 No Breast Cancer-Abortion Link
Beer heightens risk of gout, but not wine
ABORTION DOES NOT INCREASE BREAST-CANCER RISK
The totality of the worldwide evidence does not suggest any increase in the risk of developing breast cancer for women who have had a pregnancy that ended in miscarriage or induced abortion, authors of a major international study conclude.
The Collaborative Group on Hormonal Factors in Breast Cancer (secretariat based at the University of Oxford, UK) reanalyzed data from 53 epidemiological studies undertaken in 16 countries.
Data were available from 44,000 women who had taken part in studies where any history of abortion had been recorded before-and often many years before-any breast cancer was diagnosed. Results were expressed as the "relative risk" of breast cancer, which compares the chances of developing breast cancer in women with and without such record of abortion.
A relative risk of 1.0 or lower 0 would indicate no adverse effect on the subsequent risk of breast cancer. In these studies, the averaged relative risk of breast cancer was 0.98 for women who had had a pregnancy that ended as a miscarriage and 0.93 for women who had had a pregnancy that ended as an induced abortion, indicating no increased risk of breast cancer after miscarriage or abortion. The number of abortions was also not associated with any change in breast-cancer risk.
"The totality of the worldwide epidemiological evidence indicates that pregnancies ended by induced abortion do not have adverse effects on women's subsequent risk of developing breast cancer," commented Prof. Valerie Beral.
Data on 39,000 women with breast cancer in potentially less reliable studies (where women were asked after the diagnosis of breast cancer about any previous abortions) gave misleading results on average.
"Studies can give misleading results if women are asked about previous abortions only after they are diagnosed with breast cancer," said Prof. Richard Peto. "This may well be because, on average, women with breast cancer are more likely than other women to disclose any prior induced abortions." (363: 1007-16)
WHY THE LOW HIV RISK AMONG CIRCUMCISED MEN
Research from India suggests that circumcised men could be over six times less likely than uncircumcised men to acquire HIV infection. The study also shows how the explanation for this decreased risk in circumcised men is likely to be biological rather than behavioral, with thin tissue in the foreskin being the likely target for viral activity.
Previous research has shown that circumcised men have a lower risk of HIV-1 infection than uncircumcised men. Laboratory findings have suggested that the foreskin is enriched with HIV-1 target cells. However, other studies have suggested that circumcision could be an indicator for low-risk sexual behavior.
Dr. Robert C. Bollinger and colleagues from Johns Hopkins University Medical School and the National AIDS Research Institute in India, observed how uncircumcised men attending sexually transmitted infection clinics in India were over six times more likely to acquire HIV infection than men who had been circumcised. All men were HIV-negative when first assessed; most men were assessed three times after initial assessment for around a year. No protective effect of circumcision against herpes simplex virus type 2, syphilis or gonorrhea was found.
"These data confirm previous findings that male circumcision reduces the risk of HIV-1 acquisition," said Bollinger.
He said the analysis expands on earlier studies by including laboratory-defined incident STIs as outcomes in the analysis, as well as by including risk behavior to control for other potential differences between circumcised and uncircumcised men.
"A unique and important finding was a highly significant and specific protective effect of male circumcision on the risk of HIV-1 acquisition," he noted. However, the data failed to show a significant protective effect of circumcision on the risk of the other STIs.
"These epidemiological data lend support to the hypothesis that male circumcision protects against HIV -1 infection primarily due to removal of the foreskin, which contains a high density of HIV -1-specific cellular targets, including CD4+ T-lymphocytes and Langerhans' cells, which are easily accessible to the virus through the thin layer of keratin overlying the inner mucosa," he added. (363: 1039-40)
NEW DRUG-RESISTANT STRAIN OF SALMONELLA IDENTIFIED
Researchers from Taiwan have reported the identification of a new form of drug-resistant salmonella.
Salmonella enterica serotype choleraesuis usually causes infections that require antimicrobial treatment. Multidrug-resistant strains have been identified, but the antimicrobial ceftriaxone has been effective against them so far.
Prof. J. T. Ou, from Chang Gung University College of Medicine and colleagues isolated a strain of Salmonella enterica serotype choleraesuis that was resistant to all antimicrobials commonly used to treat salmonellosis, including ceftriaxone and ciprofloxacin. The bacteria came from a 58-year-old man with sepsis who subsequently died.
