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Patients who have a myocardial infarction (MI) are at significantly increased risk of developing other serious long-term health conditions, according to a new study from the University of Leeds.
The research, published in the journal PLOS Medicine, analysed the records of all individuals aged 18 years and over admitted to one of 229 NHS trusts in England between 1 January 2008 and 31 January 2017 – the largest study of its kind.
This amounted to 145,912,852 hospitalisations among 34,116,257 individuals, with 433,361 reports of people with first-time MI. The average age of patients with MI was 67 years, and 66% of these patients were male.
The study looked at 11 non-fatal health outcomes, plus all-cause mortality, within the nine-year study period and compared the results to a control group of 2,001,310 individuals.
Patients who had an MI went on to develop further conditions at a much higher rate when compared to the control group of patients of the same age and sex who had not had one, with the exception of dementia and cancer.
Adverse health events following MI
Following MI, the most frequent event was all-cause mortality at 37.8% in the study group compared with 35.3% of the control group.
The most likely health outcome washeart failure, with 29.6% of the study group going on to develop the condition within nine years of their MI, compared with 9.8% of the control group over the same period.
Kidney failure developed in 27.2% of the patients in the study group, compared with 19.8% of the control group, while 22.3% of the study group went on to develop atrial fibrillation, compared with 16.8% of the control group.
In addition, new hospitalisation for diabetes was seen in 17% of the study group, compared with 14.3% of the control group.
When it came to mental health, the researchers found the hospitalisation records indicated depression occurred in 8.9% of people – which was 6% more likely following a MI than in the control group.
Women were more likely to develop depression after an MI than men, especially those who experienced it at a younger age. Some 21.5% of women who were under the age of 40 at the time of their mi had hospitalisation records for depression compared with 11.5% of men in the same age category.
The study also found that people from more socioeconomically deprived backgrounds were more likely to die or develop serious long-term health conditions following MI – in particular heart and kidney failure – compared to people from less deprived backgrounds of a similar age.
Dementia and cancer risk
However, there was no overall difference in the risk of dementia following a MI compared with the control group. Whilst the risk of vascular dementia was more likely in the study group, the difference observed was small at 2.3% in the study group and 2.1% in the control group.
The research also showed that cancer was less pronounced in the study group than in the control group. Some 13.5% of the study group went on to develop cancer after their MI, compared with 21.5% of the control. However, the researchers stated that there are many likely factors affecting this finding and that the specific reasons ‘remain unclear and require further investigation’.
Morag Foreman, head of discovery researchers at Wellcome, which part funded the study alongside the British Heart Foundation, said: ‘As survival rates following a myocardial infarction improve, understanding the longer-term impacts on physical and mental health is crucial.
‘This research shows how cohort studies and analysis of large data sets can further our understanding of key health challenges and demonstrates the value to supporting discovery research in the field of population and public health.’
Individual care plans for MI
The researchers noted that as the study included only secondary care data, there is potential for an underestimation of the total burden of disease following MI as diagnoses may be made in other settings.
Nevertheless, with around 1.4 million MI survivors in the UK who are at high risk of developing further serious health conditions, lead author Dr Marlous Hall, associate professor of cardiovascular epidemiology at the Leeds School of Medicine and Multimorbidity Research in the Leeds Institute for Data Analytics, said the study ‘highlights the need for individual care plans to be revised to take into account the higher demand for care’.
She added: ‘Our study provides accessible online information of the risk of these health outcomes for specific age, sex and socioeconomic deprivation groups so that individuals surviving a heart attack can be well informed about their future risks, in order to support informed healthcare decision making with their doctor.
‘Effective communication of the likely course of disease and risk of adverse long-term outcomes between patients and healthcare professionals can promote positive lifestyle changes, encourage patients to stick to treatment, and improve patient understanding and quality of life.’
In 2023, a genetic study revealed that the use of clopidogrel in British patients of south Asian ancestry was less effective at preventing recurrent MI than in those of European descent.
