Heart disease and the environment

Acute coronary syndromes related to bio-climate in a Mediterranean area. The case of Ierapetra, Crete Island, Greece

The occurrence of non-fatal acute coronary syndromes (ACS) is examined in relation with the local bioclimatic conditions in the Ierapetra area, in the southernmost part of Crete Island, Greece, during the period 2004-2007. Daily ACS counts and corresponding meteorological parameters, such as maximum and minimum air temperature, relative humidity, wind speed and cloudiness, were analyzed. Besides, the daily values of the human thermal index, physiologically equivalent temperature (PET) was evaluated. Pearson's χ(2) test and generalized linear models (GLM) with Poisson distribution were applied. The ACS syndromes present a multiple variation within the year, with the primary maximum in August and the secondary in May, while relative high ACS frequencies exist in early winter time. The impact of the weather variability on the ACS incidence is not statistically significant (C.L. 95%).

Climatological variations in daily hospital admissions for acute coronary syndromes

OBJECTIVE

We examined the association between climatologic parameters and daily admissions for non-fatal acute coronary syndromes (ACS) to emergency units of hospitals in the greater Athens area, from January 2001 to August 2002.

METHODS

Daily mean, maximum and minimum temperatures, relative humidity, wind speed, barometric pressure and a thermo-hydrological index (T.H.I.) were measured at the meteorological station of the Laboratory of Climatology of the Geology Department of the University of Athens. In addition, the daily number of admissions for acute myocardial infarction or unstable angina in the five major general hospitals in the greater Athens area was recorded. Generalized additive models (GAM) were applied to regress-time-series of daily numbers of outpatients with acute cardiac events against climatological variations, after controlling for possible confounders and adjustment for over dispersion and serial correlation.

RESULTS

Five thousand four hundred fifty-eight Athenians with non-fatal acute cardiac events were admitted to the selected hospitals during the period of the study, 4093 (75%) males and 1365 (25%) females. There was a negative correlation between hospital admissions and mean daily temperature (MDT) with a 1 degrees C decrease in mean air temperature yielding a 5% increase in hospital admissions (P<0.05). This association was stronger in females and the elderly (P<0.01). Relative humidity was positively correlated with hospital admissions (P<0.05).

CONCLUSION

Despite the relatively short study period (<2 years), these findings suggest a significant association between cold weather and increased coronary heart disease incidence, especially in the elderly and females.

Prenatal diagnosis of congenital heart disease

Owing to the widely different levels of experience of examiners, there is a large discrepancy in study results of second trimester ultrasound screening for fetal malformations, which is a result of varying levels of obstetric scanning expertise prevalent at the reporting centre. This holds particularly true for the prenatal diagnosis of congenital heart disease where detection rates ranging from 0 per cent to 60 per cent are being reported. On the other hand, congenital heart disease affects about 4-8 per 1000 live births and is a leading cause of infant mortality, whereas prenatal diagnosis could possibly prevent death and long-term morbidity in some of these neonates. Various screening concepts for more effective detection of congenital heart diseases are analysed in this article, including the more recent technique of early echocardiography between 13 and 15 weeks of gestation. High-risk groups are defined and the group of fetuses with increased thickness of nuchal translucency seems to be of particular interest.

Epidemiology of congenital heart disease in the United States

Data from the National Center for Health Statistics were examined to aid in assessing the burden of congenital heart disease in the United States. In 1979 through 1988 combined, 46,450 deaths were attributed to CHD, 26,319 occurring in the first year of life. Another 14,283 deaths were attributed to other congenital anomalies of the circulatory system. In 1988 through 1990 combined, there were > 300,000 hospital discharges with any diagnosis of CHD, with 2.7 million days of care provided. For infants aged < 1 year, the rate was 13.7 per 1000 live births per year. Another 242,049 discharges had any diagnosis of other congenital circulatory anomalies. In 1983 through 1985, > 700,000 persons reported a history of CHD. In 1989, heart malformations were reported on the birth certificate of 4621 live births in 45 states and the District of Columbia. In 1988 through 1990 there were an estimated 37,445 repairs of atrial and ventricular septa. In addition, 45,635 cardiac catheterizations were performed in patients aged < 5. Average annual percentage declines in infant mortality rates for the period 1979 through 1988 were consistent with an effect of improvements in surgical technique and intensive care. The average annual infant mortality rate for hypoplastic left heart syndrome increased 1.3%, and rates for five causes amenable to treatment such as transposition of great vessels declined. Infant mortality rates in nonmetropolitan areas were higher than in metropolitan areas, suggesting that limited access to care might be associated with mortality.(ABSTRACT TRUNCATED AT 250 WORDS)