Several large scale community based cardiovascular disease (CVD) prevention programs were initiated in the late 80s including Minnesota and Pawtucket in US, North Karelia in Finland, Heartbeat Wales in UK and the Västerbotten Intervention Program (VIP) in Sweden. These programs have generated extensive and rich research, and VIP alone has been the source for hundreds of scientific articles. However, there is a striking absence of health economic perspectives in these publications. We have searched PubMed using different combinations of terms such as “cost-effectiveness” and “community based CVD prevention”, and found only six publications [1,2,3,4,5,6], (all from 1997 or earlier). One report that was based on the VIP [6] used intermediate measures, such as changes in cholesterol and blood-pressure, to predict eight-year cumulative incidence of coronary heart disease using a Framingham risk equation. From a societal perspective, the results ranged between savings and a cost of 1950 £ per year of life gained.
In general, a cost-effectiveness analysis requires endpoint data such as changes in morbidity and/or mortality, and these data can either be collected directly or modelled based on intermediate outcomes, e.g. changes in blood pressure or smoking habits. Neither of the routes are, however, easily accessible.
Effectiveness assessment based on impact on morbidity and mortality presuppose a sustainable intervention, a structure in place which enables long-term follow up, and a sufficiently large scale to be able to measure impact on rare events such as mortality. These prerequisites require a patient funder who is willing to support an intervention for a decade or more prior to seeing any tangible returns. Against this background, the concept of “modeling for decision-making” has become popular. This involves predicting final outcomes on the basis of intermediate ones by applying the philosophy of evidence based medicine; to use the best available data when you are forced to make a decision. Among the advantages of this methodology are the relatively low cost and timeliness. Decision-makers therefore receive a relatively prompt answer, and do not risk funding an intervention for a decade that in the end turns out to be worthless. Modelling also has its disadvantages, and Burgers et al. [7] have recently completed a review of the traps encountered when creating models in the field of CVD. In summary, they argue that many models lack validity because appropriate data are not available.
Fortunately, VIP is one of the few community-based CVD programs that meet all the criteria discussed above for making an economic analysis based on end-points feasible. Such a publication would fill two gaps in the literature: a) the absence of studies from the last 20 years and b) the absence of studies based on empirically confirmed mortality.
Aim of the study
To estimate the costs of running VIP from 1990 to 2006, versus the health gains and savings reasonably attributable to the program during the same time period.
Setting - Västerbotten intervention programme
Coronary heart disease mortality started to gradually increase in Sweden starting in the early 1900s. This trend occurred more slowly in northern Sweden and was not noted until the 1940s. Epidemiological studies from the 1970s showed that Västerbotten County had the highest age-adjusted CVD mortality rate in Sweden (ages 15 to 74) and that this rate was 40% higher than the county with the lowest mortality.
In response to these alarming epidemiological reports, in 1984 the Västerbotten County Council decided to develop a model for a long term population-oriented program for the prevention of both cardiovascular disease and diabetes. The program was based on integrated cooperation within local communities with primary health care as the coordinating hub.
As an initial step in 1985, a pilot study was introduced in the Norsjö municipality that combined individual disease prevention efforts among the middle-aged population with community-oriented health promotion activities. All citizens at 30, 40, 50, and 60 years of age were invited to a physical examination combined with a healthy dialogue at the local primary health care centre. A 10-year evaluation showed that the age- and education-adjusted CVD mortality risk, based on the North Karelia CHD risk equation, was reduced by 36% in Norsjö, compared to a 1% reduction in the reference area (Northern Sweden MONICA Study). This risk reduction was found to have occurred primarily in the low education group [8].
Based on experience from the pilot study, the core intervention concept ─ physical examination, survey, and health dialogue ─ was implemented in all the county’s municipalities during the early 1990s. This collective effort became known as the Västerbotten Intervention Programme (VIP). A detailed description of the design of the VIP, CVD risk factor measurements and questionnaire data, support of primary care providers, and development according to medical evidence, has been published previously. VIP was included in the regular Västerbotten primary care mission from 1995 [9].
During the 17 years (1990–2006) reported in this study, the participation rate gradually increased from about 55 to 65%, with only small socio-economic differences between participants and non-participants [10].
The VIP-intervention: Individual health dialogue
Nurses provided feed-back to participants based on the results of CVD risk factor measurements, health, lifestyle habits, and socioeconomic and psychosocial factors. Initially, this occurred in a unidirectional fashion with the nurse lecturing the participant. Gradually, however, this communication was developed into a dialogue, based on the concept of motivational interviewing. The participant’s risk profile was visualized in the shape of a star, where greater risk was indicated by blunt tips and a low risk was shown as a star with sharp tips. This pedagogical tool is aimed at facilitating the understanding of relationships between life style habits and CVD risk factors. The goal was to motivate the participants with a low risk factor burden to maintain healthy habits, and to support and motivate those with multiple risk factors to modify their behaviour. If appropriate, follow-up visits or referral to the family physician (usually a GP) for further evaluation and treatment was recommended.
Risk factor monitoring
According to published reports, from 1990 to 2007 smoking prevalence among VIP participants significantly decreased both for men and women [11]. The general trend of increasing obesity has slowed, the prevalence of hypercholesterolemia [12] and hypertension [13] have significantly decreased, and the level of physical activity has increased [14]. Over half of the participants with poor self-reported health at base-line have, at the 10-year follow up, reported improved self-reported health [15]. However, at the 10-year follow up, the average level of fasting glucose has increased by 0.5 mmol/L, which is also reflected in an increase in diabetes prevalence, especially among men [16]. Among VIP participants, there is a significant difference in risk factor burden between educational levels.