Reflex testing I: algorithm for lipid and lipoprotein measurement in coronary heart disease risk assessment

We reviewed the current literature in order to construct a reflex testing algorithm that maximizes clinical utility and cost-effectiveness of lipid and lipoprotein testing. The algorithm was based on the 2nd Report of the National Cholesterol Education Program Adult Treatment Panel guidelines for use of total cholesterol (TC), triglycerides (TG), HDL-C, and LDL-C, and published reports describing the clinical use of apolipoprotein B and lipoprotein (a). The success of this algorithm was tested in a low-risk general and a high-risk hyperlipidemic patient population. Lipid data and non-lipid risk factors were obtained from a national database and from patients seen at two lipid clinics. A total of 16 968 individuals from the National Health and Nutrition Examination Survey III database comprised the low-risk group, and 239 patients examined in the Hartford Hospital and Washington University Lipid Clinics comprised the high-risk group. We found a solid scientific base to support the NCEP guidelines and reasonable support for limited testing of apoB and Lp(a). According to the algorithm, the direct LDL-C assay was deemed unnecessary in 98% and 91% of low- and high-risk subjects, respectively, if one assumes that the Friedewald equation is adequate with TG≤4.00 g/l. With a more conservative cutoff of TG≤2.50 g/l, the algorithm canceled 92% and 81% of direct LDL tests, respectively. The algorithm also limited TG to 20 and 64%, apoB to 6 and 20%, and Lp(a) to 15 and 56%, of low- and high-risk groups, respectively. Use of a comprehensive, reflex algorithm for coronary heart disease risk assessment will substantially reduce the utilization of laboratory services without diminishing the clinical value of these tests. The algorithm will prevent the overuse of certain expensive tests (direct LDL) while promoting the limited use of underutilized tests [apoB and Lp(a)].     

Estimation of physiologic ability and surgical stress (E-PASS) as a new prediction scoring system for postoperative morbidity and mortality following elective gastrointestinal surgery

(Received for publication on Oct. 25, 1997; accepted on July 7, 1998)     

Hypothesis: is low prenatal vitamin D a risk-modifying factor for schizophrenia?

The central nervous system is increasingly being recognised as a target organ for vitamin D via its wide-ranging steroid hormonal effects and via the induction of various proteins such as nerve growth factor. This paper proposes that low maternal vitamin D may impact adversely on the developing foetal brain, leaving the affected offspring at increased risk of adult-onset schizophrenia. The hypothesis can parsimoniously explain diverse epidemiological features of schizophrenia, such as the excess of winter births, increased rates of schizophrenia in dark-skinned migrants to cold climates, the increased rate of schizophrenia births in urban versus rural setting, and the association between prenatal famine and schizophrenia. Studies that will allow rejection of the hypothesis are proposed.     

Perinatal mortality trends in a referral hospital

A comparative study of perinatal mortality patterns over a period was conducted at a teaching hospital of South India. Among the 6,048 babies born from January 1984 to December 1985 (Group A), there were 265 (43.8/1000) still births and 127 (22.0/1000) early neonatal deaths. Three hundred and thirty seven (41/1000) babies were still born and 235 (29.8/1000) early neonatal deaths out of 8,215 deliveries during 1992–93 (Group B). The perinatal mortality rate (PMR) in Group A and B were 57.9/1000 and 57.7/1000 respectively. Unbooked cases accounted for the majority (> 75%) of perinatal deaths during both the periods. The overall mortality rates in unbooked cases were three to four times higher than booked cases. Among the various causes of still births, antepartum haemorrhage and uterine rupture had increased. Septicaemia was the major cause of early neonatal deaths in Group A, but in Group B birth asphyxia and prematurity were the leading causes. Effective interventions like creating awareness among the target population to utilise maternal and child health services and early referral of high risk cases with improved intranatal and perinatal care can decrease the perinatal mortality.     

Long-term lowering of blood pressure after carotid and vertebrobasilar ischemic stroke

We followed up 107 patients experiencing a first-ever ischemic stroke after having been affected by essential hypertension for at least one year, in order to analyze the phenomenon of post-stroke blood pressure lowering. Of the 82 patients still surviving after three months of follow-up, 44 (54%) had normal arterial blood pressure values. There were no significant differences between these normotensive patients and the 38 with high blood pressure in terms of cerebrovascular risk factors or disability, but blood pressure normalized in 34 of the 54 patients experiencing a carotid stroke (63%) and in only 10 of the 28 experiencing vertebrobasilar stroke (36%) (p=0.035). These data may offer a starting point for further studies of the neurogenesis of arterial hypertension.

