Irritable bowel syndrome (IBS) is a condition characterised by symptoms such as abdominal discomfort, bloating, wind and altered bowel habit. In conventional medicine, there is no real consensus on what causes IBS. IBS is what might be termed a “diagnosis of exclusion”. In other words, it’s the diagnosis that individuals end up with when tests have revealed there’s no conventional explanation for the symptoms (such as inflammatory bowel disease).

My experience in practice has led me to believe that IBS usually does have one or more specific underlying cause – it’s just that these tend not to be tested for and/or recognised by conventional medicine. I find the top two causes of this condition are food sensitivity and an imbalance in the organisms that inhabit the gut. For more about this, see a previous blog post here.

Despite conventional medicine’s generally poor understanding of IBS, certain strategies do exist for its treatment. For example, some health professionals will advise that individuals with IBS increase their intake of fibre. In practice, I’ve found that this makes many patients worse. One potential explanation for this concerns wheat which is, in my experience, a common triggering factor in IBS. And when individuals are advised to consume more fibre, they almost inevitably opt for more in the way of high-fibre breakfast cereals and breads that are based on wheat.

Fibre as a treatment for IBS has been studied, and a review of the available evidence has been published in the British Medical Journal this week [1]. There are two main sorts of fibre that have been studied in this context: bran (usually from wheat) and ispaghula (derived from plaintain). Bran was not found to bring a statistically significant reduction in the risk of persistent IBS symptoms, though ispaghula (also known as psyllium) did. Ispaghula was found to reduce the risk of persistent symptoms by 22 per cent.

This review also looked at other strategies for IBS, including drugs that reduce spasm in the gut wall known as “anti-spasmodics”. 12 agents were assessed, of which only 5 brought statistically significant improvements in symptoms. Curiously, some drugs licensed for use for IBS (e.g. mebeverine) did not seem to have any good evidence for them. Only two agents (otilonoium and hyoscine) showed, according to the authors, “consistent evidence of benefit”. Of these two, the one with the best evidence appears to be hyoscine (Buscopan).

One final treatment assessed by the review was peppermint oil. This folksy remedy turned out to be better than placebo, reducing risk of persistent symptoms by more than half (57 per cent).

Another way the effectiveness of a treatment can be assessed is to measure the “number needed to treat” (the number of individuals that need to be treated for one to get benefit”. This review found the following NNTs for the treatments they assessed:

NNT for fibre: 11

NNT for peppermint oil: 2.5

Of these three main approaches for IBS, peppermint oil looks like the stand-out winner. My preference is still to attempt to elucidate the true underlying cause of someone’s IBS symptoms rather than merely treating the symptoms (see link above). That said, peppermint oil represents a generally safe and effective option for those looking for some symptomatic relief from IBS.

References:

1. Ford AC, et al. Effect of fibre, antispasmodics, and peppermint in the treatment of irritable bowel syndrome. BMJ 2008;337;a2313

For a long time now I’ve been a fan of sleep. Not just because of its relatively immediate impact on energy levels and sense of wellbeing, but also because of the research which links adequate sleep with improved health in the long term. Short sleep times have, for instance, been linked with an increased risk of heart disease. One such study as published this week in the Archives of Internal Medicine. The population being studied comprised more than 1200 Japanese men and women with an average age of 70. The group was followed for an average of just over 4 years.

All the members of this group were suffers of hypertension (high blood pressure). The individuals were assessed to see how their blood pressure at night compared with levels during the day. Generally, blood pressure falls at night. However, in some of the group blood pressure rose slightly (referred to in the study as a ‘riser pattern’).

Overall, individuals sleeping for less than 7.5 hours a night, compared to those sleeping longer, were found to be at a 68 per cent increased risk of cardiovascular disease (heart attack and stroke), death from cardiovascular disease, or what is known as sudden cardiac death. The greatest risk appeared to be for those who in addition to sleeping less than 7.5 hours, also exhibited the ‘riser pattern’ in terms of their blood pressure. Compared to those without this pattern who also slept for long, this subgroup were about four and half times more likely to suffer from one of the endpoints monitored in the study.

It is not possible from epidemiological studies to know if lower sleep times increases risk of cardiovascular disease and death, or these things are just associated with each other. However, there is at least some reason to think there is a causal link. Lack of sleep has been noted to increase activity in part of the nervous system known as the sympathetic nervous system. In turn, this can increase blood pressure. Suboptimal sleep has also been shown to induce changes which predispose towards insulin resistance (a precursor of type 2 diabetes and a risk factor for cardiovascular disease). And finally, lack of sleep has also been shown to cause a rise in the level of the inflammatory marker C reactive protein that is also associated with an increased risk of cardiovascular disease.

What this mean is that is at least some evidence which explains how a lack of sleep might increase the risk of cardiovascular disease. And all-in-all, there is good reason to believe not scrimping of sleep may add years to our life as well as life to our years.

References:

Eguchi K, et al. Short Sleep Duration as an Independent Predictor of Cardiovascular Events in Japanese Patients With Hypertension. Arch Intern Med. 2008;168(20):2225-2231