MinervaBMJ 2006; 332 doi: http://dx.doi.org/10.1136/bmj.332.7551.1222 (Published 18 May 2006) Cite this as: BMJ 2006;332:1222
Not getting enough sleep is a risk factor for high blood pressure, according to an analysis of the first national health and nutrition examination survey in the US (Hypertension 2006;47: 833-9). Sleeping less than five hours a night was associated with a significantly increased risk of hypertension in people aged between 32 and 59, a relation only partially attenuated by adjustment for potential confounding factors such as obesity and diabetes.
Vasopressin (anti-diuretic hormone), administered intranasally, has different effects on social communication skills in men and women. Men perceived the faces of unfamiliar men as being less friendly, but women perceived the faces of unfamiliar women as more friendly. Vasopressin also seems to have a role in evoking autonomic responses when we encounter threatening faces, and in increasing anxiety (Proceedings of the National Academy of Sciences 8 May 2006; doi: 10.1073/pnas.0600406103).
A study of 14 aphasic patients enabled researchers to describe how the brain zones for language are reorganised after stroke. Three phases seem to be involved in patients who had an infarction of the left middle cerebral artery: an initial acute phase wherein the remaining language areas in the left hemisphere show reduced activation; a subacute phase of greatly increased activation of language networks in both hemispheres, particularly on the right; and a chronic phase where the activation of language regions is normalised (Brain 25 April 2006; doi: 10.1093/brain/awl090).
Despite a low prevalence of smoking, the incidence of lung cancer in Chinese women is quite high. Attempting to resolve this puzzle, researchers performed a case-control study among non-smoking women in Hong Kong. They wanted to find out if cumulative exposure to cooking fumes was associated with increased risk of lung cancer. It was, with the odds ratio of lung cancer being highest for deep frying and lowest with stir frying (Cancer Research 2006;66: 4961-7).
Being a fan of neuroscience, Minerva was shocked to learn that a central belief in the study of mammalian circadian rhythms has been shaken. Two transcription factors, CLOCK and BMAL1, are thought to be essential components of the circadian clock in mice. However, after researchers removed the CLOCK protein from the equation, the defects seen in mice consisted only of mild alterations in response to light (Neuron 2006;50: 465-77).
The ALLHAT (antihypertensive and lipid lowering treatment for prevention of heart attack) Collaborative Group has published a new set of research findings on the efficacy of diuretics in preventing heart failure. The group analysed data from more than 33 300 people aged 55 or over who had participated in the original trial. The researchers conclude that diuretics are superior to calcium channel blockers or angiotensin converting enzyme inhibitors in preventing heart failure, at least in the short term (Circulation 2006;113: 2201-10).
Given the choice between waiting to receive an electric shock and getting it over with as quickly as possible, some people choose to have a stronger shock rather than wait for a mild shock. Not surprising, say the scientists who used functional magnetic resonance imaging to study neural responses to cutaneous shock. The levels of dread correlated well with the increase in neural activity in the posterior elements of the pain matrix and were a result of anticipating the adverse event, rather than of simple fear or anxiety (Science 2006;312: 754-8).
A psychological assessment at age 7 years of 90 children, followed up in the UK neonatal extracorporeal membrane oxygenation (ECMO) trial of severe respiratory failure at birth, reports that 76% of them had reached a cognitive level within the normal range. Learning difficulties were similar in the ECMO and conventional treatment groups, but respiratory morbidity and risk of behavioural problems were higher among children treated conventionally (Pediatrics 2006; 117: 845-54).
If you're born in April, May, or June, take care. A paper in the British Journal of Psychiatry (2006;188: 416-22) found that people who killed themselves were more likely to be born in these months. Overall the risk of suicide for people born in late spring was 17% higher than for those born in late autumn. This seasonal variation has a stronger effect on women than men.
It's still not clear what pattern of sun exposure causes malignant melanoma: short, intense, intermittent, or cumulative? Ultraviolet B or ultraviolet A, or both? Fifty years of research confirms that sun exposure initiates and promotes growth of melanoma and causes immunosuppression, but genetics also plays a role. And despite suggestions that sunscreens may be harmful, sun protection does seem to be prudent (Dermatologic Surgery 2006;32: 481-92).
Exciting new tests don't necessarily lead to more diagnoses being made. The introduction of a highly sensitive and rapid ELISA (enzyme linked immunosorbent assay) d-dimer test for diagnosing pulmonary embolus in one hospital emergency room simply increased evaluations for pulmonary embolus, D-dimer testing, and pulmonary vascular imaging. The study found no change in the rate of diagnosis of pulmonary embolus (Academic Emergency Medicine 2006;13: 519-24).
Recreational alpine skiers have proved surprisingly useful in studying the relation between menstrual cycle phase and anterior cruciate ligament injury (American Journal of Sports Medicine 2006;34: 757-63). The likelihood of sustaining such injuries is not constant during the menstrual cycle: the risk is much greater during the pre-ovulatory phase than the post-ovulatory phase. Minerva wonders whether this should be kept in mind when booking skiing holidays.
A Parisian doctor presented a paper to the French Academy of Medicine in 1856 about the strange behaviour of workers employed in the production of Indian rubber. They showed symptoms of mental derangement which resembled alcohol intoxication, with changeable moods of hilarity and manic outbursts followed by drowsiness, apathy, and inertia (Medical History 2006;50: 167-88). The cause was an organic solvent called carbon disulphide and it was the start of “organic solvent syndrome,” yet to be formally recognised in the UK.
Guidance at bmj.com/advice