Behind the headlines: aircraft noise, statins, prostate biopsy
Published in Health News and Evidence
Date published: About this date
New to Health News and Evidence
Behind the Headlines looks at a selection of health stories reported in the media and goes behind the headlines to review the evidence.
In this inaugural Behind the Headlines we examine media reports that the role of statins in reducing CVD risk is overstated, whether aircraft noise increases risk of cardiovascular disease and if transperineal biopsy reduces harms of prostate biopsy
CVD risk and noise pollution?
Sydney Morning Herald, 11 October 2013
People in flight-path suburbs will agree that living close to an international airport can cause considerable distress and annoyance. But, does it also increase the risk of heart disease? The Sydney Morning Herald reported researchers have discovered a link.1 The report refers to research showing that people living near London Heathrow Airport were 24% more likely to be admitted to hospital with a stroke than people living in quieter areas of London. Is the evidence clear?
Aircraft noise and CVD – a developing body of evidence
There is a growing body of evidence suggesting chronic exposure to aircraft noise may increase CVD risk. The Sydney Morning Herald article reported on a study published in the British Medical Journal2 of the incidence of CVD in people living near Heathrow airport. On the same day the BMJ also published a similar study reporting CVD incidence around multiple airport sites in the United States.3
In the US study Medicare claims records were accessed from a population of over 6 million people living close to 89 airports.3 People living in postcodes that had a noise exposure level in the 90th centile had around a 3.5% higher admission rate for cardiovascular causes, although the statistical significance of this finding was not reported. This effect occurred even after controlling for possible socioeconomic and environmental confounders such as ethnicity and pollution levels.
The UK study reported hospital admission rates and mortality from stroke, coronary artery disease and cardiovascular disease in 3.6 million people living near Heathrow airport.2 After controlling for socioeconomic factors and relative air pollution there was a significant linear relationship between risk of hospitalisation due to cardiovascular causes and increasing levels of aircraft noise (P<0.001). There was a similar pattern with cardiovascular mortality. The relative risk for stroke was 1.24 (95% CI 1.08 to 1.43), coronary artery disease was 1.21 (95% CI 1.12 to 1.31) and cardiovascular disease was 1.14 (95% CI 1.08 to 1.20) for people living in areas with a daytime aircraft noise level of > 63 dB vs ≤ 51 dB.
There are obvious potential confounders in both studies. In studies of the impact of environmental factors on disease development and progression it is notoriously difficult to control for confounders such as smoking and diabetes. The UK study acknowledged this as a key limitation, especially considering they did not have access to individual patient data so could not assess each hospitalised study patient for individual risk factors.2
How does this evidence translate into practice?
While the question of what to do about aircraft noise is more a matter for city planners, should health professionals consider exposure to noise pollution when performing CVD risk assessments? The reported 24% increase in hospitalisation for strokes refers to relative risk increase, compared to areas in the UK with lowest noise pollution. The research did not report on absolute risk increase so it is currently not known what the absolute risk increase is for people living in areas with high levels of aircraft noise.
Information for patients
- People living around airports may be understandably concerned that their exposure to aircraft noise may increase their risk of CVD, but the impact on absolute risk is not currently known.
- Advise patients that addressing lifestyle factors (stopping smoking, healthy diet and physical activity, healthy weight and moderating alcohol intake) all provide proven protection against cardiovascular disease.
Catalyst (ABC TV), 31 October 2013
The Heart of the Matter6, a two part program from the ABC’s Catalyst series, challenged the widely held view that dietary saturated fats contribute to heart disease by raising blood cholesterol levels. This sparked public debate about whether the current guidelines for management of cardiovascular disease places undue emphasis on cholesterol and whether the prescribing practices for statins are warranted. The concern from the medical community was that people taking statins who watched this show may believe they no longer need to take their medicines. In this article we look at three key points raised in the Catalyst program and offer an evidence-based analysis of the claims.
Do statins benefit most people?
