Lack of effect of lowering LDL cholesterol on cancer: meta-analysis of individual data from 175,000 people in 27 randomised trials of statin therapy

Background: Statin therapy reduces the risk of occlusive vascular events, but uncertainty remains about potential effects on cancer. We sought to provide a detailed assessment of any effects on cancer of lowering LDL cholesterol (LDL-C) with a statin using individual patient records from 175,000 patients in 27 large-scale statin trials. Methods and Findings: Individual records of 134,537 participants in 22 randomised trials of statin versus control (median duration 4.8 years) and 39,612 participants in 5 trials of more intensive versus less intensive statin therapy (median duration 5.1 years) were obtained. Reducing LDL-C with a statin for about 5 years had no effect on newly diagnosed cancer or on death from such cancers in either the trials of statin versus control (cancer incidence: 3755 [1.4% per year [py]] versus 3738 [1.4% py], RR 1.00 [95% CI 0.96-1.05]; cancer mortality: 1365 [0.5% py] versus 1358 [0.5% py], RR 1.00 [95% CI 0.93-1.08]) or in the trials of more versus less statin (cancer incidence: 1466 [1.6% py] vs 1472 [1.6% py], RR 1.00 [95% CI 0.93-1.07]; cancer mortality: 447 [0.5% py] versus 481 [0.5% py], RR 0.93 [95% CI 0.82-1.06]). Moreover, there was no evidence of any effect of reducing LDL-C with statin therapy on cancer incidence or mortality at any of 23 individual categories of sites, with increasing years of treatment, for any individual statin, or in any given subgroup. In particular, among individuals with low baseline LDL-C (<2 mmol/L), there was no evidence that further LDL-C reduction (from about 1.7 to 1.3 mmol/L) increased cancer risk (381 [1.6% py] versus 408 [1.7% py]; RR 0.92 [99% CI 0.76-1.10]). Conclusions: In 27 randomised trials, a median of five years of statin therapy had no effect on the incidence of, or mortality from, any type of cancer (or the aggregate of all cancer).

Biogas production from novel substrates

Biogas production is the conversion of the organic material into methane (CH4) and carbon dioxide (CO2) under anaerobic conditions. Anaerobic digestion (AD) is widely used in continental and Scandinavian communities as both a waste treatment option and a source of renewable energy. Ireland however lags behind this European movement. Numerous feedstocks exist which could be digested and used to fuel a renewable transport fleet in Ireland. An issue exists with the variety of feedstocks; these need to be assessed and quantified to ascertain their potential resource and application to AD. From literature the ideal C:N ratio is between 25 and 30:1. Low levels of C:N (<15) can lead to problems with ammonia inhibition. Within the digester a plentiful supply of nutrients and a balanced C:N is required for stable performance. Feedstocks were sampled from a range of over 100 different substrates in Ireland including for first, second and third generation feedstocks. The C:N ranged from 81:1 (Winter Oats) to 7:1 (Silage Effluent). The BMP yields were recorded ranging from 38 ± 2.0 L CH4 kg−1 VS for pig slurry (weaning pigs) to 805 ± 57 L CH4 kg−1 VS for used cooking oil (UCO). However the selection of the best preforming feedstock in terms of C:N ratio or BMP yield alone is not sufficiently adequate. A total picture has to be created which includes C:N ratio, BMP yield, harvest yield and availability. Potential feedstocks which best meet these requirements include for Grass silage, Milk processing waste (MPW) and Saccharina latissima. MPW has a potential of meeting over 6 times the required energy for Ireland’s 2020 transport in energy targets. S. Latissima recorded a yield of over 10,000 GJ ha-1 yr-1 which out ranks traditional second generation biofuels by a factor of more than 4.