---

Sommario Al fine di analizzare il fenomeno della normalizzazione della pressione arteriosa dopo ictus cerebrale in pazienti prima ipertesi, abbiamo osservato 107 soggetti con primo ictus ischemico, che erano già precedentemente affetti da ipertensione arteriosa da almeno un anno. Degli 82 (77%) sopravvissuti a tre mesi di follow-up, 44 (54%) hanno mostrato una normalizzazione della pressione arteriosa. L'incidenza di fattori di rischio per malattia cerebrovascolare e disabilità grave non è risultata significativamente diversa nel gruppo degli ipertesi rispetto ai normotesi. Tuttavia la normalizzazione della pressione arteriosa è stata osservata in 34 dei 54 pazienti con ictus carotideo (63%) e solo in 10 dei 28 con ictus vertebrobasilare (36%) (p=0.035). Riteniamo che tali dati offrano uno spunto per ulteriori ricerche sulla genesi neurogena dell'ipertensione arteriosa essenziale.

     

Appendicitis: Higher risk in Mexican Americans?

Objectives. Mexican Americans (MAs), compared to white non‐Hispanics (WNHs), have higher rates of biliary disease, noninsulin dependent diabetes, and endstage renal disease but lower rates of lung cancer, hip fractures, and mortality from coronary heart disease. Relatively little research has been done to identify other ethnic differences in disease incidence. We used surgical procedure rates to confirm known ethnic differences and to explore our clinical suspicion that MAs have higher rates of appendectomy than WNHs.

Methods. We used a registry of surgical procedures at two teaching hospitals in South Texas to calculate proportional operation ratios (PORs) for MAs versus WNHs. These two hospitals are the primary source of acute hospital care for the indigent in the area. The POR is arithmetically identical to proportional incidence and mortality ratios.

Results. MAs underwent appendectomy proportionally more often than WNHs at both hospitals (POR = 1.41 and 1.75, p < 0.0001). Other significant PORs were consistent with known ethnic disease differences in biliary tract operations, vascular access for chronic hemodialysis, lung cancer, and coronary artery bypass.

Conclusions. These findings support the hypothesis that MAs may undergo appendectomy more often than WNHs and so may be at higher risk of appendicitis.     

Diffusion of information about genetic risk within families

Recent developments in genetics are likely to exacerbate the ethical issues in clinical practice, especially with regard to privacy and disclosure of genetic information. To evaluate the behaviour of patients with respect to transmitting carrier information, we undertook a survey of 283 families with a balanced chromosomal rearrangement as a model. In these families, 1816 relatives were considered at risk and 806 of them were karyotyped (44.4%). The percentage of karyotypes performed is significantly related to the number of living children of the index couple, the reason for referral, the nature of the anomaly, the training of the counsellor and the age of the index case. This study shows the limits of the screening of at risk individuals within families, based on the willingness of the patients, and addresses practical and ethical issues around family disclosure in medical genetics.     

Programming a predictive rormula for angina and other risk factors in patients with cardiac diseases undergoing noncardiac operations

We programmed a formula which predicts the incidence of either myocardial infarction or cardiac death during the postoperative period. The original formula was proposed by Shah et al, based on their own data and analysis. The program is simple and is written in a language called Quick Basic. The use of this program is also simple. Such a program has improved the use of this analysis substantially. The program has been posted on to a few Computer network services as a free software.(Suwa K, Ogura S: Programming a predictive formula for angina and other risk factors in patients with cardiac diseases undergoing non-cardiac operations. J Anesth 6: 241–242, 1992)     

体力活动与乳腺癌发生的关系

目的:评估体力活动是否可降低中国妇女乳腺癌发生。材料与方法:本文利用1998年至2001年在上海市区开展的一项以人群为基础的乳腺癌病例对照研究数据,分析妇女既往不同年龄段(13～19岁青春期和近10年成年期)各种体力活动与乳腺癌的关系。在上海市共招收1 495名合格的乳腺癌病例和1 573名年龄频数匹配的全人群随机对照,应答率分别为95.1％和87.7％,在研究对象家中进行结构式问卷调查。结果:对可能的混杂因素校正后,发现青春期和成年期体育锻炼活动均能降低乳腺癌发生,每周运动量在75％分位数以上的妇女OR值分别为0.83(0.66～1.03)和0.64(0.46～0.87),趋势性检验的P值分别为0.040和0.002。两个年龄段做家务、骑自行车和成年期步行均与乳腺癌无关,但青春期较多步行可减少乳腺癌发生。另外未发现职业体力活动与乳腺癌有明显联系。最后对体育锻炼和日常生活体力活动的综合分析发现,只有成年期的体力活动具有独立的保护作用。结论:较多体力活动可降低中国妇女乳腺癌的发生,但仅成年期体力活动具有独立作用。