Views were expressed that, for most people statins provide no real benefit in terms of prolonging life.6
The evidence is clear on this: for people who have an elevated absolute risk of CVD, or have already had an event, statins reduce the risk of cardiovascular events and death.7-10
The RACGP recommends measuring circulating lipids in all people over the age of 45 as part of an absolute CVD risk assessment, and to provide lifestyle advice and consider blood pressure lowering medication and statins for those patients who are deemed to be at a moderate to high risk of a cardiovascular event.4
Do statins benefit men and women equally?
It was stated on the program that the evidence for statin efficacy in women was lacking.
While the effect of statins on the prevention of cardiovascular risk is well known it is less well established whether this effect is equal between men and women. However, two recent meta-analyses present data that suggest there is an overall positive benefit for statin therapy in women who are at increased risk of CVD or who have already had a cardiovascular event.11,12
Statins effectively reduce cardiovascular risk in women
A meta-analysis of 11 trials investigating gender differences in statin efficacy and safety for preventing recurrent cardiovascular events found statin therapy was associated with a similar cardiovascular event risk reduction in women and men.11 A reduction in risk for all cause mortality and stroke was demonstrated only in men. However, women were only 20% of the trial populations and so these studies may have been underpowered to detect gender differences. The authors concluded that statins are as effective in the prevention of recurrent cardiovascular events in women as men.11
A second meta-analysis, that included 18 trials of statins, found no difference in efficacy of statins in men vs women.12
What about side-effects?
Views were expressed in the program about significant side effects associated with the use of statins.
Post-market analysis has shown that statins are commonly associated with muscular complaints,13 but these appear to depend on statin dose and potency. If a patient is experiencing muscular aches consider reassessment of their statin therapy. Pravastatin and lovastatin appear to have the lowest risk of muscular symptoms whereas rosuvastastin may have the highest.13
Other side effects of statins have been reported, such as memory loss and increased risk of type 2 diabetes and cancer.6 A recent review found no evidence of association with memory loss and cancer, but a slight increase in risk for incidence of type 2 diabetes.14 The risk of diabetes was small, and when compared to a reduction in cardiovascular events of around 30% it was concluded that statins still represent an effective and safe means of cardiovascular risk management.14
Information for patients
- Reassure patients with moderate to high absolute risk of CVD that statins remain an effective part of a CVD risk reduction strategy regardless of gender.11,12
Simply stating facts and statistics may not be enough to convince some patients. Consider completing an absolute CVD risk calculation with the patient to help frame their risk.
The Age, 25 September 2013
In September, The Age newspaper reported that some Australian men may be exposed to an increased risk of serious infections from prostate biopsies where transrectal biopsy is used rather than transperineal prostate biopsy.16 The article reported two deaths in Victoria in the past five years resulting from post-biopsy infection as well as significant septicaemia-related morbidity.
Risk of sepsis with transrectal biopsy
Transrectal biopsy is the standard method of sampling cells from the prostate but may be associated with adverse outcomes.17 A recent systematic review found that infectious complications occur in up to 6.3% of men following transrectal biopsies, and there is also an increase in the incidence of infectious complications and antimicrobial resistance.17
Transperineal biopsy an option
Transperineal prostate biopsy reduces the risk of infection by accessing the prostate through the perineal wall instead of the rectum. A recent study of 3000 men undergoing transperineal biopsy reported a complication rate of 40.2%, but only 1.2% of these required hospitalisation, and a urinary tract infection rate of 0.7% with no reported sepsis.18 This may be an option for men at high risk of developing sepsis, such as those with diabetes or those who have recently travelled to countries with a high prevalence of antimicrobial resistance.19 This technique is also associated with increased cancer detection rates because of better sampling from the anteroapical and peripheral portions of the prostate.19
The implications for primary care practitioners
Regardless of the method used for prostate biopsy, one important implication of this report is a reminder that there are significant harms associated with undergoing prostate biopsy.20-22 Routine testing for prostate cancer using prostate specific antigen (PSA) and/or digital rectal examination (DRE) is not recommended in Australia as the harms are considered to outweigh the benefits.4
For more information on the harms and benefits of prostate cancer tests see
Information for patients
- Inform patients before undertaking a PSA test that they may need a biopsy to follow-up if their test result is suspicious.
- Inform patients of the potential side effects of prostate biopsy including the risk of infection.
