart disease) also remains vague [
42] yet Australian guidelines advocate for a composite CVD risk score [
20] to identify individuals who may benefit from preventative therapy. All participants in the
Healthy Hearts program, regardless of absolute CVD risk levels, were counseled on recommended risk factors levels and ideal diet and lifestyle behaviors or pharmacological treatment (if necessary). Exploring individuals’ present risk factors and future CVD risk was highly engaging with strong potential for significant risk reduction at earlier stages across the spectrum of CVD.
An individual’s risk of illness cannot be considered in isolation from their wider community. We observed heterogeneity in respect to the risk profiles of individuals in the different communities. This undoubtedly reflects the differentials of the socio-demographic profiles of participants but also reflects the differences in the characteristics of the broader communities in which these individuals lived. This includes the size, geographic location and level of local health care services. At the individual level, older communities will likely have elevated BP levels, and places with reduced access to a healthier and cheaper food supply might have higher levels of metabolic disturbances. As such there is likely to be considerable heterogeneity in the specific risk profile and health care needs of regional communities, requiring adaptation of services at their local level. Overall, Australia’s ageing population has resulted in significant retirement migration from urban to regional areas. Simultaneously, the closure or down-grading of local hospitals to aged care centers has created a mismatch between the supply and demand for regional health care services. Specialist cardiac services are scarce and few cardiologists practice in non-metropolitan areas [
41]. The burden of health care is predominantly transferred to regional primary care services [
41] where there are 87 full time equivalent GPs/100,000 population compared to 98 in major cities [
44]. Financially stimulated growth in regional GP numbers has been offset by reduced operational hours [
44]. Ominously, regional Australians are more likely to die from ischaemic heart disease (44%) or stroke (31%) than those living in major cities [
41] with even worse differentials for fatal hypertensive heart disease (90% more likely) and heart failure (70%) events.
These data underlie the potential value of regional risk clinics to support already stressed primary care services. Encouragingly, the degree of individual and community engagement in the Healthy Hearts program exceeded expectations. Participating individuals overcame barriers to limited access to health care that is typical of regional community life and this program provides the impetus to establish cost-effective community-based risk management clinics. This was the focus of the soon to be reported Protecting Healthy Hearts program undertaken in regional Victoria, Australia.
There are a number of important limitations which may influence the interpretation and generalizability of our findings. Given limited resources we selected higher risk communities and participants were self-selected resulting in age and gender differences compared to population estimates in some communities (refer Figure
1). Self-selection potentially introduced further bias towards those with higher levels of risk, albeit the proportion of smokers (11%) we found was reduced compared to national population surveys (18%) [
1], possibly due to our older cohort and the trend of decreased smoking prevalence with age. We measured lipid profiles in the non-fasting state in many participants (93%) based on findings that levels of TC, LDL-C, HDL-C, TC to HDL-C ratio and triglycerides are minimally affected by normal food intake in individuals in the general population [
45]. It is also unlikely that the lipid profile response to typical food intake would vary according to sample timing. We cannot discount seasonal weather confounders and extraneous factors such as drought and floods which might particularly affect farmers.
Acknowledgement
The Rotary Club of Melbourne is sincerely thanked for their endearing commitment to the program and their fundraising efforts to provide the mobile assessment unit and project supplies. The organizing committees and program co-coordinators from the Rotary Club of Colac, the Rotary Club of Bairnsdale, the Rotary Club of Shepparton and the Rotary Club of Geelong are gratefully acknowledged. The authors wish to thank all nurses, students and research staff who assisted with the screening assessments, data collection and ECG interpretation. Much appreciation also goes to the data management team for their processing of an abundance of paperwork.
All authors are supported by the National Health and Medical Research Council of Australia. Healthy Hearts was supported in part by the Victorian Government’s Operational Infrastructure Support Program.
This work was supported by a competitive research grant from the Australian Rotary Health Research Fund, the Alison Bult bequest, raised funds by the Rotary Club of Melbourne and philanthropic funding from Perpetual Philanthropic Services, George Adams Tattersalls Foundation, Goldman Sachs JB Were Foundation and the Windermere Foundation Limited.
Competing interests
The authors declare that they have no competing interests.
Authors’ contributions
MC participated in the design, co-ordination and data collection of the study, carried out the analyses and interpretation of the data and drafted the manuscript. GJ participated in the conception and design of the study. RC participated in the design of the study. SS conceived of the study, participated in the design, co-ordination and data collection and contributed to analyses and interpretation of the data. GJ, RC and SS were involved in revising the manuscript critically for important intellectual content. All authors read and approved the final manuscript.