MI rate fell nearly 75% in London cohort during 20-year period

Hardoon S. Eur Heart J. 2011;doi:10.1093/eurheartj/ehr142.

Issue: July 2011

From 1985 to 2004, the rate of MI among participants of a cohort in London decreased 74%, with declining non-HDL cholesterol levels and increased HDL cited as the main reasons for the decline. However, the study, appearing in the European Heart Journal, also found that rising BMI could potentially reverse the trend in the future.

The researchers performing the study looked at men (n=6,379) and women (n=3,074) from the Whitehall II cohort. All participants were from 20 civil service departments in London between 1985 and 1988, aged 35 to 55 years and had clinic visits every 5 years. Participants completed questionnaires and examinations on health and lifestyle during four periods: 1985 to 1988, 1991 to 1993, 1997 to 1999 and 2002 to 2004.

During the 20 years, 256 first MI events were reported, of which 81.3% occurred in men. The age-sex adjusted hazard for MI decreased by 74% (95% CI, 48-87) during this time, which corresponded to a mean decline of 6.5% (95% CI, 3.2-9.7) per year.

According to the researchers, 56% of this decline could be attributed to percent decreases in non-HDL levels (34%), systolic BP (13%) and cigarette smoking (6%), as well as increases in HDL levels (17%) and fruit and vegetable consumption (7%). Also noteworthy, rising BMI reduced the scale of the decline by 11%.

These findings, the researchers wrote, highlight what can be achieved and emphasize the value of measures to reduce exposure to risk factors in the population.

“Further research is needed to determine whether the residual unexplained portion of the decline in MI may be explained by early treatment, underestimated contributions of the major risk factors (reflecting imprecision in the analyses) or the influence of other risk factors,” they said, while adding that the rising BMI in the UK and other countries still needs urgent attention.

Follow CardiologyToday.com on Twitter.