For more information about the recommendations for see our page on prostate cancer screening
- Sydney Morning Herald. Research links aircraft noise to higher rates of heart disease. 2013. [Online] (accessed 11 October 2013).
- Hansell AL, Blangiardo M, Fortunato L, et al. Aircraft noise and cardiovascular disease near Heathrow airport in London: small area study. BMJ 2013;347:f5432. [PubMed]
- Correia AW, Peters JL, Levy JI, et al. Residential exposure to aircraft noise and hospital admissions for cardiovascular diseases: multi-airport retrospective study. BMJ 2013;347:f5561. [PubMed]
- Guidelines for preventive activities in general practice (The Red Book) 8th Edition. Melbourne: The Royal Australian College of General Practitioners, 2012. [Online] (accessed 11 February 2013).
- National Vascular Disease Prevention Alliance. Guidelines for the management of absolute cardiovascular disease risk. 2012. [Online] (accessed 30 October 2013).
- Catalyst. Heart of the matter 2013. [Online] (accessed 1 November 2013).
- Baigent C, Keech A, Kearney PM, et al. Efficacy and safety of cholesterol-lowering treatment: prospective meta-analysis of data from 90,056 participants in 14 randomised trials of statins. Lancet 2005;366:1267–78. [PubMed]
- Heart Protection Study Collaborative Group. MRC/BHF Heart Protection Study of cholesterol lowering with simvastatin in 20,536 high-risk individuals: a randomised placebo-controlled trial. Lancet 2002;360:7–22. [PubMed]
- Mihaylova B, Emberson J, Blackwell L, et al. The effects of lowering LDL cholesterol with statin therapy in people at low risk of vascular disease: meta-analysis of individual data from 27 randomised trials. Lancet 2012;380:581–90. [PubMed]
- Taylor F, Huffman MD, Macedo AF, et al. Statins for the primary prevention of cardiovascular disease. Cochrane Database Syst Rev 2013;1:CD004816. [PubMed]
- Gutierrez J, Ramirez G, Rundek T, et al. Statin therapy in the prevention of recurrent cardiovascular events: a sex-based meta-analysis. Arch Intern Med 2012;172:909–19. [PubMed]
- Kostis WJ, Cheng JQ, Dobrzynski JM, et al. Meta-analysis of statin effects in women versus men. J Am Coll Cardiol 2012;59:572–82. [PubMed]
- Hoffman KB, Kraus C, Dimbil M, et al. A survey of the FDA's AERS database regarding muscle and tendon adverse events linked to the statin drug class. PLoS One 2012;7:e42866. [PubMed]
- Jukema JW, Cannon CP, de Craen AJ, et al. The controversies of statin therapy: weighing the evidence. J Am Coll Cardiol 2012;60:875–81. [PubMed]
- Australian Institute of Health and Welfare. Australia's Health 2012. 2012. [Online] (accessed 11 February 2013).
- The Age. Prostate biopsy blamed for preventable superbug deaths. 2013. [Online] (accessed 25 September 2013).
- Loeb S, Vellekoop A, Ahmed HU, et al. Systematic review of complications of prostate biopsy. Eur Urol 2013;64:876–92. [PubMed]
- Pepe P, Aragona F. Morbidity after transperineal prostate biopsy in 3000 patients undergoing 12 vs 18 vs more than 24 needle cores. Urology 2013;81:1142–6. [PubMed]
- Chang DT, Challacombe B, Lawrentschuk N. Transperineal biopsy of the prostate-is this the future? Nat Rev Urol 2013. doi: 10.1038/nrurol.2013.195. [Epub ahead of print] [PubMed]
- Loeb S, Carter HB, Berndt SI, et al. Complications after prostate biopsy: data from SEER-Medicare. J Urol 2011;186:1830–4. [PubMed]
- Nam RK, Saskin R, Lee Y, et al. Increasing hospital admission rates for urological complications after transrectal ultrasound guided prostate biopsy. J Urol 2013;189:S12–7; discussion S7–8. [PubMed]
- Rosario DJ, Lane JA, Metcalfe C, et al. Short term outcomes of prostate biopsy in men tested for cancer by prostate specific antigen: prospective evaluation within ProtecT study. BMJ 2012;344:d7894. [PubMed]