Effects of cholesterol-lowering with simvastatin on stroke and other major vascular events in 20536 people with cerebrovascular disease or other high-risk conditions.

BACKGROUND: Lower blood cholesterol concentrations have consistently been found to be strongly associated with lower risks of coronary disease but not with lower risks of stroke. Despite this observation, previous randomised trials had indicated that cholesterol-lowering statin therapy reduces the risk of stroke, but large-scale prospective confirmation has been needed. METHODS: 3280 adults with cerebrovascular disease, and an additional 17256 with other occlusive arterial disease or diabetes, were randomly allocated 40 mg simvastatin daily or matching placebo. Subgroup analyses were prespecified of first "major vascular event" (ie, non-fatal myocardial infarction or coronary death, stroke of any type, or any revascularisation procedure) in prior disease subcategories. Subsidiary outcomes included any stroke, and stroke sub-type. Comparisons are of all simvastatin-allocated versus all placebo-allocated participants (ie, "intention-to-treat"), which yielded an average difference in LDL cholesterol of 1.0 mmol/L (39 mg/dL) during the 5-year treatment period. FINDINGS: Overall, there was a highly significant 25% (95% CI 15-34) proportional reduction in the first event rate for stroke (444 [4.3%] simvastatin vs 585 [5.7%] placebo; p<0.0001), reflecting a definite 28% (19-37) reduction in presumed ischaemic strokes (p<0.0001) and no apparent difference in strokes attributed to haemorrhage (51 [0.5%] vs 53 [0.5%]; rate ratio 0.95 [0.65-1.40]; p=0.8). In addition, simvastatin reduced the numbers having transient cerebral ischaemic attacks alone (2.0% vs 2.4%; p=0.02) or requiring carotid endarterectomy or angioplasty (0.4% vs 0.8%; p=0.0003). The reduction in stroke was not significant during the first year, but was already significant (p=0.0004) by the end of the second year. Among patients with pre-existing cerebrovascular disease there was no apparent reduction in the stroke rate, but there was a highly significant 20% (8-29) reduction in the rate of any major vascular event (406 [24.7%] vs 488 [29.8%]; p=0.001). The proportional reductions in stroke were about one-quarter in each of the other subcategories of participant studied, including: those with coronary disease or diabetes; those aged under or over 70 years at entry; and those presenting with different levels of blood pressure or lipids (even when the pretreatment LDL cholesterol was below 3.0 mmol/L [116 mg/dL]). INTERPRETATION: Much larger numbers of people in the present study suffered a stroke than in any previous cholesterol-lowering trial. The results demonstrate that statin therapy rapidly reduces the incidence not only of coronary events but also of ischaemic strokes, with no apparent effect on cerebral haemorrhage, even among individuals who do not have high cholesterol concentrations. Allocation to 40 mg simvastatin daily reduced the rate of ischaemic strokes by about one-quarter and so, after making allowance for non-compliance in the trial, actual use of this regimen would probably reduce the stroke rate by about a third. HPS also provides definitive evidence that statin therapy is beneficial for people with pre-existing cerebrovascular disease, even if they do not already have manifest coronary disease

Statistical Analysis of the Bio-assay of Continuous Carcinogens

In an experiment consisting of the continuous constant application of various carcinogenic regimens to a pure strain of experimental animals for a long period, the cancer incidence rates so caused may be studied and compared by the fit of an appropriate class of statistical distributions. In this paper we show that a Weibull distribution in which the age-specific cancer incidence rate rises as a power of time since first risk is more appropriate than a lognormal distribution. If the Weibull family of distributions is used, more information can be extracted from the data, and differences of toxicity between various regimens will not bias the comparison of their carcinogenic forces

Verbal autopsy of 48 000 adult deaths attributable to medical causes in Chennai (formerly Madras), India

BACKGROUND: In the city of Chennai, India, registration of the fact of death is almost complete but the cause of death is often inadequately recorded on the death certificate. A special verbal autopsy (VA) study of 48 000 adult deaths in Chennai during 1995–97 was conducted to arrive at the probable underlying cause of death and to measure cause specific mortality rates for Chennai. METHODS: Trained non-medical graduates with at least 15 years of formal education interviewed the surviving family members or an associate of the deceased to write a report on the complaints, symptoms, signs, duration and treatment details of illness prior to death. Each report was reviewed centrally by two physicians independently. The reliability was assessed by comparing deaths attributed to cancer by VA with records in Vital Statistics Department and Chennai Cancer Registry. RESULTS: The VA reduced the proportion of deaths attributed to unspecified medical causes and unknown causes from 37% to 7% in early adult life and middle age (25–69 yrs) and has yielded fewer unspecified causes (only 10%) than the death certificate. The sensitivity of VA to identify cancer was 94% in the age group 25–69. CONCLUSION: VA is practicable for deaths in early adult life or middle age and is of more limited value in old age. A systematic program of VA of a representative sample of deaths could assign broad causes not only to deaths in childhood (as has previously been established) but also to deaths in early adult life and middle age

COVID-19 vaccine trials should seek worthwhile efficacy.

No Abstrac

Effects of deworming on malnourished preschool children in India: an open-labelled, cluster-randomized trial.

BACKGROUND: More than a third of the world's children are infected with intestinal nematodes. Current control approaches emphasise treatment of school age children, and there is a lack of information on the effects of deworming preschool children. METHODOLOGY: We studied the effects on the heights and weights of 3,935 children, initially 1 to 5 years of age, of five rounds of anthelmintic treatment (400 mg albendazole) administered every 6 months over 2 years. The children lived in 50 areas, each defined by precise government boundaries as urban slums, in Lucknow, North India. All children were offered vitamin A every 6 months, and children in 25 randomly assigned slum areas also received 6-monthly albendazole. Treatments were delivered by the State Integrated Child Development Scheme (ICDS), and height and weight were monitored at baseline and every 6 months for 24 months (trial registration number NCT00396500). p Value calculations are based only on the 50 area-specific mean values, as randomization was by area. FINDINGS: The ICDS infrastructure proved able to deliver the interventions. 95% (3,712/3,912) of those alive at the end of the study had received all five interventions and had been measured during all four follow-up surveys, and 99% (3,855/3,912) were measured at the last of these surveys. At this final follow up, the albendazole-treated arm exhibited a similar height gain but a 35 (SE 5) % greater weight gain, equivalent to an extra 1 (SE 0.15) kg over 2 years (99% CI 0.6-1.4 kg, p = 10(-11)). CONCLUSIONS: In such urban slums in the 1990s, five 6-monthly rounds of single dose anthelmintic treatment of malnourished, poor children initially aged 1-5 years results in substantial weight gain. The ICDS system could provide a sustainable, inexpensive approach to the delivery of anthelmintics or micronutrient supplements to such populations. As, however, we do not know the control parasite burden, these results are difficult to generalize. TRIAL REGISTRATION: ClinicalTrials.gov NCT00396500