While England’s national death rate from coronary heart disease has been dropping steadily for nearly 2 decades – and by two-fifths in the last decade alone – stubborn disparities have remained along local lines, with some areas proving consistently worse off relative to others.

Findings published online Nov. 10 in JAMA suggest that although most factors associated with coronary heart disease (CHD) deaths lay in locally varying population characteristics such as smoking, ethnicity, and socioeconomic deprivation, areas that recorded a lower prevalence of hypertension saw higher CHD mortality rates, too – possibly because health services were being underused or some local primary care trusts were diagnosing and managing this CHD risk factor more effectively than others.

In short, “your post code may affect your chances of dying of coronary heart disease,” the study’s lead author Dr. Louis S. Levene of the University of Leicester (England) said in an interview. The study, which examined publically available data for 2006, 2007, and 2008, covered England’s total population of about 54 million (JAMA 2010;304:2028-34).

Using a hierarchical regression model, Dr. Levene and his colleagues sought to examine the relationship between variations in coronary heart disease mortality among England’s 152 local primary care trusts and differences in any potentially explanatory factors associated with the populations they served and the delivery of health services. In 2008, the national age-standardized CHD mortality rate was 88.4/100,000 population in England (down from 97.9 in 2006 and 93.5 in 2007). Among individual local trusts, the age-standardized CHD mortality varied between 45.3 and 147.1/100,000.

The final model derived from the analysis explained about two-thirds of the variation in CHD mortality, consistent across the 3 years studied. In this model four of the five factors shown to correlate with higher local CHD mortality were population based: trusts with more white people (when examined independently of other risk factors), greater socioeconomic deprivation, more smokers, and more people with diabetes. This, Dr. Levene said, was not entirely a surprise.

The investigators also identified, however, an important service-related factor in trusts with higher CHD mortality, also consistent in the 3 years: less diagnosis of hypertension. This explained about 10% of the variation.

For example, while the Health Survey for England, an annual population study designed to measure health and health-related behaviors, saw rates of diagnosed and expected prevalence levels of diabetes that were very close in 2008, Dr. Levene and his colleagues saw a significant disparity the same year with hypertension. Only 13% of England’s population was recorded on practice registers as having hypertension, they noted, “although the Health Survey for England found a prevalence of hypertension of 30.1% among adults.”

Dr. Levene said he did not know whether to ascribe the gap to underutilization of health services or a failure of the trusts to deliver preventive care. “A standard GP appointment lasts 10 minutes,” he said in an interview, which may mean blood pressure checks are not done even though they are recommended by guidelines. “In my practice we have 13,000 patients – if someone comes in to see you for depression, we may try and remember to do [blood pressure],” he said. “People are getting better at doing it, since rates of diagnosis are going up.”

Dr. Levene and his colleagues noted some of the limitations of their study, which included the possibility of having omitted or neglected potentially relevant factors, such as access to or continuity of health services. One missing potential population variable was sex, they wrote, “because the age-standardized CHD mortality rates are higher in men than in women.” No other variables used were sex specific, so the effect of sex could not be analyzed.

Nonetheless, the investigators wrote, the findings had several policy implications. “Programs to reduce [CHD] mortality should address those characteristics of populations amenable to intervention, including smoking and deprivation. The importance of paying attention to population characteristics is emphasized by the finding that better detection of hypertension in the population was associated with reduced CHD mortality at the population level.”

“My personal view,” Dr. Levene told this news organization, “is that if collectively we become more interested in primary prevention in the wider population, this rate of decline should continue and the gaps should narrow.”

The study was funded through the National Institute for Health Research. One of Dr. Levene’s coauthors, Dr. Kamlesh Khunti, reported being an adviser to the National Screening Committee and a clinical adviser for the Diabetes NICE-led Quality and Outcomes Framework Panel. No other authors reported any financial disclosures.

Copyright (c) 2010 Elsevier Global Medical News. All rights reserved. This material may not be published, broadcast, rewritten, or redistributed.

据11月10日在线发表于《美国医学会杂志》(JAMA)的一项研究，英国境内的冠心病(CHD)死亡率在过去近20年中稳步下降(单在过去10年就下降了40%)，但某些局部地区的冠心病发病率却仍在持续恶化中。

本研究对2006~2008年间公开发布的数据进行了分析，数据涵盖了英国境内的全部居民(总计5,400万)。研究者使用层次回归分析对英国境内152所地方性初级保健信托机构(PCT)患者CHD死亡率间存在的差异及每所PCT所辖人群潜在致病因素间的差异进行了调查。

在2008年，英国全国年龄标准化CHD死亡率为88.4例/10万人(该数据在2006年和2007年分别为97.9例和93.5例/10万人)，而地方性PCT在该指标上的变化幅度介于45.3~147.1/10万之间。最终回归模型可解释CHD死亡率全部变异度的2/3，且该指标在3个不同研究年份间保持一致。致使局部地区CHD死亡率增高的5大危险因素中有4个是基于人群的：PCT中白种人患者比例较高，患者的社会经济学地位较低下，吸烟者比例较高及糖尿病患者比例较高。

研究者发现，某PCT患者的高血压诊断率越低，其CHD死亡率就越高，该因素是与PCT卫生服务质量相关的重要危险因素，可以解释整个CHD死亡率变异度的10%。据英国国民健康调查(HSE)的数据估测，英国成人高血压的发病率约为30.1%，但同期医疗保健机构有记录的高血压患者数仅占英国总人口的13%。

研究的局限性在于其没能对一些相关因素进行分析，比如患者至PCT就诊和获得持续性卫生服务的几率。另外，受所用数据的限制，研究未能就性别因素进行单独分析。

鉴于地区间CHD死亡率主要受人群因素的影响，政府应制定政策对相关人群因素加以干预。此外，各PCT应努力提高卫生服务质量，全科医师应按指南要求，将血压测量作为诊疗常规加以执行。

本研究由英国国家健康研究院赞助。其中一位共通作者披露供职于多家机构。其余作者表示无任何经济利益冲突。