Effect of screening and lifestyle counselling on incidence of ischaemic heart disease in general population: Inter99 randomised trial
BMJ 2014; 348 (Published 9 June 2014)

Abstract
Objective
To investigate the effect of systematic screening for risk factors for ischaemic heart disease followed by repeated lifestyle counselling on the 10 year development of ischaemic heart disease at a population level.
Design Randomised controlled community based trial.

Setting Suburbs of Copenhagen, Denmark

Participants 59?616 people aged 30-60 years randomised with different age and sex randomisation ratios to an intervention group (n=11?629) and a control group (n=47?987).

Intervention
The intervention group was invited for screening, risk assessment, and lifestyle counselling up to four times over a five year period. All participants with an unhealthy lifestyle had individually tailored lifestyle counselling at all visits (at baseline and after one and three years)

; those at high risk of ischaemic heart disease, according to predefined criteria, were furthermore offered six sessions of group based lifestyle counselling on smoking cessation, diet, and physical activity.

After five years all were invited for a final counselling session. Participants were referred to their general practitioner for medical treatment, if relevant.
. The control group was not invited for screening.

Main outcome measures
The primary outcome measure was incidence of ischaemic heart disease in the intervention group compared with the control group. Secondary outcome measures were stroke, combined events (ischaemic heart disease, stroke, or both), and mortality.

Results 6091 (52.4%) people in the intervention group participated at baseline
. Among 5978 people eligible at five year follow-up (59 died and 54 emigrated), 4028 (67.4%) attended. A total of 3163 people died in the 10 year follow-up period.
. Among 58?308 without a history of ischaemic heart disease at baseline, 2782 developed ischaemic heart disease. Among 58?940 without a history of stroke at baseline, 1726 developed stroke

. No significant difference was seen between the intervention and control groups in the primary end point (hazard ratio for ischaemic heart disease 1.03, 95% confidence interval 0.94 to 1.13) or in the secondary endpoints (stroke 0.98, 0.87 to 1.11; combined endpoint 1.01, 0.93 to 1.09; total mortality 1.00, 0.91 to 1.09).

Conclusion
A community based, individually tailored intervention programme with screening for risk of ischaemic heart disease and repeated lifestyle intervention over five years had no effect on ischaemic heart disease, stroke, or mortality at the population level after 10 years.
Trial registration Clinical trials NCT00289237.

Systematic screening of the general population for high risk followed by lifestyle counselling has, in this large randomised population based study and in all previous similar studies, not been able to reduce the incidence of ischaemic heart disease.
Therefore, health checks with systematic screening and counselling cannot be recommended.
Lifestyle counselling should continue in everyday practice but should not be implemented as a systematic programme in the general population.

What is already known on this topic: G Mohan.
• Screening for risk factors for ischaemic heart disease (IHD) followed by lifestyle counselling leads to small changes in risk factors, but not to reduced mortality from IHD
• Trials have been criticised for lack of theoretical framework, spill over effects on the control group, insufficient intervention, and lack of intention to treat analyses
• Most trials have looked only at fatal cases among men
What this study adds
• Systematic screening and intensive lifestyle counselling had no effect on development of fatal and non-fatal IHD in the general population, in either women or men
• This study confirms that health checks followed by lifestyle counselling in a general population are not effective in reducing the burden of IHD in society and should not be part of a country’s health policy.

G Mohan.