The drug resistance was due to changes in the genes of the bacteria, including some in a genetic element that can potentially be transmitted between bacteria. Although this strain was from only one patient, the public-health implications of multidrug-resistant salmonella are serious.
"Constant surveillance is needed to prevent its further spread," warned the authors. (363: 1285-86)
ALCOHOL CONSUMPTION INCREASES RISK OF GOUT
Beer drinking was more likely to be associated with gout than spirits, while moderate wine consumption was not linked to a risk of the disease, the first large epidemiological study to assess the age-old belief that alcohol consumption increases the risk of gout concludes.
Alcohol consumption causes increased production of uric acid that when deposited in joints leads to gout. The association between alcohol consumption and risk of gout has been suspected since ancient times, but has not been prospectively confirmed. Additionally, potential differences in risk of gout posed by different alcoholic beverages have not been assessed.
Dr. Hyon K. Choi of Massachusetts General Hospital and his colleagues prospectively assessed alcohol consumption and incidence of gout among 47,000 male medical staff over 12 years. They confirmed 730 cases of gout throughout the study period. Alcohol consumption was assessed as the quantity consumed relative to the typical ethanol content of alcoholic drinks: 12.8g for one can of beer, 11g for a glass of wine, and 14g for a shot of spirits.
Alcohol consumption was linked to gout risk, with higher overall consumption increasing this risk: around 30-percent increased risk for daily alcohol consumption between 10 and 15g; around 50-percent increased risk for daily consumption between 15 and 30g; around a doubling of gout risk for consumption between 30 and 50g; and 2.5 times increased risk for a daily alcohol consumption above 50g.
Beer consumption showed the strongest independent association with the risk of gout. Consumption of spirits had a weaker association, while moderate wine consumption was not associated with increased gout risk.
"We found differences in the risk of gout for the three alcoholic beverages. Two or more beers per day increased the risk of gout 2.5 times compared with no beer intake, whereas the same frequency of spirits intake increased the risk by 1.6 times compared with no spirits intake," commented Choi.
"Correspondingly, beer increased the risk of gout per serving per day more than twice as much as did spirits even though alcohol content per serving was less for beer than spirits. Further, wine consumption of two four-ounce glasses or more per day was not associated with an increased risk of gout," he explained.
Choi said the findings suggest that certain nonalcoholic components that vary across these alcoholic beverages play an important role in the incidence of gout. One candidate for this nonalcoholic component is the variation in purine contents among the individual alcoholic beverages.
Said Choi: "Beer is the only alcoholic beverage acknowledged to have a large purine content.Thus, the effect of ingested purine in beer on uric acid in blood might be sufficient to augment the hyperuricaemic effect of alcohol itself producing a greater risk of gout than spirits or wine. Whether there might be other nonalcoholic risk factors in beer, or protective factors in wine, remains unknown." (363: 1251, 1277-81)
SACRAL-NERVE STIMULATION COUNTERACTS INCONTINENCE
Results of a small trial suggest that electrical stimulation of the sacral nerve could be a future treatment option for fecal incontinence.
Dr. Klaus Matzel of the University of Nuremberg in Germany and colleagues investigated the effect of sacral nerve stimulation on continence and quality of life.
Thirty-four patients from eight medical centers had electrodes implanted to stimulate the sacral nerve and facilitate greater control of the anal sphincter. Patients were asked to keep a record of incontinence episodes and were followed up at various intervals for three years after.
Stimulation of the sacral nerve greatly reduced the number of weekly episodes of incontinence, from around 16 per week at the start of the study to around three (after one year of treatment) and two (after two years of follow-up).
The authors also noted a reduction in the average number of incontinent days per week and in use of incontinence pads. Patients also reported improvement in their quality of life.
Matzel said the trial showed convincing benefit of sacral nerve stimulation to continence and quality of life for patients with fecal incontinence. "The technique is relatively simple, and its practicality is enhanced by the predictive value of a staged approach, in which every patient serves as his or her own control," he said.
"With its low morbidity, sacral nerve stimulation is a safe and effective option for patients with an intact or repaired anal sphincter. When conventional treatment is inappropriate or ineffective, it should be considered before sphincter replacement or stoma creation".
Anal incontinence affects an estimated two percent of the general population. Prevalence rises with age, affecting up to 11 percent of men and 26 percent of women after age 50 years. Treatment options are limited for patients with fecal incontinence in whom conservative treatment like diet changes and pelvic-floor exercise to increase muscle tone fails. (363: 1270-76)
|
