Significant rise in colorectal cancer in young adults
NEW research has found a significant increase in the incidence of colorectal cancer (CRC) among young adults in the US since 1975, while incidence rates in older patients have declined. The US retrospective study, published in JAMA Surgery, analysed data from diagnoses of 393 241 patients with histologically confirmed colon or rectal cancer between 1975 and 2010 to evaluate age-related disparities in CRC incidence. Colon cancer represented 71.6% of all diagnoses, while the remainder were rectosigmoid and rectal cancers. The overall age-adjusted incidence rate of CRC decreased by 0.92% per year during the study period. While there was a steady decline in CRC diagnoses in patients aged 50 years and over, the opposite trend was observed for young adults aged 20‒34 years. The authors said that for patients in this age group, incidence rates of localised, regional and distant colon and rectal cancers increased. Rectal cancer incidence rates also rose for adults aged 35‒49 years. Based on these trends, by 2030 colon and rectal cancers were expected to increase by 90% and 124.2%, respectively, for patients aged 20‒34 years, the authors wrote. They said that further study was needed “to determine the cause for these trends and identify potential preventive and early-detection strategies”. An accompanying commentary said more widespread application of colonoscopic screening to all adults was not the preferred strategy to reduce the risk of CRC because of the low absolute risk of colorectal cancer in younger age groups. They said this strategy could add significant cost and risk “without societal benefit”, highlighting the need to develop “better risk-prediction tools”.
Repeated violent injury among youth
MORE than a third of youth treated in the emergency department (ED) for violent injury experience another such injury within 2 years, a prospective cohort study published in JAMA Pediatrics has found. Researchers compared the medical records of 349 youths who received ED care for an assault injury with 250 age-matched controls over a 2-year period. The mortality rate among all participants, aged 14–24 years, was 0.8%. The researchers found almost 36.7% of youth in the assault-injured group experienced a repeated violent injury which required hospital care, compared with 22.4% in the control group. The majority of repeated violent injuries occurred within 6 months of the initial ED visit. The authors found that patients with active post-traumatic stress disorders (PTSD) and drug use disorders were more likely to have recurring violent injuries requiring ED care. Females constituted nearly half of those who returned to the ED with an assault injury, highlighting “the need to develop violence interventions relevant to both sexes”, the authors wrote. The authors said a preventive care management plan to reduce recurrent costly ED visits was needed for youth presenting with a violent injury. “Future violence interventions for youth sustaining assault-related injury may be most effective in the first 6 months after injury, which is the period with the highest risk for recidivism. These interventions may be most helpful if they address substance use and PTSD to decrease future morbidity and mortality”, the authors wrote.
Fluids key in preventing kidney stones
A CLINICAL guideline has recommended increased fluid intake to prevent recurrent kidney stones, and adding pharmacological monotherapy if this fails to reduce stone formation. The guideline, published in the Annals of Internal Medicine was based on a systematic review of studies on nephrolithiasis in adults. The authors found that increasing fluid intake to achieve a urine output of at least 2 L/day reduced kidney stone recurrence by half, with no reported side effects. Other dietary interventions, including low protein diets, showed mixed results. The authors said that pharmacological therapies, specifically thiazide, citrate and allopurinol, produced a statistically significant decrease in kidney stones, although no trials directly compared these therapies. Negative side effects were sparsely reported in the literature, but they were more common for pharmacological than non-pharmacological therapies, the authors wrote. They recommended that if increased fluid intake failed to reduce the formation of kidney stones, patients should receive pharmacological monotherapy. Evidence also showed that patients who decreased their intake of soft drink acidified by phosphoric acid had reduced kidney stone occurrence. This highlighted the need for clinicians to “encourage patients to avoid colas as opposed to fruit-flavored soft drinks, which are often acidified by citric acid”, the authors wrote. They said their recommendations should only be applied to calcium stones as no trials assessing the treatment of uric acid or cysteine stones were reviewed.
Cognitive function at risk from shift work
SHIFT work is associated with chronic impairment of cognitive function in workers, a prospective cohort study published in Occupational & Environmental Medicine has found. Over a 10-year period, researchers used memory and speed tests to assess the cognitive abilities of 3232 employed and retired workers with varying levels of shift work experience. Shift workers recorded lower scores on memory, processing speed and overall cognitive function compared with those who did not work shifts. The association between shift work and cognitive decline was strongest in participants who had 10 or more years of exposure to shift work. The authors found that cognitive function took at least 5 years to recover after participants had ceased all shift work. The effects of shift work on an individual’s circadian rhythms, physiological stress, metabolism and vitamin D levels were identified as possible causes of cognitive impairment. The authors said the findings had significant safety consequences “not only for the individuals concerned, but also for society as a whole given the increasing numbers of jobs in high hazard situations that are performed at night”. They said the evidence of cognitive impairment highlighted the importance of maintaining medical surveillance of shift workers, especially for those who have remained in shift work for 10 years or more. Measures to mitigate the impact of prolonged exposure to shift work were also recommended, including switching to daytime work.
Neoplasms misdiagnosed as “chronic Lyme disease”
INFECTIOUS diseases physicians in the US have warned of the risks associated with the misdiagnosis of neoplasms as “chronic Lyme disease”, a term that they said should be avoided in a letter published in JAMA Internal Medicine. The authors reported the cases of three patients who were initially diagnosed with chronic Lyme disease after presenting with non-specific symptoms including joint pain, fatigue and abdominal pain. Further medical evaluation found these diagnoses were inaccurate, which delayed treatment for the patients’ actual conditions, the authors wrote. Two patients were diagnosed with chronic Lyme disease despite the lack of a suggestive clinical history (such as living in a Lyme disease-endemic area) and negative results for Lyme serological tests. The first patient was eventually found to have a pituitary tumour and symptoms consistent with acromegaly, but it was only possible to partially remove the tumour and the patient was left with permanent facial changes and cardiomyopathy. The second patient was diagnosed with stage IV Hodgkin lymphoma, and died 2 years later of complications from advanced lymphoma. A third patient had a clinical history and serum immunoassay results consistent with Lyme disease, but his presenting malaise and fatigue responded only transiently to doxycycline. He was ultimately diagnosed with a stage I non-small cell lung adenocarcinoma, which was successfully resected. The authors said the third patient most likely did have true Borrelia burgdorferi infection, for which antibiotic therapy was appropriate, but subsequent symptoms were incorrectly attributed to persistent infection. The authors wrote that “chronic Lyme disease” was a misleading term and that “posttreatment Lyme disease syndrome is the proper term for patients with a verified previous B burgdorferi infection”. The authors said they were not suggesting that all patients who presented with non-specific symptoms should be aggressively evaluated for cancer. Instead, these cases demonstrated the “delays in diagnosis that come from assuming that patients have chronic Lyme disease”.
AF doubles risk of developing silent stroke
ATRIAL fibrillation (AF) more than doubles the chances of developing a silent cerebral infarction (SCI), according to a systematic review and meta-analysis published in the Annals of Internal Medicine. The main meta-analyses dealt with studies where SCIs were detected using either computed tomography or magnetic resonance imaging. The authors wrote that the meta-analysis suggested SCIs were very common in patients with AF, with a prevalence of 40% across nine studies that used MRI for detection, and 22% across six studies that used CT. They found that having AF led to a twofold increase in the risk of developing SCI and that this link was independent of AF subtypes (paroxysmal versus persistent). The authors wrote that although SCIs did not present with acute stroke symptoms, in previous studies they had been associated with more than three- and twofold increases in the risk for symptomatic stroke and dementia, respectively. Few of the studies indicated a relationship between SCIs and death. As a result, the higher prevalence of SCIs in patients with AF “may put this population at greater risk for cognitive impairment, future stroke, and disability”. The authors wrote that there were several limitations to their meta-analysis, including that the quality of the studies was variable, and that there was inadequate information on the anticoagulation status of the patients in most studies. They said future research should focus on the spatial distribution of lesions, as well as the effectiveness of anticoagulant and antiplatelet therapy in preventing SCIs.